System and method for transmitting electrical power

Abstract

SOLUTION: To provide a system for transmitting electrical power from an electrical power source to a receiver.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] cross reference This patent application claims the benefit of U.S. Provisional Patent Application No. 62 / 817,159, filed March 12, 2019, U.S. Provisional Patent Application No. 62 / 934,309, filed November 12, 2019, U.S. Provisional Patent Application No. 62 / 944,645, filed December 6, 2019, and U.S. Provisional Patent Application No. 62 / 956,479, filed January 2, 2020, each of which is incorporated herein by reference in its entirety.

[0002] Technical Field The present invention relates to a power transmitter, receiver, and system and method for power transmission. [Background technology]

[0003] In inductive power transfer (IPT), power is typically transferred between coils of wire by a magnetic field. An oscillating magnetic field is created when an alternating current (AC) is generated by a transmitting coil. This magnetic field passes through a receiving coil and induces an AC in it. The induced AC can either directly drive a load or be rectified to a direct current (DC) that is applied to drive a load. To achieve high efficiency, the transmitting and receiving coils must be in very close proximity. For example, it is common to find that the transmitter and receiver coils are separated by only a few coil diameters (e.g., within centimeters) and the coil axes are closely aligned.

[0004] Some IPT systems utilize resonant inductive coupling, which can increase the efficiency of IPT through the use of resonators. Resonant inductive coupling can achieve higher efficiency over longer distances than non-resonant inductive coupling. In resonant inductive coupling, power is transferred by a magnetic field between two resonators, one in the transmitter and the other in the receiver. The two circuits are tuned to resonate at the same resonant frequency.

[0005] In some IPT systems, the magnetic field can also induce eddy currents in nearby metals, which can cause significant heat buildup and a fire hazard. Ferrite plates may be used to provide shielding and improve inductive coupling, but can add cost to such systems.

[0006] Capacitive power transfer (CPT) uses an electric field to transmit power between two electrodes, such as metal plates. Typically, four metal plates are used in a CPT system to form a capacitive coupler. Using two plates as power transmitters and the other two plates acting as power receivers, at least two coupling capacitors create a power flow loop. An AC voltage is applied to the transmitting plate by the transmitter. The oscillating electric field induces an AC potential on the receiver plate, which causes an AC current to flow in the load circuit. Resonance can also be used along with capacitive coupling to extend the power transfer range.

[0007] In CPT systems, eddy current losses may be reduced, so lower cost plates are used, reducing the cost of the system. However, a problem with many systems is that high voltages may be applied to the plates. These high voltages create strong electric fields, which result in significant electric fields being radiated into the surrounding area.

[0008] CPT and IPT systems have issues with capacitive or inductive compensation networks. Currently, both CPT and IPT systems require minimal isolation between the receiver and transmitter. This typically requires large capacitors and inductors on the primary and secondary sides of the compensation network. Such large elements are difficult to manufacture, and their parasitic resistance can dramatically reduce system efficiency. In addition, these compensation elements do not directly participate in the power transfer process.

[0009] There remains a desire for wireless power transmitters and receivers with fewer components and / or reduced cost. There remains a desire for wireless power transmitters and receivers with less reliance on compensation networks. There remains a desire for more efficient wireless power transmitters and receivers. There remains a desire for wireless power transmitters with greater versatility in alignment and spacing requirements.

[0010] When it comes to consumer products, the field of power transmission is becoming even more important. In the automotive sector, electrical wiring harnesses have become a critical and cost-effective subsystem of the vehicle. The market for automotive wiring harnesses is estimated to exceed US$ 77 billion in the coming decade. In an era focused on internal combustion engine vehicle gasoline mileage, automotive carbon emissions, and electric vehicle range, the cost, weight, and power transmission efficiency of the aforementioned harnesses have become major concerns in automotive design. This concern can be understood when you consider that materials and components account for around 57% of the vehicle production cost.

[0011] Battery technology products are steadily improving to provide higher energy density batteries, but at the same time consumer demand is increasing as more ancillary user electronic devices and electric drive systems are integrated into vehicles. This places further demands on batteries, vehicle weight, cost, and power transfer efficiency. In the 1990s, higher voltage battery systems were proposed by the automotive industry, in part to reduce wiring harness weight.

[0012] There has been a significant effort to reduce the use of expensive copper in wiring harnesses, with a move towards the use of less expensive aluminum. This trend is further driven by the prospect of reducing the weight of a typical automobile by approximately 40 lbs. This trend towards aluminum is problematic in itself, in part because aluminum has a resistance 1.58 times that of copper. Aluminum also suffers from connections that can loosen, a phenomenon known as creep. Additionally, aluminum oxidizes, requiring careful use of connections. Copper is still required in some aspects of wiring harnesses, and copper-to-aluminum connections can present galvanic potential problems.

[0013] There is a clear need for an alternative approach to vehicle wiring harnesses that reduces expensive copper content, provides voltage flexibility, avoids the problems caused by aluminum, and reduces weight.

[0014] At the same time, the efficiency of power transmission technologies needs to improve to keep up with the rapidly advancing battery technology that is accompanying developments in the electric vehicle sector.

[0015] These requirements are not limited to the automotive sector, but also belong for example to the sector of solar energy power transmission and, with some modifications, also apply to consumer household appliances such as computer and television displays. Power conditioning units that optimally extract power from sources with fluctuating voltages are widely used today, but these units generally have a limited degree of control equipment, which results in a non-optimized power transmission efficiency.

[0016] The foregoing examples of related art and limitations thereon are illustrative and are not intended to be exhaustive. Other limitations to the related art will become apparent to those of ordinary skill in the art upon reading this specification and viewing the drawings. Summary of the Invention

[0017] In a first aspect, a dual-mode near-field resonant wireless power transfer system is provided, the system configured to simultaneously transmit capacitive power and inductive power according to an adjustable transmission mode ratio at a resonant power signal oscillation frequency, the system comprising: a transmitter subsystem comprising a transmitter antenna subsystem and a power signal tuner module configured to adjust the transmission mode ratio by adjusting a power signal provided to the transmitter antenna subsystem by the power signal tuner module; and a receiver subsystem comprising a receiver antenna subsystem configured to receive power from the transmitter antenna subsystem at the transmission mode ratio.

[0018] The tuner module may be configured to tune a power signal by adjusting a phase difference between a current and a voltage of a power signal provided to the transmitter antenna subsystem. The transmitter subsystem may further comprise a controller and at least one sensor, the controller configured to receive sensor information from the at least one sensor and automatically provide tuning instructions to the power signal tuner module based on the sensor information, and the tuner module configured to adjust a phase difference between a current and a voltage of a power signal provided to the transmitter antenna subsystem in accordance with the tuning instructions.

[0019] The at least one sensor may be disposed on a transmitter subsystem. In other embodiments, the at least one sensor may be located on the receiver subsystem and the controller may be configured to wirelessly receive the sensor information. The at least one sensor may include one of a power load sensor, a transmit power sensor, an ambient object detector, and a distance detector that detects a distance between the transmitter antenna subsystem and the receiver antenna subsystem.

[0020] The resonant power signal oscillation frequency may be free to vary within a predetermined frequency band. The predetermined frequency band may be an Industrial, Scientific and Medical (ISM) frequency band. The system may be detuned to an extent that allows the resonant power signal oscillation frequency to vary within conflicting limits within the predetermined frequency band.

[0021] In a further aspect, a wireless method of bimodally transmitting power according to an adjustable transmission mode ratio at a resonant power signal oscillation frequency is provided, the method including providing a transmitter subsystem including a power signal tuner module and a transmitter antenna subsystem configured to resonate at the resonant power signal oscillation frequency, providing a receiver subsystem including a receiver antenna subsystem configured to resonate at the resonant power signal oscillation frequency, providing a power signal from the tuner module to the transmitter antenna subsystem at the resonant power signal oscillation frequency, adjusting a transmission mode ratio by tuning the power signal from the tuner module to the transmitter antenna subsystem, and receiving at the receiver subsystem the transmitted power at the resonant power signal oscillation frequency via the receiver antenna subsystem at the transmission mode ratio. Adjusting the transmission mode ratio may include adjusting a phase difference between a current and a voltage of the power signal provided to the transmitter antenna subsystem.

[0022] The step of providing the transmitter subsystem may further include providing a controller and at least one sensor, and the adjustment of the current and voltage phase difference may be performed by the tuner module via instructions from the controller based on sensor information received by the controller from at least one sensor. The controller instructions may be automatically issued to the tuner module upon receipt of the sensor information by the controller. The tuner module may automatically execute instructions from the controller to change the phase difference.

[0023] The method may further include allowing the resonant power signal oscillation frequency to vary within a predetermined frequency band, which may be an Industrial, Scientific and Medical (ISM) frequency band. Providing a transmitter subsystem may include providing a transmitter subsystem that is detuned to an extent that allows the resonant power signal oscillation frequency to vary within conflict limits within the predetermined frequency band.

[0024] In a further aspect, a near-field resonant wireless power transfer system is provided, the system comprising: a transmit subsystem including a plurality of substantially mutually isolated transmitter resonators and a corresponding transmitter module in power signal communication with each transmitter resonator, each transmitter module including a transmit controller and a power signal source having a power signal oscillation frequency and a power signal phase, each power signal source controlled by the corresponding transmit controller; one or more receiver subsystems, each including a corresponding receiver resonator; a software look-up table of individual power signal oscillation frequencies enabled for the power signal sources; and software loaded into a memory and executed by a controller of any of the transmitter modules to perform the actions of transmitting one of an input impedance of the corresponding transmitter resonator and a test signal power consumption by the corresponding transmitter resonator, and selecting a frequency from the look-up table for the corresponding power signal source based on one of the input impedance of the corresponding transmitter resonator and the test signal power consumption by the corresponding transmitter resonator. When executed, the software may perform the actions of adjusting a phase of a power signal from the corresponding power signal source while measuring a power value transmitted by the corresponding transmitter resonator. The transmitter resonators may be substantially separated from one another by a grounded shielding grid.

[0025] In a further aspect, a wireless near-field method for transferring power from multiple transmitter subsystems to a single resonant receiver subsystem at variable resonant power signal oscillation frequencies is provided, the method comprising the steps of providing multiple transmitter subsystems comprising a plurality of independent transmitter resonators, each of which can be independently set to one of a plurality of pre-defined power signal oscillation frequencies in a pre-defined frequency band, all of the transmitter resonators having a common transmit surface; positioning a resonant receiver subsystem proximate to the common transmit surface, the resonant receiver subsystem comprising a single receiver resonator overlapping two or more of the transmitter resonators; the step of measuring one of an input impedance of each transmitter resonator and a power consumed by each of the transmitter resonators from a test signal, setting each transmitter resonator of the plurality of mutually independent transmitter resonators to one of a power off state and an activated state based on one of the measured corresponding resonator input impedance and the power consumed by the corresponding transmitter resonator from the test signal, selecting a power signal oscillation frequency for each activated transmitter resonator from among a plurality of pre-set power oscillation frequencies based on the measured input impedance of the activated transmitter resonator, and setting the power signal of each activated transmitter resonator to a corresponding selected frequency. The method may further include adjusting a phase of the power signal applied to each corresponding transmitter resonator to a phase that substantially maximizes power transfer through the transmitter resonator.

[0026] In a further aspect, a wireless near-field method for transmitting power from multiple transmitter subsystems to two or more receiver subsystems at variable resonant power signal oscillation frequencies is provided, the method comprising the steps of providing multiple transmitter subsystems, each of the transmitter subsystems comprising a plurality of independent transmitter resonators, each of the transmitter resonators being independently configurable to one of a plurality of pre-defined power signal oscillation frequencies in a pre-defined frequency band, all of the transmitter resonators having a common transmit surface; and positioning two or more resonant receiver subsystems proximate to the common transmit surface, each of the two or more resonant receiver subsystems comprising a single receiver resonator overlapping two or more of the transmitter resonators. measuring one of an input impedance of each of the transmitter resonators and a power consumed by each of the transmitter resonators from a test signal, setting each transmitter resonator of the plurality of mutually independent transmitter resonators to one of a power off state and an activated state based on the measured corresponding resonator input impedance and one of the power consumed by the corresponding transmitter resonator from the test signal, selecting a power signal oscillation frequency for each activated transmitter resonator from among a plurality of pre-set power oscillation frequencies based on the measured input impedance of the activated transmitter resonator, and setting the power signal of each activated transmitter resonator to a corresponding selected frequency. The method may further include adjusting a phase of the power signal applied to each corresponding transmitter resonator to a phase that substantially maximizes power transfer through the transmitter resonator.

[0027] In a further aspect, a near field wireless system is provided for transmitting power from a photovoltaic cell to a power load, the system comprising: a transmitter module in wired electrical communication with the photovoltaic cell, the transmitter module configured to convert power from the photovoltaic cell into an oscillating power signal having an oscillating frequency; a transmitter resonator in wired electrical communication with the transmitter module and configured to resonate at the oscillating frequency; a receiver resonator configured to resonate at the oscillating frequency and positioned to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction; and a receiver module in wired electrical communication with the receiver resonator, configured to receive power from the receiver resonator and form the received power into a direct current form via wired electrical communication with the power load.

[0028] The transmitter module may comprise a power amplifier configured to adjust the power received from the photovoltaic cell at the oscillation frequency. The transmitter module may comprise an oscillator configured to provide the oscillation frequency to the power amplifier. The transmitter module may comprise a controller and one or more sensors, the controller configured to vary the oscillation frequency based on first information from at least one of the one or more sensors. The transmitter module may comprise a transmit tuning network configured to change at least one phase of the power provided by the transmitter module to the transmitter resonator based on second information from at least one of the one or more sensors under control of the controller.

[0029] The system may include one or more power conditioning units electrically connected between the photovoltaic cell and the transmitter module and configured to adapt power from the photovoltaic cell to a format compatible with the transmitter module. The transmitter module may include small signal electronics, and the power conditioning unit may be further configured to provide power to the small signal electronics. The transmitter resonator may be disposed on a surface of the photovoltaic cell opposite a dynamic solar radiation receiving surface of the photovoltaic cell. The transmitter resonator comprises a surface area having an extent that is at least a major fraction of a dynamic solar radiation receiving surface of the photovoltaic cell.

[0030] Each transmitter resonator may have a planar area that is smaller than a planar area of ​​the receiver resonator. The receiver resonator may be arranged and configured to receive power from the further transmitter resonator via at least one of capacitive coupling and magnetic induction at the resonant frequency.

[0031] In a further embodiment, a near field wireless system is provided for transmitting power from an array of photovoltaic cells to a power load, the system comprising: a first plurality of transmitter modules, each in wired electrical communication with a corresponding photovoltaic cell in the array and configured to convert power from the corresponding photovoltaic cell into an oscillating power signal having an oscillating frequency; a second plurality of transmitter resonators, each in wired electrical communication with a corresponding transmitter module of the first plurality of transmitter modules and configured to resonate at the oscillating frequency; a single receiver resonator configured to resonate at the oscillating frequency and positioned to receive power from the plurality of transmitter resonators via at least one of capacitive coupling and magnetic induction; and a receiver module in wired electrical communication with the receiver resonator, configured to receive power from the receiver resonator and form the received power into a direct current form via wired electrical communication with the power load.

[0032] Each transmitter module of the first plurality of transmitter modules may comprise a power amplifier configured to adjust the power received from the corresponding photovoltaic cell at the oscillation frequency. Each transmitter module of the first plurality of transmitter modules may comprise an oscillator configured to provide the oscillation frequency to the corresponding power amplifier. Each transmitter module of the first plurality of transmitter modules may further comprise a controller and one or more sensors, the controller configured to vary the oscillation frequency based on first information from at least one of the one or more sensors. Each transmitter module of the first plurality of transmitter modules may comprise a transmit tuning network configured to change at least one phase of the power provided by the transmitter module to a corresponding transmitter resonator based on second information from at least one of the one or more sensors under control of a corresponding controller.

[0033] The system may include a third plurality of power conditioning units, each power conditioning unit of the third plurality of power conditioning units electrically connected between a corresponding photovoltaic cell and a corresponding transmitter module and configured to adapt power from the corresponding photovoltaic cell to a format compatible with the corresponding transmitter module. Each transmitter module of the first plurality of transmitter modules may include a small signal electronic circuit, and the corresponding power conditioning unit may be further configured to provide power to the small signal electronic circuit. Each transmitter resonator of the second plurality of transmitter resonators may be disposed on a surface of the corresponding photovoltaic cell opposite a dynamic solar radiation receiving surface of the corresponding photovoltaic cell.

[0034] In a further embodiment, a near field wireless system for transmitting power from an array of photovoltaic cells to a power load is provided, the system comprising: a first plurality of transmitter modules, each transmitter module in wired electrical communication with a corresponding photovoltaic cell in the array and configured to convert power from the corresponding photovoltaic cell into an oscillating power signal having an oscillating frequency; and a second plurality of transmitter resonators, each transmitter resonator in wired electrical communication with a corresponding transmitter module of the first plurality of transmitter modules and configured to resonate at the oscillating frequency. a third plurality of receiver resonators arranged to receive power from a corresponding transmitter resonator of the second plurality of transmitter resonators via at least one of capacitive coupling and magnetic induction; and a fourth plurality of receiver modules, each receiver module in wired electrical communication with a corresponding receiver resonator of the third plurality of receiver resonators, the receiver modules configured to receive power from a corresponding receiver resonator and to form the received power in direct current form via wired electrical communication with the power load.

[0035] Each transmitter module of the first plurality of transmitter modules may comprise a power amplifier configured to adjust the power received from the corresponding photovoltaic cell at the oscillation frequency. Each transmitter module of the first plurality of transmitter modules may comprise an oscillator configured to provide the oscillation frequency to the corresponding power amplifier. Each transmitter module of the first plurality of transmitter modules may further comprise a controller and one or more sensors, the controller configured to vary the oscillation frequency based on first information from at least one of the one or more sensors. Each transmitter module of the first plurality of transmitter modules may comprise a transmit tuning network configured to change at least one phase of the power provided by the transmitter module to a corresponding transmitter resonator based on second information from at least one of the one or more sensors under control of a corresponding controller.

[0036] The system may further comprise a fifth plurality of power conditioning units, each power conditioning unit of the fifth plurality of power conditioning units electrically connected between a corresponding photovoltaic cell in the array of solar cells and a corresponding transmitter module in the first plurality of transmitter modules and configured to adapt power from the corresponding photovoltaic cell into a format compatible with the corresponding transmitter module. Each transmitter module of the first plurality of transmitter modules may comprise a small signal electronic circuit, and the corresponding power conditioning unit of the fifth plurality of power conditioning units may be further configured to provide power to the small signal electronic circuit. Each transmitter resonator of the second plurality of transmitter resonators may be disposed on a surface of a corresponding photovoltaic cell opposite a dynamic solar radiation receiving surface of the corresponding photovoltaic cell in the array of photovoltaic cells.

[0037] In a further embodiment, a near field wireless system for transmitting power from an array of photovoltaic cells to a power load is provided, the system including a first plurality of transmitter modules, each transmitter module in wired electrical communication with a corresponding photovoltaic cell in the array and configured to convert power from the corresponding photovoltaic cell into an oscillating power signal having an oscillating frequency; a second plurality of transmitter resonators, each transmitter resonator in wired electrical communication with a corresponding transmitter module of the first plurality of transmitter modules and configured to resonate at the oscillating frequency; and a number of transmitter resonators greater than the number of transmitter resonators. a third plurality of receiver resonators configured to resonate at least one of the oscillation frequency and the third plurality of receiver resonators configured to receive power from a portion of the plurality of transmitter resonators via at least one of capacitive coupling and magnetic induction, and a fourth plurality of receiver modules, each receiver module in wired electrical communication with a corresponding receiver resonator, the receiver modules configured to receive power from the corresponding receiver resonator and to form the received power in direct current form via wired electrical communication with the power load.

[0038] Each transmitter module of the first plurality of transmitter modules may comprise a power amplifier configured to adjust the power received from the corresponding photovoltaic cell at the oscillation frequency. Each transmitter module of the first plurality of transmitter modules may comprise an oscillator configured to provide the oscillation frequency to the corresponding power amplifier. Each transmitter module of the first plurality of transmitter modules may further comprise a controller and one or more sensors, the controller configured to vary the oscillation frequency based on first information from at least one of the one or more sensors. Each transmitter module of the first plurality of transmitter modules may comprise a transmit tuning network configured to change at least one phase of the power provided by the transmitter module to a corresponding transmitter resonator based on second information from at least one of the one or more sensors under control of a corresponding controller.

[0039] The system may include a fifth plurality of power conditioning units, each power conditioning unit of the fifth plurality of power conditioning units electrically connected between a corresponding photovoltaic cell in the array of solar cells and a corresponding transmitting module in the first plurality of transmitting modules and configured to adapt power from the corresponding photovoltaic cell into a format compatible with the corresponding transmitting module.

[0040] Each transmitter module of the first plurality of transmitter modules may comprise a small signal electronic circuit, and a corresponding power conditioning unit of the fifth plurality of power conditioning units may be further configured to provide power to the small signal electronic circuit. Each transmitter resonator of the second plurality of transmitter resonators may be disposed on a surface of a corresponding photovoltaic cell opposite a dynamic solar radiation receiving surface of the corresponding photovoltaic cell in the array of photovoltaic cells.

[0041] In a further aspect, a method of transmitting power from a photovoltaic cell to a power load is provided, the method including converting power from the photovoltaic cell into an oscillating power signal having an oscillating frequency in a transmitting module, transmitting the power to a transmitter resonator in wired electrical communication with the transmitting module and configured to resonate at the oscillating frequency, receiving the power at a receiver resonator configured to resonate at the oscillating frequency and positioned to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction, receiving the power in a receiver module in wired electrical communication with the receiver resonator, and converting the received power into a direct current form via wired electrical communication with the electrical load.

[0042] In a further embodiment, a method for transmitting power from an array of photovoltaic cells to a power load is provided, the method including: converting, in each transmitting module of a first plurality of corresponding transmitting modules, power from each photovoltaic cell in the array into an oscillating power signal having an oscillating frequency; transmitting the power of each transmitting module of the transmitting modules to a corresponding transmitter resonator from a second plurality of transmitter resonators, each resonator configured to resonate at the oscillating frequency; receiving power at a receiver resonator configured to resonate at the oscillating frequency and arranged to receive power from the plurality of transmitter resonators via at least one of capacitive coupling and magnetic induction; receiving the power in a receiver module in wired electrical communication with the receiver resonator; and converting the received power into a direct current form via wired electrical communication with the electrical load.

[0043] In a further embodiment, a method for transmitting power from an array of photovoltaic cells to a power load is provided, the method including: converting, in each transmitting module of a first plurality of corresponding transmitting modules, power from each photovoltaic cell of the array into an oscillating power signal having an oscillating frequency; transmitting power from each transmitting module of the transmitting modules to a corresponding transmitter resonator among a second plurality of transmitter resonators, each transmitter resonator configured to resonate at the oscillating frequency; receiving power from each transmitter resonator in a corresponding receiver resonator configured to resonate at the oscillating frequency, each receiver resonator further configured and arranged to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction; receiving power from each receiver resonator in a corresponding receiver module in wired electrical communication with the receiver resonator; and converting the received power into a direct current form via wired electrical communication with the electrical load.

[0044] In a further embodiment, a method for transmitting power from an array of photovoltaic cells to a power load is provided, the method comprising: converting, in each transmitting module of a first plurality of corresponding transmitting modules, power from each photovoltaic cell in the array into an oscillating power signal having an oscillating frequency; transmitting the power from each transmitting module of the transmitting modules to one transmitter resonator from a second plurality of transmitter resonators, each transmitter resonator configured to resonate at the oscillating frequency; receiving the power from each transmitter resonator in any nearby receiver resonator from a third plurality of receiver resonators configured to resonate at the oscillating frequency, each receiver resonator further configured and arranged to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction; sharing the received power among the third plurality of receiver resonators; and converting the received power into a direct current form from one or more of the third plurality of receiver resonators via one or more corresponding receiver modules via wired electrical communication with the power load. The method may further include converting the voltage and current of the power from each photovoltaic cell to a voltage and current that is adapted to a corresponding transmission module prior to converting the power into an oscillating power signal.

[0045] A power transfer system for supplying power from a DC power source to a power load is provided, the power transfer system comprising: a radio frequency power amplifier in wired electrical communication with the power source and configured to convert a DC voltage from the power source to an AC voltage signal having an oscillating frequency; an adjustable phase radio frequency rectifier in wired electrical contact with the power load and in radio frequency communication with the power amplifier, the rectifier configured to receive power transmitted from the power amplifier; and a receiver controller in communication with the rectifier, the receiver controller configured to adjust an efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier. The rectifier may be a differential self-synchronous radio frequency rectifier.

[0046] The receiver controller may be configured to automatically adjust the current-voltage phase characteristics of the rectifier. The power transfer system may further include a load management system in wired communication with the power load and disposed in a power signal direction between the power load and the rectifier, the load management system configured to increase efficiency of power transfer by adjusting an input impedance of the rectifier. The load management system may be configured to automatically adjust the input impedance of the rectifier.

[0047] The power transfer system may further include a transmitter controller in communication with the power amplifier, the transmitter controller configured to increase efficiency of power transfer by adjusting a current-voltage phase characteristic of the power amplifier. The transmitter controller may be configured to automatically adjust the current-voltage phase characteristic of the power amplifier to increase efficiency of power transfer.

[0048] The power transfer system may further comprise an oscillator in communication with the power amplifier and the transmitter controller, the transmitter controller may be configured to adjust the oscillation frequency with the oscillator.

[0049] The power amplifier may be in direct wired radio frequency communication with the rectifier. The power amplifier may be in wireless near-field radio frequency communication with the adjustable phase radio frequency rectifier. The power transfer system may include a transmitter resonator in wired radio frequency communication with the power amplifier and a receiver resonator in wired radio frequency communication with the rectifier. The transmitter resonator and the receiver resonator may be in wireless near-field radio frequency communication with each other. The power amplifier may be in communication with the rectifier in at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. The power amplifier may be in two-way near-field wireless radio frequency communication with the rectifier.

[0050] The DC power source may comprise a rechargeable battery and the power load may comprise an electric motor. The load may comprise a computer monitor. A resonant structure of the system may include at least one electrically conductive mechanical load supporting structural component of the system.

[0051] The system may further include a power conditioning unit electrically disposed between the power source and the power transmission system, the power conditioning unit configured to adjust at least one of a current and a voltage from the power source to improve efficiency of power transmission.

[0052] There is further provided a method of power transfer from a DC power source to a power load, the method comprising the steps of providing a power transfer system in wired electrical communication with the power source, the power transfer system comprising an adjustable phase radio frequency rectifier in wired electrical contact with the power load and a radio frequency power amplifier in radio frequency communication, converting power from the DC power source to a radio frequency oscillating power signal in the power amplifier, converting the radio frequency oscillating power signal in the rectifier to a DC power signal, and adjusting the efficiency of the power transfer by adjusting the current-voltage phase characteristics of the rectifier. Providing the adjustable phase radio frequency rectifier may include providing a differential self-synchronous radio frequency rectifier.

[0053] The method may further include adjusting an efficiency of power transfer by adjusting a DC equivalent input resistance of the power amplifier. The step of providing the power transfer system may include providing a load management system in wired communication with the rectifier and the power load. Adjusting the DC equivalent input resistance of the power amplifier may include adjusting an input impedance of the rectifier by adjusting the load management system. Adjusting the load management system may include automatically adjusting the load management system.

[0054] The method may further include adjusting efficiency of power transfer by adjusting a current-voltage phase characteristic of the power amplifier. The step of providing the power transfer system may include providing a transmitter controller in communication with the power amplifier for controlling the power amplifier. The adjustment of the current-voltage phase characteristic of the power amplifier may be performed by the transmitter controller. The adjustment of the current-voltage phase characteristic of the power amplifier may be performed automatically by the transmitter controller.

[0055] The method may further include adjusting efficiency of power transfer by varying an oscillation frequency of the power amplifier.

[0056] The step of providing the power transfer system may include providing a receiver controller in communication with the rectifier for controlling the rectifier. Adjustment of the current-voltage phase characteristics of the rectifier may be performed by the receiver controller. Adjustment of the current-voltage phase characteristics of the rectifier may be performed automatically by the receiver controller.

[0057] The step of providing the power transfer system may include providing a power amplifier in direct wired radio frequency communication with the adjustable phase radio frequency rectifier.The step of providing the power transfer system may include providing a power amplifier in wireless near field radio frequency communication with the adjustable phase radio frequency rectifier.

[0058] The step of providing the power transfer system may include providing a transmitter resonator in wired radio frequency communication with the power amplifier and a receiver resonator in wired radio frequency communication with the radio frequency rectifier. The method may further include operating the transmitter resonator and the receiver resonator in wireless near-field radio frequency communication with each other. The step of providing the power transfer system may include providing a power amplifier in communication with the rectifier in at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. The step of providing the power transfer system may include providing a power amplifier in two-way near-field wireless communication with the rectifier.

[0059] The method may further include providing a power conditioning unit electrically disposed between the power source and the power transmission system, and adjusting the power conditioning unit to adjust at least one of a current and a voltage from the power source to improve efficiency of power transmission.

[0060] A method of transmitting power from a DC power source to a power load is provided, the method including the steps of providing a power transmission system in wired electrical communication with the power source, the power transmission system including an oscillator capable of oscillating at an oscillating frequency, a power amplifier and a transmitter tuning network under the control of a transmitter controller, and a receiver tuning network and a load management system under the control of a receiver controller, the load management system being in wired electrical communication with the power load; converting power from the power source in the power amplifier into an oscillating power signal having an oscillating frequency; transmitting the power signal from the power amplifier to the load management system via the transmitter tuning network and the receiver tuning network under control of the transmitter controller; adjusting at least one of the oscillating frequency, the input DC equivalent resistance of the power amplifier, the transmitter tuning network, the receiver tuning network, and the load management system to change a power transfer rate; and placing the power received by the load management system in a direct current form via wired electrical communication with a power load.

[0061] Transmitting the power signal through the transmitter tuning network and the receiver tuning network may include transmitting power by wired communication. Transmitting the power signal through the transmitter tuning network and the receiver tuning network may include transmitting power by wireless communication. Transmitting power by wireless communication may include transmitting power by near-field wireless communication. Transmitting power by near-field wireless communication may include transmitting power by at least one of capacitive coupling and inductive coupling.

[0062] The transfer of power from the DC power source may include transferring power from at least one solar cell. The transfer of power from the DC power source may include transferring power from at least one solar battery. The transfer of power from the DC power source may include transferring power from a power source with a fluctuating voltage.

[0063] In another embodiment, a motorized system is provided, the motorized system comprising a mechanical load support structure having a first portion that is electrically conductive, a power load, and a power transfer system comprising at least one radio frequency resonator configured for near-field wireless power transfer, the resonator having an at least partially electrically conductive first portion. The motorized system may further comprise a rechargeable battery, and the power load may comprise an electric motor. The motorized system may be an electric vehicle, and the mechanical load support structure may comprise a chassis of the electric vehicle. The motorized system may be a display monitor, and the mechanical load support structure may be at least one of a frame and a base of the display monitor.

[0064] The electrical power system may further comprise a power source. The power transfer system may comprise a radio frequency power amplifier in wired electrical communication with the power source and configured to convert a DC voltage from the power source to an AC voltage signal having an oscillating frequency, an adjustable phase radio frequency rectifier in wired electrical contact with the power load and in radio frequency communication with the power amplifier, the rectifier configured to receive power transmitted from the power amplifier, and a receiver controller in communication with the rectifier, the receiver controller configured to adjust an efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier.

[0065] In another embodiment, an apparatus is provided comprising: a mechanical load supporting structure having a conductive first portion; a power source; a power load; and a power transmission system comprising: a radio frequency power amplifier in wired electrical communication with the power source and configured to convert a direct current voltage from the power source to an alternating current voltage signal having an oscillating frequency; an adjustable phase radio frequency rectifier in wired electrical contact with the power load and in radio frequency communication with the power amplifier, the rectifier configured to receive power transmitted from the power amplifier; and a receiver controller in communication with the rectifier, the receiver controller configured to adjust an efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier;

[0066] The apparatus may further comprise a load management system in wired communication with the power load and disposed in a power signal direction between the power load and the rectifier, the load management system configured to increase efficiency of power transfer by adjusting an input impedance of the rectifier. The apparatus may further comprise a transmitter controller in communication with the power amplifier, the transmitter controller configured to increase efficiency of power transfer by adjusting a current-voltage phase characteristic of the power amplifier. The apparatus may further comprise an oscillator in communication with the power amplifier and the transmitter controller, the transmitter controller configured to adjust the oscillation frequency with the oscillator.

[0067] The power amplifier may be in direct wired radio frequency communication with the rectifier via a first portion that is conductive. The power amplifier may be in wireless near-field radio frequency communication with the rectifier. The power transfer system may include a transmitter resonator in wired radio frequency communication with the power amplifier and a receiver resonator in wired radio frequency communication with the rectifier, one of the transmitter resonator and the receiver resonator may include the first portion that is conductive. The transmitter resonator and the receiver resonator may be in wireless near-field radio frequency communication with each other. The power amplifier may be in communication with the rectifier in at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. The power amplifier may be in two-way near-field wireless radio frequency communication with the rectifier. The DC power source may include a rechargeable battery and the power load may include an electric motor.

[0068] Exemplary embodiments are illustrated in the referenced drawings, in which: It is intended that the embodiments and drawings disclosed herein be considered illustrative and not restrictive. [Brief description of the drawings]

[0069] [Figure 1] 1 is a schematic diagram of a wireless power transmission system according to an example embodiment. [Figure 2A] Various example embodiments depict antennas that can be used by themselves or in combination with other elements disclosed. [Figure 2B] Various example embodiments depict antennas that can be used by themselves or in combination with other elements disclosed. [Figure 2C] Various example embodiments depict antennas that can be used by themselves or in combination with other elements disclosed. [Figure 3A] 1 illustrates a side projection view of an antenna that may be used by itself or in combination with other disclosed elements in various example embodiments. [Figure 3B] 1 illustrates a side projection view of an antenna that may be used by itself or in combination with other disclosed elements in various example embodiments. [Figure 4A] 1 illustrates a side projection view of one example of a resonator that may be used by itself or in combination with other disclosed elements in various example embodiments. [Figure 4B] 1 illustrates a side projection view of one example of a resonator that may be used by itself or in combination with other disclosed elements in various example embodiments. [Figure 4C] 1 illustrates a side projection view of one example of a resonator that may be used by itself or in combination with other disclosed elements in various example embodiments. [Figure 4D] 1 illustrates a side projection view of one example of a resonator that may be used by itself or in combination with other disclosed elements in various example embodiments. [Diagram 5] 1 illustrates a cross-sectional view of one example of a resonator that may be used by itself or in combination with other disclosed elements in various example embodiments. [Figure 6] 1 is a schematic diagram of a primary side of a wireless power transfer system according to an example embodiment. FIG. [Figure 7] FIG. 2 is a schematic diagram of a secondary side of a wireless power transfer system according to an example embodiment. [Figure 8] FIG. 1 is a schematic diagram of a typical power amplifier that may be used in various example embodiments, either by itself or in combination with other disclosed elements. [Figure 9] FIG. 2 is a schematic diagram of an exemplary self-synchronous rectifier that may be used in various example embodiments by itself or in combination with other disclosed elements. [Figure 10] 7 illustrates a detailed schematic diagram of the V / I tuner of FIG. 6 used to tune a power signal to a transmitter resonator according to an example. [Figure 11] 1 is a flow chart of a near-field resonant wireless method for bimodal power transmission with adjustable transmission mode ratios at a resonant power signal oscillation frequency according to an example embodiment. [Figure 12] FIG. 1 is a schematic diagram of a multiple transmitter near-field resonant wireless power transfer system for transferring power to a single receiver subsystem. [Figure 13A] 1 illustrates a multiple transmitter near-field resonant wireless power transfer system for transferring power to a single receiver subsystem. [Figure 13B] 1 illustrates a multiple transmitter near-field resonant wireless power transfer system for transferring power to a single receiver subsystem. [Figure 14] 1 illustrates a multiple-transmitter near-field resonant wireless power transfer system for transmitting power to more than one receiver subsystem. [Figure 15] 1 shows a flow chart of a wireless near-field method for transferring power from multiple transmitter subsystems to a single resonant receiver subsystem with variable resonant power signal oscillation frequency. [Figure 16] 13 shows a flow chart of another wireless near-field method for transferring power from multiple transmitter subsystems to a single resonant receiver subsystem with variable resonant power signal oscillation frequency. [Figure 17] 1 shows a flow chart of a wireless near-field method for transmitting power from multiple transmitter subsystems to more than one resonant receiver subsystem at variable resonant power signal oscillation frequencies. [Figure 18] 13 shows a flow chart of another wireless near-field method for transmitting power from multiple transmitter subsystems to more than one resonant receiver subsystem at variable resonant power signal oscillation frequencies. [Figure 19A] A near-field resonant wireless power transfer system is presented for wirelessly transferring power from a solar cell to a power load. [Figure 19B] 1 shows a power transfer system for wirelessly transferring power from a solar cell to a power load. [Figure 20A] FIG. 19B shows a front view of a solar cell array configured to use the near-field resonant wireless power transfer system of FIG. 19A in a many-to-one configuration. [Figure 20B]FIG. 19B shows a rear view of a solar cell array configured to use the near-field resonant wireless power transfer system of FIG. 19A in a many-to-one configuration. [Figure 21A] FIG. 19B shows a front view of a solar cell array configured to use the near-field resonant wireless power transfer system of FIG. 19A in a one-to-one configuration. [Figure 21B] FIG. 19B shows a rear view of a solar cell array configured to use the near-field resonant wireless power transfer system of FIG. 19A in a one-to-one configuration. [Figure 22A] FIG. 19B shows a front view of a solar cell array configured to use the near-field resonant wireless power transfer system of FIG. 19A in a row-based configuration. [Figure 22B] FIG. 19B illustrates a rear view of a solar cell array configured to use the near-field resonant wireless power transfer system of FIG. 19A in a row-based configuration. [Figure 23] 1 shows a flowchart of a method for wirelessly transmitting power from a solar cell to a power load. [Figure 24] 1 shows a flowchart diagram of another method for wirelessly transmitting power from a photovoltaic array to a power load. [Diagram 25] 1 shows a flowchart diagram of another method for wirelessly transmitting power from a photovoltaic array to a power load. [Figure 26] 1 shows a flowchart diagram of another method for wirelessly transmitting power from a photovoltaic array to a power load. [Figure 27A] 1 shows a diagram of a portion of an electric vehicle that uses an embodiment of a power transfer system. [Figure 27B] 2 illustrates another view of a portion of an electric vehicle using an embodiment of a power transfer system. [Figure 28A] FIG. 1 illustrates a diagram of a computer monitor using an embodiment of a power transfer system. [Figure 28B] 1 illustrates a computer monitor using another embodiment of a power transfer system. [Figure 29]1 shows a flow chart of a method for transferring power from a DC power source to a power load. [Diagram 30] 4 shows a flow chart of another method for transferring power from a DC power source to a power load. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0070] Throughout the following description, specific details are set forth to enable those skilled in the art to more fully understand. However, well-known elements may not be shown or described in detail so as not to unnecessarily obscure the present disclosure. Therefore, the description and drawings should be regarded in an illustrative sense rather than a restrictive sense.

[0071] One aspect of the invention provides a wireless power transmission system comprising a transmitter (also referred to as a primary side) and a receiver (also referred to as a secondary side). Another aspect of the invention provides a wireless power transmitter that may be utilized as part of other wireless power transmission systems. Another aspect of the invention provides a wireless power receiver that may be utilized as part of other wireless power transmission systems. A transmitter according to some embodiments of the invention may comprise a resonator configured to transmit power by inductive power transmission and / or by capacitive power transmission. Similarly, a receiver according to some embodiments of the invention may include a resonator configured to receive power by inductive power transmission and / or by capacitive power transmission.

[0072] 1 is a simplified schematic diagram of a wireless power transfer (WPT) system (10) including a primary side (12) and a secondary side (14). The primary side (12) may also be referred to as a transmitter, and the secondary side (14) may also be referred to as a receiver. The primary side (12) includes a transmitter module (20) and a transmitter resonator (30), and the secondary side (14) includes a receiver module (40) and a receiver resonator (50).

[0073] The transmitter module 20 receives power, including, for example, direct current (DC) power, as an input. Although not shown, the transmitter module 20 may include, for example, an inverter, a transmit compensation network, and / or other components as further described herein. The transmitter module 20 delivers power, including, for example, alternating current (AC) power, as an output to the transmitter resonator 30.

[0074] The transmitter resonator (30) may receive power from the transmitter module (20) as an input and output a magnetic field (31A) (e.g., a time-varying magnetic field) and / or an electric field (31B) (e.g., a time-varying electric field). In some embodiments, the transmitter resonator (30) outputs a magnetic field (31A) for an IPT. In some embodiments, the transmitter resonator (30) outputs an electric field (31B) for a CPT. In some embodiments, the resonator (30) outputs the magnetic field (31A) and the electric field (31B) simultaneously to transmit power via the CPT and the IPT simultaneously. In some embodiments, the resonator (30) can be switched between outputting the electric field (31B) for the CPT, outputting the magnetic field (31A) for the IPT, and outputting the magnetic field (31A) and the electric field (31B) simultaneously to transmit power via the CPT and the IPT simultaneously.

[0075] In the presence of a magnetic field (31A), a current may be induced in the receiver resonator (50) due to IPT. In the presence of an electric field (31B), an alternating potential may be induced on the receiver resonator (50) (or its antenna(s).

[0076] When a current is induced in the receiver resonator (50) by the magnetic field (31A), such current may be output to the receiver module (40). Similarly, when an alternating potential is induced on the receiver resonator (50) by the electric field (31B), a current may be driven by the receiver resonator (50) into the receiver module (40).

[0077] The receiver module (40) may receive power (e.g., AC power) from the receiver resonator (50) as an input and may output power (e.g., DC power) to a load. The load may be a charge for a power storage device such as a battery or a supercapacitor. As a non-limiting example, the load may include or be an element of an electric bicycle (also called an e-bicycle or e-bike), such as an e-bike that is part of a bike-share fleet, a car, a boat, etc. Although not shown, the receiver module (40) may include a rectifier, a receive compensation network, and / or other components as further described herein.

[0078] The WPT system (10) may be configured to adjust the ratio of power transmitted from the transmitter module (20) to the receiver module (40) via CPT to the power transmitted by the transmitter module (20) to the receiver module (40) via IPT (the "transmission mode ratio") for a variety of reasons. For example, the transmission mode ratio may be adjusted to increase the percentage of power delivered by CPT when the distance between the transmitter resonator (30) and the receiver resonator (50) increases; to increase the percentage of power delivered by IPT when a living being (e.g., a human or animal) is within the proximity of the WPT system (10); to increase the percentage of power delivered by CPT when an object (e.g., a metal object) is within the proximity of the WPT system (10); to increase the percentage of power delivered by CPT when the alignment between the transmitter resonator (30) and the receiver resonator (50) deteriorates; and / or any combination of the foregoing.

[0079] In some embodiments, the transmission mode ratio may be adjusted according to a maximum power point tracking technique, such as, but not limited to, the "observe and perturb" sometimes utilized in wind turbines and solar panels (see, e.g., S. Dehghani, S. Abbasian and T. Johnson, "Adjustable Load With Tracking Loop to Improve RF Rectifier Efficiency Under Variable RF Input Power Conditions," in IEEE Transactions on Microwave Theory and Techniques, vol. 64, no. 2, pp. 343-352, Feb. 2016). In some embodiments, the transmission mode ratio may be adjusted according to a machine-learned algorithm. For example, in some embodiments, if the WPT system (10) determines that the WPT efficiency is unnecessarily low, the WPT system (10) increases the proportion of power delivered by CPT (or IPT). If increasing the reliance on CPT (or IPT) adversely affects WPT efficiency, the WPT system (10) may decrease the reliance on CPT (or IPT). This process may be repeated iteratively until a desired / maximum WPT efficiency is reached.

[0080] The transmitter resonator (30) and receiver resonator (50) may each include multiple antennas (80) arranged in various configurations.

[0081] The antenna (80) may include any suitable antenna having high self-inductance and high self-capacitance capable of producing (individually and / or simultaneously) both the magnetic field (31A) and the electric field (31B) for CPT and IPT. Figures 2A, 2B, and 2C depict non-limiting examples of antennas (80), (180), (280). For purposes herein, "high self-inductance" is a self-inductance that is large enough such that the antenna can generate a magnetic field that is suitable for IPT. Similarly, for purposes herein, "high self-capacitance" is a self-capacitance that is large enough such that the antenna can generate an electric field that is suitable for CPT.

[0082] FIG. 2A illustrates an antenna (80) according to an embodiment of the present invention. The antenna (80) may include any suitable conductive material. For example, the antenna (80) may include copper, gold, silver, aluminum, other suitable materials, or combinations thereof. As can be seen in FIG. 2A, the antenna (80) includes an elongated element (80A) having a rectangular (e.g., square) cross-section that is bent or formed into the shape of a generally planar rectangular (XY plane) coil such that adjacent turns of the elongated element (80A) are separated by a gap (80B). The gap (80B) is depicted as being generally constant along the length of the elongated element (80), although this is not required.

[0083] To increase the self-inductance of antenna 80, the size of gap 80B may be decreased. To increase the self-capacitance of antenna 80, the number of bends (e.g., bends 82A) in elongated element 80A may be increased, the number of corners and edges (e.g., edges 82B) in elongated element 80A may be increased, the length of elongated element 80A may be increased, and / or the thickness (80C) of elongated element 80A may be increased.

[0084] 2B shows another non-limiting example of an antenna (180) according to another embodiment of the present invention. The antenna (180) is substantially similar to the first antenna (80), except that the elongated element (180A) is bent or formed into a generally planar zigzag shape with square corners, as shown in FIG. 2B, instead of being bent or formed into a generally planar rectangular coil shape. As in antenna (80), adjacent zigs or zags of the elongated element (180A) are separated by gaps (180B). The gaps (180B) are depicted as generally constant along the length of the elongated element (180), although this is not required.

[0085] To increase the self-inductance of antenna 180, the size of gap 180B may be decreased. To increase the self-capacitance of antenna 180, the number of bends (e.g., bends 182A) in elongated element 180A may be increased, the number of corners and edges (e.g., edges 182B) in elongated element 180A may be increased, and / or the thickness 180C of elongated element 180A may be increased.

[0086] 2C shows another non-limiting example of an antenna (280) according to another embodiment of the invention. The antenna (280) is substantially similar to the first antenna (80), except that instead of the elongated element (280A) being bent or formed into a generally planar rectangular coil shape, the sector elements (280C) are bent or formed into a generally planar circular shape (in the XY plane) having a hub element (280A) extending radially outwardly. Adjacent sector elements (280C) are separated from each other by a gap (280B).

[0087] To increase the self-inductance of the antenna (280), the size of the gap (280B) may be decreased. To increase the self-capacitance of the antenna (280), the number of sectors (280C) may be increased, the number of corners and edges (e.g., edges (282A)) of the hub (280A) and / or sectors (280C) may be increased, and / or the thickness (280C) of the elongated hub (280A) and / or sectors (280C) may be increased.

[0088] 2A, 2B, and 2C show exemplary non-limiting embodiments of antennas (80), (180), and (280), it will be understood that many other shapes and configurations of suitable antennas (80) may be utilized with the resonators described herein. Non-limiting examples of modifications that may be made to the shown antennas include changing the cross-sectional shape of elongated elements (80A), (180A) to something other than rectangular (e.g., triangular, circular, hexagonal, etc.), changing the 90° bends (82A), (182A) to something other than 90° or rounded, or changing the XY plane shape of first transmitter antenna (80) to something other than rectangular or circular with non-repeating patterns such as bends and corners.

[0089] Although the antennas (80), (180), (280) are described and shown herein as being relatively flat or planar (e.g., having substantially no thickness variation in the Z direction), this is not required. In some embodiments, the antennas (80), (180), (280) may have a conical concave or conical convex shape as shown in Figures 3A and 3B. For example, the antennas herein have a conical helical shape (not shown). In some embodiments, the antenna (80) has a rectangular conical helical shape such that the inner winding of the antenna (80) separates from the outer winding of the antenna (80) in the Z direction. Such a conical shape allows the use of a resonator with a wider range of resonant frequencies. In other embodiments, the thickness of the first transmitter antenna in the Z direction may vary in other ways.

[0090] The antennas (80), (180), (280) may be arranged in a configuration similar to that of the plates of a CPT WPT system, for example. For example, in a two-antenna WPT system according to an embodiment of the present invention, the transmitter resonator (30) may include a first transmitter antenna (32) arranged in parallel to a first receiver antenna (52) of the receiver resonator (50), as shown in FIG. 4A. For CPT, the mutual capacitance between the two antennas (32) and (52) provides a path for current to flow forward to the receiver, and a conductive path (e.g., ground) allows current to flow back to the transmitter. For IPT, carrying a current through the first transmitter antenna (32) creates a magnetic field (31A) that can induce a current in the first receiver antenna (52). For CPT, a voltage can be applied to the first transmitter antenna (32) to create a potential difference between the first transmitter antenna (32) and the first receiver antenna (52), thereby creating an electric field (31B).

[0091] The first transmitter antenna (32) may comprise any suitable antenna having high self-inductance and high self-capacitance capable of producing both a magnetic field (31A) and an electric field (31B) (individually and / or simultaneously). For example, the first transmitter antenna may include one of antennas (80), (180), (280), or any other antenna described herein.

[0092] The first receiver antenna (52) may include any suitable antenna having high self-inductance and high self-capacitance, which can have a current induced therein by the magnetic field (31A) and can have a potential difference thereon due to the electric field (31B) (individually and / or simultaneously). In some embodiments, the first receiver antenna (52) may be substantially similar to the first transmitter antenna (32) (e.g., the first receiver antenna (52) may have the same characteristics as any of the antennas described or shown herein or otherwise). In some embodiments, the antennas (32), (52) may be different from each other (e.g., the first transmitter antenna (32) may include antenna (80) and the first receiver antenna (52) may include antenna (180).

[0093] In some embodiments, the XY plane area of ​​the first transmitter antenna (32) is smaller than the XY plane area of ​​the first receiver antenna (52) to improve coupling between the first transmitter antenna (32) and the first receiver antenna (52).

[0094] Figure 4B shows another embodiment of the configuration of antennas (80), (180), (280). In particular, Figure 4B shows a four stacked antenna (or four perpendicular antenna) WPT system. The transmitter resonator (130) and the receiver resonator (150) each include two antennas. One antenna of the transmitter resonator (30) and one antenna of the receiver resonator (150) together provide a forward path for power, and the other antenna of the transmitter resonator (130) and the other antenna of the receiver resonator (150) together provide a reverse path for power.

[0095] For IPT, carrying a current through the transmitter antennas (132), (134) creates a magnetic field that can induce a current in the first and second receiver antennas (152), (154). For CPT, applying a potential difference between the first and second antennas (132), (134) creates an electric field (shown as 31B in FIG. 1 ) that can induce a potential across the first and second receiver antennas (152), (154).

[0096] As shown in FIG. 4B, the transmitter resonator (130) comprises a first transmitter antenna (132) and a second transmitter antenna (134) separated in the Z direction by a spacer (138).

[0097] The first transmitter antenna (132) may include any suitable antenna having high self-inductance and high self-capacitance, which is capable of generating (individually and / or simultaneously) both the magnetic field (31A) and the electric field (31B). For example, the first transmitter antenna may include any one of antennas (80), (180), (280), or any other antenna described herein.

[0098] The spacer (138) may include any suitable material. For example, the spacer (138) may include air, a dielectric material, a ferrite, or some combination thereof. The spacer (138) may have a permittivity constant selected to alter the electric field (31A) and / or may have a permeability constant selected to alter the magnetic field (31B). The spacer (138) may include a high permittivity material that increases the capacitance of the transmitter resonator (130). The thickness and planar area of ​​the spacer (138) may depend on the thickness and / or planar area of ​​the first transmitter antenna (132) and the second transmitter antenna (134). In some embodiments, electrical isolation may be desired and a low permittivity material may be utilized for the spacer (138) (e.g., for shielding).

[0099] The second transmitter antenna (134) may comprise any suitable antenna having high self-inductance and high self-capacitance, which can generate (individually and / or simultaneously) the magnetic field (31A) and the electric field (31B). In some embodiments, the second transmitter antenna (134) may be substantially similar to the first transmitter antenna (132) (e.g., the second transmitter antenna (134) may have the same characteristics as any of the antennas described or shown herein or otherwise). In some embodiments, the first transmitter antenna (132) and the second transmitter antenna (134) and the first receiver antenna (152) and the second receiver antenna (154) may be different from each other (e.g., the first transmitter antenna (132) and the second transmitter antenna (134) may be similar to the first transmitter antenna (132) and the second receiver antenna (152) and the second receiver antenna (154) may be similar to the antenna (180).

[0100] In some embodiments, the XY-plane area of ​​the second transmitter antenna (134) may be of a different size than the XY-plane area of ​​the first transmitter antenna (132). In some embodiments, to ensure coupling between each pair of antennas, the XY-plane area of ​​the second transmitter antenna (134) may be smaller than the XY-plane area of ​​the first transmitter antenna (132). In some embodiments, the XY-plane area of ​​the second transmitter antenna (134) may be larger than the XY-plane area of ​​the first transmitter antenna (132).

[0101] In some embodiments, the second transmitter antenna (134) is substantially complementary in size and / or shape to the first antenna (132), such that the first transmitter antenna (132) does not substantially overlap the second transmitter antenna (134) in the Z direction. Figure 5 depicts a schematic diagram of an XZ-plane cross section of a portion of a transmitter resonator (130), in which the first transmitter antenna (132) and the second transmitter antenna (134) are each formed substantially like the first transmitter antenna (180) of Figure 2B. As described above, the portions (132A-1), (132A-2), and (132A-3) of the elongated element (132A) of the first transmitter antenna (132) overlap in the Z direction with the gaps (134B-1), (134B-2), and (134B-3) of the second transmitter antenna (134) (e.g., a line oriented in the Z direction passing through the portion (132A-1) of the elongated element (132A) of the first antenna (132) passes through the gap (134B-1) of the second antenna (134). ), and portions (134A-1), (134A-2), (134A-3) of the elongated element (134A) of the second transmitter antenna (134) overlap in the Z direction with the gaps (132B-1), (132B-2), (132B-3) of the first transmitter antenna (132) (e.g., a line oriented in the Z direction passing through portion (134A-1) of the elongated element (134A) of the second antenna (134) passes through gap (132B-1) of the second antenna (134). The complementary shapes of the first transmitter antenna (132) and the second antenna (134) can reduce parasitic energy losses experienced by the transmitter resonator (130). In some embodiments, the first transmitter antenna (132) and the second transmitter antenna (134) may not be perfectly complementary, but may have one or more complementary portions.

[0102] The receiver resonator (150) includes a first receiver antenna (152) and a second receiver antenna (154) separated in the Z direction by a spacer (158). The first receiver antenna (152) may be substantially similar to antennas (80), (180), (280), or any of those described herein. The second receiver antenna (154) may be substantially similar to antennas (80), (180), (280), or any of those described herein. Like the first transmitter antenna (132) and the second transmitter antenna (134), the first receiver antenna (152) and the second receiver antenna (154) may be complementary (or partially complementary) in size and / or shape.

[0103] In some embodiments, the XY-plane areas of the first receiver antenna (152) and the second receiver antenna (154) are different from the XY-plane areas of the first and second transmitter antennas shown in FIG. 4B to adjust the self-inductance or self-capacitance of the receiver resonator (150). For example, in some embodiments, the XY-plane areas of the first receiver antenna (152) and the second receiver antenna (154) may be larger than the XY-plane areas of the first transmitter antenna (132) and the second transmitter antenna (134) shown in FIG. 2A. Such a difference in the XY-plane areas may improve the ability of the receiver resonator (150) to capture more of the magnetic field (31A) and / or the electric field (31B).

[0104] The spacer (158) may include any suitable spacer. The spacer (158) may include the same or similar material as the spacer (138) or a different material than the spacer (138). Compared to the spacer (158), the spacer (138) may have a smaller Z dimension to achieve a desired self-capacitance and / or self-inductance. This may effectively change the coupling coefficient of the connection between the primary side (12) and the secondary side (14) and the impedance of the primary side (12). To accommodate such changes in coupling constant and impedance, different compensation networks may be utilized on both the primary side (12) and the secondary side (14).

[0105] Compared with the parallel structure of four antennas shown in FIG. 4C, the stacked configuration of FIG. 4B is much more compact in the XY plane. In addition, this configuration is robust to angular misalignment because all antennas can be arranged center-aligned. Specifically, when the antennas are circular in shape, angular rotation has no effect on the coupling capacitance. However, compared with the parallel structure of four antennas shown in FIG. 4C, the mutual conductance of the stacked configuration of FIG. 4B may be reduced due to the increased mutual coupling capacitance.

[0106] FIG. 4C shows another embodiment of the configuration of antennas (80), (180), (280). Specifically, FIG. 4C shows a four parallel antenna (or four horizontal antenna) WPT system. The transmitter resonator (230) and receiver resonator (250) each include two antennas. One antenna of the transmitter resonator (230) and one antenna of the receiver resonator (250) together provide a forward path for power, and the other antenna of the transmitter resonator (230) and the other antenna of the receiver resonator (250) provide a reverse path for power.

[0107] For IPT, a magnetic field is generated by carrying a current through the transmitter antennas (232), (234) that can induce currents in the first receiver antenna (252) and the second receiver antenna (254). For CPT, an electric field (31B) is generated by creating a potential difference between the first antenna (232) and the second antenna (234) that can induce a potential across the first receiver antenna (252) and the second receiver antenna (254).

[0108] Compared to the transmitter resonator (130) and receiver resonator (150) shown in FIG. 4B, the transmitter resonator (230) and receiver resonator (250) having a horizontal configuration of the antenna may be desirable in applications where there are limitations on the Z-dimension of the resonators.

[0109] The transmitter resonator (230) comprises a first transmitter antenna (232) and a second transmitter antenna (234) separated in the X direction by a spacer (238). By separating the first transmitter antenna (232) and the second transmitter antenna (234) in the X direction, parasitic energy losses can be reduced. The first transmitter antenna (232) and the second transmitter antenna (234) can be substantially similar to the first transmitter antenna (132) and the second transmitter antenna (134), and the spacer (238) can be substantially similar to the spacer (138). Like the transmitter resonator (130), the first transmitter antenna (232) can have a larger XY plane area than the second transmitter antenna (234) to improve the forward path for transmitting power.

[0110] The spacer (238) may include any suitable material. For example, the spacer (238) may include air, a dielectric material, a ferrite, or a combination thereof. The spacer (238) may have a permittivity constant selected to alter the electric field (31A) and / or may have a permeability constant selected to alter the magnetic field (31B). The spacer (238) may include a high dielectric constant material that increases the capacitance of the transmitter resonator (230). The thickness and planar area of ​​the spacer (238) may depend on the thickness and / or planar area of ​​the first transmitter antenna (232) and the second transmitter antenna (234). In some embodiments, electrical isolation may be desired and a low dielectric constant material may be utilized for the spacer (238) (e.g., for shielding).

[0111] The receiver resonator (250) comprises a first receiver antenna (252) and a second receiver antenna (254) separated in the X direction by a spacer (258). By separating the first receiver antenna (252) and the second receiver antenna (254) in the X direction, parasitic energy losses can be reduced. The first receiver antenna (252) and the second receiver antenna (254) can be substantially similar to the first receiver antenna (152) and the second receiver antenna (154), and the spacer (258) can be substantially similar to the spacer (138). Like the receiver resonator (150), the first receiver antenna (252) can have a larger XY plane area than the second receiver antenna (254).

[0112] The spacer (258) may include any suitable spacer. The spacer (258) may include the same or similar material as the spacer (238) or a different material than the spacer (238). Compared to the spacer (258), the spacer (238) may have a smaller Z dimension to achieve a desired self-capacitance and / or self-inductance. This may effectively change the coupling coefficient of the connection between the primary side (12) and the secondary side (14) and the impedance of the primary side (12). To accommodate such changes in coupling constant and impedance, different compensation networks may be utilized on both the primary side (12) and the secondary side (14).

[0113] In some embodiments, the XY-planar area of ​​the spacer (258) may be different from the XY-planar area of ​​the spacer (238) to modify the self-inductance or self-capacitance of the transmitter resonator (230) or receiver resonator (250). For example, compared to the spacer (258), the spacer (238) may have a smaller XY-planar area as shown.

[0114] Figure 4D shows another embodiment of the configuration of antennas (80), (180), (280). Specifically, Figure 4D shows a six antenna WPT system that combines the stacked configuration of Figure 4B with the parallel configuration of Figure 4C. Each of the transmitter resonator (130) and receiver resonator (150) includes three antennas. One of the first transmitter antenna (332) and the second transmitter antenna (334) and one of the first receiver antenna (352) and the second receiver antenna (354) together provide a forward path for power, and the other of the first transmitter antenna (332) and the second transmitter antenna (334) and the other of the first receiver antenna (352) and the second receiver antenna (354) together provide a reverse path for power. The third transmitter antenna (336) and the third receiver antenna (356) function as auxiliary antennas that increase the equivalent self-capacitance and act as an electric field shield. In some embodiments, the third transmitter antenna (336) and the third receiver antenna (356) are passive (e.g., no potential difference is applied between the third transmitter antenna (336) and the third receiver antenna (356) and / or no current is carried through the third transmitter antenna (336) and the third receiver antenna (356)). For IPT, a magnetic field is generated that can induce a current in the first receiver antenna (352), (354), (356) by carrying a current through one or more of the transmitter antennas (332), (334), (336). For CPT, a voltage is applied to the first transmitter antenna (332), the second transmitter antenna (334), and / or the third transmitter antenna (336), creating a potential difference between the first transmitter antenna (332), the second transmitter antenna (334), and the third transmitter antenna (336), thereby creating an electric field (31B).

[0115] The transmitter resonator (330) comprises a first transmitter antenna (332) and a second transmitter antenna (334) separated in the X direction by a spacer (338), and a third transmitter antenna (336) separated from the first transmitter antenna and the second transmitter antenna and the spacer (338) by a second spacer (339). The third transmitter antenna (336) may provide an electric field shield to reduce undesired leakage of electric fields from the transmitter resonator (330). The third transmitter antenna (336) may include a ferrite sheet or surface to provide a magnetic field shield to reduce undesired leakage of magnetic fields from the transmitter resonator (330). Shielding or shaping of electric or magnetic fields may be possible by modifying the spacer (339).

[0116] The first transmitter antenna (332), the second transmitter antenna (334), and the third transmitter antenna (336) may be substantially similar to either the first transmitter antenna (132) or the second transmitter antenna (134). The spacers (338) and (339) may be substantially similar to the spacer (138). Like the transmitter oscillator (130), the first transmitter antenna (332) may have a larger XY plane area than the second transmitter antenna (334). The third transmitter antenna (336) may have a larger XY plane area than either the first transmitter antenna (334) or the second transmitter antenna (332).

[0117] The spacers (338), (339) may comprise any suitable material. For example, the spacers (338), (339) may comprise air, a dielectric material, a ferrite, or a combination thereof. The spacers (338), (339) may have a permittivity constant selected to alter the electric field (31A) and / or may have a permeability constant selected to alter the magnetic field (31B). The spacers (338), (339) may comprise a high permittivity material that increases the capacitance of the transmitter resonator (230). The thickness and planar area of ​​the spacers (338), (339) may depend on the thickness and / or planar area of ​​the first transmitter antenna (332), the second transmitter antenna (334), and the third transmitter antenna (336). In some embodiments, electrical isolation may be desired and low permittivity materials may be utilized for the spacers (338), (339) (e.g., for shielding).

[0118] The receiver resonator (350) includes a first receiver antenna (352) and a second receiver antenna (354) separated in the X direction by a spacer (358), and a third receiver antenna (356) separated from the first receiver antenna and the second receiver antenna and the spacer (358) by a second spacer (359). The third receiver antenna (356) may provide an electric field shield to reduce undesired leakage of electric fields from the receiver resonator (350). The third receiver antenna (356) may include a ferrite sheet or surface to provide a magnetic field shield to reduce undesired leakage of magnetic fields from the transmitter. Shielding or shaping of electric or magnetic fields may be possible by modifying the spacer (359). The first receiver antenna (352), the second transmitter antenna (354), and the third transmitter antenna (356) may be substantially similar to either the first receiver antenna (152) or the second transmitter antenna (154). The spacers (358), (359) may be substantially similar to the spacer (158). Like the receiver resonator (150), the first receiver antenna (352) may have a larger XY-plane area than the second receiver antenna (354). The third receiver antenna (356) may have a larger XY-plane area than either the first receiver antenna (354) or the second receiver antenna (352).

[0119] The spacers (358), (359) may include any suitable spacers. The spacers (358), (359) may include the same, similar, or different materials as the spacers (338), (339) or the spacers (338), (339). Compared to the spacers (358), (359), the spacers (338), (339) may have a smaller Z dimension to achieve a desired self-capacitance and / or self-inductance. This can effectively change the coupling coefficient of the connection between the primary side (12) and the secondary side (14) and the impedance of the primary side (12). To accommodate such changes in coupling constant and impedance, different compensation networks may be utilized on both the primary side (12) and the secondary side (14).

[0120] In some embodiments, the XY-plane area of ​​the spacer (358) may be different from the XY-plane area of ​​the spacer (338) to change the self-inductance or self-capacitance of the transmitter resonator (330) or the receiver resonator (350). For example, the spacer (338) may have a smaller dimension in the X-direction compared to the spacer (358). In some embodiments, the Z-direction dimension of the spacer (359) may be different from the Z-direction dimension of the spacer (339) to change the self-inductance or self-capacitance of the transmitter resonator (330) or the receiver resonator (350). For example, the spacer (339) may have a smaller dimension in the Z-direction compared to the spacer (359). This can effectively change the coupling coefficient of the connection between the primary side (12) and the secondary side (14) and the impedance of the primary side (12). To accommodate such coupling constant and impedance changes, different compensation networks may be utilized on both the primary side (12) and the secondary side (14).

[0121] In some embodiments, a magnetic shield may be provided around one or more of the transmitter resonator (30) and receiver resonator (50). For example, ferrite may be used as a magnetic shield and to reduce undesirable eddy currents in nearby metal objects. Ferrite (or other suitable material) may further be used to isolate the transmitter resonator (30) and / or receiver resonator (50) from surrounding metal objects, and thus the ferrite (or other suitable material) may function to increase the self-inductance of the antenna and / or mutual inductance of the resonators.

[0122] 6 shows a schematic diagram of a primary side (12) with a transmitter module (20) and a transmitter resonator (30) according to one embodiment of the present invention. The transmitter resonator (30) may include transmitter resonators (30), (130), (230), (330), or others described herein.

[0123] The transmitter module (20) includes a controller (22) that is configured to receive various inputs from sensors (24) (e.g., a load detector (24A), a transmitter power sensor (24B), an ambient object detector (24C), and / or a distance detector (24D)) and output control signals to various components (26) (e.g., an oscillator (26A), a power amplifier (26B), a filter network (26C), a matching network (26D), a compensation network (26E), and a V / I tuner (26F)).

[0124] The load detector (24A) is configured to detect the presence of a load (70) (shown in FIG. 7) connected to the secondary side (14). The load (70) may be, for example, a battery of an electric vehicle, such as an e-bike or an electric car, or any other suitable item requiring a power input. The load detector (24A) may be implemented with a physical sensor (for example, but not limited to, a light sensor, a pressure sensor, an infrared sensor, or a proximity sensor) and suitable software or firmware. For example, in some embodiments, power (e.g., current and voltage) is measured, for example, at point (24E) to determine the power consumed by the transmitter resonator (30) (e.g., measured by the transmitter power sensor (24B)). If the amount of power consumed by the transmitter resonator (30) increases above the baseline, the load detector (24A) may signal the controller (22) that a load (70) is present.

[0125] In other embodiments, the load detector 24A may be configured to measure the input impedance of the transmitter resonator 30 as experienced by the transmitter module 20 at the point 24E. For example, the presence of a resonant load proximate the transmitter resonator 30, including a secondary side 14 configured to drive a load 70, alters the input impedance of the transmitter resonator 30. This change in impedance, provided to the controller 22 by the load detector 24A, may be used by the transmitter controller 22 to determine whether a cooperative receiver is present proximate the transmitter resonator 30. The change in impedance induced in the transmitter resonator 30 by different receivers may be very clear and very distinctive, allowing the controller 22 to not only detect the presence or absence of a receiver proximate the transmitter resonator 30, but also to identify the type of receiver, such as, for example, but not limited to, different models of mobile phones or digital tablets.

[0126] The transmitter power sensor (24B) can measure power (e.g., measure current and voltage) at a point in time (24E) to determine how much power is being consumed by the transmitter resonator (30). Such information can be used, for example, by the load detector (24A) or to determine whether there is a desired efficient coupling between the transmitter resonator (30) and the receiver resonator (50).

[0127] The surrounding object detector (SOD) (24C) is configured to determine whether an object (e.g., a living object, such as a human or animal, or an inanimate object, such as a metal piece or otherwise) is in proximity to the transmitter resonator (30). The SOD (24C) may be implemented using a physical sensor (e.g., without limitation, a light sensor, a pressure sensor, an infrared sensor, a proximity sensor, a RADAR, or a LIDAR) or may be embodied as suitable software or firmware. For example, if the power consumed by the transmitter resonator (30) (as measured by the transmitter power sensor (24B)) drops during IPT, the SOD's software may determine that a metal piece (or any conductive object) is in proximity to the transmitter resonator (30) or the receiver resonator (50), and the SOD may provide a signal to the controller (22) indicating such presence. In some embodiments, if a metal object is detected in proximity to the transmitter resonator 30 or the receiver resonator 50, the controller 22 can increase the percentage of power delivered by the CPT to the transmitter module 20. If no organism is detected by the SOD 24C, the controller 22 can be configured to increase the power delivered to the transmitter resonator 30 (e.g., above the regulation level in the presence of an organism), or if an organism is detected in proximity by the SOD 24C, the controller 22 can be configured to decrease the power delivered to the transmitter resonator 30 below the regulation level.

[0128] The distance detector (24D) is configured to determine a distance between the transmitter resonator (30) and the receiver resonator (50). The distance detector (24D) may be implemented with a physical sensor (such as, but not limited to, an optical sensor, an ultrasonic sensor, an infrared sensor, a proximity sensor, a RADAR, or a LIDAR) or may be implemented by suitable software or firmware. For example, the distance detector (24D) may be configured to determine a distance between the transmitter resonator (30) and the receiver resonator (50) based on a change in transmit power measured by the transmitter power sensor (24B).

[0129] In one embodiment, one or more temperature sensors can monitor the temperature at the transmitter resonator 30 or the receiver resonator 50. If the temperature exceeds a predetermined limit, the controller 22 can cause the transmitter module 20 to reduce the rate of power delivered by the IPT, reduce the total power supplied to the transmitter resonator 30, or turn off power to the transmitter resonator 30 to prevent a fire hazard or thermal runaway.

[0130] The oscillator (26A) may be configured to control the frequency band, and / or bandwidth, and / or duty cycle (phase) (e.g., 5% to 50%) of the current being delivered to the transmitter resonator (30) in response to a signal from the controller (22).

[0131] The power amplifier 26B may be utilized to convert DC power to AC power. The power amplifier 26B may be utilized to adjust the power provided to the transmitter resonator 30 in response to a signal from the controller 22. Specifically, the controller 22 may send a signal to the power amplifier 26B to adjust the reflection coefficient of the power amplifier 26B. In some embodiments, the controller 22 may send a signal to the power amplifier 26B to turn off (sleep) when the load detector 24A does not detect a load, or to turn on when the load detector 24A detects a load.

[0132] The power amplifier (26B) includes a switching power amplifier (in single-ended mode or differential configuration) that can receive a square (sine) wave from the oscillator (26A) and generate a sine wave at a desired natural frequency to drive the transmitter resonator (30). FIG. 8 is a schematic diagram of an exemplary power amplifier (26B) that can be used in the transmitter (30). The power amplifier (26B) may be a differential class-F amplifier. The power amplifier (26B) has three inputs: two input signals (127A), (127B) that drive active elements (transistors) (127C), (127D) at a frequency set by the resonant frequency, and a DC voltage (127E) that is used to control the output power and operating region of the active elements.

[0133] The different load terminations are used to improve performance (e.g., output power, power conversion efficiency) and reduce unwanted harmonic levels. Specifically, a third high-frequency termination (127F) is placed in the series branch to shape the voltage waveform at the drain node (127G). A second harmonic termination (127H) is placed in the parallel branch to shape the voltage waveform at the drain node (127G). A first harmonic termination (127I) is placed in the series branch to shape the voltage waveform at the drain node (127G). The effect of the third harmonic termination can be considered in the second and first harmonic terminations (127H), (127I). The effect of the second harmonic termination can be considered in the first harmonic termination (127I). With respect to the differential configuration of the power amplifier (26B), an AC load (127J) (receiving the output power) is placed in series. The charging rate AC load (127J) may be a function of the transmitter resonator (30), the receiver resonator (50), and / or their alignment and position. The power amplifier (26B) may be configured to generate sufficient power to the transmitter resonator (30) such that an electric field, a magnetic field, or any combination of electric and magnetic fields may be generated by the transmitter resonator (30) and captured by the receiver resonator (50).

[0134] The filter network 26C can adjust the frequency response, such as the bandwidth, cutoff frequency, 3 dB frequency, and gain provided to the transmitter resonator 30, in response to a signal from the controller 22. The filter network can be configured to adjust the shape of the power waveform at the transmitter module 20 to increase the efficiency of the transmitter module 20.

[0135] The matching network (26D) may be configured to adjust the impedance to match the output of the power amplifier (26B) to the transmitter resonator (30).

[0136] The compensation network (26E) may be provided to drive the transmitter resonator (30) at a desired resonant frequency (e.g., the resonant frequency of the receiver resonator), thereby increasing mutual magnetic flux, reducing heat generation, and improving power transfer efficiency. The compensation network (26E) may include one or more capacitors to increase capacitance and one or more inductors to increase inductance. The compensation network (26E) may be configured to increase capacitance (and / or decrease inductance) and increase inductance (and / or decrease capacitance) as needed. When the transmission mode ratio is 100% CPT, the compensation network (26E) may function in a manner similar to any known CPT compensation network (e.g., the compensation network (26E) may function to increase inductance). Similarly, when the transmission mode ratio is 100% IPT, the compensation network (26E) may function in a manner similar to any known IPT compensation network (e.g., the compensation network (26E) may function to increase capacitance). However, when the transmission mode is part CPT and part IPT, less compensation may be required because the capacitance of the transmitter resonator (30) naturally compensates for the inductance of the transmitter resonator (30), and the inductance of the transmitter resonator (30) naturally compensates for the capacitance of the transmitter resonator (30). For example, at approximately 50% IPT and 50% CPT (e.g., a transmission mode ratio equal to 1), a compensation network may not be needed at all, or the use of a compensation network may be substantially limited, thereby increasing the efficiency of the WPT system (10).

[0137] As another example, between approximately 40-60% IPT and 40-60% CPT, a compensation network may not be needed at all or the use of a compensation network may be substantially limited, thereby increasing the efficiency of the WPT system (10). For this reason, the compensation network (26E) may include fewer or smaller inductors compared to CPT WPT systems and / or pure IPT WPT systems that require significant compensation. In some embodiments, if the capacitance of the transmitter resonator (30) is sufficiently low, additional compensation may be provided by the compensation network (26E). Similarly, if the inductance of the transmitter resonator (30) is sufficiently low, additional compensation may be provided by the compensation network (26E). The controller (22) may signal the compensation network (26E) how much and what type of compensation is needed based on, for example, the transmission mode ratio, the distance between the transmitter resonator (30) and the receiver resonator (50), the amount of power consumed by the transmitter resonator (30), the transmission efficiency, etc.

[0138] In some embodiments, the magnitude of compensation (e.g., capacitance increase or inductance increase) by compensation network (26E) is proportional to the absolute value of the difference between the transmission mode ratio and 1. For example, when the transmission mode ratio is greater than 1, compensation network (26E) may function to increase the inductance, and the amount of inductance increase may increase as the transmission mode ratio increases above 1. Similarly, when the transmission mode ratio is less than 1, compensation network (26E) may function to increase the capacitance, and the amount of capacitance increase may increase as the transmission mode ratio decreases below 1.

[0139] An embodiment of the V / I tuner (26F) is shown in more detail in FIG. 10. The input signal of the V / I tuner (26F) received from the matching network (26E) (in FIG. 6) is split by a splitter (262) to have two mutually asymmetric paths (261A) and (261B) for the input signal. The first phase shifter (264A) and the second phase shifter (264B) create a phase difference between the input voltage and the input current of the transmitter resonator (30) (in FIG. 6). The first phase shifter (264A) is controlled by the controller (22) (in FIG. 6) via the first phase splitter control line (263A), and the second phase shifter (264B) is controlled by the controller (22) (see FIG. 6) via the second phase splitter control line (263B). The first active switch (266A) and the second active switch (266B) receive signals from the first phase shifter (264A) and the second phase shifter (264B), respectively, and are controlled by the controller (22) via the first active switch control line (265A) and the second active switch control line (265B), respectively. The first active switch (266A) and the second active switch (266B) function to adjust the imaginary parts of the signals received from the first phase shifter (264A) and the second phase shifter (264B), respectively. The passive signal shaping networks (268A) and (268B) receive the adjusted signals from the first active switch (266A) and the second active switch (266B), respectively. The passive signal shaping networks (268A) and (268B) function to fine tune the signals received from the first active switch (266A) and the second active switch (266B), respectively, and in particular to reduce harmonics therein, before passing those signals to the combiner (269). The signals provided along the two mutually asymmetric paths (261A) and (261B) are combined by the combiner (269) and provided to the transmitter resonator (30).In other embodiments, the first phase shifter (264A) and the second phase shifter (264B) may be combined as one phase shifter that receives the input signal to the V / I tuner (26F), and the combined phase shifter may have two separate outputs that serve the active switches (266A) and (266B).

[0140] The V / I tuner (26F) adjusts the transmission mode ratio by adjusting the phase difference between the input current and the input voltage to the transmitter resonator (30) in response to a signal from the controller (22). The real part of the impedance seen by the transmitter module (20) can be adjusted by phase shifters (264A) and (264B), and its imaginary part can be adjusted by switches (266A) and (266B). For example, a 90 degree phase shift for every 3 of every 10 milliseconds can result in 30% magnetic power transmission and 70% power transmission.

[0141] The V / I tuner (26F) may be configured to adjust the current through and the potential applied to a respective transmitter antenna (e.g., the first and second transmitter antennas (32), (132), (232), (332), (134), (234), (334), or the third transmitter antenna (336)).

[0142] When current is passed through both the first transmitter antenna (132) and the second transmitter antenna (134), they each generate a magnetic field (31A) for IPT. If the current delivered to the second transmitter antenna (134) is reduced compared to the current delivered to the first transmitter antenna (132), a potential difference is created between the first transmitter antenna (132) and the second transmitter antenna (134), generating an electric field (31B) for CPT. To adjust between CPT and IPT, the current delivered to the second antenna (134) may be adjusted (e.g., passing less current through the second antenna (134) results in less IPT, and passing more current through the second antenna results in more CPT). For example, when it is desired to transfer power via an IPT, the I / V tuner (26F) may be configured to act as a short circuit connecting the first and second transmitter antennas together, thereby creating a series LC resonator that allows current to flow therein. Conversely, when it is desired to transfer power via a CPT, the I / V tuner (26F) may be configured to act as an open circuit that dumps current, thereby creating a potential difference between the first and second transmitter antennas. The I / V tuner (26F) may thereby be configured to control whether the first and second transmitter antennas (132) and (134) are effectively connected in series or in parallel.

[0143] Alternatively, when the first transmitter antenna (132) and the second transmitter antenna (134) are connected in parallel, the first transmitter antenna (132) and the second transmitter antenna (134) can be floated to generate an electric field (31B) for CPT in which the magnetic field (31A) is substantially not generated. To change the transmission mode ratio (e.g., to adjust between CPT and IPT), the I / V tuner (26F) may be configured (e.g., by a multiplexer in the I / V tuner (26F)) to alternate between (1) floating the first transmitter antenna (132) and the second transmitter antenna (134) to induce CPT, and (2) carrying current through the first transmitter antenna (132) and the second transmitter antenna (134) to induce IPT. The alternation may be performed in milliseconds or at a frequency between 10 Hz and 10 kHz. Allocating more time to floating the first transmitter antenna (132) and the second transmitter antenna (134) biases the transmission mode ratio more toward CPT, and allocating more time to carrying current through the first transmitter antenna (132) and the second transmitter antenna (134) biases the transmission mode more toward IPT.

[0144] In some embodiments, the elements (26) may be discrete elements in the transmitter module (20), while in other embodiments, one or more of the elements (26) may be part of an integrated circuit design.

[0145] FIG. 7 is a schematic diagram of a load (70) and the secondary side (14) (shown in FIG. 1) including the receiver resonator (50) and receiver module (40) according to one embodiment of the present invention.

[0146] The receiver resonator (50) may include any of the receiver resonators (50), (150), (250), (350), or others described herein. The receiver resonator (50) may be configured to capture power at a frequency set by the oscillating signal of the transmitter module (20), such as, but not limited to, between 1 MHz and 1 GHz.In some embodiments, the frequency set by the oscillation signal of the transmitter module (20) is between about 1 MHz and about 100 MHz, between about 1 MHz and about 200 MHz, between about 1 MHz and about 300 MHz, between about 1 MHz and about 400 MHz, between about 1 MHz and about 500 MHz, between about 1 MHz and about 600 MHz, between about 1 MHz and about 700 MHz, between about 1 MHz and about 800 MHz, between about 1 MHz and about 900 MHz, between about 1 MHz and about 1 GHz, between about 100 MHz and about 200 MHz, between about 100 MHz and about 300 MHz, between about 100 MHz and about 400MHz, approx. 100MHz to approx. 500MHz, approx. 100MHz to approx. 600MHz, approx. 100MHz to approx. 700MHz, approx. 100MHz to approx. 800MHz, approx. 100MHz to approx. 900MHz, approx. 100MHz to approx. 1GHz, approx. 200MHz to approx. 300MHz, approx. 200MHz to approx. 400MHz, approx. 200MHz to approx. 500MHz, approx. 200MHz to approx. 600MHz, approx. 200MHz to approx. 700MHz, approx. 200MHz to approx. 800MHz, approx. 200MHz to approx. 900MHz, approx. 200MHz to approx. 1GHz, approx. 300MHz to approx. 400MHz, approx. 300MHz to approx. 500MHz, approx. 300MHz to approx. 600MHz, approx. 300MHz to approx. 700MHz, approx. 300MHz to approx. 800MHz, approx. 300MHz to approx. 900MHz, approx. 300MHz to approx. 1GHz, approx. 400MHz to approx. 500MHz, approx. 400MHz to approx. 600MHz, approx. 400MHz to approx. 700MHz, approx. 400MHz to approx. 800MHz, approx. 400MHz to approx. 900MHz, approx. 400MHz to approx. 1GHz, approx. 500MHz to approx. 600MHz Hz, about 500 MHz to about 700 MHz, about 500 MHz to about 800 MHz, about 500 MHz to about 900 MHz, about 500 MHz to about 1 GHz, about 600 MHz to about 700 MHz, about 600 MHz to about 800 MHz, about 600 MHz to about 900 MHz, about 600 MHz to about 1 GHz, about 700 MHz to about 800 MHz, about 700 MHz to about 900 MHz, about 700 MHz to about 1 GHz, about 800 MHz to about 900 MHz, about 800 MHz to about 1 GHz, or about 900 MHz to about 1 GHz.In some embodiments, the frequency set by the oscillator signal of the transmitter module (20) is about 1 MHz, about 100 MHz, about 200 MHz, about 300 MHz, about 400 MHz, about 500 MHz, about 600 MHz, about 700 MHz, about 800 MHz, about 900 MHz, or about 1 GHz. In some embodiments, the frequency set by the oscillator signal of the transmitter module (20) is at least about 1 MHz, about 100 MHz, about 200 MHz, about 300 MHz, about 400 MHz, about 500 MHz, about 600 MHz, about 700 MHz, about 800 MHz, or about 900 MHz. In some embodiments, the frequency set by the oscillator signal of the transmitter module (20) is at most about 100 MHz, about 200 MHz, about 300 MHz, about 400 MHz, about 500 MHz, about 600 MHz, about 700 MHz, about 800 MHz, about 900 MHz, or about 1 GHz.

[0147] In some applications, frequencies in the Industrial, Scientific and Medical (ISM) frequency bands may be preferred. For the purposes of this disclosure, the ISM bands should be understood to be: 6.765 MHz to 6.795 MHz; 13.553 MHz to 13.567 MHz; 26.957 MHz to 27.283 MHz; 40.66 MHz to 40.70 MHz; 83.996 MHz to 84.004 MHz; 167.992 MHz to 168.008 MHz; 433.05 MHz to 434.79 MHz; and 886 MHz to 906 MHz. In other applications, frequencies in bands reserved for public use, such as, but not limited to, police communications or military bands, may be preferred. The receiver resonator (50) may be configured to harvest power from the magnetic field (31A) or electric field (31B) or any combination of these two fields at that frequency.

[0148] The receiver module 40 includes a controller 42 that is configured to receive various inputs from sensors 44 (e.g., a receiver power sensor 44A and a load detector 44B) and output control signals to various elements 46 (e.g., a compensation network 46A, a matching network 46B, a rectifier 46D, a filter 46C, and a load management 46E).

[0149] The receiver power sensor (44A) may measure the power (eg, measure the current and voltage) at time (44C) to determine how much power is being received by the receiver resonator (50).

[0150] Load detector (44B) is configured to detect the presence of load (70). Load detector (44B) may be implemented using a physical sensor (such as, but not limited to, a light sensor, a pressure sensor, an infrared sensor, or a proximity sensor) or as suitable software or firmware. For example, in some embodiments, current and voltage are measured by load detector (44B) to determine, for example, the power being received by load (50) at point (44D). If the amount of power being measured at point (44D) increases above a baseline, load detector (44B) may signal controller (42) that load (70) is present.

[0151] The compensation network 46A may be configured, in response to a signal from the controller 42, to maintain a desired resonant frequency of the receiver resonator 50, thereby improving the efficiency of power transfer from the transmitter resonator 30 to the receiver resonator 50. The compensation network 46A may function substantially like the compensation network 26E of the transmitter module 20.

[0152] The matching network (26D) may be configured to adjust the input impedance of the rectifier (46D) to match the desired impedance of the resonator (30) to achieve maximum power transfer.

[0153] The rectifier (46D) may be configured to convert the AC power received by the receiver antenna (50) to DC power for providing to the load (70).

[0154] The filter (46C) may be configured to shape the waveform of the power output from the rectifier (46D) according to a signal from the controller (42) to improve the overall power efficiency of the receiver module (40).

[0155] The load management (46E) may be configured to provide a suitable voltage and current to the load (70) and / or extract maximum power from the rectifier (46D) by adjusting its input impedance (e.g., the output impedance of the rectifier (46D)).

[0156] In some embodiments, the management (46E) or other components may be configured to communicate (wirelessly or wired) with an external device (e.g., the load (70)) to provide appropriate information for data analysis. Such information may include, for example, without limitation, the presence of the load (70), the charge level of the load (70), the charge rate of the load (70), the state of the load (70), the current voltage, capacity, and / or the time remaining to charge the load (70). The load management (46E) may utilize such information (or communicate such information to the controller (42) or controller (22)) to, for example, adjust the transmission mode ratio to achieve optimal energy transfer between the primary side (12) and the secondary side (14). The load management (46E) may provide such information to a user via a display. Such a display may be built into one or more of the primary side (12) and secondary side (14) or may be accessible via software on a mobile device, such as, for example, an application on a cell phone or tablet in wireless (or wired) communication with the load management (46E) or controller (22) or controller (42).

[0157] In some embodiments, the components (46) are discrete elements within the receiver module (40), while in other embodiments, one or more of the components (46) are part of an integrated circuit design.

[0158] In some embodiments, the primary side (12) may include multiple transmitter resonators (30) and / or the secondary side (14) may include multiple receiver resonators (50). In such embodiments, each of the transmitter resonators (30) and / or receiver resonators (50) may be controlled in a similar manner. In other embodiments, each of the transmitter resonators (30) and / or receiver resonators (50) may be individually controlled. For example, in some embodiments, the primary side (12) may rely more on a transmitter resonator (30) that is experiencing less interference (e.g., due to nearby metal objects), that is not nearby living beings, or that is transmitting power more efficiently, and / or similarly, the secondary side (14) may rely more on a receiver resonator (50) that is experiencing less interference (e.g., due to nearby metal objects), that is not nearby living beings, or that is receiving power more efficiently. Such control may be provided or facilitated, for example, by the transmitter module (20) and the receiver module (40) and / or communications therebetween.

[0159] In some embodiments, the primary side (12) may communicate with the secondary side (14) (e.g., the controller (22) may communicate with the controller (42)) to share, for example, the presence of the load (70), the charge level of the load (70), the power transfer efficiency, the charge rate of the load (70), the state of the load (70), the current voltage, capacity, the time remaining to charge the load (70), and the like. In some embodiments, such information may be transmitted at a frequency different from the frequency of the power transfer between the primary side (12) and the secondary side (14). In some embodiments, the frequency of the power transfer between the primary side (12) and the secondary side (14) may be adjusted (e.g., the amplitude may be adjusted) to enable communication between the primary side (12) and the secondary side (14). For example, the primary side (12) and the secondary side (14) may communicate via Bluetooth (e.g., 2.4 GHz) or a signal frequency similar to that of GPS (e.g., 10 GHz). In some embodiments, there may be additional units that can separately collect data and transmit the data back and forth between the primary side (12) and / or secondary side (14). For example, Wifi may be utilized to upload data from the primary side (12) and / or secondary side (14) to an online portal (e.g., a website or mobile application associated with the primary side (12) and / or secondary side (14)).

[0160] In some embodiments, it may be desirable to transfer power between two receivers (40) (e.g., peer-to-peer power transfer). For example, when a first e-bike with a first receiver has a dead or low battery and a second e-bike with a second receiver and a charged battery (at least a partially charged battery) is nearby, it may be desirable to transfer power from the second e-bike to the first e-bike (e.g., when no transmitter is nearby). To enable such a transfer of power between receivers, a phase shifter is integrated into the rectifier (46D), thereby enabling the receiver to also function as a transmitter.

[0161] 9 is a schematic diagram of a rectifier (46D) with an integrated phase shifter. In some embodiments, the rectifier (46D) includes a separate phase shifter.

[0162] The rectifier (46D) may be a switching self-synchronous rectifier (in a single-ended mode or differential configuration) that may be configured to receive a sinusoidal wave (e.g., AC power) from the receiver resonator (50) at a particular resonant frequency. The rectifier (46D) may be a differential class-F self-synchronous rectifier. The rectifier (46D) may capture sufficient power from the receiver resonator (50) such that an electric field, a magnetic field, or any combination of electric and magnetic fields may be captured by the receiver resonator (50).

[0163] The rectifier (46D) has an input (147A) (e.g., AC power) that drives an active element (147B) (e.g., a transistor) at a frequency set to the resonant frequency, and has an output (147D) (e.g., DC voltage) across a DC load (used to control the output power, input impedance, and operating region of the active element). In this design, different load terminations are used to improve performance (e.g., output power and power conversion efficiency). A third harmonic termination (147D) is placed in the series branch to shape the voltage waveform at the drain node (147E). A second harmonic termination (147F) is placed in the parallel branch to shape the voltage waveform at the drain node (147E). A first harmonic termination (147G) is placed in the series branch to shape the voltage waveform at the drain node (147E). The effect of the third harmonic termination may be considered in the second and first harmonic terminations. The effect of the second harmonic termination may be considered in the first harmonic termination.

[0164] In a differential configuration, the AC source (147A) is placed in series. The AC source (147A) may be a function of the power received by the receiver resonator (50) and the alignment and position of the receiver resonator (50) relative to the transmitter resonator (30). The DC load (147C) may be a single-ended load.

[0165] The rectifier (46D) may include two phase shifters (147H) in a differential configuration (but only one phase shifter in a single-ended configuration). The phase shifter (147H) adjusts the appropriate phase difference between the AC power supply and the gate signal of the transistor (147B). The phase difference between the gate signal and the AC power supply (147A) can change the performance of the self-synchronous rectifier (e.g., the power conversion efficiency and the operating region of the transistor). The difference can also change the input impedance of the self-synchronous rectifier (46D) and / or the optimum DC load (147C) of the rectifier (46D).

[0166] The rectifier (46D) may comprise two level shifters (147I) in a differential configuration (but only one level shifter in a single-ended configuration). The level shifter (147I) can adjust the appropriate amplitude for the gate signal of the transistor (147B). The amplitude level of the gate signal can change the performance of the self-synchronous rectifier (e.g., the power conversion efficiency and the operating region of the transistor).

[0167] The WPT system (10) (transmitters and / or receivers described herein) can be integrated into a variety of applications, including, but not limited to, electric vehicles, electric boats, electric planes, electric trucks, e-bikes, electric scooters, electric skateboards, etc. One exemplary, non-limiting application is a bike share fleet, where various docking stations are provided that integrate one or more transmitters (e.g., primary side (12)) and e-bikes equipped with receivers (e.g., secondary side (14)) and batteries (loads (70)) can be charged at the docking stations.

[0168] In some applications, the primary (12) or secondary (14) may be configured to transmit power using other systems not described herein, and the transmission mode ratio may be adjusted from CPT to IPT to provide compatibility with other CPT and / or IPT systems, even if they are not specifically designed to work with the power transmission systems described herein.

[0169] While a number of exemplary aspects and embodiments have been described above, those of skill in the art will recognize certain modifications, permutations, additions, and subcombinations thereof. Accordingly, it is intended that the following appended claims and the claims introduced below be interpreted to include all such modifications, permutations, additions, and subcombinations consistent with the broadest interpretation of the entire specification.

[0170] In a first aspect, each of the systems described above and shown in FIGS. 1-10 form a dual mode near-field resonant wireless power transfer system (10) configured for simultaneous capacitive and inductive power transfer according to an adjustable transmission mode ratio at a variable resonant power signal oscillation frequency, the system (10) comprising a transmitter subsystem (12) including a transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336) and a power signal tuner module (26F) configured to tune the transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336) and a power signal tuner module (26F) for ... a transmitter subsystem (12) configured to adjust a transmission mode ratio by adjusting the power signal provided to the transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336); and a receive subsystem (14) including a receiver antenna subsystem (52), (152), (252), (352), (154), (254), (354), (356) configured to receive power from the transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336) at the transmission mode ratio.

[0171] The tuner module (26F) may be configured to adjust the power signal by adjusting a phase difference between a current and a voltage of the power signal provided to the transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336). The transmitter subsystem (12) may further comprise a controller (22) and at least one sensor (24), where the controller (22) is configured to receive sensor information from the at least one sensor (24) and automatically provide tuning instructions to the tuner module (26F) based on the sensor information, and where the tuner module (26F) is configured to adjust a phase difference between a voltage and a current of the power signal provided to the transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336) in accordance with the tuning instructions.

[0172] The system (10) resonates at a resonant frequency that is freely variable within a predetermined band based on the degree of coupling between the transmitter subsystem (12) and the receiver subsystem (14). The predetermined band may be, for example, without limitation, a publicly designated or reserved Industrial, Scientific and Medical (ISM) band or a specific user-dedicated band. The Q factor of the system (10) may be reduced to an extent that allows the power signal oscillation frequency to vary within the conflict limits of the predetermined frequency band. With the Q factor reduced, the system (10) may utilize any of a number of different resonant frequencies within the predetermined frequency band during the process of power transmission. The coupling between the transmitter subsystem (12) and the receiver subsystem (14), and the associated absorption of power by the resonating receiver subsystem (14), ensures that little electromagnetic radiation is radiated into the far-field region when the system (10) is in operation. The configuration as described herein with reference to FIGS. 1-10, together with the preceding frequency aspects, make the system (10) a two-way near-field resonant wireless power transmission system. It should be noted that in the wireless power transfer system (10), power is transferred from the primary subsystem to the secondary subsystem via capacitive and / or electromagnetic coupling, but is not transferred to any substantial extent via electromagnetic radiation.

[0173] In a further aspect described with reference to the drawings above and the flow chart of FIG. 11, there is provided a near field wireless communication method

[1000] for bimodally transmitting power according to an adjustable transmission mode ratio at a variable resonant power signal oscillation frequency, the method comprising the steps of: providing a transmitter subsystem (12) comprising a power signal tuner module (26F) and a transmitter antenna subsystem (32), (132), (232), (332), (134), (234), (334), (336) configured to resonate at the resonant power signal oscillation frequency

[1010] ; providing a receiver subsystem (14) comprising a receiver antenna subsystem (52), (152), (252), (352), (154), (254), (354), (356) configured to resonate at the resonant power signal oscillation frequency

[1012] ; providing a power signal from the tuner module (26F) to the transmitter antenna subsystems (32), (132), (232), (332), (134), (234), (334), (336) at the power signal oscillation resonant frequency; and providing a power signal from the tuner module (26F) to the transmitter antenna subsystems (32), (132), (232), (332), (134), (234). and receiving the transmitted power at the receiver subsystem (14) at the power signal oscillation resonant frequency via the receiver antenna subsystems (52), (152), (252), (352), (154), (254), (354), (356) at the transmission mode ratio. Adjusting the transmission mode ratio may include adjusting a phase difference between a current and a voltage of the power signals provided to the transmitter antenna subsystems (32), (132), (232), (332), (134), (234), (334), (336).

[0174] The step of providing a transmitter subsystem (12)

[1010] may further include providing a controller (22) and at least one sensor (24), and adjusting the phase difference between the current and the voltage may be performed by the tuner module (26F) via instructions from the controller (22) based on sensor information received by the controller (22) from the at least one sensor (24). The instructions from the controller (22) may be automatically issued to the tuner module (26F) upon receiving the sensor information by the controller (22). The tuner module (26F) may automatically execute the instructions from the controller (22) to change the phase difference.

[0175] The method may further include varying the resonant power signal oscillation frequency within a predetermined frequency band. The predetermined frequency band may be an Industrial, Scientific and Medical (ISM) frequency band. Providing the transmitter subsystem may include providing a transmitter subsystem that is detuned such that the resonant power signal oscillation frequency can vary within conflict limits within the predetermined frequency band.

[0176] In further embodiments described with reference to Figures 12, 13A, and 13B and Figures 1-10, a multi-transmitter dual-mode near-field resonant wireless power transfer system (10') is configured for simultaneous capacitive and inductive power transfer according to an adjustable transmission mode ratio at a variable resonant power signal oscillation frequency. The system (10') comprises a multi-transmitter subsystem (12') including a plurality of transmitter resonators (30A')-(30I'), each driven by a corresponding dedicated transmitter module (20A')-(20I'), where each transmitter resonator and corresponding transmitter module (e.g., (30E') and (20E'), respectively) are in accordance with the description above and with reference to Figures 1-10. Figure 12 is a schematic diagram of an embodiment of the system (10'), where the transmitter resonators (30A')-(30I') are shown in a row as nine resonators, but their formal spatial locations are not shown. An embodiment of a spatial layout of the multiple transmitter subsystem (12') is shown in Figures 13A and 13B and described below. In the system (10'), the resonant receiver subsystem (14) may be the same as or substantially similar to the resonant receiver system described above and referenced by Figures 1-10. In the embodiment shown in Figure 12, the resonant receiver subsystem (14) may be implemented in, for example, but not limited to, a mobile phone or a digital "tablet". The resonant receiver subsystem (14) is represented by dashed lines for clarity in Figure 13A. In one embodiment, each operating transmitter resonator (30A')-(30I') and each corresponding transmitter module (20A')-(20I') may function in the same or substantially similar manner as the transmitter resonator (30) and transmitter module (20) described above and shown in Figures 1-10. An embodiment of a spatial layout of the multiple transmitter subsystem (12') is represented in Figures 13A and 13B. FIG. 13B is a diagram of a multiple transmitter subsystem (12') in an inverted orientation relative to the orientation of FIG. 13A.

[0177] In the exemplary embodiment of the system 10' shown in Figures 12, 13A, and 13B, the multiplexed transmitter subsystem 12' comprises nine pairs of transmitter resonators 30A'-30I' arranged in a square array and corresponding transmitter modules 20A'-20I'. The transmitter modules 20A'-20I' are obscured by the grounded base plate 35' in Figure 13A, but are visible in Figure 13B. In more general embodiments, other numbers of pairs of resonators and transmitter modules may be utilized, and the resonator array need not be square or rectangular. By way of example and without limitation, the resonator array may have a hexagonal configuration. In some embodiments, the array is preferably close packed, within the constraint of having a grounded shielding grid separating and bounding the transmitter resonators 30A'-30I'. The grounded shielding grid (33') defines an array of transmitter resonators (30A')-(30I') in the lateral direction. The grounded shielding grid (33') is disposed at a constant distance (37') from the periphery of each of the transmitter resonators (30A')-(30I') to ensure a consistent electric field behavior and associated capacitance between the transmitter resonators (30A')-(30I') and the grounded shielding grid (33'). The term "shielding distance" is used herein to describe this distance between the resonators (30A')-(30I') and the grounded shielding grid (33').

[0178] In one embodiment, the grounded shielding grid 33' ensures that the electric fields of the transmitter resonators 30A'-30I' are completely spatially separated and therefore spatially independent. The transmitter resonators 30A'-30I' may have magnetic fields selected to be separated from one another by spatial orientation. In another embodiment, the grounded shielding grid 33' may be formed of or coated with a highly conductive ferrite material to separate the magnetic fields generated by the transmitter resonators 30A'-30I'.

[0179] As shown in FIGS. 13A and 13B, the transmitter resonators 30A'-30I' and their corresponding transmitter modules 20A'-20I' are mounted substantially congruent with one another on opposite sides of the grounded base plate 35', with each transmitter resonator (e.g., 30E') adjacent to its corresponding transmitter module 20E'. In other embodiments, there may not be a fixed spatial relationship between the transmitter resonators and their corresponding transmitter modules. The array of transmitter resonators 30A'-30I' share a common transmission plane defined by the collective top surfaces of the transmitter resonators 30A'-30I' in FIG. 13A. For aesthetics and protection, the array of transmitter resonators 30A'-30I' may be covered with a dielectric plate (not shown in FIG. 13A). A dielectric plate separates the receiver subsystem (14) and the transmitter resonators (30A')-(30I').

[0180] In Figures 12 and 13A, an embodiment of a resonant receiver subsystem (14) is shown generally as an overlapping subset of multiple transmitter resonators (30A')-(30I'). In accordance with Figures 12 and 13A, the overlapping transmitter resonators are shown as (30D'), (30E'), (30G'), and (30H'). In Figure 13A, the resonant receiver subsystem (14) is shown as dashed rectangles over the mutually adjacent transmitter resonators (30D'), (30E'), (30G'), and (30H'). The controller of any of the transmitter modules (20A')-(20I') can determine the presence or absence of a resonating receiver subsystem (14) adjacent to or overlapping its corresponding transmitter resonator (30A')-(30I'), and based on these detections, the controller can turn on or off the power signal to its corresponding transmitter resonator (30A')-(30I').

[0181] If the power amplifiers of the transmitter modules (20A')-(20I') provide power signals to the transmitter resonators (30A')-(30I'), causing the transmitter resonators (30I')-(30A') to transmit power, and the controllers of the transmitter modules (20A'), (20B'), (20C'), (20F'), and (20I') determine that there are no resonant receivers within their frequency range proximate to the transmitter resonators (30A'), (30B'), (30C'), (30F'), and (30I'), then the controllers can turn off the power signals to the transmitter resonators (30A'), (30B'), (30C'), (30F'), and (30I').

[0182] If the power amplifiers of the transmitter modules (20A')-(20I') do not provide power signals to the transmitter resonators (30A')-(30I') and the controllers of the transmitter resonators (30D'), (30E'), (30G'), and (30H') determine that there are resonant receiver subsystems (14) that overlap or are adjacent to the resonators (30D'), (30E'), (30G'), and (30H'), the controllers turn on the transmittable power provided by the transmitter modules (20D'), (20E'), (20G'), and (20H') to the transmitter resonators (30D'), (30E'), (30G'), and (30H'). This configuration ensures that only the transmitter resonators that are adjacent to the resonant receiver subsystem (14) consume and transmit power to the resonant receiver subsystem (14).

[0183] The input impedance of a particular transmitter resonator 30A'-30I' may be used to detect the presence or absence of a resonating receiver subsystem 14 in close proximity to the particular transmitter resonator. The absence or presence of a resonating receiver subsystem 14 in close proximity to the particular transmitter resonator causes the input impedance of the transmitter resonator to vary. As explained above with reference to FIG. 6, the effect of a particular resonating receiver subsystem 14 is not only distinct so that the presence or absence of a receiver can be detected, but also characteristic so that the type of receiver can be identified by its effect on the input impedance of the transmitter resonator. The size of the receiver resonator, among other things, has a profound effect on the input impedance of the particular transmitter resonator 30A'-30I'.

[0184] In one embodiment of the system 10', the transmitter module 20E' shown in Figures 12 and 13B is the transmitter module associated with one of the four transmitter resonators 30D', 30E', ​​30G', and 30H' that are duplicated by the resonant receiver subsystem 14. Detailed structures of each of the transmitter modules 20A'-20I' are provided in Figures 6 and 8. The process begins with the power amplifiers 26B of the transmitter modules 20A'-20I' providing no power signal to the corresponding transmitter resonators 30A'-30I'.

[0185] Turning now to the transmitter module (20E'), its load detector (24A) is configured in this embodiment to measure the input impedance of the transmitter resonator (30E'). The load detector (24A) provides the input impedance measurement to the controller (22). The default input impedance measurement is stored in a register of the controller (22) and represents the input impedance of the transmitter resonator (30E') in the absence of a resonating receiver subsystem proximate to the transmitter resonator (30E'). The placement of the resonating receiver subsystem (14) proximate to the transmitter resonator (30E'), as shown in FIG. 12, causes a new and different input impedance measurement by the load detector (24A) which is provided to the controller (22) by the load detector (24A). The controller (22) compares the new input impedance measurement, referred to herein as the "first input transmitter resonator impedance change" or "primary transmitter resonator input impedance change", to the default impedance measurement stored in the register. Based on this first input impedance change, the controller 22 determines whether a receiver resonator, such as a resonator of the resonant receiver subsystem 14, is present proximate to the transmitter resonator 30E'. To determine the absence or presence of a receiver resonator proximate to the transmitter resonator 30E', ​​the controller 22 may be preprogrammed with a minimum input impedance change that must be exceeded before a receiver resonator is considered to be present by the controller 22.

[0186] If the controller 22 determines that a receiver resonator, e.g., a resonator of the resonant receiver subsystem 14, is present in close proximity to the transmitter resonator 30E', ​​the controller 22 commands the power amplifier to assume an "ON" state, whereby power is provided to the transmitter resonator 30E', ​​which in turn is transmitted to the resonant receiver subsystem 14. If the controller 22 determines that a receiver resonator, e.g., a resonator of the resonant receiver subsystem 14, is not present in close proximity to the transmitter resonator 30E', ​​the controller 22 commands the power amplifier to assume an "OFF" state, whereby power is not provided to the transmitter resonator 30E', ​​and power is not transmitted to the resonant receiver subsystem 14. The same process is performed by all transmitter modules 20A'-20I' independently for their corresponding transmitter resonators 30A'-30I'. As a result, the power amplifiers of transmitter modules (30D'), (30E'), (30G'), and (30H') that are duplicated by the resonant receiver subsystem (14) are turned on, and the power amplifiers of transmitter modules (30A'), (30B'), (30C'), (30F'), and (30I') that are not duplicated by the resonant receiver subsystem (14) are turned off.

[0187] It should be noted that receiver resonators of different sizes present dramatically different impedances at point 24A to the load detector 24A of the transmitter modulator 20. The difference in impedance measured when a given receiver resonator partially overlaps a particular transmitter resonator compared to when it completely overlaps that transmitter resonator is not as dramatically different as the difference in impedance due to receiver resonator size. This allows the controller 22 of any transmitter module 20A'-20I' to distinguish between small and large receiver resonators in close proximity to a corresponding transmitter resonator 30A'-30I'.

[0188] According to an embodiment, the power signal frequency and phase settings between those transmitter resonators (e.g., (30D'), (30E'), (30G'), and (30H')) duplicated by a resonant receiver subsystem, e.g., resonant receiver subsystem (14), are described herein. In order to maximally efficiently transfer power from the combination of transmitter resonators (30D'), (30E'), (30G'), and (30H') that are receiving power, the power signals of resonators (30D'), (30E'), (30G'), and (30H') should have the same frequency and should also be in phase with each other. Assuming that the frequencies of the power signals of the transmitter resonators (30D'), (30E'), (30G') and (30H') described above and with reference to Figures 1 to 10 are different within a tolerance band, a prerequisite in this embodiment of Figures 12, 13A and 13B is that the frequencies of the power signals of the transmitter resonators (30D'), (30E'), (30G') and (30H') are adjusted to be identical, and then their phases are locked together so that the power signals from the transmitter resonators (30D'), (30E'), (30G') and (30H') are perfectly synchronized or in phase.

[0189] In one embodiment, to ensure that the controllers (22) of the overlapping transmitter resonators (30D'), (30E'), (30G'), and (30H') all set their corresponding oscillators (26A) to the same frequency, the controllers (22) of the transmitter modules (20A')-(20I') are all provided with an identical table of selected frequencies within a given tolerance band, e.g., an ISM band. Within that particular ISM band, several individual frequencies are selected and included in the frequency table. Thus, the number of tabled frequencies within that ISM band is finite and limited, and the tabled frequencies are spaced widely enough so that the various controllers (22) of the transmitter modules (20D'), (20E'), (20G'), and (20H') can determine the frequency of the power signal from the first impedance difference described above. Despite small variations in their impedances, the controllers (22) of transmitter modules (20D'), (20E'), (20G'), and (20H') all select the same individual frequencies within the band of allowed frequencies for the power signals of their respective oscillators (26A) and power amplifiers (26B).

[0190] In one embodiment, to ensure that all resonators (30D'), (30E'), (30G'), and (30H') have not only the same power signal frequency but also the same phase, the following procedure is adopted and programmed into the software of each of the controllers (22) of the transmitter modules (20A')-(20I'): Statistically, the first independent controller (22) of the controllers of the transmitter modules (20D'), (20E'), (20G'), and (20H') first turns on its corresponding oscillator (26A) and power amplifier (26B) to provide power through its transmitter resonator of the resonant receiver subsystem (14). A second one of the controllers of the transmitter modules (20D'), (20E'), (20G') and (20H') measures the input impedance of its corresponding transmitter resonator and detects a small second change in that impedance due to the function of the first transmitter resonator by its corresponding load detector (24A). In effect, the second controller (22) sees a reflection of the impedance of the first transmitter resonator through the interaction of the resonant receiver subsystem (14) with the first transmitter resonator. The second controller (22) is programmed to conclude, based on the second impedance change, that the other controller should first turn on its oscillator (26A) and power amplifier (26B). Having concluded this, the second controller (22) then turns on its oscillator (26A) and power amplifier (26B) and varies the phase of the power signal while using its transmitter power sensor (24B) to measure the power transmitted by its corresponding transmitter resonator. The second controller (22) then varies the phase of its oscillator to find the phase at which maximum power transfer occurs and sets the oscillator phase to that value. The oscillator phase determined in this manner ensures that the phase of the power signal transmitted by the second transmitter resonator is equal to the phase of the power signal transmitted by the first transmitter resonator to the resonant receiver subsystem (14). In one embodiment, the setting of the oscillator phase is based on substantially maximizing the power transfer, rather than making the phases of the power signals perfectly equal.

[0191] In another embodiment, further based on the fact that the transmitter resonators (30D'), (30E'), (30G'), and (30H') are overlapped by the resonant receiver subsystem (14), the detection of the proximity of the resonant receiver subsystem (14) is based on the test signal power consumed by the transmitter resonators (30D'), (30E'), (30G'), and (30H'). In this embodiment, a low amplitude power signal is first maintained by the oscillators and power amplifiers corresponding to all of the transmitter resonators (30A')-(30I'). Then, the controllers (22) of all the transmitter modules (20A')-(20I') sense the power consumed by their corresponding transmitter resonators (30) using their corresponding transmitter power sensors (24B). Using their corresponding transmitter power sensors (24B), the controllers (22) of the transmitter modules (20D'), (20E'), (20G'), and (20H') sense that power is being consumed through their corresponding transmitter resonators (30D'), (30E'), (30G'), and (30H'). Based on the detection of the consumed test signal power, the controllers (22) of the transmitter modules (20D'), (20E'), (20G'), and (20H') turn on full power of their corresponding power amplifiers (26B). The term "consumption of first test signal power" is used herein to describe this power consumed from the test signal through the transmitter resonators (30D'), (30E'), (30G'), and (30H'). The test power signals of the power amplifiers 26B of the transmitter modules 30A', 30B', 30C', 30F', and 30I' that are not overlapped by the resonant receiver subsystem 14 may be turned off after a suitable test period.

[0192] Similar to the impedance-based embodiments described above, the controllers (22) of the transmitter modules (20D'), (20E'), (20G'), and (20H') may require a threshold power consumption in order to consider the resonant receiver subsystems (14) to be in close proximity to their corresponding transmitter resonators (30D'), (30E'), (30G'), and (30H').

[0193] In one embodiment, to ensure that the controllers (22) of the overlapping transmitter resonators (30D'), (30E'), (30G'), and (30H') all set their corresponding oscillators (26A) to the same frequency, the controllers (22) of the transmitter modules (20A')-(20I') are all provided with an identical table of selected frequencies within a predefined tolerance band, e.g., an ISM band. Within that particular ISM band, a number of individual frequencies are selected and included in the frequency table. Thus, the number of tabled frequencies within that ISM band is finite and limited, and the tabled frequencies are spaced wide enough so that the various controllers (22) of the transmitter modules (20D'), (20E'), (20G'), and (20H') can determine the power signal frequency from the first test signal power consumption described above. Despite small variations in their power consumption values, the controllers 22 of transmitter modules 20D', 20E', 20G', and 20H' all select the same individual frequencies within the allowed bands for the power signals of their respective oscillators 26A and power amplifiers 26B.

[0194] In one embodiment, to ensure that all of the resonators (30D'), (30E'), (30G'), and (30H') have not only the same power signal frequency but also the same phase, the following procedure is adopted and programmed into the software of each of the controllers (22) of the transmitter modules (20A')-(20I'): Statistically, the first independent controller (22) of the controllers of the transmitter modules (20D'), (20E'), (20G'), and (20H') first turns on its corresponding oscillator (26A) and power amplifier (26B) to provide power to the resonant receiver subsystem (14) through its transmitter resonator. A second one of the controllers of the transmitter modules (20D'), (20E'), (20G') and (20H') measures the power consumption of its corresponding transmitter resonator and detects a small second change in its power consumption due to the functioning of the first transmitter resonator by its corresponding transmitter power sensor (24B). In effect, the second controller (22) sees a reflection of the impedance of the first transmitter resonator through the interaction of the resonant receiver subsystem (14) with the first transmitter resonator. The second controller (22) is programmed to conclude, based on the second change in power consumption, that the other controller first turned on its oscillator (26A) and power amplifier (26B). Having concluded this, the second controller (22) then turns on its oscillator (26A) and power amplifier (26B) and varies the phase of the power signal while measuring the power transmitted by its corresponding transmitter resonator using its transmitter power sensor (24B). The second controller (22) then looks for the phase at which maximum power transmission occurs and sets the oscillator to that phase. Setting the oscillator phase in this manner ensures that the phase of the power signal transmitted by the second transmitter resonator to the resonant receiver subsystem (14) is equivalent to the phase of the power signal transmitted by the first transmitter resonator to the resonant receiver subsystem (14).In an embodiment, the setting of the oscillator phase is based on substantially maximizing power transfer, rather than perfectly equalizing the phase of the power signals.

[0195] In one embodiment, two different resonant receiver subsystems are adjacent to the multiple transmitter subsystem (12') and different ones or combinations of the transmitter resonators (30A')-(30I'). When overlapping with a resonant receiver subsystem, there is no a priori reason why two different transmitter resonators, or two different groups of transmitter resonators overlapped by two resonant receiver systems, should operate at the same frequency or phase, nor is there a requirement that they do so. The grounded shielding grid (33') ensures this multi-way independence by isolating all of the individual transmitter resonators (30A'-30I') from each other. However, transmitter resonators that are overlapped by one particular resonant receiver subsystem must actively synchronize their corresponding power signal amplifiers by their controllers, as described above. This can result in two different transmitter resonators, or two different groups of resonators, operating at two specific different locked-in frequencies in the band, with all signals of a particular group being in phase with each other.

[0196] In the above, it is described how two transmitter resonators transmitting power to the same receiver resonator are programmed to behave in order to ensure that the two transmitter resonators have the same power signal, thereby ensuring maximum power transfer. A different situation occurs when two adjacent transmitter resonators, for example (30A') and (30B') in FIG. 14, are transmitting to two substantially similar corresponding receiver subsystems (14A) and (14B). Both transmitter resonators (30A') and (30B') have fringing fields, whose field lines extend, for example, from the transmitter resonator (30A') to the receiver subsystem (14B') and from the transmitter resonator (30B') to the receiver subsystem (14A). Generally, there is no particular physical structure in the system 10' that prevents, for example, the electric field of the transmitter resonator 30A' from interacting with the receiver resonator of the receiver subsystem 14B.

[0197] In one embodiment, when transmitter resonators (30A') and (30B') both serve the same large receiver resonator that overlaps with both transmitter resonators (30A') and (30B') (as in FIG. 13A), fringe fields are essentially not a problem since both transmitter resonators (30A') and (30B') carry power signals of the same phase and frequency. In the case of the situation shown in FIG. 14, the requirement is to ensure that power is not parasitized from the transmitter resonator (30A') by the fringe fields of a given transmitter resonator (e.g. (30A')) interacting with a receiver subsystem (e.g. (14B) that is intended to accept power from a neighboring transmitter resonator (30B')). One way to achieve this goal is to drive the two adjacent transmitter resonators (30A') and (30B') 180 degrees out of phase with each other, so that the overlapping fringe fields from the transmitter resonators (30A') and (30B') largely cancel each other out.

[0198] When the power signals of the transmitter resonators 30A', 30B' are not 180 degrees out of phase, with one of the transmitter resonators 30A', 30B' experiencing the other of the transmitter resonators 30A', 30B' as a parasitic, the controller 22 for each of those transmitter resonators 30A', 30B' can increment the phase of the signal from each corresponding oscillator while measuring the power transmitted by the corresponding transmitter resonator 30A', 30B' using the corresponding transmitter power sensor 24B. The controller 22 can then search for the adjusted oscillator phase that provides the maximum power transferred through the corresponding transmitter resonator 30A', 30B' and then set the oscillator phase to that corresponding phase.

[0199] As discussed above, the configuration of frequency and phase for each resonant receiver system ensures that both resonant receiver systems receive the maximum transmitted power, whether they are of similar or different sizes. In an overall embodiment, there may be many transmitter resonators and several different resonant receiver subsystems may receive power, each receiving power from its own corresponding individual group of transmitter resonators at a frequency and phase selected by a controller corresponding to the transmitter resonators in the group. Adjacent transmitter resonators transmitting power to different receiver subsystems may operate 180° out of phase as a result of maximizing the power transfer of each of the adjacent transmitter resonators. The process of maximizing the power transfer adjusts the phase of the oscillator. Because the impedances of the various transmitter modules are complex with small variations in resistance, inductance, and capacitance, the phase angles of the different oscillators at the point of maximum power transfer may not be perfectly equal (or may differ by exactly 180°) even though the power signals at the transmitter resonators are actually equal (or may differ by exactly 180°).

[0200] To the extent that system (10') includes one circuit with an air gap between the primary and secondary sides, any power transfer measured or maximized in the transmitter resonator, for example at point (24E) in Figure 6 based on measurements by the transmitter power sensor (24B), may also be measured or maximized in the secondary circuit, for example at point (44C) in Figure 7 based on measurements by the receiver power sensor (44A). That measurement may be provided by the transmitter power sensor (24B) to the controller (42) of the receiver module (40), which then transmits the measurement to the controller (22) of the transmitter module (20) by one of the means previously described.

[0201] The concept of a multi-transmitter near-field resonant wireless power transfer system has been described above with reference to a system (10') configured for simultaneous capacitive and inductive power transfer according to an adjustable transmission mode ratio at a variable resonant power signal oscillation frequency. In a more general embodiment, the multi-transmitter near-field resonant wireless power transfer system need not specifically be a bimodal system, but may be a purely capacitive or purely inductive power transfer system.

[0202] In a further aspect shown in the flow chart of FIG. 15, a wireless near-field method

[1100] for transmitting power from multiple transmitter subsystems (12') to a single resonant receiver subsystem (14) at a variable resonant power signal oscillation frequency includes the step

[1110] of providing a multiple transmitter subsystem (12') having a plurality of mutually independent transmitter resonators (30A')-(30I'), each of the transmitter resonators being driven by a corresponding transmitter module (20A')-(20I'), each of the transmitter modules (20A')-(20I') being independently configurable to one of a plurality of pre-defined power signal oscillation frequencies in a pre-defined frequency band; the step of placing a resonant receiver subsystem (14) having a single receiver resonator (50) overlapping with two or more of the transmitter resonators ((30D'), (30E'), (30G'), and 30H of FIG. 13A) proximate to the common transmit surface; the step of measuring an input impedance of each of the transmitter resonators (30A')-(30I'); and the step of setting a power signal to each of the plurality of mutually independent transmitter resonators (30A')-(30I') to one of an off state or an activated state based on the corresponding measured resonator input impedance.

[0203] The method

[1100] may further include a step

[1150] of selecting a power signal oscillation frequency of a corresponding transmitter resonator (resonators (30D'), (30E'), (30G'), and (30H') of FIG. 13A) from among a plurality of pre-set power signal oscillation frequencies based on the measured input impedance of each of the activated transmitter resonators (resonators (30D'), (30E'), (30G'), and (30H) of FIG. 13A).

[0204] The method

[1100] may further include a step

[1160] of setting the power signal of each activated transmitter resonator ((30D'), (30E'), (30G'), and (30H') in FIG. 13A) to a corresponding selected frequency.

[0205] The method

[1100] may further include a step

[1170] of adjusting the phase of the power signal applied to each corresponding transmitter resonator (resonators (30D'), (30E'), (30G'), and (30H) of FIG. 13A) to a phase at which power transmission through the transmitter resonators ((30D'), (30E'), (30G'), and (30H') of FIG. 13A) is substantially maximized.

[0206] In a further aspect shown in the flow chart of FIG. 16, a wireless near-field method

[1200] for transmitting power at variable resonant power signal oscillation frequencies from multiple transmitter subsystems (12') to a single resonant receiver subsystem (14) includes the step of providing

[1210] a multiple transmitter subsystem (12') comprising a plurality of mutually independent transmitter resonators (30A')-(30I'), each of the transmitter resonators being driven by a corresponding transmitter module (20A')-(20I'), each of the transmitter modules (20A')-(20I') being independently configurable to one of a plurality of pre-defined power signal oscillation frequencies in a pre-defined frequency band, the step of providing a multiple transmitter resonator (30A')-(30I') having a plurality of mutually independent transmitter resonators (30A')-(30I'), each of the transmitter modules (20A')-(20I') ... the step of providing a multiple transmitter resonator (30A')-(30I') having a plurality The method includes a step

[1210] of positioning a resonant receiver subsystem (14) having a single receiver resonator (50) overlapping with two or more of the transmitter resonators ((30D'), (30E'), (30G'), and (30H') of FIG. 13A) proximate to the common transmission surface; a step

[1220] of measuring the power consumed by each of the transmitter resonators (30A')-(30I') from a test signal; and a step

[1140] of setting a power signal to each of the plurality of mutually independent transmitter resonators (30A')-(30I') to one of an off state and an activated state based on the corresponding measured resonator test power consumption.

[0207] The method

[1200] may further include a step

[1250] of selecting a power signal oscillation frequency of a corresponding transmitter resonator (resonators (30D'), (30E'), (30G'), and (30H) of FIG. 13A) from among a plurality of pre-set power signal oscillation frequencies based on the measured test power consumed by each of the activated transmitter resonators (resonators (30D'), (30E'), (30G'), and (30H) of FIG. 13A).

[0208] The method

[1200] may further include a step

[1260] of setting the power signal of each activated transmitter resonator ((30D'), (30E'), (30G'), and (30H) in FIG. 13A) to a corresponding selected frequency.

[0209] The method

[1200] may further include a step

[1270] of adjusting the phase of the power signal applied to each corresponding transmitter resonator (resonators (30D'), (30E'), (30G'), and (30H) of FIG. 13A) to a phase at which power transmission through the transmitter resonators ((30D'), (30E'), (30G'), and (30H) of FIG. 13A) is substantially maximized.

[0210] In a further aspect shown in the flow chart of FIG. 17, a wireless near-field method

[1300] for transmitting power from a multiple transmitter subsystem (12') to two or more receiver subsystems (14A), (14B) (in FIG. 14) at variable resonant power signal oscillation frequencies includes the step

[1310] of providing a multiple transmitter subsystem (12') having a plurality of mutually independent transmitter resonators (30A')-(30I') (in FIG. 14), each of the transmitter resonators being driven by a corresponding transmitter module (20A')-(20I') (see FIG. 13B), each transmitter module (20A')-(20I') independently tuned to one of a plurality of pre-defined power signal oscillation frequencies in a pre-defined frequency band. the step of arranging two or more resonant receiver subsystems (14A), (14B), each including a single receiver resonator overlapping with one or more of the transmitter resonators (transmitter resonators (30A'), (30B') of FIG. 14 ), proximate to the common transmission surface; the step of measuring the input impedance of each of the transmitter resonators (30A'), (30B'); and the step of setting a power signal to each of the plurality of mutually independent transmitter resonators (30A'), (30I') to one of an off state and an activated state based on the corresponding measured resonator input impedance.

[0211] The method

[1300] may further include a step

[1350] of selecting a power signal oscillation frequency for the corresponding transmitter resonator (30A'), (30B') from among a plurality of pre-set power signal oscillation frequencies based on the measured input impedance of each of the activated transmitter resonators (resonators (30A'), (30B') of FIG. 14).

[0212] The method

[1300] may further include the step

[1360] of setting the power signal of each activated transmitter resonator (30A'), (30B') to a corresponding selected frequency.

[0213] The method

[1300] may further include a step

[1370] of adjusting the phase of the power signal applied to the corresponding transmitter resonators (30A'), (30B') to a phase at which power transmission through the transmitter resonators (30A'), (30B') (in FIG. 14) is substantially maximized.

[0214] In a further aspect shown in the flow chart of FIG. 18, a wireless near-field method

[1400] for transmitting power at variable resonant power signal oscillation frequencies from multiple transmitter subsystems (12') to two or more receiver subsystems (14A), (14B) (in FIG. 14) includes the step

[1410] of providing a multiple transmitter subsystem (12') comprising a plurality of mutually independent transmitter resonators (30A')-(30I') (in FIG. 14), each of the transmitter resonators being driven by a corresponding transmitter module (20A')-(20I') (see FIG. 13B), each of the transmitter modules (20A')-(20I') being independently set to one of a plurality of pre-defined power signal oscillation frequencies in a pre-defined frequency band. the step of arranging two or more resonant receiver subsystems (14A), (14B), each including a single receiver resonator overlapping with one or more of the transmitter resonators (transmitter resonators (30A'), (30B') of FIG. 13), proximate to the common transmission surface; the step of measuring the power consumed by each of the transmitter resonators (30A'), (30I') from a test signal; and the step of setting a power signal to each of the plurality of mutually independent transmitter resonators (30A'), (30I') to one of an off state and an activated state based on the corresponding measured resonator test power consumption.

[0215] The method

[1400] may further include a step

[1450] of selecting a power signal oscillation frequency for the corresponding transmitter resonator (30A'), (30B') from among a plurality of pre-set power signal oscillation frequencies based on the measured input impedance of each of the activated transmitter resonators (resonators (30A'), (30B') of FIG. 14).

[0216] The method

[1400] may further include the step

[1460] of setting the power signal of each activated transmitter resonator (30A'), (30B') to a corresponding selected frequency.

[0217] The method

[1400] may further include a step

[1470] of adjusting the phase of the power signal applied to the corresponding transmitter resonators (30A'), (30B') to a phase at which power transmission through the transmitter resonators (30A'), (30B') (in FIG. 14) is substantially maximized.

[0218] In a further embodiment described with reference to Figures 20A and 20B, 21A and 21B, and 22A and 22B, and based on the systems of Figures 1-10 and 12-14, a near-field resonant wireless power transfer system (10") for wirelessly transferring power from a solar cell (420) to a power load (70") is shown as a schematic diagram in Figure 19A. An accented numbering scheme is used for the labels in Figure 19A to clarify the similarities with Figures 13A and 13B, which in turn clarify the similarities with Figures 6 and 7. With this numbering scheme, DC power is provided from the solar cells (420) via the power conditioning unit (PCU) (430) to the transmitter module (20"). Beyond converting the DC voltage and current to a level that can be further transmitted by the power amplifier (26B"), the PCU (430) also provides appropriately regulated levels of voltage and current to drive the remaining system components, including small signal electronics, in the transmitter module (20"). The PCU (430) represents an adaptively changing load to the solar cells (420) to match the changing power provided by the solar cells (420) and the changing output impedance presented by the solar cells (420) to the PCU (430). This allows the PCU (430) to always absorb power from the solar cells (420) at the maximum possible rate and temperature despite fluctuations in that power from the solar cells (420).

[0219] An oscillator (26A") may be used to modulate the power amplifier (26B") at a frequency compatible with wireless power transmission, as already mentioned above. The power amplifier (26B") may be of the same design as the amplifier (26B) shown in FIG. 8, with power from the PCU (430) being supplied as a DC voltage (127E) instead of VDD. In an alternative embodiment, the power amplifier (26B") may be suitably provided with circuitry to maintain oscillation by itself, as is well known in the art of wireless systems, whereby the oscillator (26A") may be omitted.

[0220] Power may be transmitted to the transmitter resonator (30") through a transmit tuning network (28"), which in FIG. 19A is an integration of the signal conditioning and tuning components (26C, 26D, 26E, and 26F) of FIG. 6. The transmitter resonator (30") may have a surface area that may be at least a major fraction of the area of ​​the dynamic solar radiation receiving surface of the solar cell (420). All of these components of the transmitter module (20") are under the control of the controller (22"), just as the corresponding components of the transmitter module (20) of FIG. 6 are under the control of the controller (22"). For clarity, not all components of the transmitter module (20") are shown in FIG. 19A. The sensors and detectors (24A, 24B, 24C, and 24D of FIG. 6) may be present in the transmitter module (20") in an equivalent form and connected to the controller (22"), and may play the same role as in FIG. 6.

[0221] Power may be wirelessly transferred from the transmitter module (20") to the receiver module (40") via the transmitter resonator (30") and the receiver resonator (50"). From the receiver module (40"), power may be transferred to a DC load (70"). The transmission of power between the transmitter resonator (30") and the receiver resonator (50") may be by near-field wireless transmission, as described in connection with Figures 6 to 10. As in Figure 20, near-field wireless power transfer is not limited to being two-way, but may be purely capacitive or purely inductive.

[0222] The receiver module (40") may have the same components as the receiver (40) of FIG. 7. For clarity, a reduced set of those components is shown in FIG. 19A. The sensor (44A) and detector (44B) of FIG. 7 are not shown in equivalent form in FIG. 19A, but may be present. The receiver tuning network (48") of FIG. 19A may be an integration of a compensation network (46A), a matching network (46B), a rectifier (46D), and a filter (46C). Power may be transferred from the receiver tuning network (48") to a load management (46E"), both of which may be under the control of the receiver controller (42").

[0223] Referring to FIG. 19A and building on the systems of FIGS. 1-10, a near-field resonant wireless power transfer system 10″ is presented for wirelessly transferring power from a power source, which in this exemplary embodiment is a solar cell (420), to a power load (70″). A double accent numbering system is used in the labels of FIG. 19A to make the similarities with FIGS. 6 and 7 clear. By this numbering, DC power is provided from the solar cells (420) through a power conditioning unit (PCU) (430) to the transmitting module (20"). The PCU (430) provides appropriately regulated levels of voltage and current to drive the remainder of the system components including, for example, small signal electronic components within the transmitting module (20"), in addition to converting the DC voltage and current to levels suitable for conversion to a radio frequency signal for further transmission by the power amplifier (26B"). The PCU (430) represents an adaptively varying load to the solar cells (420) to accommodate the variable power provided by the solar cells (420) and the variable output impedance presented to the PCU (430) by the solar cells (400). This allows the PCU (430) to absorb the greatest possible percentage of power from the solar cells (420) at any time and at any temperature, despite variations in that power from the solar cells (420).

[0224] The oscillator (26A") may be used to modulate the power amplifier (26B") at a frequency compatible with wireless power transmission, as already mentioned above. The power amplifier (26B") may be of the same design as the amplifier (26B) shown in FIG. 8, with power from the PCU (430) being supplied as a DC voltage (127E) instead of VDD. In an alternative embodiment, the power amplifier (26B") may be suitably provided with circuitry to maintain oscillation by itself, as is well known in the art of wireless systems, thereby allowing the oscillator (26A") to be omitted.

[0225] Power may be transmitted to the transmitter resonator (30") through a transmit tuning network (28"), which in FIG. 19A is an integration of the signal conditioning and tuning components (26C, 26D, 26E, and 26F) of FIG. 6. The transmitter resonator (30") may have a surface area that may be at least a major fraction of the area of ​​the dynamic solar radiation receiving surface of the solar cell (420). All of these components of the transmitter module (20") are under the control of the controller (22"), just as the corresponding components of the transmitter module (20) of FIG. 6 are under the control of the controller (22"). For clarity, not all components of the transmitter module (20") are shown in FIG. 19A. The sensors and detectors (24A, 24B, 24C, and 24D of FIG. 6) may be present in the transmitter module (20") in an equivalent form and connected to the controller (22"), and may play the same roles as those already described in connection with FIG. 6.

[0226] Power may be wirelessly transferred from the transmitter module (20") to the receiver module (40") via the transmitter resonator (30") and the receiver resonator (50"). From the receiver module (40"), power may be transferred to a DC load (70"). The transmission of power between the transmitter resonator (30") and the receiver resonator (50") may be by near-field wireless transmission, as described in connection with Figures 6 to 10. As in Figure 19A, near-field wireless power transfer is not limited to being two-way, but may be purely capacitive or purely inductive.

[0227] The receiver module (40") may have the same components as the receiver (40) of FIG. 7. For clarity, a reduced set of those components is shown in FIG. 19A. The sensor (44A) and detector (44B) of FIG. 7 are not shown in equivalent form in FIG. 19A, but may be present. The receiver tuning network (48") of FIG. 19A may be an integration of a compensation network (46A), a matching network (46B), a rectifier (46D), and a filter (46C). Power may be transferred from the receiver tuning network (48") to a load management (46E"), both of which may be under the control of the receiver controller (42").

[0228] Regarding rectifier 46D, which is shown in more detail in FIG. 7, the input impedance of this device depends directly on the load seen by the output of the device.

[0229] In operation, the near field resonant wireless power transfer system (10") may function similarly to the near field resonant wireless power transfer system (10) of Figures 1 and 6-10, except that the applied voltage VDD of each power amplifier (26B") is replaced by a power signal from a power conditioning unit (PCU) (430), which in turn receives its power from an associated power source, which in this embodiment is a solar cell (420).

[0230] In another embodiment, the power conditioning unit (430) may be omitted from the system shown in FIG. 19A and the power transfer system (10") is instead configured or operated to function as a power conditioning system as well. This may be accomplished by configuring the controller (22"), for example but not limited to in software, to adjust the input DC equivalent resistance of the power amplifier (26B") based on the power level measured by the power sensor (24B) of FIG. 6. The term "input DC equivalent resistance" is used to represent the ratio of DC voltage to DC current at the DC terminals of the power amplifier (26B). The controller (22") will make adjustments based on the power measurements, but it is expected that the maximum power point of the transferred power will be achieved when the input impedance of the power amplifier (26B") matches the output impedance of the solar cell (420). In this embodiment, the system (10") functions as what is known in the industry as a "maximum power point tracker" and ensures that power is always transferred at a rate more suitable for the load consuming the power than would be achieved if the delivery of power was not regulated. In another embodiment, the controller (22") may be configured to measure the output impedance of the power source, which in this embodiment is a solar cell (420), and then adjust the input impedance of the power amplifier (26B") based on the measured output impedance of the solar cell (420).

[0231] In addition to adjusting the input impedance of the power amplifier (26B"), the controller (22") may adjust one or more of the settings of the transmitter tuning network (28") and the frequency of the oscillator (26A"). Additionally, the transmitter controller (22") may make adjustments as already mentioned above based on measurements by the load detector (24A) shown in FIG. 6, which shows the circuitry of the transmitter modules (20 and 20") in more detail. The load detector (24A) senses the effect of the load (70") at point (24E) in FIG. 6.

[0232] The receiver controller (42") may adjust one or more of the settings of the receiver tuning network (48") and the load management system (46E") to improve the efficiency of power transfer based on measurements by the receiver power sensor (44A) and the load detector (44B) (both shown in FIG. 7).

[0233] In considering the power conditioning functionality of the system (10"), it will be understood that there is no a priori reason why the power transmission functionality of the system must be limited to near-field wireless transmission across an air gap as in FIG. 19A. Thus, in another embodiment, a power conditioning unit (410) is shown in FIG. 19B based on the elements of the system (10") of FIG. 19A. The transmitter tuning network (28") is in direct electrical communication with the receiver tuning network (48") via a suitable non-air-gap connection (60"). This communication is via radio frequency power signals and constitutes the power transmitted in and by the system. Electronic components of suitable reactance may be employed in well-known configurations to decouple any DC voltage and current levels in the transmitter module (20") from such levels in the receiver module (40"). The transmitter resonator (30") and receiver resonator (50") are not present in this embodiment and are made unnecessary by the direct communication connection between the transmitter tuning network (28") and the receiver tuning network (48").

[0234] The function of the power transmission system of Figures 19A and 19B as a power conditioning system can be better understood by considering Figure 19B in particular, where the concepts of power conditioning are simplified by the absence of the transmitter resonator (30") and receiver resonator (50"), but they apply equally when these resonators are present (as in Figure 19A). The system of Figures 19A and 19B has four independent control parameters that can be adjusted during operation to regulate the power delivered to the receiving module (40") and thereby to the load (70"). Typical commercial power conditioning units are commonly known as "boost converters" because they raise their output voltage above that of the source voltage. These devices have only two control parameters.

[0235] The first independent control parameter that can be adjusted during operation to regulate the power delivered to the receiver module (40") and thereby to the load (70") is the oscillation frequency of the power amplifier (26B"), which is adjustable by the controller (22A") of the oscillator (26A").

[0236] A second independent control parameter that may be adjusted during operation to regulate the power being transmitted to the receive module (40"), and thereby transferred to the load (70"), is the output load of the rectifier (46D) of the receive module (40"). That output load, in turn, directly determines the input impedance of the rectifier (46D) and thereby the input impedance of the receiver module (40"). This, in turn, is the load seen by the transmitter module (20"), which directly determines the input DC equivalent resistance of the power amplifier (26B"). Manipulation of the output load of the rectifier (46D) is accomplished through the load management system (46E") of the receiver module (40") (see FIG. 19A) under the control of the receiver controller (42"). This second independent control parameter, while a property of the receiver module, essentially controls the load seen by the power supply. The control point for manipulating this parameter is the load management system (46E") of the receiver module (40").

[0237] The third and fourth independent control parameters that can be adjusted during operation to regulate the power delivered to the receiver module (40") and thereby to the load (70") are the characteristics of the rectifier (46D) (see FIG. 7) and the power amplifier (26B") (FIG. 19A) of the receiver module (40"), which are similar in nature but completely independent of each other. Both the rectifier (46D) and the power amplifier (26B") comprise multi-terminal amplifying devices and rely on the modulation of the passage of current between two terminals through the multi-terminal device by a voltage signal applied to a third terminal of each device. The simplest multi-terminal amplifying device that can be used in each of the rectifier (46D) and power amplifier (26B") is a transistor. This allows for a phase difference to exist between the voltage signal and the current signal generated by or within the device. That voltage-current phase difference is adjustable via the applied voltage. The rectifier (46D) may be an adjustable phase radio frequency rectifier whose voltage-current phase difference can be adjusted via the receiver controller (42"). In the case of the power amplifier (26B"), the voltage-current phase difference may be adjusted via the transmitter controller (22"). The rectifier (46D) may typically comprise a differential self-synchronous radio frequency rectifier. The rectifier (46D) may particularly comprise a differential class F self-synchronous radio frequency rectifier.

[0238] The examples of Figures 19A and 19B are based on transmitting power from a solar cell and therefore from a solar array, where the power delivered by the solar cell (420) can vary rapidly down to zero depending on the sunlight. There are many other sources of power that suffer from output fluctuations, both in terms of power and generated voltage. These include electricity generating turbines, wind turbines, and various batteries and accumulators. Wind turbines vary widely in the amount of power they generate, and various batteries can have a wide range of power depletion curves. Given the efficiency of the system's power transfer, any of these systems (10") and (410) may be configured to receive power from, for example, but not limited to, a commercially available battery having a slow open circuit voltage decay curve. The load management system (46E") may be configured to vary the input DC equivalent resistance of the power amplifier (26B") as already described above, and the controllers (22" and 42") may be configured to provide a requested voltage value to the load (70") until the requested voltage cannot be further maintained by the transmitted power and the adjustability of the parameters of the systems (10" and 410).

[0239] FIG. 19A and the associated text correspond to near-field wireless transmission from a single solar cell (420) to a single load (70"), typically a battery. In practical implementations of larger solar cell power systems, an array of batteries will typically be employed, and thus a power transfer scheme similar to that described with reference to FIGS. 12, 13A, and 13B may be employed, with multiple transmitter subsystems and typically a single receiver subsystem. This situation is illustrated in FIGS. 20A and 20B, which are exploded front and rear views, respectively, of a solar panel (400), which includes a , a transparent solar cover (440) having one near-field wireless power transmission subsystem per solar cell (420), thereby providing, by way of example, 60 near-field wireless power transmission subsystems (16), each transmission subsystem (16) comprising a transmitter resonator (30"), a transmitter module (20"), and a power conditioning unit (430) as described with reference to FIG. 19A. To avoid confusion, the transmission subsystems (16) are not labeled in FIG. 19A but are shown and labeled in FIGS. 20B, 21B, and 22B, as described further below.

[0240] In one embodiment, individual solar cells of a solar panel comprised of multiple solar cells are coupled to a power transmission and management system to enable cell-level power management. Power management at each individual cell allows for optimized power collection at each cell, thereby improving the efficiency of the entire solar panel system. In such an embodiment, the effects of individual cell failures or poor connections between cells are mitigated. Power collection at the individual cell level allows for maximum power to be obtained even in non-ideal conditions such as rain or shade, or when debris covers parts of the solar panel.

[0241] To avoid confusion, only one near-field wireless power transfer subsystem (16) is labeled in FIG. 20B. In FIGS. 20A and 20B, the transmitter resonator (30") of each transmitting subsystem (16) may be disposed on the backside of its corresponding solar cell (420). When viewed from the front of the panel in FIG. 20A, the flat area of ​​the solar cell represents the activated solar radiation receiving and energy converting semiconductor device itself and is accordingly labeled (420), while when viewed from the back in FIG. 20B, the flat area of ​​the device represents the transmitter resonator and is accordingly labeled (30"). The transmitter resonator (30") may have a surface area that may be at least a major fraction of the extent of the dynamic solar radiation receiving surface of the solar cell (420). The transmitting module (20") and power conditioning unit (430) of each near-field wireless power transfer subsystem (16) are integrated together in FIG. 20B and labeled (450). To avoid confusion, the integrated components (450) are not labeled in FIG. 19A, but are shown and labeled as a unit in FIGS. 20B, 21B, and 22B, as described further below. A single receiver resonator (50") may be fitted into the frame (460) of the solar panel (400). A single receiver module (40") may be attached directly to the back of the receiver resonator (50").

[0242] In operation, the near field resonant wireless power transfer system (10") can function similarly to the near field resonant wireless power transfer system (10) of Figures 12, 13A, and 13B, except that the voltage VDD applied to each of the power amplifiers (26B") is replaced by a power signal from a power conditioning unit (PCU) (430), which in turn receives its power from an associated solar cell (420).

[0243] In another embodiment of the system of Figures 20A and 20B, the frame (460) may be configured to be a suitable receiver resonator for receiving power from all of the transmitter resonators (30"), and the receiver module (40") may be placed on the frame (460). In this embodiment, the plate in the frame is not a resonator, but may simply be a flat sheet of non-conductive material.

[0244] In another embodiment, a solar panel (400'), shown in front and back views in Figures 21A and 21B, respectively, has each near-field wireless power transmission subsystem transmit power to one near-field wireless power receiving subsystem. The frame (460I) is shown filled with an opaque plate (470), but the plate (470) need not be part of either the near-field electric or magnetic circuits. For clarity, the same component numbers are adopted for the transmitting side as in Figures 20A and 20B. For the receiving side, the numbering of Figure 19A is adopted. Again, only one receiving device is shown to avoid confusion.

[0245] In operation, the solar panel arrangement (400') of Figures 21A and 21B has individual transmitter modules (20") hardwired (not shown) to enable them to be in phase, thereby minimizing power loss during transmission. In other embodiments, the transmitter modules (20") may be independent and function as described in Figures 14, 17, and 18.

[0246] In yet another embodiment, shown as a solar panel array (400") in front and back views in Figures 22A and 22B, respectively, an array of, for example, 25 solar cells is shown, arranged in five rows of five cells (420) each. Each solar cell (420) has at its rear a transmitter resonator (30") and a unit (450) containing its corresponding transmitter module (20") and power conditioning unit (430). At the bottom and top of the array, and between each two rows of solar cells, are receiver resonators (50") arranged in a plane substantially perpendicular to the plane of the solar cells (420), each receiver resonator (50") in wired electrical communication with its corresponding receiver module (40"). As with the previous solar panel embodiments, one instance of each component is labeled. Similar to the embodiments shown in Figures 20A and 20B, and Figures 21A and 21B, the solar panel array (400") may also have a frame (460) in some embodiments. For clarity, the frame (460) is not shown in Figures 22A and 22B.

[0247] In operation, the transmitter resonator (30") of a solar cell (420) in a particular row of the system (400") transmits power to both the receiver resonators (50") above and below it. However, in this embodiment, there is the additional mechanism of the various nearest neighbor receiver resonators (50") being resonantly coupled and sharing the collected power. Thus, the power collected by all receiver resonators (50") of the array can be tapped through any one or more of the various receiver modules (40"). In particular, the power collected by all receiver modules (40") may be tapped through only the bottom-most receiver module (40"), as an example. Any one of the receiver modules (40") on any resonator (50") can function as a receiver module collecting the power of the row of solar cells (420), but can also function as a transmitter module transmitting the collected power through its associated resonator (50") to another resonator (50") in its vicinity. This operation may be repeated down the array to transfer power to the bottom-most receiver module (40").

[0248] In another embodiment of the system of Figures 22A and 22B, a frame similar to the frame (460) of Figures 20A and 20B that surrounds the planar perimeter of the solar array of Figures 22A and 22B may be a receiver resonator that supports a receiving module (40") and may receive power from the various resonators (50"). In this manner, the total power generated by all solar cells (420) in the array may be received by the resonator frame (460) and tapped for further electrical transmission via the receiver module (40").

[0249] Power collection at the individual solar cell level may be achieved with wired connections, but the use of a wireless transmission system in the solar panel allows for a reduction in wiring and therefore manufacturing costs.

[0250] In a further aspect described with reference to the flowchart of FIG. 23, a method

[1500] for transmitting power from a photovoltaic cell (420) to a power load (70") is provided, the method comprising the steps of: converting power from the photovoltaic cell (420) into an oscillating power signal having an oscillating frequency in a transmitting module (20")

[1510] ; transmitting the power to a transmitter resonator (30") in wired electrical communication with the transmitting module (20") and configured to resonate at the oscillating frequency

[1520] ; and transmitting the power to a transmitter resonator (30") configured to resonate at the oscillating frequency and configured to resonate at the oscillating frequency using at least one of capacitive coupling and magnetic induction. The method includes a step of receiving power at a receiver resonator (50") arranged to receive power from the transmitter resonator (30") via one of the photovoltaic cells (420) and a step of receiving the power at a receiver module (40") in wired electrical communication with the receiver resonator (50")

[1540] , and a step of converting the received power into a direct current form via wired electrical communication with the electrical load (70")

[1550] . The method may further include a step of converting the voltage and current of the power from the photovoltaic cell (420) to a voltage and current compatible with the transmitter module (20") prior to converting the power into an oscillating power signal.

[0251] In a further embodiment of the method described with reference to FIG. 19A and the flow chart of FIG. 24, a method

[1600] for transmitting power from an array (400) of photovoltaic cells (420) to a power load (70") is provided, the method comprising the steps of: converting, in each transmitter module of a first plurality of corresponding transmitter modules (20"), power from each of the photovoltaic cells (420) of the array (400) into an oscillating power signal having an oscillating frequency

[1610] ; and transmitting the power of each transmitter module of the transmitter module (20") to a corresponding transmitter resonator (70") from a second plurality of transmitter resonators (30"); receiving power at a receiver resonator (50") configured to resonate at the oscillation frequency and arranged to receive power from the plurality of transmitter resonators (30") via at least one of capacitive coupling and magnetic induction; receiving the power at a receiver module (40") in wired electrical communication with the receiver resonator (50"); and converting the received power to a direct current form via wired electrical communication with the electrical load (70"). The method may further include converting the voltage and current of the power from each photovoltaic cell (420) to a voltage and current compatible with a corresponding transmitter module (20") prior to converting the power to an oscillating power signal. Receiving power at a receiver resonator (50") may also include receiving power at receiver resonators arranged around a planar periphery of the array of photovoltaic cells (400).

[0252] In a further embodiment of the method described with reference to FIG. 19A and the flow chart of FIG. 25, a method

[1700] for transmitting power from an array (400′) of photovoltaic cells (420) to a power load (70”) is provided, the method comprising the steps of: converting, in each transmitting module of a first plurality of corresponding transmitting modules (20”), power from each photovoltaic cell of the array (400′) into an oscillating power signal having an oscillating frequency

[1710] ; and transmitting the power from each transmitting module of the transmitting module (20”) to a corresponding transmitter resonator (30”) of a second plurality of transmitter resonators (30”), each transmitter resonator (30”) transmitting the power from each transmitting module of the transmitting module (20”) to a corresponding transmitter resonator (30”) of a second plurality of transmitter resonators (30”), receiving power from each transmitter resonator (30") in a corresponding receiver resonator (50") configured to resonate at the oscillating frequency

[1730] , each receiver resonator (50") further configured and arranged to receive power from the transmitter resonator (30") via at least one of capacitive coupling and magnetic induction; receiving power from each receiver resonator (50") in a corresponding receiver module (40") in wired electrical communication with the receiver resonator (50")

[1740] ; and converting the received power into a direct current form via wired electrical communication with the electrical load (70"). The method may further include converting the voltage and current of the power from each photovoltaic cell (420) to a voltage and current compatible with a corresponding transmitter module (20") prior to converting the power into an oscillating power signal.

[0253] In a further embodiment described with reference to FIG. 19A and the flow chart of FIG. 26, a method

[1800] for transmitting power from an array (400") of photovoltaic cells (420) to a power load (70") (of FIG. 19A) is provided, the method comprising the steps of: converting, in each transmitting module of a first plurality of corresponding transmitting modules (20"), power from each of the photovoltaic cells (420) of the array (400") into an oscillating power signal having an oscillating frequency; transmitting the power from each transmitting module of the transmitting modules (20") to a transmitter resonator (30") from among a second plurality of transmitter resonators (30"), each transmitter resonator (30") configured to resonate at the oscillating frequency; and transmitting the power from each transmitter resonator (30") to a transmitter resonator (30") from among a second plurality of transmitter resonators (30") configured to resonate at the oscillating frequency. receiving in any adjacent receiver resonator (30") from a third plurality of receiver resonators (50") arranged to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction; sharing the received power among the third plurality of receiver resonators (50"); and converting the power received from one or more of the third plurality of receiver resonators (50") into a direct current form via a corresponding one or more receiver modules via wired electrical communication; the method may further include converting the voltage and current of the power from each photovoltaic cell (420) into a voltage and current adapted to a corresponding transmitter module (20") before converting the power into an oscillating power signal.

[0254] FIG. 27A shows a representative portion (500) of an extended near-field wireless power distribution system in an electric vehicle having a conductive chassis (510). In this embodiment of the general system (10") of FIG. 19A, the power source is a rechargeable battery (520) rather than a solar cell (420), and the load (70") is an electric motor (530) rather than a battery as in FIG. 19A. The system shown in FIG. 14A may optionally include a power conditioning unit (430) as in FIG. 19A. In other embodiments, the transmitter modules may function in concert to provide power conditioning, as described above with reference to FIG. 19B.

[0255] The system shown in FIG. 27A and described in more detail below may operate by capacitive, inductive, or bimodal power transfer. With reference to FIG. 4B and FIG. 19A, the transmitter resonator (30") comprises a dielectric element (138) sandwiched between conductive antennas (132 and 134). With reference to FIG. 4B and FIG. 19A, the receiver resonator (50") comprises a dielectric element (158) sandwiched between conductive antennas (152 and 154). The transmitter module (20") is shown attached directly to the antenna (132), which also serves as a frame or holder for the battery (520). The transmitter module (20") may be electrically connected between the battery (520) and the transmitter resonator (30"). The receiver module (40") is shown attached directly to the electric motor (530). The receiver module (40") may be electrically connected between the receiver resonator (50") and the motor (530).

[0256] FIG. 27B shows a representative portion (500') of an extended near-field wireless power distribution system in an electric vehicle having a conductive chassis (510). In this embodiment of the general system (10") of FIG. 19A, the power source is again a rechargeable battery (520) rather than a solar cell (420) as in FIG. 27A, and the load (70") is an electric motor (530) rather than a battery as in FIG. 19A. The system shown in FIG. 27B may optionally include a power conditioning unit (430) as in FIG. 19A. In other embodiments, the transmitter module (20") and receiver module (40") may function together to provide power conditioning as described above with reference to FIG. 19B.

[0257] The system shown in FIG. 27B and described in more detail below may operate by capacitive, inductive, or bimodal power transfer. With reference to FIG. 4B and FIG. 19A, the transmitter resonator (30") comprises a dielectric element (138) sandwiched between conductive antennas (132 and 134). With reference to FIG. 4B and FIG. 19A, the receiver resonator (50") comprises a dielectric element (158) and a conductive antenna (152), the antenna (154) of FIG. 27A being absent from the resonator (50") in this embodiment. The transmitter module (20") is shown attached directly to the antenna (132), which also serves as a frame or holder for the battery (520). The transmitter module (20") may be electrically connected between the battery (520) and the transmitter resonator (30"). The receiver module (40") is shown mounted directly to the electric motor (530). In this embodiment, the receiver module (40") may be electrically connected between the motor (530) and the chassis (510). In this arrangement, there is sufficient coupling between the chassis (510) and the antenna (152) to transfer power with suitably high efficiency. Electrically conductive mechanical components of the system, i.e., components that have a structural function in the system, for example, carrying a load, may form part of the resonant structure of the power transfer system.

[0258] Although the embodiment shown in Figures 27A and 27B focuses specifically on power supplied to an electric motor (530) driving one of the vehicle's wheels, an equivalent arrangement may be implemented in any electrical subsystem of a vehicle using multiple appropriately adapted receiving modules (40") all powered by a transmitter module (20").

[0259] The arrangement of Figures 27A and 27B for power transfer from the battery to the vehicle's electrical subsystems eliminates much of the highly complex automotive wiring harnesses that present difficulties and contribute to significant manufacturing costs when manufacturing vehicles. The embodiment of Figures 27A and 27B, together with its extension to other electrical subsystems of the vehicle, may also be described as an "extended near field wireless power distribution system."

[0260] This arrangement can be extended beyond other wheels of an electric vehicle to headlights and other vehicle accessories including, but not limited to, interior lights, dashboard displays, gauges, digital electronics, navigation systems, warning systems, etc. The application is not limited to electric vehicles either. It can be applied to hybrid or internal combustion engine vehicles to provide power when and where it is needed. It can also be applied to other vehicles employing any electrical system that requires electrical power as well. Examples include, but are not limited to, motorized and non-motorized bicycles, aircraft, watercraft, and other vehicles employing on-board power sources. The battery or power source need not be limited to being on-board the vehicle. The principles described with respect to Figures 1-11, 19A-19B, and 27A-27B also apply to stationary and vehicular systems that require power to be provided from a stationary power source, such as, but not limited to, a fixed rail for powering a moving vehicle.

[0261] FIG. 28A shows an alternative embodiment of the general system (10") of FIG. 19A in a power supply system (600) for powering a computer monitor (610) positioned on a desk top (620), with power being supplied from a suitable source via a primary side (12) as per FIG. 1 and more specifically FIG. 6. In system (600), the transmit module (20") and transmit resonator (30") of FIG. 19A are both incorporated into the primary side (12). In the configuration of system (600), as per FIG. 19A, the receiver resonator (50") forms the base of the monitor (610). The receiver module (40") of FIG. 19A may be incorporated into the base of the monitor (610). Alternatively, the receiver module (40") of FIG. 19A may be incorporated within the monitor (610) itself. Referring to FIG. 4B, antenna (152) forms the bottom of the base of monitor (610) and is separated from antenna (154) by dielectric material (158).

[0262] The housing and structural frame (630) of the monitor (610) may be at least partially conductive and may function as one continuous conductor for electrically supplying a power signal from the antenna (154) through the receiver module (40") (see FIG. 19A) to the circuitry of the monitor (610) representing the load resonator (70") of FIG. 19A. Another electrical connector from the antenna (152) to the circuitry of the monitor (610) extends from the antenna (152) to the base of the monitor (610). In other embodiments, the housing and structural frame (630) of the monitor (610) may be a non-conductive polymer and another conductor extends from the antenna (154) to the circuitry of the monitor (610) representing the load resonator (70") of FIG. 19A.

[0263] As shown in another embodiment of a power supply system (600') for powering a computer monitor (610) in FIG. 28B, the base of the monitor (610) may comprise only the antenna (152) and the dielectric (158). In this embodiment, a metallic conductive portion of the monitor's housing or frame (630) serves as the antenna instead of the antenna (154), and the housing or frame (630) has sufficient coupling with the antenna (152) underlying the dielectric (158) to provide sufficiently efficient power transfer. The receiver module (40") of FIG. 19A may be integrated into the base of the monitor (610). Alternatively, the receiver module (40") of FIG. 19A may be integrated within the monitor (610) itself. The housing and structural frame (630) of the monitor (610) may function as one continuous electrical conductor to provide a power signal through the receiver module (40") to the circuitry of the monitor (610) representing the load resonator (70") of FIG. 19A.

[0264] The system (600) may optionally include a power conditioning unit (430) as in FIG. 19A. In some embodiments, the transmitting module (20") and the receiving module (40") may use near-field wireless power transfer but function in conjunction to provide power conditioning as described with reference to FIG. 19A. The near-field wireless power transfer system of FIG. 28A eliminates the need for cumbersome power cables to power the monitor (610) and employs the mechanical structural elements of the system as integral electrical / electronic components in the power transfer arrangement.

[0265] As described with reference to the flow chart of FIG. 29 and the systems of FIGS. 19A and 19B, there is provided a method

[2000] for transmitting power from a DC power source (420) to a power load (70"), the method comprising the steps of: providing a power transmission system (10", 410) in wired electrical communication with the power source (420), the power transmission system (10", 410) comprising an oscillator (26A") capable of oscillating at an oscillating frequency, a power amplifier (26B") and a transmitter tuning network (28"), both under the control of a transmitter controller (22"), a receiver tuning network (48") and a load management system (46E"), both under the control of a receiver controller (42"), the receiver tuning network and load management system (46E") being in wired electrical communication with the power load (70"), the power amplifier (26B") having a power supply (420) and a power management system; converting power from the power source (420) into an oscillating power signal having an oscillating frequency in the power amplifier (26B"); transmitting the power signal from the power amplifier (26B") to the load management system (46E") via the transmitter tuning network and the receiver tuning network under the control of the transmitter controller; adjusting at least one of the oscillating frequency, the input DC equivalent resistance of the power amplifier (26B"), the transmitter tuning network (28"), the receiver tuning network (48"), and the load management system (46E") to change a power transfer rate; and converting the power received by the load management system (46E") into a direct current form via wired electrical communication with a power load (70").

[0266] Transmitting the power signal through the transmitter tuning network (28") and the receiver tuning network (48")

[2030] may include transmitting power through wired or wireless communication. Transmitting power through wireless communication may include transmitting power through near-field wireless communication. Transmitting power through near-field wireless communication may include transmitting power through at least one of capacitive coupling and inductive coupling. Transmitting power from a DC power source (420) may include transmitting power from at least one solar cell (420). Transmitting power from a DC power source may include transmitting power from at least one battery. Transmitting power from a DC power source may include transmitting power from a power source with a fluctuating voltage.

[0267] In another embodiment, described with further reference to the flowchart of FIG. 30 and the systems of FIGS. 19A and 19B, a method

[2100] for transmitting power from a DC power source (420) to a power load (70") is provided, the method comprising the step of providing

[2110] a power transmission system (10", 410) in wired electrical communication with the power source (420), the power transmission system (10", 410) comprising a tunable phase radio frequency (RF) power source in wired electrical contact with the power load (70"). The method includes the steps of: including a radio frequency power amplifier (26B") in radio frequency communication with a rectifier (46D) (see FIG. 7); converting power from the DC power source (420) to a radio frequency oscillating power signal in the power amplifier (26B")

[2120] ; converting the radio frequency oscillating power signal in the rectifier (46D)

[2130] ; and adjusting efficiency of power transfer by adjusting current-voltage phase characteristics of the rectifier (46D)

[2140] . Providing the adjustable phase radio frequency rectifier may include providing a differential self-synchronous radio frequency rectifier (46D).

[0268] The method

[2100] may further include adjusting an efficiency of power transfer by adjusting a DC equivalent input resistance of the power amplifier (26B"). The step

[2110] of providing the power transfer system (10", 410) may include providing a load management system (46E") in wired communication between the rectifier (46D) and the power load (70"). Adjusting the DC equivalent input resistance of the power amplifier (26B") may include adjusting an input impedance of the rectifier (46D) by adjusting the load management system (46E"). Adjusting the load management system (46E") may include automatically adjusting the load management system (46E").

[0269] The method

[2100] may further include adjusting efficiency of power transfer by adjusting a current-voltage phase characteristic of the power amplifier (26B"). The step

[2110] of providing the power transfer system (10", 410) may include providing a transmitter controller (22") in communication with the power amplifier (26B") to control the power amplifier (26B"). The adjustment of the current-voltage phase characteristic of the power amplifier (26B") may be performed by the transmitter controller (22"). The adjustment of the current-voltage phase characteristic of the power amplifier (26B") may be performed automatically by the transmitter controller (22").

[0270] The method

[2100] may further include a step of adjusting the efficiency of power transfer by changing the vibration frequency of the power amplifier (26B'').

[0271] The step of providing a power transfer system (10", 410)

[2110] may include providing a receiver controller (42") in communication with a rectifier (46D) to control the rectifier (46D). Adjustment of a current-voltage phase characteristic of the rectifier (46D) may be performed by the receiver controller (42"). Adjustment of a current-voltage phase characteristic of the rectifier (46D) may be performed automatically by the receiver controller (42").

[0272] The step of providing a power transmission system (10", 410)

[2110] may include providing a power amplifier (26B") in direct wired radio frequency communication with an adjustable phase radio frequency rectifier (46D) (via connection (60") of FIG. 19B). The step of providing the power transmission system (10", 410)

[2110] may include providing a power amplifier (26B") in wireless near-field radio frequency communication with the adjustable phase radio frequency rectifier (46D).

[0273] The step of providing the power transfer system (10", 410)

[2110] may include providing a transmitter resonator (30") in wired radio frequency communication with the power amplifier (26B"), and a receiver resonator (50") in wired radio frequency communication with the radio frequency rectifier (46D). The method

[2100] may further include operating the transmitter resonator (30") and the receiver resonator (50") in wireless near-field radio frequency communication with each other. The step of providing the power transfer system (10", 410)

[2110] may include providing a power amplifier (26B") in at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication with the rectifier (46D). The step of providing the power transmission system (10", 410)

[2110] may include providing a power amplifier (26B") in two-way wireless near-field communication with the adjustable rectifier (46D).

[0274] The method

[2100] further includes providing a power conditioning unit (430) electrically disposed between the power source (420) and the power transmission system (10"), and adjusting the power conditioning unit (430) to adjust at least one of a current and a voltage from the power source (420) to improve efficiency of power transmission.

[0275] Based on a more detailed consideration of the system of FIGS. 19A and 19B, and with reference to FIG. 7, a generalized electrical transmission system (10", 410) for supplying electrical power from a DC power source (420) to a power load (70") comprises a radio frequency power amplifier (26B") in wired electrical communication with said power source (420) and configured to convert a DC voltage from said power source (420) into an AC voltage signal having an oscillating frequency, and a radio frequency power amplifier (26B") in wired electrical contact with said power load (70") and configured to convert a DC voltage from said power source (420) into an AC voltage signal having an oscillating frequency. the adjustable phase radio frequency rectifier in communication with the rectifier (46D), the adjustable phase radio frequency rectifier configured to receive power transmitted from the power amplifier (26B"), and a receiver controller (42") in communication with the rectifier (46D), the receiver controller (42") configured to adjust an efficiency of power transfer from the power amplifier (26B") to the rectifier (46D) by adjusting a current-voltage phase characteristic of the rectifier (46D). The receiver controller (42") may be configured to automatically adjust the current-voltage phase characteristic of the rectifier (46D). The rectifier may be a differential self-synchronous radio frequency rectifier.

[0276] The power transmission system (10", 410) may further include a power signal load management system (46E") in wired communication with the power load (70") and disposed in a power signal direction between the power load (70") and the rectifier (46D), the load management system (46E") configured to increase efficiency of power transmission by adjusting an input impedance of the rectifier (46D). The load management system (46E") may be configured to automatically adjust the input impedance of the rectifier (46D).

[0277] The power transfer system (10", 410) may further include a transmitter controller (22") in communication with the power amplifier (26B"), the transmitter controller (22") configured to increase efficiency of power transfer by adjusting a current-voltage phase characteristic of the power amplifier (26B"). The transmitter controller (22") may be configured to automatically adjust the current-voltage phase characteristic of the power amplifier (26B") to increase efficiency of power transfer.

[0278] The power transfer system (10", 410) may further include an oscillator (26A") in communication with an oscillator (26B") and a transmitter controller (22"), said transmitter controller (22") may be configured to adjust the vibration frequency via the oscillator (26A").

[0279] The power amplifier (26B") may be in direct wired radio frequency communication with an adjustable phase radio frequency rectifier (46D) (via connection (60") in FIG. 19B). The power amplifier (26B") may be in wireless near-field radio frequency communication with the adjustable phase radio frequency rectifier (46D). The power transfer system (10", 410) may include a transmitter resonator (30") in wired radio frequency communication with the power amplifier (26B"), and a receiver resonator (50") in wired radio frequency communication with the rectifier (46D). The transmitter resonator (30") and the receiver resonator (50") may be in wireless near-field radio frequency communication with each other. The power amplifier (26B") may be in communication with the rectifier (46D) by at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. The power amplifier (26B") may be in two-way near-field wireless radio frequency communication with the rectifier (46D).

[0280] The power transfer system may further include a power conditioning unit (430) electrically disposed between the power source (420) and the power amplifier (26B"), the power conditioning unit (430) configured to adjust at least one of a current and a voltage from the power source (420) to improve efficiency of power transfer.

[0281] In another embodiment, as described in relation to Figures 19A, 19B, 27A and 27B, and 28A and 28B, the electrically powered system comprises a mechanical load supporting structure (510, 630) having a first portion that is electrically conductive, a power load, and a power transmission system (10", 410) comprising at least one radio frequency resonator (30", 50") configured for near-field wireless power transmission, the resonator having a first portion that is at least partially electrically conductive. The electrically powered system may further comprise a rechargeable battery (520), and the power load may comprise an electric motor (530). The electrically powered system may be an electric vehicle (500, 500'), and the mechanical load supporting structure may comprise a chassis (510) of the electric vehicle. The electrically powered system may be a display monitor (610), and the mechanical load supporting structure may be at least one of a frame (630) and a base of the display monitor.

[0282] The electrical power system may further include a power source. The power transfer system includes a radio frequency power amplifier (26B") in wired electrical communication with a power source and configured to convert a DC voltage from the power source to an AC voltage signal having an oscillating frequency, an adjustable phase radio frequency rectifier (46D) in wired electrical contact with a power load (70") and in radio frequency communication with the power amplifier (26B"), the rectifier (46D) configured to receive the transmitted power from the power amplifier (26B"), and a receiver controller (42") in communication with the rectifier (46D), the receiver controller (42") configured to adjust an efficiency of power transfer from the power amplifier (26B") to the rectifier (46D) by adjusting a current-voltage phase characteristic of the rectifier (46D).

[0283] In another embodiment, as depicted in Figures 19A and 19B, 27A and 27B, and 28A and 28B, an apparatus comprises a mechanical load supporting structure (510, 630) having a first portion that is electrically conductive, a power source, a power load (70", 530, 610), and a power transmission system (10", 410) in wired electrical communication with the power source and configured to convert a direct current voltage from the power source into an alternating current voltage signal having an oscillating frequency, a radio frequency power amplifier (26B") in wired electrical contact with the power load (70") and wirelessly connected to the power amplifier (26B") a receiver controller (42") in communication with the rectifier (46D), the receiver controller (42") configured to adjust an efficiency of power transfer from the power amplifier (26B") to the rectifier (46D) by adjusting a current-voltage phase characteristic of the rectifier (46D), wherein a conductive first portion is arranged to convey a radio frequency signal at least one from the power amplifier (26B") and to the rectifier (46D).

[0284] The apparatus may further comprise a power signal load management system (46E") in wired communication with the power load (70") and disposed in a power signal direction between the power load (70") and the rectifier (46D), the load management system (46E") configured to increase efficiency of power transfer by adjusting an input impedance of the rectifier (46D). The apparatus may further comprise a transmitter controller (22") in communication with the power amplifier (26B"), the transmitter controller (22") configured to increase efficiency of power transfer by adjusting a current-voltage phase characteristic of the power amplifier (26B"). The apparatus may further comprise an oscillator (26A") in communication with the power amplifier (26B") and the transmitter controller (22"), the transmitter controller (22") configured to adjust the oscillation frequency via the oscillator (26A").

[0285] The power amplifier (26B") may be in direct wired radio frequency communication with a rectifier (46D) via a first portion that is conductive. The power amplifier (26B") may be in wireless near-field radio frequency communication with the rectifier (46D). The power transfer system (10", 410) may include a transmitter resonator (30") in wired radio frequency communication with the power amplifier (26B") and a receiver resonator (50") in wired radio frequency communication with the rectifier (46D), one of the transmitter resonator (30") and the receiver resonator (50") may include the first portion that is conductive. The transmitter resonator (30") and the receiver resonator (50") may be in wireless near-field radio frequency communication with each other. The power amplifier (26B") may be in communication with the rectifier (46D) via at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. The power amplifier (26B") may be in two-way near-field wireless radio frequency communication with the rectifier (46D). The DC power source may comprise a rechargeable battery (520) and the power load may comprise an electric motor (530).

[0286] Currently Preferred Embodiment 1. In one currently preferred embodiment, the present invention provides a dual-mode near-field resonant wireless power transfer system configured to simultaneously transmit capacitive power and inductive power according to an adjustable transmission mode ratio between capacitive power transmission and inductive power transmission at a variable resonant power signal oscillation frequency, the system comprising: a transmitter subsystem comprising a transmitter antenna subsystem and a power signal tuner module, the power signal tuner module configured to adjust the transmission mode ratio by adjusting a power signal provided to the transmitter antenna subsystem by the power signal tuner module; and a receiver subsystem comprising a receiver antenna subsystem configured to receive power from the transmitter antenna at the transmission mode ratio. 2. The two-way near-field resonant wireless power transfer system described in paragraph 1, wherein the power signal tuner module is configured to adjust the power signal by adjusting the phase difference between the current and voltage of the power signal provided to the transmitter antenna subsystem. 3. The dual-mode near-field resonant wireless power transfer system described in paragraph 2, wherein the transmitter subsystem further comprises a controller and at least one sensor, the controller configured to receive sensor information from the at least one sensor and automatically provide tuning instructions to the power signal tuner module based on the sensor information, and the tuner module configured to adjust the phase difference between the current and voltage of the power signal provided to the transmitter antenna subsystem in accordance with the tuning instructions. 4. The dual-mode near-field resonant wireless power transfer system described in paragraph 3, wherein the at least one sensor is located on the transmitter subsystem. 5. The dual-mode near-field resonant wireless power transfer system described in paragraph 3, wherein the at least one sensor is disposed on the receiver subsystem and the controller is configured to wirelessly receive the sensor information. 6. A dual-mode near-field resonant wireless power transfer system as described in any one of paragraphs 3-5, wherein the at least one sensor comprises a power load sensor. 7. A dual-mode near-field resonant wireless power transfer system as described in any one of paragraphs 3-6, wherein the at least one sensor comprises a transmission power sensor. 8. A two-way near-field resonant wireless power transfer system as described in any one of paragraphs 3-7, wherein the at least one sensor comprises an ambient object detector. 9. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 3-8, wherein the at least one sensor includes a distance detector that detects the distance between the transmitter antenna subsystem and the receiver antenna subsystem. 10. A two-way near-field resonant wireless power transmission system described in any one of paragraphs 1-9, wherein the variable resonant power signal oscillation frequency is freely variable within a predetermined frequency band. 11. A dual-mode near-field resonant wireless power transfer system as described in paragraph 10, wherein the predetermined frequency band is between 1 MHz and 1 GHz. 12. A dual mode near field resonant wireless power transfer system as described in paragraph 10, wherein the system is detuned to an extent that enables the variable resonant power signal oscillation frequency to vary within opposing limits within the predetermined frequency band. 13. In one currently preferred embodiment, the present invention provides a wireless power transfer system comprising: a primary side comprising a transmitter module and a transmitter resonator, the transmitter module configured to adjust a transmission mode ratio between capacitive and inductive power transfer by adjusting current and voltage values ​​to the transmitter resonator, thereby generating oscillating magnetic and electric fields from the transmitter resonator; and a secondary side comprising a receiver module and a receiver resonator, the receiver resonator configured to generate a current when placed within the oscillating electric and magnetic fields generated by the transmitter resonator, the receiver module transmitting the current from the transmitter resonator to a load. 14. The dual-mode near-field resonant wireless power transfer system described in paragraph 13, wherein the transmitter resonator and the receiver resonator are equipped with at least one antenna. 15. The dual-mode near-field resonant wireless power transfer system described in paragraph 14, wherein the at least one antenna is coil-shaped. 16. The dual mode near field resonant wireless power transfer system of paragraph 14, wherein the at least one antenna is zigzag shaped. 17. The dual mode near field resonant wireless power transfer system of paragraphs 15 or 16, wherein the at least one antenna further comprises an angular corner portion. 18. The dual-mode near-field resonant wireless power transfer system described in paragraph 14, wherein the at least one antenna is circular. 19. The dual-mode near-field resonant wireless power transfer system of any one of paragraphs 3 to 5, wherein the at least one antenna is substantially flat. 20. A dual-mode near-field resonant wireless power transfer system according to any one of paragraphs 14-19, comprising at least two antennas. 21. A dual-mode near-field resonant wireless power transfer system as described in paragraph 20, wherein the at least two antennas are separated by a spacer. 22. The dual-mode near-field resonant wireless power transfer system described in paragraph 21, wherein the spacer comprises air, a dielectric material, ferrite, or a combination thereof. 23. In one currently preferred embodiment, the present invention provides a wireless power transfer system comprising a transmit subsystem comprising one or more transmitter resonators and one or more transmitter modules for controlling power signal output to the one or more transmitter resonators, each transmitter module comprising a controller, the one or more transmitter modules in electrical communication with the one or more transmitter resonators. 24. A dual-mode near-field resonant wireless power transfer system as described in paragraph 60, wherein each transmitter resonator of the one or more transmitter resonators is coupled to one transmitter module of the one or more transmitter modules to form one or more transmitter pairs. 25. A dual-mode near-field resonant wireless power transfer system as described in paragraph 61, wherein the one or more transmitter pairs are electrically isolated from each other. 26. A dual-mode near-field resonant wireless power transfer system as described in paragraph 62, wherein the one or more transmitter pairs are electrically isolated from each other by a grounded shielding grid such that there is no electrical communication between the one or more transmitter pairs. 27. A dual-mode near-field resonant wireless power transfer system as described in any one of paragraphs 60-63, wherein the transmit controller of each transmitter module is equipped with a load detector for measuring the input impedance of the associated transmitter resonator. 28. A dual-mode near-field resonant wireless power transfer system as described in paragraph 64, wherein the transmit controller varies the frequency of the power signal based on the measured input impedance of the connected transmitter. 29. A dual-mode near-field resonant wireless power transfer system as described in paragraph 65, wherein each transmit controller of the one or more transmit modules is provided with a tuner module for varying the phase of the output of the power signal. 30. A dual-mode near-field resonant wireless power transfer system according to any one of paragraphs 60-66, wherein the one or more transmitter resonators are configured to form a transmission surface. 31. The dual-mode near-field resonant wireless power transfer system of any one of paragraphs 60-67, further comprising one or more receiver subsystems, each comprising one or more receiver resonators. 32. A dual-mode near-field resonant wireless power transfer system as described in paragraph 68, wherein the transmit controller of each transmitter module includes a load detector for measuring an input impedance of one or more connected transmitter resonators, the load detector detecting a change in the input impedance when the one or more receiver resonators come into proximity to the one or more connected transmitter resonators. 33. A dual-mode near-field resonant wireless power transfer system as described in paragraph 69, wherein the transmit controller varies the frequency of the power signal based on a measured input impedance of a connected transmitter. 34. The dual-mode near-field resonant wireless power transfer system described in paragraph 70, wherein the controller includes a tuner module for varying the phase of the power signal. 35. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 68-71, wherein power is transmitted from one or more transmitter resonators of the transmit subsystem to one or more receiver resonators of the one or more receiver subsystems at a resonant frequency. 36. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 68-72, wherein power is transmitted from one or more transmitter resonators of the transmit subsystem to one or more receiver resonators of the one or more receiver subsystems by near-field magnetic induction. 37. A two-way near-field resonant wireless power transfer system described in any one of paragraphs 68-73, wherein power is transferred from one or more transmitter resonators of the transmit subsystem to one or more receiver resonators of the one or more receiver subsystems by near-field capacitance. 38. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 69-74, wherein the load detector of the transmitting controller of each transmitting module measures the input impedance of one connected transmitter resonator. 39. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 69-74, wherein a load detector of a transmitting controller of each transmitting module measures the input impedance of two connected transmitter resonators. 40. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 69-74, wherein a load detector of a transmitting controller of each transmitting module measures the input impedance of three connected transmitter resonators. 41. A dual-mode near-field resonant wireless power transfer system described in any one of paragraphs 69-74, wherein the load detector of the transmitting controller of each transmitting module measures the input impedance of four or more connected transmitter resonators. 42. In one currently preferred embodiment, the present invention provides a method of varying a power signal in a wireless transmission system, the method comprising the steps of providing a transmit surface comprised of one or more transmitter resonators, monitoring an input impedance of each transmitter resonator of the one or more transmitter resonators, and controlling a power signal output to each transmitter resonator of the one or more transmitter resonators based on the input impedance. 43. The method of paragraph 79, further comprising the step of calibrating a baseline impedance for the one or more transmitter resonators. 44. The method of paragraph 80, further comprising either a step of assigning an off state to one transmitter resonator of the one or more transmitter resonators when the input impedance is less than a baseline impedance, or a step of assigning a powered state to the one transmitter resonator when the input impedance exceeds a baseline impedance. 45. The method of paragraph 81, further comprising setting a frequency of the power signal output to the one or more transmitter resonators assigned to the wake-up state. 46. ​​The method of paragraph 82, further comprising adjusting a phase of a power output signal of the one or more transmitter resonators assigned to the wake-up state to a maximum power transfer phase, at which time power transfer through the transmitter resonators is substantially maximum. 47. The method of any one of paragraphs 79-83, further comprising providing one or more receiver resonators proximate the transmitting surface. 48. In one currently preferred embodiment, the present invention provides a near field resonant wireless power transfer system comprising: a transmit subsystem comprising a plurality of substantially mutually isolated transmitter resonators, and a corresponding transmitter module in power signal communication with each transmitter resonator, each transmitter module including a transmit controller and a power signal source having a power signal oscillation frequency and a power signal phase, each power signal source being controlled by said corresponding transmit controller; one or more receiver subsystems, each comprising a corresponding receiver resonator; a software lookup table of individual power signal oscillation frequencies enabled for said power signal sources; and software loaded into memory and which, when executed by a controller of any of said transmitter modules, performs the actions of: transmitting one of an input impedance of the corresponding transmitter resonator and a test signal power consumption by the corresponding transmitter resonator; and selecting a frequency from the lookup table for the corresponding power signal source based on one of the input impedance of the corresponding transmitter resonator and the test signal power consumption by the corresponding transmitter resonator. 49. A near field resonant wireless power transfer system as described in paragraph 85, wherein when executed, the software performs the action of adjusting the phase of a power signal from the corresponding power signal source while measuring the power value transmitted by the corresponding transmitter resonator. 50. A near-field resonant wireless power transfer system as described in paragraph 85 or 86, wherein the transmitter resonators are substantially separated from each other by a grounded shielding grid. 51. In one currently preferred embodiment, the present invention provides a near-field wireless system for transmitting power from one or more photovoltaic cells to a power load, the near-field wireless system comprising: one or more transmitter modules in electrical communication with one or more photovoltaic cells, each transmitter module configured to convert power from one of the one or more photovoltaic cells into an oscillating power signal having an oscillating frequency; one or more transmitter resonators in electrical communication with the one or more transmitter modules, each transmitter resonator configured to resonate at the oscillating frequency; one or more receiver resonators, each configured to resonate at the oscillation frequency and positioned to receive power from the one or more transmitter resonators via at least one of capacitive coupling and magnetic induction; and one or more receiver modules in electrical communication with the receiver resonators, each receiver module configured to receive power from at least one of the one or more receiver resonators, convert the power received from the receiver resonators into a DC voltage, and transmit the DC voltage to the power load. 52. The near field wireless system described in paragraph 1, wherein the one or more transmitting modules each include a power amplifier configured to condition the power received from the one or more photovoltaic cells at the oscillation frequency. 53. The near field wireless system described in paragraph 24, wherein the one or more transmitting modules each include an oscillator configured to provide the oscillation frequency to the power amplifier. 54. A near field wireless system described in any one of paragraphs 1-25, wherein each of the one or more transmitting modules comprises a controller and one or more sensors, and the controller is configured to vary the vibration frequency based on first information obtained from at least one of the one or more sensors. 55. The near field wireless system described in paragraph 26, wherein each of the one or more transmitting modules is configured, under control of the controller, to modify at least one phase of power provided by the transmitting module to the one or more transmitter resonators based on second information obtained from at least one of the one or more sensors. 56. A near field wireless system described in any one of paragraphs 1-27, comprising one or more power conditioning units electrically connected between the one or more photovoltaic cells and the one or more transmitting modules, each power conditioning unit configured to adapt power from at least one of the one or more photovoltaic cells into a format compatible with the one or more transmitting modules. 57. A near field wireless system as described in paragraph 28, wherein each transmitting module of the one or more transmitting modules comprises a small signal electronic circuit, and the power conditioning unit is further configured to provide power to the small signal electronic circuit. 58. A near field wireless system described in any one of paragraphs 1-29, wherein the one or more transmitter resonators are positioned on a surface of at least one of the one or more photovoltaic cells opposite a dynamic solar radiation receiving surface of at least one of the one or more photovoltaic cells. 59. The near field wireless system described in paragraph 30, wherein the one or more transmitter resonators have a surface area that is at least a major fraction of a dynamic solar radiation receiving surface of at least one of the one or more photovoltaic cells. 60. A near field wireless system described in any one of paragraphs 1-31, wherein each transmitter resonator has a first planar area and each receiver resonator has a second planar area, the second planar area being larger than the first planar area. 61. A near field wireless system described in any one of paragraphs 1-32, wherein each receiver resonator of the one or more receiver resonators is arranged and configured to receive power from more than one of the one or more transmitter resonators via at least one of capacitive coupling and magnetic induction at the resonant frequency. 62. A near field wireless system described in any one of paragraphs 1-33, wherein the one or more transmitting modules are in electrical communication with the one or more photovoltaic cells via a wired connection. 63. A near field wireless system described in any one of paragraphs 1-34, wherein the one or more transmitting modules are in electrical communication with the one or more transmitter resonators via a wired connection. 64. A near field wireless system described in any one of paragraphs 1-35, wherein the one or more receiver modules are in electrical communication with the one or more receiver resonators via a wired connection. 65. In one currently preferred embodiment, the invention provides a method of transmitting power from a photovoltaic cell to a power load, the method comprising: converting power from the photovoltaic cell into an oscillating power signal having an oscillating frequency in a transmitter module; transmitting the power to a transmitter resonator in wired electrical communication with the transmitter module and configured to resonate at the oscillating frequency; receiving power from the transmitter resonator via at least one of capacitive coupling and magnetic induction into a receiver resonator, the receiver resonator configured to resonate at the oscillating frequency; receiving power from the receiver resonator into a receiver module in wired electrical communication with the receiver resonator; forming the power into a direct current form; and transmitting the power via wired electrical communication to the power load. 66. The method of paragraph 37, further comprising converting the voltage and current of the power from the photovoltaic cell to a voltage and current adapted to the transmission module before converting the power into an oscillating power signal. 67. A method of transmitting power from an array of photovoltaic cells to a power load, comprising: converting, in each transmitter module of a plurality of corresponding transmitter modules, power from each photovoltaic cell of a plurality of photovoltaic cells in the array of photovoltaic cells into an oscillating power signal having an oscillating frequency; transmitting the power in each transmitter module of the transmitter modules to a corresponding transmitter resonator of a plurality of transmitter resonators, each transmitter resonator configured to resonate at the oscillating frequency; receiving power from the plurality of transmitter resonators in a receiver resonator via at least one of capacitive coupling and magnetic induction, the receiver resonator configured to resonate at the oscillating frequency; receiving the power in a receiver module in wired electrical communication with the receiver resonator; forming the power into a direct current form; and transmitting the power via wired electrical communication to the power load. 68. The method of paragraph 39, further comprising converting the voltage and current of the power from each photovoltaic cell to a voltage and current adapted to a corresponding transmission module prior to converting the power into an oscillating power signal. 69. In one currently preferred embodiment, the invention provides a method for transmitting power from an array of photovoltaic cells to a power load, the method comprising: converting, in each transmitter module of a first plurality of corresponding transmitter modules, power from each photovoltaic cell in the array into an oscillating power signal having an oscillating frequency; transmitting power from each transmitter module of the transmitter modules to a corresponding transmitter resonator of a second plurality of transmitter resonators, each transmitter resonator configured to resonate at the oscillating frequency; receiving power from each transmitter resonator in a corresponding receiver resonator configured to resonate at the oscillating frequency, each receiver resonator further configured and arranged to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction; receiving power from each receiver resonator in a corresponding receiver module in wired electrical communication with the receiver resonator; and forming the received power in direct current form via wired electrical communication with the electrical load. 70. The method of paragraph 41, further comprising converting the voltage and current of the power from each photovoltaic cell to a voltage and current adapted to a corresponding transmission module before converting the power into an oscillating power signal. 71. In one currently preferred embodiment, the invention provides a method for transmitting power from an array of photovoltaic cells to a power load, the method comprising the steps of: converting, in each transmitter module of a plurality of corresponding transmitter modules, power from each photovoltaic cell in the array of photovoltaic cells into an oscillating power signal having an oscillating frequency; transmitting power from each transmitter module of the transmitter module to one transmitter resonator of a plurality of transmitter resonators, each transmitter resonator configured to resonate at the oscillating frequency; receiving power from each transmitter resonator in any adjacent receiver resonator of a plurality of receiver resonators configured to resonate at the oscillating frequency, each receiver resonator further configured and arranged to receive power from the transmitter resonator via at least one of capacitive coupling and magnetic induction; sharing the received power among the plurality of receiver resonators; rendering the received power in one or more receiver resonators of the plurality of receiver resonators in a direct current form; and transmitting the power in direct current form to the power load via wired electrical communication. 72. The method of paragraph 43, further comprising converting the voltage and current of the power from each photovoltaic cell to a voltage and current adapted to a corresponding transmission module before converting the power into an oscillating power signal. 73. A photovoltaic power collection system for transmitting power from a plurality of photovoltaic cells to a power load, comprising: one or more power conditioning units in electrical communication with one or more photovoltaic cells of the plurality of photovoltaic cells; and at least one receiver module in electrical communication with the one or more power conditioning units, each power conditioning unit configured to adapt power from the one or more photovoltaic cells to a format compatible with the receiver module, the receiver module configured to adapt power from the power conditioning units to a format compatible with the power load. 74. A photovoltaic power collection system as described in paragraph 45, wherein one power conditioning unit is provided for each photovoltaic cell. 75. The photovoltaic power collection system of paragraph 45 or 46, wherein the one or more power conditioning units are in electrical communication with the one or more photovoltaic cells via a wired connection. 76. A photovoltaic power collection system as described in any one of paragraphs 45-47, wherein the at least one receiver module is in electrical communication with the one or more power conditioning units via a wired connection. 77. A photovoltaic power collection system as described in any one of paragraphs 45-48, wherein the at least one receiver module is in electrical communication with the one power load via a wired connection. 78. A photovoltaic power collection system as described in any one of paragraphs 45-49, further comprising one or more power amplifiers in electrical communication with the one or more power conditioning units and the at least one receiver module. 79. The photovoltaic power collection system described in paragraph 50, wherein the one or more power amplifiers are in electrical communication with the one or more power conditioning units via a wired connection, and the one or more power amplifiers are in electrical communication with the at least one receiver module via a wired connection. 80. The photovoltaic power collection system of paragraphs 50 or 51, wherein the power amplifier converts DC power received from the one or more power conditioning units into AC power. 81. The photovoltaic power collection system described in paragraph 52, wherein the power amplifier transmits the AC power to the at least one receiver module. 82. In one currently preferred embodiment, the present invention provides a method for transmitting power from a plurality of photovoltaic cells to a power load, the method including the steps of transmitting power from the plurality of photovoltaic cells to one or more power conditioning units, conditioning the power into a format compatible with the power load, and transmitting the power to the power load. 83. The method of paragraph 54, wherein the step of putting the power into a format compatible with the power load includes converting the power to direct current power. 84. The method of paragraph 54, wherein the step of putting the power into a format compatible with the power load includes converting the power to AC power. 85. The method of any one of paragraphs 54-56, comprising: converting the power into a format compatible with one or more receiver modules; and transmitting the power to the one or more receiver modules prior to converting the power into a format compatible with the power load. 86. The method of paragraph 57, wherein the step of putting the power into a format compatible with the one or more receiver modules includes converting the power to AC power. 87. The method of paragraph 57, wherein the step of putting the power into a format compatible with the one or more receiver modules includes converting the power to DC power. 88. In one currently preferred embodiment, the invention provides a method for transmitting power from a DC power source to a power load, the method comprising: providing a power transmission system in wired electrical communication with the power source, the power transmission system comprising an oscillator capable of oscillating at an oscillating frequency, a power amplifier and a transmitter tuning network under control of a transmitter controller, and a receiver tuning network and a load management system under control of a receiver controller, the load management system being in wired electrical communication with the power load; converting power from the power source in the power amplifier into an oscillating power signal having an oscillating frequency; transmitting the power signal from the power amplifier to the load management system via the transmitter tuning network and the receiver tuning network under control of the transmitter controller; adjusting at least one of the oscillating frequency, an input DC equivalent resistance of the power amplifier, the transmitter tuning network, the receiver tuning network, and the load management system to change a power transfer rate; and placing the power load received by the load management system in a DC form via wired electrical communication. 89. The method of paragraph 88, wherein transmitting the power signal through the transmitter tuning network and the receiver tuning network includes transmitting power via wired communication. 90. The method of paragraph 88, wherein transmitting the power signal through the transmitter tuning network and the receiver tuning network includes transmitting power by wireless communication. 91. The method of paragraph 90, wherein transmitting power by wireless communication includes transmitting power by near-field wireless communication. 92. The method of paragraph 91, wherein transmitting power by near-field wireless communication includes transmitting power by at least one of capacitive coupling and inductive coupling. 93. The method of any one of paragraphs 88-92, wherein transmitting power from a DC power source includes transmitting power from at least one solar cell. 94. The method of any one of paragraphs 88-93, wherein transmitting power from the DC power source includes transmitting power from at least one battery. 95. The method of any one of paragraphs 88-94, wherein transmitting power from a DC power source includes transmitting power from a power source with a fluctuating voltage. 96. In one currently preferred embodiment, the invention provides a method for power transmission from a DC power source to a power load, the method including the steps of providing a power transmission system in wired electrical communication with the power source, the power transmission system comprising a radio frequency power amplifier in radio frequency communication with an adjustable phase radio frequency rectifier in wired electrical contact with the power load; converting power from the DC power source to a radio frequency oscillating power signal in the power amplifier; converting the radio frequency oscillating power signal to a DC power signal in the rectifier; and adjusting efficiency of the power transfer by adjusting current-voltage phase characteristics of the rectifier. 97. The method of paragraph 96, wherein providing the adjustable phase radio frequency rectifier includes providing a differential self-synchronous radio frequency rectifier. 98. The method of paragraph 96 or 97, further comprising adjusting the efficiency of power transfer by adjusting the DC equivalent input resistance of the power amplifier. 99. The method of paragraph 97, wherein the step of providing a power transmission system includes providing a load management system in wired communication with the rectifier and the power load. 100. The method of paragraph 99, wherein adjusting the DC equivalent input resistance of the power amplifier includes adjusting an input impedance of the rectifier by adjusting the load management system. 101. The method of paragraph 100, wherein adjusting the load management system includes automatically adjusting the load management system. 102. The method of paragraph 96, further comprising adjusting efficiency of power transfer by adjusting current-voltage phase characteristics of the power amplifier. 103. The method of paragraph 102, wherein the step of providing a power transmission system includes providing a transmitter controller in communication with the power amplifier for controlling the power amplifier. 104. The method of paragraph 103, wherein the adjustment of the current-voltage phase characteristics of the power amplifier is performed by the transmitter controller. 105. The method of paragraph 104, wherein the adjustment of the current-voltage phase characteristics of the power amplifier is performed automatically by the transmitter controller. 106. The method of paragraph 96, further comprising adjusting the efficiency of power transfer by changing the oscillation frequency of the power amplifier. 107. The method of paragraph 96, wherein the step of providing a power transfer system includes providing a receiver controller in communication with the rectifier for controlling the rectifier. 108. The method of paragraph 107, wherein the adjustment of the current-voltage phase characteristics of the rectifier is performed by the receiver controller. 109. The method of paragraph 108, wherein the adjustment of the rectifier current-voltage phase characteristics is performed automatically by the receiver controller. 110. The method of paragraph 96, wherein the step of providing a power transfer system includes providing a power amplifier in direct wired radio frequency communication with the adjustable phase radio frequency rectifier. 111. The method of paragraph 96, wherein the step of providing a power transmission system includes the step of providing a power amplifier in wireless near-field radio frequency communication with the adjustable phase radio frequency rectifier. 112. The method of paragraph 96, wherein the step of providing the power transmission system includes the step of providing a transmitter resonator in wired radio frequency communication with the power amplifier, and a receiver resonator in wired radio frequency communication with the radio frequency rectifier. 113. The method of paragraph 112, further comprising operating the transmitter resonator and the receiver resonator in wireless near-field radio frequency communication with each other. 114. The method of paragraph 96, wherein the step of providing a power transmission system includes providing a power amplifier in communication with the rectifier for at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. 115. The method of paragraph 96, wherein the step of providing a power transfer system includes providing a power amplifier in dual-mode near-field wireless communication with the rectifier. 116. The method of paragraph 96, further comprising: providing a power conditioning unit electrically disposed between the power source and the power amplifier; and adjusting the power conditioning unit to adjust at least one of a current and a voltage from the power source to improve efficiency of power transfer. 117. In one currently preferred embodiment, a power transmission system for supplying power from a DC power source to a power load, the power transmission system comprising: a radio frequency power amplifier in wired electrical communication with the power source and configured to convert a DC voltage from the power source to an AC voltage signal having an oscillating frequency; an adjustable phase radio frequency rectifier in wired electrical contact with a power load and in radio frequency communication with the power amplifier; the rectifier configured to receive transmitted power from the power amplifier; and a receiver controller in communication with the rectifier, the receiver controller configured to adjust an efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier. 118. The power transfer system described in paragraph 117, wherein the receiver controller is configured to automatically adjust the current-voltage phase characteristics of the rectifier. 119. The power transmission system described in paragraph 117, further comprising a load management system in wired communication with the power load, and a power signal disposed between the power load and the rectifier, the load management system configured to increase efficiency of power transmission by adjusting an input impedance of the rectifier. 120. The power transmission system of paragraph 119, wherein the load management system is configured to automatically adjust the input impedance of the rectifier. 121. The power transfer system described in paragraph 117, further comprising a transmitter controller in communication with the power amplifier, the transmitter controller configured to increase efficiency of power transfer by adjusting current-voltage phase characteristics of the power amplifier. 122. The power transfer system of paragraph 121, wherein the transmitter controller is configured to automatically adjust the current-voltage phase characteristics of the power amplifier to increase efficiency of power transfer. 123. The power transfer system of paragraph 117, further comprising an oscillator in communication with the power amplifier and the transmitter controller, the transmitter controller configured to adjust the oscillation frequency via the oscillator. 124. The power transfer system described in paragraph 117, wherein the power amplifier is in direct wired radio frequency communication with the rectifier. 125. The power transfer system described in paragraph 117, wherein the power amplifier is in wireless near-field radio frequency communication with the rectifier. 126. The power transmission system described in paragraph 117, wherein the power transmission system includes a transmitter resonator in wired radio frequency communication with the power amplifier, and a receiver resonator in wired radio frequency communication with the rectifier. 127. The power transfer system described in paragraph 126, wherein the transmitter resonator and the receiver resonator are in wireless near-field radio frequency communication with each other. 128. The power transfer system described in paragraph 117, wherein the power amplifier is in communication with the rectifier via at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. 129. The power transfer system described in paragraph 117, wherein the power amplifier is in two-way near-field wireless radio frequency communication with the rectifier. 130. The power transfer system of paragraph 117, wherein the DC power source comprises a rechargeable battery and the power load comprises an electric motor. 131. The power transmission system of paragraph 117, wherein the power load is equipped with a display monitor. 132. A power transmission system as described in paragraph 117, wherein the resonant structure of the system comprises at least one conductive mechanical load bearing against a structural element of the system. 133. The power transfer system described in paragraph 117, further comprising a power conditioning unit electrically disposed between the power source and the power amplifier, the power conditioning unit configured to adjust at least one of the current and voltage from the power source to improve efficiency of power transfer. 134. In one currently preferred embodiment, the invention provides an electrically powered system comprising: a mechanical load supporting structure having a first portion that is electrically conductive; a power load; and a power transmission system comprising at least one radio frequency resonator configured for near field wireless power transmission, the resonator having a first portion that is at least partially electrically conductive. 135. The power system of paragraph 134, wherein the power system further comprises a rechargeable battery and the power load comprises an electric motor. 136. The electric power system described in paragraph 135, wherein the electric power system is an electric vehicle and the mechanical load supporting structure comprises a chassis of the electric vehicle. 137. The powered system described in paragraph 134, wherein the powered system is a display monitor and the mechanical load supporting structure is at least one of a frame and a base of the display monitor. 138. The electrically powered system described in paragraph 134, further comprising a power source. 139. The electrically powered system described in paragraph 138, wherein the power transmission system comprises: a radio frequency power amplifier in wired electrical communication with the power source and configured to convert a direct current voltage from the power source into an alternating current voltage signal having an oscillating frequency; an adjustable phase radio frequency rectifier in wired electrical contact with a power load and in radio frequency communication with the power amplifier; a rectifier configured to receive the transmitted power from the power amplifier; and a receiver controller in communication with the rectifier, the receiver controller configured to adjust the efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier. 140. In one currently preferred embodiment, the invention provides an apparatus comprising: a mechanical load supporting structure having a conductive first portion; a power source; a power load; and a power transmission system comprising: a radio frequency power amplifier in wired electrical communication with the power source and configured to convert a direct current voltage from the power source to an alternating current voltage signal having an oscillating frequency; a tunable phase radio frequency rectifier in wired electrical contact with the power load and in radio frequency communication with the power amplifier; the rectifier configured to receive power transmitted from the power amplifier; and a receiver controller in communication with the rectifier, the receiver controller configured to adjust efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier; 141. The apparatus described in paragraph 140, further comprising a load management system in wired communication with the power load and a power signal disposed between the power load and the rectifier, the load management system configured to increase efficiency of power transfer by adjusting an input impedance of the rectifier. 142. The apparatus described in paragraph 140, further comprising a transmitter controller in communication with the power amplifier, the transmitter controller configured to increase efficiency of power transfer by adjusting current-voltage phase characteristics of the power amplifier. 143. The apparatus described in paragraph 140, further comprising an oscillator in communication with the power amplifier and the transmitter controller, the transmitter controller configured to adjust the oscillation frequency with the oscillator. 144. The apparatus described in paragraph 140, wherein the power amplifier is in direct wired radio frequency communication with the rectifier via a first portion that is conductive. 145. The apparatus described in paragraph 140, wherein the power amplifier is in wireless near-field radio frequency communication with the rectifier. 146. The apparatus described in paragraph 140, wherein the power transmission system includes a transmitter resonator in wired radio frequency communication with the power amplifier and a receiver resonator in wired radio frequency communication with the rectifier, wherein one of the transmitter resonator and the receiver resonator includes the first portion that is conductive. 147. The apparatus described in paragraph 146, wherein the transmitter resonator and the receiver resonator are in wireless near-field radio frequency communication with each other. 148. The apparatus of paragraph 140, wherein the power amplifier is in communication with the rectifier via at least one of capacitive near-field wireless radio frequency communication and inductive near-field wireless radio frequency communication. 149. The apparatus described in paragraph 140, wherein the power amplifier is in two-way near-field wireless radio frequency communication with the rectifier. 150. The apparatus of paragraph 140, wherein the DC power source comprises a rechargeable battery and the power load comprises an electric motor.

[0287] While a number of exemplary aspects and embodiments have been described above, those of ordinary skill in the art will recognize certain modifications, permutations, additions, and subcombinations thereof. Accordingly, it is intended that the following appended claims and the claims set forth hereinafter be interpreted to include all such modifications, permutations, additions, and subcombinations as would be consistent with the broadest interpretation of the entire specification. Interpretation of Terms

[0288] The following terminology is used throughout the specification and claims, unless the context clearly requires otherwise.

[0289] The words "comprise", "comprising" and the like are to be construed in their inclusive sense as opposed to their exclusive or exhaustive sense, i.e. "including, but not limited to".

[0290] "Coupled" or any variation thereof means any direct or indirect connection or coupling between two or more elements, where the coupling or connection between the elements may be physical, logical, or a combination thereof, and elements that are formed integrally may be considered to be connected or coupled.

[0291] "Wired," "via a wired connection," or variations thereof, mean any physical connection via a conductive medium, intermediate circuit, or other means that allows electrical current to flow between, through, or across components of a system.

[0292] "Electric communication," "electrical communication," or variations thereof, means any communication, coupling, interface, or other means, whether hardwired, wireless, or a combination thereof, suitable for the transmission of electrical signals between or across components of a system.

[0293] The words "herein," "above," "below," and words of similar import, when used to describe this specification, shall refer to this specification as a whole and not to particular portions of the specification.

[0294] When "or" refers to a list of two or more items, it includes the following interpretations of the word: any of the items in the list, all of the items in the list, and all of any combination of the items in the list.

[0295] The singular forms "a," "an," and "the" include any appropriate plural references.

[0296] Directional words such as "vertical," "side," "horizontal," "upper," "lower," "forward," "rearward," "inward," "outward," "vertical," "side," "left," "right," "front," "rear," "top," "bottom," "up," "down," and the like, as used in this specification and any accompanying claims (if any), are dependent upon the particular orientation of the device as described and illustrated. The subject matter described herein can assume various alternative orientations. Thus, these directional terms are not precisely defined and should not be interpreted narrowly.

[0297] Embodiments of the present invention include various operations described herein, which may be performed by hardware components, software, firmware, or any combination thereof.

[0298] Certain embodiments may be implemented as a computer program product that may include instructions stored on a machine-readable medium. These instructions may be used to program a general-purpose or special-purpose processor to perform the described operations. A machine-readable medium includes any mechanism for storing information in a form (e.g., software or processing application) readable by a machine (e.g., a computer). Machine-readable media include, but are not limited to, magnetic storage media (e.g., floppy disks); optical storage media (e.g., CD-ROM); magneto-optical storage media; read-only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM and EEPROM); flash memory; or other types of media suitable for storing electronic instructions.

[0299] In addition, some embodiments may be practiced in a distributed computing environment where the machine-readable medium is stored on and / or executed by more than one computer system. Additionally, information transmitted between computer systems may be transmitted in and out via a communications medium connecting the computer systems.

[0300] The computer processing components used to implement various embodiments of the present invention include one or more general-purpose processing devices, such as a microprocessor or central processing unit, a controller, a Graphical Processing Unit (GPU), a Cell Computer, etc. Alternatively, such digital processing components may include one or more special-purpose processing devices, such as a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), etc. In certain embodiments, for example, the digital processing device may be a network processor having multiple processors, including a core unit and multiple micro-engines. Furthermore, the digital processing device may include any combination of general-purpose and special-purpose processing devices.

[0301] Although the operations of the methods herein are shown and described in a particular order, the order of operations of each method may be changed such that certain operations are performed in the reverse order, or such that certain operations are performed at least in part concurrently with other operations. In alternative embodiments, instructions of different operations or sub-operations may be performed intermittently and / or interleaved.

[0302] When a component (e.g., a software module, processor, assembly, device, circuit, etc.) is referred to above, unless otherwise indicated, the reference to that component (including the reference to the "means") should be interpreted as including any component that performs the function of the described component (i.e., is functionally equivalent) as an equivalent of that component, including components that are not structurally equivalent to the disclosed structures that perform that function in the illustrated exemplary embodiments of the invention.

[0303] For purposes of explanation, specific examples of systems, methods, and devices have been described herein. These are merely examples. The techniques provided herein are applicable to systems other than the example systems described above. Many changes, modifications, additions, omissions, and permutations are possible within the scope of the practice of the invention. The invention includes variations of the described embodiments that will be apparent to those skilled in the art, including variations obtained by replacing features, elements, and / or acts with equivalent features, elements, and / or acts, mixing and matching features, elements, and / or acts from different embodiments, combining features, elements, and / or acts from the embodiments described herein with features, elements, and / or acts of other technologies, and / or omitting combinations of features, elements, and / or acts from the described embodiments.

Claims

1. 1. A method for transmitting power from a DC power source to a power load, comprising: providing a power transmission system in wired electrical communication with the power source, the power transmission system including a radio frequency power amplifier in radio frequency communication with an adjustable phase radio frequency rectifier in wired electrical contact with the power load; converting power from the DC power source in the power amplifier into a radio frequency oscillating power signal; converting the radio frequency oscillating power signal to a direct current power signal in the rectifier; adjusting the efficiency of power transfer by adjusting the current-voltage phase characteristics of the rectifier; The method includes:

2. The method of claim 1 , wherein the DC power source comprises at least one solar cell.

3. The method of claim 1 , further comprising the step of adjusting efficiency of power transfer by automatically adjusting a DC equivalent input resistance of the power amplifier.

4. The method of claim 1 , further comprising automatically adjusting efficiency of power transfer by automatically adjusting a current-voltage phase characteristic of the power amplifier.

5. The method of claim 1 , further comprising adjusting the efficiency of power transfer by varying an oscillation frequency of the power amplifier.

6. The method of claim 1 , wherein the step of providing a power transfer system includes providing a power amplifier in direct wired radio frequency communication with the adjustable phase radio frequency rectifier.

7. The method of claim 1 , wherein the step of providing a power transfer system includes providing a power amplifier in wireless near-field radio frequency communication with the adjustable phase radio frequency rectifier.

8. The method of claim 1 , wherein the step of providing a power transfer system includes providing a power amplifier in dual-mode near-field wireless communication with the rectifier.

9. A power transmission system for supplying power from a DC power source to a power load, comprising: a radio frequency power amplifier in wired electrical communication with the DC power source and configured to convert the DC voltage from the power source into an AC voltage signal having an oscillating frequency; an adjustable phase radio frequency rectifier in wired electrical contact with the power load and in radio frequency communication with the power amplifier, the rectifier configured to receive power transmitted from the power amplifier; a receiver controller in communication with the rectifier, the receiver controller configured to automatically adjust an efficiency of power transfer from the power amplifier to the rectifier by adjusting a current-voltage phase characteristic of the rectifier; A power transmission system comprising:

10. 10. The power transfer system of claim 9, further comprising a load management system in wired communication with the power load and disposed in a power signal direction between the power load and the rectifier, the load management system configured to automatically adjust an input impedance of the rectifier to increase efficiency of power transfer.

11. 10. The power transfer system of claim 9, further comprising a transmitter controller in communication with the power amplifier, the transmitter controller configured to increase efficiency of power transfer by automatically adjusting current-voltage phase characteristics of the power amplifier.

12. 10. The power transfer system of claim 9, further comprising an oscillator in communication with the power amplifier and the transmitter controller, the transmitter controller configured to adjust the oscillation frequency with the oscillator.

13. The power transfer system of claim 9 , wherein the power amplifier is in direct wired radio frequency communication with the rectifier.

14. 10. The power transfer system of claim 9, wherein the power amplifier is in wireless near-field radio frequency communication with the rectifier.

15. 10. The power transfer system of claim 9, wherein the power amplifier is in dual-mode near-field wireless radio frequency communication with the rectifier.

16. 10. The power transfer system of claim 9, wherein the DC power source comprises a rechargeable battery and the power load comprises an electric motor.

17. The power transfer system of claim 9 , wherein the resonant structure of the system comprises at least one electrically conductive mechanical load-supporting structural component of the system.

18. 10. The power transfer system of claim 9, further comprising a power conditioning unit electrically disposed between the power source and the power amplifier, the power conditioning unit configured to adjust at least one of a current and a voltage from the power source to improve efficiency of power transfer.

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