Wireless power transmission device with multiple primary coils and adjacent coil muting

Abstract

The present invention provides a system, device, apparatus, and method for a wireless power transmitter that supports charging of multiple wireless power receivers. [Solution] The wireless power transmission device includes a group of primary coils 121-123, 124-126, organized into zones. Each zone has a local controller for managing the operation of one primary coil within the zone at a time, and a master controller selectively couples primary coils to the local controller. When a first primary coil is coupled to a local controller in a zone, the other primary coils in that zone are disabled. The master controller manages which primary coils from adjacent zones are coupled to their respective local controllers and mutes or disables adjacent primary coils near the first primary coil.

Description

[Technical Field]

[0001] The present disclosure generally relates to wireless power, and more specifically relates to a wireless power transmission device. [Background Art]

[0002] Conventional wireless power systems have been developed primarily for the purpose of charging batteries in wireless power receiving devices such as mobile devices, small electronic devices, and gadgets. In a conventional wireless power system, a wireless power transmission device may include a primary coil that generates an electromagnetic field. The electromagnetic field can induce a voltage in a secondary coil of the wireless power receiving device when the secondary coil is placed in proximity to the primary coil. In this configuration, the electromagnetic field can wirelessly transmit power to the secondary coil. Power may be transmitted using resonant coupling or non-resonant inductive coupling between the primary coil and the secondary coil. The wireless power receiving device may operate using the received power, or may store the received energy in a battery for later use. Power transmission capability may be related to how close the primary coil and the secondary coil are arranged to each other. Therefore, in some conventional wireless power systems, the structure of the wireless power transmission device may be designed to restrict the positioning of the wireless power receiving device and impose an expected alignment between the primary coil and the secondary coil. [Summary of Invention]

[0003] The systems, methods, and devices of the present disclosure each have several innovative aspects, and no single one of them is solely responsible for the desirable attributes disclosed herein.

[0004] One innovative embodiment of the subject matter described herein can be implemented in a wireless power transmission device. In some implementations, the wireless power transmission device may include a plurality of primary coils organized into at least a first primary coil group and a second primary coil group. The wireless power transmission device may include at least a first local controller associated with the first primary coil group and a second local controller associated with the second primary coil group. A plurality of switches within the wireless power transmission device can individually couple the first local controller to one primary coil of the first primary coil group and the second local controller to one primary coil of the second primary coil group. The wireless power transmission device may include a master controller configured to operate a plurality of switches that control which primary coils of the first primary coil group are coupled to the first local controller and which primary coils of the second primary coil group are coupled to the second local controller.

[0005] In some implementations, the master controller may be configured to determine that a first primary coil among several primary coils is supplying wireless power to a first wireless power receiver. The master controller can operate several switches to keep one or more adjacent primary coils near the first primary coil disconnected from their respective local controllers while the first primary coil is supplying wireless power to the first wireless power receiver.

[0006] In some implementations, the master controller may be configured to disable the first local controller before changing the state of multiple switches in order to control which primary coils from the first primary coil group are coupled to the first local controller. Disabling the first local controller prevents current from flowing from the first local controller through the multiple switches while the state of multiple switches is being changed. After changing the state of multiple switches, the master controller may enable the first local controller to control which primary coils from the first primary coil group are coupled to the first local controller.

[0007] In some implementations, the multiple switches include a first set of switches configured to individually couple a first local controller to one primary coil of a first primary coil group, and a second set of switches configured to individually couple a second local controller to one primary coil of a second primary coil group.

[0008] In some implementations, the wireless power transmission device may include a plurality of local controllers, including at least a first local controller and a second local controller. At least the first local controller may include a communication unit that can receive communications from the first wireless power receiving device via the first primary coil when the first wireless power receiving device is in proximity to the first primary coil and the first local controller is coupled to the first primary coil. The first local controller may include a control unit configured to manage the operation of a driver in response to receiving communications from the first wireless power receiving device. The first local controller may include a driver configured to generate an electrical output to the first primary coil when the first primary coil is coupled to the first local controller via a plurality of switches.

[0009] In some implementations, the first local controller may be configured to determine a status signal to send to the master controller, which is at least partially based on communication from the first wireless power receiver, the wireless power transmission status, the electrical output generated in the first primary coil, a fault condition related to charging the first wireless power receiver, or any combination thereof. The first local controller may be configured to send the status signal to the master controller.

[0010] In some implementations, the master controller can be configured to determine, at least partially based on a status signal, that the first primary coil is not supplying wireless power to the first wireless powered device. The master controller can operate a number of switches to couple the first local controller to one or more other primary coils in the first primary coil group.

[0011] In some implementations, the master controller can be configured to determine, at least partially, based on a status signal, that the first primary coil is supplying wireless power to the first wireless power receiver. While the status signal indicates that the first primary coil is supplying wireless power to the first wireless power receiver, the master controller can prevent multiple switches from disconnecting the first local controller from the first primary coil.

[0012] In some implementations, while a status signal indicates that the first primary coil is supplying wireless power to the first wireless power receiver, the master controller may be configured to prevent multiple switches from coupling one or more adjacent primary coils near the first primary coil to their respective local controllers.

[0013] In some implementations, the master controller may be configured to sequentially couple the primary coils of a first primary coil group to a first local controller in multiple switches. The master controller may receive status signals from the first local controller for each primary coil of the first primary coil group. The status signals may indicate whether the first local controller has detected a first wireless power receiver in the coupled primary coil.

[0014] In some implementations, the master controller may be configured to simultaneously connect the first primary coil of the first primary coil group to the first local controller and the second primary coil of the second primary coil group to the second local controller for multiple switches. The first and second primary coils do not need to be adjacent.

[0015] In some implementations, the master controller may be configured to operate multiple switches such that each of the multiple primary coils is coupled to its respective local controller according to a pattern that prevents adjacent primary coils from being coupled simultaneously.

[0016] In some implementations, each primary coil group may include at least two primary coils that can be selectively coupled to a local controller. Each primary coil group may be coupled to its local controller via at least one switch.

[0017] In some implementations, the first primary coil group may include three primary coils that are selectively coupled to a first local controller via two switches.

[0018] In some implementations, the wireless power transmitter may include a charging pad on which multiple wireless power receivers can be placed. Multiple primary coils may be arranged in a pattern that is distributed and overlapping across multiple layers of the charging pad.

[0019] In some implementations, at least one subset of the multiple primary coils may be made of graphene.

[0020] In some implementations, the first local controller may be configured such that, when the first wireless power receiver is in proximity to the first primary coil and the first local controller is coupled to the first primary coil, at least the first primary coil of the first primary coil group transmits wireless power to the first wireless power receiver in response to communication from the first wireless power receiver via the first primary coil. The second local controller may be configured such that, when the second wireless power receiver is in proximity to the second primary coil and the second local controller is coupled to the second primary coil, at least the second primary coil of the second primary coil group transmits wireless power to the second wireless power receiver in response to communication from the second wireless power receiver via the second primary coil.

[0021] In some implementations, the first primary coil and the second primary coil do not have to be adjacent to each other. The first primary coil and the second primary coil may be configured to simultaneously transmit wireless power to the first wireless power receiving device and the second wireless power receiving device, respectively.

[0022] In some implementations, multiple switches may include mechanical or solid-state relays, which are control switches having normally closed (NC) and normally open (NO) terminals. The switching between the NC and NO terminals is managed by a master controller.

[0023] Another innovative aspect of the subject matter described herein can be implemented as a method implemented by a wireless power transmission device. In some implementations, the method may include the step of managing connections between a plurality of primary coils and their respective local controllers via a plurality of switches. The method may include the step of determining that a first primary coil of the plurality of primary coils is supplying wireless power to a first wireless power receiving device. The method may include the step of a master controller operating a plurality of switches such that, while the first primary coil is supplying wireless power to the first wireless power receiving device, one or more adjacent primary coils near the first primary coil remain disconnected from their respective local controllers.

[0024] In some implementations, multiple primary coils may be organized into a first primary coil group that can be individually coupled to a first local controller via at least a first subset of multiple switches, and a second primary coil group that can be individually coupled to a second local controller via a second subset of multiple switches.

[0025] In some implementations, the method may include a step of disabling the first local controller before changing the state of multiple switches in order to control which primary coils of the first primary coil group are coupled to the first local controller. Disabling the first local controller prevents current from flowing from the first local controller through the multiple switches while the state of multiple switches is being changed. After changing the state of multiple switches, the method may include a step of enabling the first local controller to control which primary coils of the first primary coil group are coupled to the first local controller.

[0026] In some implementations, the method may comprise the step of: receiving, by a first local controller, communication from a first wireless power receiving device via a first primary coil when the first wireless power receiving device is proximate to the first primary coil and the first local controller is coupled to the first primary coil. The method may comprise the step of determining, by the first local controller, a status signal to be transmitted to a master controller, wherein the status signal is based at least in part on communication from the first wireless power receiving device, a wireless power transmission status, an electrical output generated at the first primary coil, a fault condition associated with charging of the first wireless power receiving device, or any combination of the foregoing. The method may comprise the step of transmitting the status signal from the first local controller to the master controller.

[0027] In some implementations, the method may comprise the step of determining, based at least in part on the status signal, that the first primary coil is not supplying wireless power to the first wireless power receiving device. The method may comprise the step of actuating a plurality of switches to couple the first local controller to one or more other primary coils in a first group of primary coils.

[0028] In some implementations, the method may comprise the step of determining, by a master controller based at least in part on the status signal, that the first primary coil is supplying wireless power to the first wireless power receiving device. The method may comprise the step of preventing, by the master controller, the plurality of switches from disconnecting the first local controller from the first primary coil while the status signal indicates that the first primary coil is supplying wireless power to the first wireless power receiving device.

[0029] In some implementations, the method may comprise the step of, while the status signal indicates that the first primary coil is wirelessly supplying power to a first wireless power receiving device, preventing a plurality of switches from coupling one or more adjacent primary coils located near the first primary coil to respective local controllers.

[0030] In some implementations, the method may comprise the step of causing a plurality of switches to sequentially couple primary coils in a first primary coil group to a first local controller. The method may comprise, for each primary coil in the first group of primary coils, the step of receiving a status signal indicating whether the first local controller has detected the first wireless power receiving device at the coupled primary coil from the first local controller.

[0031] In some implementations, the method may comprise the step of causing a plurality of switches to simultaneously couple a first primary coil of a first primary coil group to a first local controller, and a second primary coil of a second primary coil group to a second local controller. The first primary coil and the second primary coil may be non-adjacent.

[0032] In some implementations, the method may comprise the step of operating a plurality of switches to couple each of the plurality of primary coils to a respective local controller according to a pattern that prevents adjacent primary coils from being coupled simultaneously.

[0033] The details of one or more implementations of the subject matter described in the present disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims. It should be noted that the relative dimensions in the following figures may not be drawn to scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] [Figure 1]This section outlines the components related to exemplary wireless power systems in several implementation forms. [Figure 2A] This example shows a wireless power transmission device having multiple layers of primary coils arranged in overlapping patterns in several implementation configurations. [Figure 2B] Figure 2a shows an exemplary wireless power transmission device in which multiple wireless power receiving devices in several implementation configurations are being charged simultaneously. [Figure 3] This shows an exemplary primary coil group that can be individually coupled to a local controller in several implementation configurations. [Figure 4] This shows an exemplary primary coil group in several implementation configurations, and a local controller that can be managed by a master controller. [Figure 5] This section shows an example configuration using multiple primary coils in several different implementations. [Figure 6] This section shows examples of muting adjacent primary coils using several implementation methods. [Figure 7] This document illustrates several exemplary patterns of digital ping managed by a master controller in various implementation configurations. [Figure 8] A flowchart illustrating exemplary processes for wireless power transmission in several implementation configurations is shown. [Figure 9] This diagram shows an exemplary block diagram of an electronic device for use in a wireless power system in several implementation configurations. Similar reference numbers and symbols in the various drawings indicate similar elements. [Modes for carrying out the invention]

[0035] The following description applies to specific implementations for the purpose of illustrating innovative aspects of the present disclosure. However, those skilled in the art will readily recognize that the teachings herein can be applied in numerous different ways. The implementations described may be implemented by any means, apparatus, system, or method for transmitting or receiving wireless power.

[0036] Conventional wireless power systems may include a wireless power transmitter and a wireless power receiver. The wireless power transmitter may include a primary coil that transmits wireless energy (as a wireless power signal) to a corresponding secondary coil in the wireless power receiver. The primary coil is the wireless energy source of the wireless power transmitter (such as inductive energy or magnetic resonance energy). The secondary coil of the wireless power receiver receives the wireless energy. Wireless power transmission is more efficient when the primary and secondary coils are located in close proximity. Conversely, if the primary and secondary coils are misaligned, efficiency may decrease (or power transmission may stop). Conventional wireless power transmitters may include a controller that enables or disables wireless energy transmission based on how close the wireless power receiver is to the wireless power transmitter. For example, wireless energy transmission may depend on the degree of alignment between the transmitting and receiving coils. In this disclosure, alignment refers to the spatial relationship between the secondary coil of the wireless power receiver and the primary coil of the wireless power transmitter.

[0037] To address misalignment concerns and increase positioning flexibility, some wireless power transmitters may include multiple primary coils. For example, primary coils may be located on the charging surface of a wireless power transmitter. The primary coils may be arranged in overlapping or non-overlapping configurations. The arrangement of the primary coils (overlapping or non-overlapping) may be designed to minimize, reduce, or eliminate dead zones. Depending on the orientation and position of the wireless power receiver on the charging surface, different primary coils may be voltaged to power the corresponding secondary coils of the wireless power receiver. Thus, the wireless power transmitter can support a degree of positional freedom that allows the wireless power receiver to be charged regardless of its position or orientation relative to the charging surface. Furthermore, multiple wireless power receivers may be charged simultaneously using different primary coils of the wireless power transmitter. However, when a wireless power transmitter has multiple primary coils, unused primary coils may cause undesirable electromagnetic interference (EMI) to nearby primary coils supplying wireless power to wireless power receivers.

[0038] According to this disclosure, a wireless power transmission device may have a plurality of primary coils that can be selectively and individually coupled to a local controller. The local controller may include communication functions, control functions, drivers, or other power signal generation circuits. In some implementations, the local controller (if connected to one of the primary coils) can implement wireless power transmission in accordance with a standardized wireless power specification, such as the Qi® specification provided by the Wireless Power Consortium. For example, the wireless power transmission device may include a plurality of primary coils, each of which can be connected to the local controller to conform to the Qi specification.

[0039] In some implementations, primary coils may be organized into groups of primary coils that can be managed separately. These groups of primary coils may be referred to as zones in some aspects of this disclosure. Each zone of a wireless power transmission device may have a separate zone circuit that can be connected to the primary coils within the zone, allowing each primary coil to be energized independently. For example, a zone circuit may include a local controller, driver, voltage regulator, tank circuit capacitor, etc., common to all primary coils associated with the zone. Zone circuits can be connected to different primary coils using one or more relays or switches. A relay is a type of switch. For example, a relay may be an electromechanical switch or a solid-state switch that can be controlled by a control signal. In some implementations, a relay may have a common terminal, a normally closed (NC) terminal, and a normally open (NO) terminal. When the control signal is not functioning (not energized), the relay's internal switching mechanism may connect the common terminal and the NC terminal. When the control signal is functioning (energetic), the internal switching mechanism may connect the common terminal and the NO terminal. In some implementations, a relay may be a packaged electrical component that includes a switch that is operated or stopped by a control signal. Therefore, the terms relay, controllable switch, or switch may be used interchangeably herein. While the examples in this disclosure refer to relays for brevity, it should be understood that other types of switches may be used to connect zone circuits to primary coils.

[0040] A relay (or other type of switch) may be used to connect the primary coil to the local controller. The state of one or more relays may determine which primary coil in the zone is connected to the zone circuit. The zone circuit is common to all primary coils in the zone, but only one primary coil can use the zone circuit at a time. The local controller may use digital ping or other current sensing techniques to determine if a wireless powered device is located near the primary coil to which the local controller is currently connected. For example, if the local controller receives communication from a wireless powered device in response to a ping operation, the local controller can determine that the wireless powered device is in proximity to the primary coil currently connected to the local controller. The local controller can cause the primary coil to supply wireless energy to the secondary coil of the wireless powered device. For example, the local controller can operate a driver, and the connected primary coil can transmit wireless power. While the first primary coil of the zone is supplying power to the wireless powered device, the other primary coils remain disconnected based on the state of the relays.

[0041] In some implementations, a master controller can manage the state of relays within a zone to effectively enable or disable different primary coils. Furthermore, a wireless power transmitter may include multiple groups of primary coils (zones) that can be connected to or disconnected from their respective zone circuits. The master controller can manage relays within multiple zones to prevent adjacent primary coils from operating or transmitting pings while a first primary coil is supplying power to a wireless power receiver. For example, if a voltage is applied to an adjacent primary coil, it may generate undesirable EMI, potentially interrupting the wireless power session of the first primary coil or affecting the efficiency of the wireless power session. Therefore, in some implementations, the master controller can disable or disconnect (also called "mute") adjacent primary coils to prevent them from transmitting energy or transmitting pings. Muting an adjacent primary coil can be achieved by either preventing the adjacent primary coil from being connected to a local controller via a relay, or by disabling a local controller in the adjacent zone.

[0042] In some implementations, the master controller can disable the zone circuitry before changing the state of the zone's relays. The power connected through the relays can cause current to flow when the relays switch, potentially leading to relay damage, reduced relay lifespan, or both. Therefore, in some implementations, the master controller can disable or stop the local controllers within a zone before making any changes to the relay connections within that zone. After a short time following the change in the relay state, the master controller can re-enable or restart the local controllers. This allows the relays to be completely switched in a zero-current environment, extending their lifespan and improving the reliability of the local controllers when detecting wireless powered devices.

[0043] In some implementations, the master controller may use patterns to determine which primary coils in different zones should be connected to their respective local controllers. For example, if the first primary coil is connected to the first local controller to perform a digital ping or detection procedure, the master controller may choose not to connect adjacent primary coils to their respective local controllers. This pattern can be used to alternate which sets of primary coils send pings, preventing adjacent or nearby primary coils from sending pings simultaneously.

[0044] In some implementations, the primary coil is made of a material that improves the reliability and efficiency of the wireless power transmission device. For example, part or all of the primary coil may be made of graphene, which has higher conductivity and smaller size than conventional materials (such as copper wire). Smaller size means thinner overlapping layers of primary coil, which can lead to more uniform power transmission between different layers of primary coil.

[0045] Certain implementations of the subject matter described herein may be implemented to achieve one or more of the following potential benefits. In some implementations, the described techniques can be used to enable charging of one or more wireless powered devices in various locations and orientations. The efficiency of the wireless power transmission can be improved by selectively connecting separate primary coils for each zone to a local controller. The electronics within the wireless power transmission may use a modular design with common components for groups of primary coils forming different zones. The cost and complexity of the wireless power system can be reduced by using fewer local controllers compared to a system using one local controller for each primary coil. Furthermore, the ability to mute adjacent primary coils may improve the efficiency, speed, and reliability of powering wireless powered devices. For example, muting adjacent primary coils can prevent disturbances that would otherwise affect the charging time for charging wireless powered devices.

[0046] Figure 1 shows an overview of components related to exemplary wireless power systems in several implementation configurations. The wireless power transmission device 110 may include a power supply 180 configured to supply power to various zones within the wireless power transmission device 110. The power supply 180 can convert alternating current (AC) to direct current (DC). The wireless power system 100 includes a wireless power transmission device 110 having a plurality of primary coils 120 (shown as primary coils 121, 122, 123, 124, 125, and 126). Each of the primary coils 120 may be associated with a different zone circuit. For example, a first group of primary coils 121, 122, and 123 may be associated with a first zone 130. A second group of primary coils 123, 125, and 126 may be associated with a second zone 150. The first zone 130 may include a common zone circuit (including a first local controller 131). In this disclosure, the terms zone circuit and local controller may be used interchangeably. However, it is understood that the zone circuit may include a local controller and other circuit components (including resistors, capacitors, drivers, etc.). Each primary coil may be a wire coil that transmits a wireless power signal (sometimes called wireless energy). Each primary coil may transmit wireless energy using an inductive field or a magnetic resonance field (when connected to a local controller via a relay). The zone circuit may include components (not shown) for preparing the wireless power signal. For example, the zone circuit may include one or more switches, drivers, capacitors, or other components. An example of a zone circuit is shown in Figure 3. In some implementations, some or all of the zone circuit is embodied as an IC that implements the features of the present disclosure. Similar to the first zone 130, the second zone 150 may have a second local controller 132.

[0047] One or more relays 141 within the first zone 130 can control which of the primary coils 121, 122, and 123 are connected to the first local controller 131. Similarly, relay 142 can control which of the primary coils 124, 125, and 126 are connected to the second local controller 132. An example of relay 141 is shown in Figure 3. The master controller 170 can manage relays 141 and 142 to control which of the primary coils in each zone 130, 150 are coupled to the local controllers. For example, in Figure 1, the master controller 170 has configured relay 141 to connect the first primary coil 121 to the first local controller 131. While the first primary coil 121 is connected to the first local controller 131, the other primary coils 122 and 123 within the first zone 130 are disconnected. The master controller 170 connects the second primary coil 125 to the second local controller 132, while the other primary coils 124 and 126 in the second zone 150 are disconnected.

[0048] Various methods can be used to implement the master controller 170, including microcontrollers, dedicated processors, integrated circuits, and application-specific integrated circuits (ASICs). In some implementations, the master controller may be placed alongside or integrated with one of the local controllers (such as the first local controller 131 or the second local controller 132). For example, an integrated circuit (IC) may implement the functions of both the master controller and one or more local controllers. Furthermore, in some implementations, a local controller may perform some of the functions described as those of a master controller (in addition to the functions of a local controller), including polling other local controllers, muting adjacent primary coils, enabling / disabling other local controllers, switching connections between distant primary coils and other local controllers, or any combination thereof.

[0049] The first local controller 131 may be configured to detect the presence or proximity of a wireless powered device when connected to one of the primary coils 121, 122, or 123 in the first zone. For example, the first local controller 131 may cause the connected primary coil to periodically transmit a detection signal and measure a coil current or load change indicating the presence of an object near the primary coil. In some implementations, the local controller may detect pings, wireless communications, load modulation, etc., to determine that the wireless powered device is located on the wireless powered device. In some implementations, the transmitting circuit may perform detections intermittently or operate independently to detect the wireless powered device. In some implementations, the transmitting circuit may be configured to perform detection steps in a pattern such that adjacent primary coils perform detection steps at deterministic times to reduce interference between adjacent coils.

[0050] In the example in Figure 1, the first wireless power receiver 210 may be detected by the first primary coil 121. The first wireless power receiver 210 has a secondary coil 220. The wireless power receiver may be any type of device capable of receiving wireless power, including mobile phones, computers, laptops, peripherals, gadgets, robots, vehicles, etc. If the wireless power receiver (such as the first wireless power receiver 210) is placed on a wireless power transmitter 110 near the first primary coil 121, and the first local controller 131 is connected to the first primary coil 121 via a relay 141, the first local controller 131 can detect its presence. For example, during the detection phase, the first primary coil 121 may transmit a detection signal (sometimes called a ping). The coil current in the first primary coil 121 may be measured to determine whether it exceeds a threshold indicating the presence of an object within the electromagnetic field of the first primary coil 121. If an object is detected, the first local controller 131 may wait for a handshake signal (identification signal, setup signal, etc.) from the first wireless power receiver 210 to determine whether the object is a wireless power receiver or a foreign object. The first wireless power receiver 210 may communicate the handshake signal using a series of load changes (load modulation, etc.). Load changes can be detected by a voltage or current sensing circuit of a coil and may be detected by the first primary controller 131. The first controller 131 may detect the load fluctuation and recover communication from the first wireless power receiver 210. The communication may include information such as charge level, requested voltage, power received, receiver power capability, and support for wireless charging standards.

[0051] The first wireless power receiving device 210 may include a secondary coil 220, a rectifier 230, a receiver (RX) controller 240, and an optional battery module 250. In some implementations, the battery module 250 may have an integrated charger (not shown). The secondary coil 220 can generate an induced voltage based on the wireless power signal received from the first primary coil 121. A capacitor (not shown) may be in series between the secondary coil 220 and the rectifier 230. The rectifier 230 can rectify the induced voltage and supply the rectified voltage to the battery module 250. The battery module 250 may be located within the wireless power receiving device 210 or may be an external device coupled by an electrical interface. The battery module 250 may include a charging stage and protection circuits such as a temperature detection circuit, an overvoltage protection circuit, and an overcurrent protection circuit. Alternatively, the receiver controller 240 may include a battery charge management module for collecting and processing information regarding the charge state of the battery module 250. In some implementations, the receiving controller 240 may be configured to communicate with the first local controller 131 using load modulation via the secondary coil 220.

[0052] In the example in Figure 1, the first wireless power receiver 210 is detected by the first primary coil 121, so the master controller 170 can maintain the connection between the first primary coil 121 and the first local controller 131 via relay 141. Therefore, the other primary coils 122 and 123 in the first zone 130 remain disconnected and do not send pings or cause interference. However, the adjacent primary coil 126 may interfere with the first primary coil 121. Therefore, the master controller can prevent relay 142 from connecting primary coil 126 to the second local controller 132. In other words, the master controller may be configured to prevent adjacent primary coils from connecting to their respective local controllers, even if the adjacent primary coils are part of different zones.

[0053] In the example shown in Figure 1, the second wireless power receiver 260 is located near the second primary coil 125. As described above, the second local controller 132 can control the second primary coil 125 separately from other zones. Thus, the second local controller 132 may cause the second primary coil 125 to transmit wireless power to the second wireless power receiver 260, and the first local controller 131 may cause the first primary coil 121 to transmit wireless power to the first wireless power receiver 210. Furthermore, the first local controller 131 and the second local controller 132 may individually manage parameters related to wireless charging in their respective primary coils. For example, for the first primary coil 121 and the second primary coil 125, the voltage level, resonant frequency, power level, or other parameters may differ based on the type of wireless power receiver or the charge level of their respective batteries.

[0054] In some implementations, the master controller 170 can coordinate the operation of multiple local controllers. For example, the master controller 170 may manage the detection stage pattern for each zone based on the recognition of the adjacency of the primary coils.

[0055] The example in Figure 1 shows only six primary coils 121, 122, 123, 124, 125, and 126 organized into two zones 130 and 150, but the number of primary coils and zones may differ. For example, the number of primary coils associated with each zone may be less than or more than three. Furthermore, the primary coils may be arranged in overlapping or layered configurations, with different zones defined between the configurations. In some implementations, zones may be based on which primary coils are close to each other, so that if zones share a common zone circuit, a relay for one zone will effectively disable adjacent primary coils based on the zone relationships. Alternatively, zones may include primary coils distributed throughout the entire wireless power transmission device.

[0056] Figure 2A shows an exemplary wireless power transmission device having multiple layers of primary coils arranged in overlapping patterns in several implementation configurations. The exemplary wireless power transmission device 200 includes 18 primary coils arranged in two overlapping layers. Here again, the number and arrangement of primary coils are shown as examples. Other numbers of primary coils, numbers of layers, or arrangements may be used. Furthermore, although the primary coils shown in Figure 2 appear circular to help illustrate the partially overlapping pattern, non-circular primary coils may be used in other designs. For example, the primary coils may be square (or rounded square) as shown in Figures 5 to 7. The design in Figure 2 can be used to illustrate how a multilayer system can provide a partially overlapping arrangement of primary coils in a wireless power transmission device. In this disclosure, a partially overlapping arrangement may include a design in which the side portions overlap (or coincide).

[0057] As shown in Figure 2A, multiple primary coils are distributed between the first layer 152 and the second layer 153. For example, the first primary coil 121 is shown on the first layer 152 along with several other primary coils. The second primary coil 125 is shown on the second layer 153 along with other primary coils.

[0058] Figure 2B shows an exemplary wireless power transmitter of Figure 2A in which multiple wireless power receivers in several implementation configurations are being charged simultaneously. Figure 2B includes layers 152 and 153 as a combination diagram 154 showing the overlapping state of the coils. In some implementation configurations, the number of coils and overlaps may be such that multiple primary coils cover substantially the entire charging surface 155.

[0059] In addition to the wireless power transmitter 200, Figure 2B shows a first wireless power receiver 210 and a second wireless power receiver 260 placed on the charging surface 155. The first wireless power receiver 210 can latch and receive wireless power from the first primary coil 121 based on its position on the transmitting circuit. Similarly, the second wireless power receiver 260 can latch and receive wireless power from the second primary coil 125. Various optional features may be incorporated into the design of the wireless power transmitter. For example, in some implementations, ferrite material may be used in part of the wireless power transmitter to maintain a consistent electromagnetic field. Ferrite material may be used to uniformly distribute the electromagnetic field.

[0060] Figure 3 shows an exemplary group of primary coils that can be individually coupled to a local controller in several implementation configurations. The exemplary first zone 130 in Figure 3 is one of many designs available in this disclosure. In the design of Figure 3, the first zone 130 includes a first group of primary coils 121, 122, and 123, as well as a zone circuit 310. The zone circuit 310 includes a first local controller 131 that receives DC power using a DC input line 350 electrically coupled to a power supply 180. The DC power may be a specific voltage (e.g., 5V or 12V). Alternatively, the local controller may include a power adjustment stage to meet the voltage requirements of submodules within the local controller. The same DC voltage may be electrically coupled to several switches in the zone circuit 310, such as switches 330. Switches 330 may include semiconductor switches such as metal-oxide-semiconductor field-effect transistors (MOSFETs) and insulated-gate bipolar transistors (IGBTs). Alternatively, switches 330 may include mechanical switches. In the example in Figure 3, each switch may be paired with a diode 320. Other components (such as drivers) are not shown in the figure but may be included in the path.

[0061] The first local controller 131 may also switch the device to convert the power supply 180 from a DC output to an AC output across the center point of the two legs of the bridge. The coil voltage VAC is supplied to the local controller using link 340. Switches can be used to control the voltage applied to the capacitor and primary coil pair. For example, the first local controller 131 can change the duty cycle of each switch leg, the phase angle of the applied voltage between the switch legs, the frequency of the applied voltage, or a combination thereof. The first local controller 131, switches, drivers, diodes, etc., may be considered as a zone circuit 310. In some implementations, the drivers may be integrated into the first local controller 131. Furthermore, the first local controller 131 may control the output of the zone circuit 310 using control lines (marked 1, 2, 3, 4) to each switch. The first local controller 131 and switches may be electrically coupled to a ground wire 360 ​​to complete the circuit. The capacitor and primary coil form a resonant circuit.

[0062] In some implementations, the zone circuit 310 may include a coil current sensing circuit (not shown). The zone circuit 310 may have the function of detecting load changes in the first primary coil 121. The coil current sensing circuit may be a current sensor connected in series with the first primary coil 121. The first local controller 131 may determine the presence or absence of an object based on the load changes measured by the coil current sensing circuit. The local controller may use a sensing current, a sensing voltage VAC340, or a combination thereof to determine the load changes. A communication unit (not shown) may also be present or incorporated into the first local controller 131. The communication unit can monitor the load changes measured by the coil current sensing circuit and / or VAC340 and decode load modulation data. The communication unit can receive identification information (ID), charge status information, voltage control information, or other information reported by the wireless power receiving device.

[0063] Figure 3 also shows relay 141. Relay 141 includes a first relay 311 and a second relay 312. In the example in Figure 3, the two relays can be used to switch the coupling of three primary coils 121, 122, and 123 with the zone circuit 310. Relays 311 and 312 may each have two states: normally open (NO) and normally closed (NC). A DC voltage 180 may be used to power the coils (not shown) of relays 311 and 312 to switch the connection from NC to NO based on a control signal from a master controller (not shown). By changing the states of relays 311 and 312, it is possible to connect the zone circuit 310 to a specific coil of the primary coil. Table 1 shows the states of relays 311 and 312 to which different primary coils will be connected with the zone circuit 310. The examples in Table 1 and Figure 3 are provided for illustrative purposes only, and those skilled in the art can implement other combinations, relay circuits, or states. [Table 1]

[0064] Figure 4 shows exemplary primary coil groups in several implementation configurations and local controllers that can be managed by the master controller. Based on the description in Figure 3, Figure 4 shows how the master controller 170 can manage the operation of the first zone 130, which includes switches 311 and 312 and the first local controller 131. Other parts of the zone circuit are omitted from Figure 4 for brevity.

[0065] The master controller 170 may control a first control link 411 to a first relay 311 and a second control line 412 to a second relay 312. The first and second control lines may also be on / off signals to switch the states of relays 311 and 312. However, as described above, if the states of relays 311 and 312 are switched while current is flowing from the first local controller 131 to one of the primary coils, this may reduce the lifespan of the relays. Therefore, in some implementations, the master controller 170 may have a control line 431 to the first local controller 131. The control line 431 may be used to enable or disable the first local controller 131. For example, the control line 431 may signal the first local controller 131 to disable the electronics of the local controller (or any other zone circuit controlled by the local controller) so that no current flows to relays 311 and 312. After disabling the first local controller 131, the master controller 170 may change the state of relays 311 and 312. The master controller 170 may delay sending an enable signal to the first local controller 131 via the control line 431 for a certain period of time (e.g., 100 milliseconds).

[0066] In some implementations, the master controller 170 may also receive status signals via a control line 441 from the first local controller 131 to the master controller 170. For example, the status signal may indicate to the wireless powered device whether the first local controller 131 is currently latched (powering). In other examples, the status signal may indicate an operating state, a charging state, or other information available from the first local controller 131. In some implementations, the first local controller may determine the status signal based on a state such as communication from the first wireless powered device, a wireless power transmission state, an electrical output generated to the first primary coil, a fault state related to charging the first wireless powered device, or any combination thereof. In some implementations, the status signal may be an "on" or "off" signal indicating whether the first local controller is successfully charging the wireless powered device. In some other implementations, the status signal may include a formatted message (e.g., tag-length-value (TLV), information elements, or some other format for conveying additional status information). In other implementations, the status signal may be transmitted as a digital pulse signal via control line 441. The master controller may be configured to capture the digital pulse signal and determine the state of the first local controller 131.

[0067] In some implementations, a status signal (or another interface between the first local controller and the master controller) may indicate a fault condition (such as overcurrent, foreign object detection, poor quality factors, or mismatch). In the event of a fault condition, the master controller may disable the first local controller 131 using control line 431. For example, if a status signal indicates that the first local controller 131 has a poor connection to the wireless powered device or that a foreign object has been detected, the master controller 170 may disable the first local controller 131, change the state of relays 311 and 312, and then re-enable the first local controller 131 to see if another primary coil can achieve a better connection to the wireless powered device.

[0068] Figure 5 shows an exemplary arrangement using multiple primary coils in several implementation forms. The charging surface of Figure 5 shows an arrangement of 13 primary coils (numbered 1-13) grouped into five zones. The primary coils in each zone are given similar grayscale shading for ease of reference. The first local controller 131 (related to the first zone) can be coupled to any of primary coils 1, 2, and 6 via relays. The second local controller 132 (related to the second zone) can be coupled to any of primary coils 3, 4, and 8 via relays. The third local controller 133 (related to the third zone) can be coupled to any of primary coils 5 and 10 via relays. Note that the first and second zones may have two relays (as described in Figure 3), but the third zone may have only one relay, since it only has two primary coils. The fourth local controller 134 (related to the fourth zone) can be coupled to any of primary coils 7, 11, and 12 via relays. The fifth local controller 135 (related to the fifth zone) can be coupled to either of the primary coils 9 and 13 via a relay. This arrangement is used to illustrate the exemplary scenarios in Figures 6 and 7. Although the diagrams in Figures 5-7 show the coils as non-overlapping, in some implementations the coils may partially overlap.

[0069] Figure 5 shows that the master controller 170 can manage multiple zones. In particular, the master controller 170 may have control lines to each of the five zones in Figure 5 (similar to the control lines 411, 412, 431, and 441 described in Figure 4). The master controller 170 can use control lines to relays in each zone to control which primary coils of the entire wireless power transmission system are connected to their respective local controllers 131, 132, 133, 134, and 135.

[0070] Figure 6 shows examples of muting adjacent primary coils in several implementation configurations. In Figure 6, primary coil number 6 is charging a wireless power receiver (not shown). Due to the zone and relay equipment configuration of the first zone, the other primary coils 1 and 2 in the first zone are not connected to the first local controller 131. To prevent interference with primary coil 6, the master controller 170 may mute the other adjacent primary coils 5, 7, 10, and 11. For example, the master controller 170 may completely disable the third local controller 133, or control the relays in the third zone so that primary coils 5 and 10 are not connected to the third local controller 133. Similarly, the master controller 170 may control the relays in the fourth zone so that primary coils 7 and 11 are not connected to the fourth local controller 134. Note that primary coil 12 in the fourth zone can still be used because it is not adjacent to the functioning primary coil 6. Therefore, the master controller 170 may control the relays in the fourth zone to connect the primary coil 12 to the fourth local controller 134. The fourth local controller 134 may use the primary coil 12 to periodically send pings to determine whether a second wireless powered device may be placed in a portion of the charging pad. Similarly, the other primary coils 3, 4, 8, 9, and 13 that are not adjacent to the primary coil 6 may be coupled to their respective local controllers so that they can send pings to detect other wireless powered devices that can be charged by their respective local controllers.

[0071] Figure 7 shows exemplary patterns of digital ping managed by a master controller in several implementation configurations. The master controller 170 can control the connection of each primary coil to its respective local controller, thereby reducing or eliminating the number of adjacent primary coils transmitting pings simultaneously. In the example in Figure 7, there may be four sets of coils transmitting pings at different times (distributed across the entire zone). The sets of coils are indicated by different hatch marks for reference. It should be noted that the exemplary pattern in Figure 7 is for illustrative purposes only, and actual patterns may differ depending on the implementation configuration. Furthermore, for simplicity, Figure 7 is a diagram showing a point in time when all primary coils may be involved in the ping transmission pattern, as the wireless powered device is not currently placed on the charging pad.

[0072] In the exemplary pattern shown in Figure 7, during the first time period, primary coils 1, 3, 10, and 12 can send pings to detect the presence of wireless powered devices while the remaining primary coils are disconnected from their respective local controllers. After the first time period, the master controller 170 can 1) disable local controllers 131, 132, 133, 134, and 135, 2) disconnect primary coils 1, 3, 10, and 12, 3) connect local controllers 131, 132, 133, 134, and 135 to a different set of primary coils (primary coils 2, 4, 11, and 13), and 4) re-enable local controllers 131, 132, 133, 134, and 135. Thus, during the first time period, primary coils 1, 3, 10, and 12 send pings, and during the second time period, primary coils 2, 4, 11, and 13) send pings. This pattern ensures that, in each time zone, adjacent primary coils are not connected to an enabled local controller. Continuing this pattern, the third time zone may include primary coils 6 and 7. The fourth time zone may include primary coils 5, 7, and 9.

[0073] Figure 8 shows a flowchart illustrating an exemplary process for wireless power transmission in several implementation configurations. Flowchart 800 begins in block 810. In block 810, the wireless power transmission device can manage the connections between multiple primary coils and their respective local controllers via multiple relays. For example, a master controller can enable or disable relays to change the electrical connection between a selected primary coil and local controllers in the same zone. In block 820, the wireless power transmission device can determine that a first primary coil among the multiple primary coils is supplying wireless power to a first wireless power receiver. For example, the wireless power transmission device can receive a status signal from a first local controller connected to the first primary coil. In block 830, the wireless power transmission device can be controlled by the master controller to operate multiple relays such that one or more adjacent primary coils near the first primary coil remain disconnected from their respective local controllers while the first primary coil is supplying wireless power to the first wireless power receiver. For example, a master controller can programmatically determine adjacent primary coils and then send control signals to relays within that zone to ensure that those adjacent primary coils disconnect from the local controllers within that zone.

[0074] Figure 9 shows a block diagram of an exemplary electronic device for use in a wireless power system in several implementation configurations. In some implementation configurations, the electronic device 900 may be a wireless power transmission device (such as the wireless power transmission device 190). The electronic device 900 may include a processor 902 (which may include multiple processors, multiple cores, multiple nodes, or multithreading, depending on the configuration). The electronic device 900 may also include memory 906. Memory 906 may be system memory or one or more of the computer-readable media described herein that are feasible. The electronic device 900 may also include a bus 990 (such as PCI, ISA, PCI-Express, HyperTransport®, InfiniBand®, NuBus®, AHB, AXI, etc.).

[0075] The electronic device 900 may include multiple local controllers 962 configured to be coupled to multiple primary coils 966 via relays 964. A master controller 970 (similar to the master controller 170 described herein) may control the activation / deactivation of the local controllers 962 and the state of the relays 964. Furthermore, the master controller 970 may receive status signals from the local controllers 962 regarding the current charge state or wireless powered device detection. In some implementations, the local controllers 962 may be distributed within the processor 902, memory 906, and bus 990. The local controllers 962 may perform some or all of the operations described herein, including the operations of local controllers 131, 132, 133, 134, and 135. Memory 906 may contain computer instructions that can be executed by the processor 902 to implement the functions of the implementations described in Figures 1 to 7. Any one of these functions may be partially (or entirely) implemented in hardware or in the processor 902. For example, the functionality may be implemented in a coprocessor such as a peripheral device or card, in addition to the logic implemented in the processor 902, using an application-specific integrated circuit. Furthermore, the implementation may involve fewer or more components not shown in Figure 9. The processor 902, memory 906, and local controller 962 may be coupled to the bus 990. Although shown as coupled to the bus 990, the memory 906 may be coupled to the processor 902.

[0076] Figures 1–9 and the operations described herein are examples intended to aid in understanding exemplary implementations and should not be used to limit potential implementations or the scope of claims. Some implementations may perform additional operations, fewer operations, operations in parallel or in different orders, and several different operations.

[0077] Where used herein, the phrases “at least one of” or “one or more of” the list of items refer to any combination of these items, including single members. For example, “at least one of a, b, or c” is intended to cover the possibilities of a only, b only, c only, a and b combination, a and c combination, b and c combination, and a, b, and c combination.

[0078] The various exemplary components, logic, logic blocks, modules, circuits, operations, and algorithmic processes described in relation to the implementations disclosed herein may be implemented as electronic hardware, firmware, software, or a combination of hardware, firmware, or software, including the structures disclosed herein and their structural equivalents. Hardware, firmware, and software compatibility is generally described with respect to functionality and is shown in the various exemplary components, blocks, modules, circuits, and processes described above. Whether such functionality is implemented in hardware, firmware, or software depends on the specific application and the design constraints imposed on the overall system.

[0079] Hardware and data processing devices used to implement the various exemplary components, logic, logic blocks, modules, and circuits described in relation to the embodiments disclosed herein may be implemented or carried out using general-purpose single-chip or multi-chip processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices (PLDs), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration. In some implementations, specific processes, operations, and methods may be carried out by circuits specialized for a given function.

[0080] As described above, in some embodiments, the implementations of the subject matter described herein can be implemented as software. For example, various functions of the components disclosed herein, or various blocks or steps of the methods, operations, processes, or algorithms disclosed herein, can be implemented as one or more modules of one or more computer programs. Such computer programs may include non-temporary processors or computer executable instructions encoded on one or more tangible processors or computer-readable storage media for execution by or control of a data processing device including the components of the devices described herein. Such storage media may include, but are not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other media that can be used to store program code in the form of instructions or data structures. The combinations described herein should also be included within the scope of storage media.

[0081] Various modifications to the implementations described herein may be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other implementations without departing from the scope of this disclosure. Therefore, the claims are not intended to be limited to the implementations shown herein, but should be given the broadest scope consistent with the disclosures, principles, and novel features disclosed herein.

[0082] Furthermore, various features described herein in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented separately or in any suitable partial combination in multiple implementations. Thus, features are described above as functioning in a particular combination and may initially be claimed as such, but one or more features from a claimed combination may, in some cases, be removed from that combination, and the claimed combination may cover partial combinations or variations of partial combinations.

[0083] Similarly, while diagrams show operations in a specific order, this should not be interpreted as meaning that such operations must be performed in a specific or sequential order, or that all shown operations must be performed, in order to obtain the desired result. Furthermore, diagrams can schematically represent one or more exemplary processes in the form of flowcharts or flow diagrams. However, other operations not shown can be incorporated into the schematically shown exemplary processes. For example, one or more additional operations can be performed before, after, simultaneously with, or in between any of the operations shown. In some situations, multitasking and parallel processing may be advantageous. The separation of various system components in the implementation forms described above should not be interpreted as requiring such separation in all implementation forms, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged in multiple software products.

Claims

[Claim 1] A wireless power transmission device, Multiple primary coils capable of selectively and individually transmitting wireless power, A plurality of switches, each capable of individually connecting one or more of the plurality of primary coils to its respective local controller, Master controller and The master controller is equipped with, Each of the plurality of switches is individually coupled to a local controller with at least one of the plurality of primary coils, thereby enabling ping operation via the first primary coil. While the first primary coil is coupled to the local controller, the first wireless power receiving device is detected based on communication or ping response from the first wireless power receiving device. The local controller transmits the wireless power to the first wireless power receiving device via the first primary coil. While the first primary coil is transmitting wireless power to the first wireless power receiving device, the plurality of switches prevent the coil adjacent to the first primary coil from being coupled to any local controller. A wireless power transmission device configured in such a way.

Images