Energy storage device for power receiver of wireless power system

Abstract

The present disclosure provides systems, methods, and apparatuses for energy storage units incorporated in wireless appliances used in wireless power systems. The energy storage units can provide energy to a bias supply circuit of a power receiver. When harvested bias power is unavailable or insufficient, the energy storage units can provide energy to operational components of the power receiver, such as a controller, a load disconnect switch, a communication unit, a memory or timer, among other examples.

Description

[0001] Related applications This application claims priority to Indian Provisional Patent Application No. 202411001388, filed on January 8, 2024, the disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates in general to aspects of wireless power and energy storage devices in wireless appliances that relate to wireless power systems.

[0003] Related technical descriptions A wireless power system includes a power transmitter (PTx) and a power receiver (PRx). Inductive coupling allows wireless power to be transferred between the primary coil of the power transmitter and the secondary coil of the power receiver. The primary coil of the power transmitter generates an electromagnetic field during the power state of the wireless power system. When the secondary coil of the power receiver is present in the electromagnetic field, the electromagnetic field induces a voltage in the secondary coil. Therefore, the power transmitter can wirelessly transfer power to the power receiver using the inductive coupling between the primary and secondary coils. The power receiver can provide the received power to operate a load. Example loads may include motors, heating elements, electronic devices, or power storage devices, among others. In an example kitchen environment, a magnetic power source, such as a kitchen stove, may include one or more power transmitters.

[0004] Some types of appliances may be constructed for use in wireless power systems, enabling the load to operate using wireless power. Wireless appliances (sometimes referred to as small household appliances, wireless power appliances, or other similar terms) are any devices that include a power receiver and can operate using wireless power received from a power transmitter, including hybrid devices with both wired and wireless power capabilities. For example, wireless appliances (such as wireless blenders, kettles, toasters, or steamers, and other examples) may include both a power receiver and a load. The appliance may be placed on a magnetic power source (or any device with a power transmitter) such that the appliance's power receiver can receive wireless power from the power transmitter. The power receiver in a wireless appliance captures a magnetic field from the power transmitter and converts it into electrical power or uses it for direct induction heating. Summary of the Invention

[0005] The systems, methods, and apparatuses disclosed herein each have several innovative aspects, and no single aspect can explain the desired properties disclosed herein.

[0006] One aspect of this disclosure can be implemented as a power receiver (PRx) used in a wireless power system. The power receiver includes: a PRx slot circuit capable of receiving wireless power from a power transmitter and providing wireless power to a load; a communication unit for communicating with the power transmitter; a controller configured to cooperate with the power transmitter to control the wireless power; and a bias power supply circuit configured to acquire sampled bias power from the PRx slot circuit, the communication unit, or both, and provide the acquired bias power to the controller. Furthermore, the power receiver includes an energy storage unit for providing energy to the bias power supply circuit when the acquired bias power is unavailable or below a level required to operate the controller.

[0007] Another aspect of this disclosure can be implemented as a method for a power receiver. The method includes attempting to obtain sampled bias power from a PRX slot circuit, a communication unit, or both, and providing the sampled bias power to a controller. The method further includes using energy from an energy storage unit when the sampled bias power is unavailable or below a level required to operate the controller.

[0008] Details of one or more embodiments of the subject matter described in this disclosure are set forth in the following drawings and description. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. Attached Figure Description

[0009] Similar reference numerals and symbols indicate similar elements in various accompanying drawings. Note that the dimensions in the drawings may not be drawn to scale.

[0010] Figure 1 A schematic diagram of an example wireless power system is shown.

[0011] Figure 2 This is a block diagram of an example wireless power system.

[0012] Figure 3 The diagram illustrates a state diagram of a wireless power system and an example use case where the power receiver has an integrated energy storage unit.

[0013] Figure 4 The timing diagram illustrates the associated operations of a wireless power system in various states.

[0014] Figure 5A The illustration shows an example power receiver that can operate an impedance-changing circuit using an energy storage unit.

[0015] Figure 5B The diagram illustrates an example impedance variation circuit.

[0016] Figure 6The illustration shows an example power receiver that can operate an open switch using an energy storage unit.

[0017] Figure 7 The illustration shows an example of the power receiver in operation.

[0018] Figure 8 The diagram illustrates a block diagram of an example device used in a wireless power system. Detailed Implementation

[0019] The following description relates to certain embodiments used to describe aspects of the inventiveness of this disclosure. However, those skilled in the art will readily recognize that the teachings herein can be applied in many different ways. The described embodiments can be implemented in any component, apparatus, system, or method for transmitting or receiving wireless power.

[0020] As previously described, a wireless power system includes a power transmitter (PTx) and a power receiver (PRx). The power transmitter may also be referred to as a wireless power transmitting device. The power receiver may also be referred to as a wireless power receiving device. Some examples of this disclosure are based on a kitchen environment. For example, the power transmitter may be part of a magnetic power source, such as a stovetop, countertop, or cooktop. In some embodiments, the power transmitter may include a surface-mounted primary coil, an integrated primary coil, a primary coil mounted on a countertop, or a primary coil embedded or fabricated in a surface on which the power receiver can be placed. The power receiver includes a secondary coil configured to wirelessly receive power via coupling induction to the primary coil of the power transmitter. The power receiver may be part of a wireless appliance, such as a wireless blender, kettle, toaster, or steamer, and other examples. Although the examples of this disclosure refer to wireless power systems in a kitchen environment, the disclosed technology can be used with other types of wireless power systems or in other types of environments.

[0021] Different wireless power standards exist, which may use similar technologies but are designed for different applications. For example, one wireless power standard may support wireless charging of smartphones or other mobile devices; another may support power transfer to wireless kitchen appliances; and yet another may support charging electric vehicles, robots, or drones. Some devices, such as smartphones, operate using batteries that power the processor. In contrast, other devices, such as kitchen appliances, operate using wired power because the load (such as a motor or heating element) may require more power than the battery can actually provide. However, according to this disclosure, the power receiver may include an energy storage unit (such as a small battery) to enhance the wireless power capabilities of the wireless appliance.

[0022] This disclosure provides systems, methods, and apparatus for incorporating an energy storage unit in a wireless device used in a wireless power system. The energy storage unit provides energy to a bias power supply circuit of a power receiver. The bias power supply circuit (sometimes referred to as "bias power supply" for simplicity) provides power harvested from a communication or power carrier. Typically, before wireless power transmission has begun (referred to as a pre-power state), the power receiver obtains bias power by harvesting energy from a communication signal. The bias power is used to operate a controller, a load disconnect switch, a communication unit, or other components in the power receiver besides the load. For example, the bias power is used to close a disconnect switch (thereby connecting the load to the power receiver) before power transmission (referred to as a "power state"). Once wireless power transmission has begun, the bias power is obtained from the wireless power signal.

[0023] Without the technology disclosed herein, a typical mechanism for powering the controller or communication unit of a power receiver is based on bias power acquired from the communication and power signals of the power transmitter. Furthermore, there are scenarios where the power transmitter cannot provide (or the power receiver cannot acquire) sufficient power from the communication circuitry for the power receiver to operate before the power supply state. For example, the power transmitter and power receiver may co-locate for extended periods, leading to timeout conditions. Alternatively, the power receiver may be activated by the controller of the wireless device rather than based on bias power acquired from the communication signals. To address these and other issues, this disclosure provides a technique for integrating an energy storage unit with the power receiver. When bias power is unavailable or insufficient, the energy storage unit can provide energy to operate components of the power receiver, such as controllers, load disconnect switches, impedance changing circuits, communication units, memory, or timers.

[0024] Examples of energy storage units include batteries, supercapacitors, combinations of capacitor banks or storage elements, and others. While the examples in this disclosure are based on electrical energy storage devices, other types of energy storage devices can also be used to generate power, including devices that can generate electrical energy using thermal, mechanical, radiative, or chemical processes. The energy storage unit can be coupled to the bias power supply circuitry of the power receiver such that the energy storage unit provides sufficient power to operate the power receiver in addition to the acquired bias power or when the acquired bias power is unavailable.

[0025] This disclosure provides several example scenarios describing how an energy storage unit can be used in a power receiver. The example scenarios illustrate how existing wireless power protocols or processes can be modified to utilize the integrated energy storage unit. Several example scenarios are based on wireless kitchen appliances that may have unique operational properties compared to other wireless devices, such as smartphones. For example, one scenario describes how a wireless appliance with an integrated energy storage unit can support automatic power-on or restart after being in a standby or off state (referred to as "OFF"). In some implementations, the wireless appliance can automatically power on or restart without user interaction, or based on earlier user actions (such as setting a timer or a predetermined power-on time).

[0026] In some implementations, the power receiver uses energy from the energy storage unit to automatically power on or restart the power transmitter after it has been in standby mode. The power receiver may use an impedance changing circuit, which is at least partially powered by the energy storage unit, to wake the power transmitter from standby mode. The impedance changing circuit may also be referred to as a wake-up circuit, impedance circuit, impedance load switch, impedance change toggle, or other terms. The impedance changing circuit can be any type of circuit that the power receiver can temporarily activate to allow the power transmitter to detect an impedance change. When the power receiver makes a change to the impedance changing circuit (such as a toggle switch), the power transmitter detects a change reflecting the impedance, which wakes the power transmitter from standby mode. Therefore, the process of activating the impedance changing circuit may also be referred to as a wake-up signal.

[0027] In scenarios where a power interruption has occurred (such as a mains power failure or outage), the wireless appliance can use the energy storage unit to power volatile memory. This power interruption can be referred to as a wireless power interruption. In another scenario, before switching off (such as after a cooking operation or a power interruption), the wireless appliance can use the energy storage unit to store information (such as cooking status, timer status, temperature, or other parameters) in non-volatile memory. Therefore, the wireless appliance can maintain state information about the cooking process or wireless power configuration. When mains power is restored, the power transmitter and receiver can resume power transmission using the previously negotiated wireless power configuration. Furthermore, the wireless appliance can resume the cooking operation or timer program. In yet another example scenario, during the transition from a pre-powered state to a powered state, the energy storage unit enables the power receiver to close and maintain an off switch. The acquired bias power may be insufficient to reliably close and maintain the off switch, resulting in switch bounce or failure. The energy storage unit can supply or increase the bias power required to close the off switch until the bias power can be obtained from the wireless power signal.

[0028] Specific embodiments of the subject matter described in this disclosure can be implemented to achieve one or more of the following potential advantages: Wireless appliances can recover from power interruptions that would otherwise disrupt cooking, heating, or kitchen processes. Wireless appliances can improve reliability and functionality by combining energy storage units with wireless power protocols. Wireless appliances can reflect the user experience that users might expect from wired kitchen appliances, while providing the convenience offered by wireless power.

[0029] Figure 1 A schematic diagram of an example wireless power transmission system 100 is shown. The wireless power transmission system may include a power transmitter 102 and a power receiver 104. The power transmitter 102 includes a primary coil 106. When the primary coil 106 transmits wireless power 108, it generates a magnetic field that induces a voltage in the secondary coil 110 of the power receiver 104. The power receiver 104 may include a secondary coil 110 configured to receive wireless power 108. (Refer to...) Figure 2 The components of the power transmitter 102 and the power receiver 104 are described in further detail.

[0030] For the purpose of comparison, Figure 1 A conventional wired appliance 112 operating using a wired power source 114 is also shown. The goal of kitchen wireless power technology is to provide the same or better user experience in wireless appliances as users would expect from wired appliances 112. Instead of a wired power source 114 (or attached to one), the wireless appliance includes a power receiver 104 capable of receiving wireless power from a power transmitter 102. The power receiver 104 may be included in the appliance (such as a wireless kitchen appliance and others) and is intended to operate on a wireless power transmitting surface (such as a kitchen countertop, stovetop, or cooktop) configured with one or more primary coils. Figure 1 Examples 116a, 116b of appliances that can utilize the power transmitter 102 are shown. For example, the appliance could be a kettle (as illustrated). Other examples of appliances that may include a power receiver could include a slow cooker, blender, cookware, rice cooker, coffee maker, toaster, baking appliance, frying pan, electric griddle, any type of appliance configured to heat liquids or process food, and many others. In one example 116a, the wireless appliance has both wired and wireless power capabilities and may be referred to as a hybrid appliance. In another example 116b, the wireless appliance does not include wired power capability and operates using only wireless power.

[0031] In a kitchen environment, the power transmitter 102 may be included in a kitchen appliance, such as a cooktop or stovetop. For example, in some embodiments, the stovetop may include several locations for placing items. At least one of these locations may include the power transmitter 102, which supports wireless power transmission to an appliance including a power receiver 104. In some embodiments, the power transmitter 102 may be integrated into a portable stovetop. For example, a portable stovetop may include a battery or be capable of powering the power transmitter 102 with an external power source, or it may be suitable for camping.

[0032] Some appliances operate based on user interaction to control ON and OFF operation. For example, some blenders or juicers may be designed with buttons or other user interfaces for manual control to turn the appliance ON when the user intends to use it. This ensures that no power is wasted and that the appliance only operates when turned ON by the user. Other appliances may be designed to automatically turn ON or OFF to reduce user interaction. For example, appliances such as rice cookers, kettles, and coffee makers may be designed to automatically turn ON or OFF to heat food or liquid contents according to a schedule or temperature standard. For example, the appliance may be configured to automatically turn ON and automatically turn OFF based on a predetermined on time, or enter a "keep warm" process once the heating operation is complete. In one example, a user may place a wireless appliance (such as a kettle or coffee maker) on a power transmitter and set a predetermined on time. In some implementations, an integrated energy storage unit can enable the wireless appliance to have sufficient bias power to sustain timers or operations configured for a scheduled controller. Alternatively or additionally, the energy storage unit enables wireless devices to recover from power interruptions and continue desired operation.

[0033] Figure 2This is a block diagram of an example wireless power system 200. The example wireless power system 200 includes a power transmitter 102 and a power receiver 104. The power transmitter 102 includes a primary coil 106 and a PTx controller 210. The primary coil 106 may be associated with a power transmitter circuit 206 (sometimes also referred to as a power signal generator, drive circuit, or driver). The primary coil 106 may be a wire coil that transmits wireless power (which may also be referred to as wireless energy). The primary coil 106 may use an induced or resonant magnetic field to transmit wireless energy. The power transmitter circuit 206 may include components (not shown) for preparing wireless power. For example, the power transmitter circuit 206 may include one or more switches, drivers, series capacitors, rectifiers, inverters, or other components. In some embodiments, the power transmitter circuit 206 includes an inverter and a PTx resonant tank circuit. The PTx controller 210 may be implemented as a microcontroller, a dedicated processor, an integrated circuit, an application-specific integrated circuit (ASIC), or any other suitable electronic device.

[0034] Power supply 204 provides power to power transmitter unit 208. In some embodiments, power supply 204 can convert alternating current (AC) power to direct current (DC) power. For example, power supply 204 may include a converter that receives AC power from an external power supply and converts the AC power into DC power used by power transmitter circuit 206. Alternatively or additionally, components of power transmitter circuit 206 (such as an inverter) can convert DC power to AC power. Power supply 204 may be integrated into power transmitter 102 or may be external to power transmitter 102. In some embodiments, power transmitter 102 causes power supply 204 to regulate the DC output voltage of power supply 204. For example, PTx controller 210 may set the DC voltage of power supply 204 based on information received from power receiver 104, such as a value indicating the requested power. Power transmitter 102 may receive power configuration information from power receiver 104 and use this information to set parameters such as the DC output voltage of power supply 204. The power transmitter 102 can receive power configuration information during various operating states, such as a discovery state or a power state. In some embodiments, the power transmitter 102 includes a DC-DC converter (not shown) between the power supply 204 and the power transmitter circuit 206 to control a variable DC output voltage.

[0035] PTx controller 210 is connected to communication interface 212. Communication interface 212 is connected to first communication coil 214. In some embodiments, communication interface 212 and first communication coil 214 may be collectively referred to as a first communication unit. In some embodiments, the first communication unit may support short-range radio frequency communication, such as Near Field Communication (NFC) or Bluetooth (BT). NFC is a technology for data transmission via a carrier frequency of 13.56 MHz. The first communication unit may also support any suitable communication protocol. The first communication unit may include modulation and demodulation circuitry for wireless communication via first communication coil 214. Alternatively or additionally, PTx controller 210 may use frequency, amplitude, current, or voltage modulation of a wireless power signal to communicate via an in-band communication link (not shown) including primary coil 106.

[0036] exist Figure 2In the example, wireless device 202 includes a power receiver 104 and a load 224. Power receiver 104 may include a secondary coil 110, a PRx slot circuit 236, a rectifier 220, a PRx controller 222, a communication interface 226, and a memory (not shown). In some embodiments, wireless device 202 also includes a load controller 230 and a user interface 252 (such as a button, switch, touchpad, indicator light, touchscreen, or wireless LAN interface). In some embodiments, load 224 may include a driver (not shown) for controlling at least one parameter, such as the charging current, speed, or torque of the load. In some embodiments, rectifier 220 may be omitted, for example, when the voltage induced in secondary coil 110 can directly power load 224. PRx slot circuit 236 may include a capacitor or other components that enable secondary coil 110 to receive wireless power 108 during power-on states. Although not shown, small capacitors may be used before rectifier 220 and load capacitors may be used after rectifier 220 to match impedance and filter high-frequency components of the rectifier voltage. Although shown as different components, some components may also be packaged or implemented in the same hardware. For example, in some embodiments, PRx controller 222 and load controller 230 may be implemented as a single controller. PRx controller 222, load controller 230, communication interface 226, or any combination thereof may be implemented as a microcontroller, dedicated processor, integrated circuit, application-specific integrated circuit (ASIC), or any other suitable electronic device. Communication interface 226 and second communication coil 228 may be collectively referred to as the second communication unit. The second communication unit may also include a power harvester (not shown) that harvests energy from the communication signal and provides the harvested bias power to bias power supply circuit 234 (arrow 244). Bias power supply circuit 234 provides power to PRx controller 222 (shown at arrow 250) and load controller 230 (shown at arrow 248).

[0037] The PTx controller 210 can detect the presence or proximity of the power receiver 104. This detection can occur during a periodic verification process of the communication interface 212. During the verification process, when the power receiver 104 approaches the power transmitter 102, the communication interface 212 supplies power to the communication interface 226 via a communication signal 254. The communication interface 226 can use a bias power supply circuit 234 to "wake up" and power the PTx controller 222. The communication interface 226 can transmit a reply signal back to the communication interface 212 to confirm that it is a power receiver. A handshake process can occur before power transmission, while the PTx controller 210 can receive identification and configuration data and other information from the power receiver 104. The PTx controller 210 can control the characteristics of the wireless power it provides to the power receiver 104 based on the configuration data.

[0038] PRx controller 222 is operatively coupled to rectifier 220 and communication interface 226. Communication interface 226 may include modulation and demodulation circuitry for wireless communication via a second communication coil 228. Therefore, PRx controller 222 can wirelessly transmit feedback information to PTx controller 210 via communication interface 226, or to communication interface 212 using short-range radio frequency communication (such as NFC). Alternatively or additionally, PRx controller 222 may use load modulation to communicate via an in-band communication link (not shown) including secondary coil 110.

[0039] The load controller 230 can be operatively coupled to the load 224 and the PRx controller 222 (or to the communication interface 226). Figure 2 (Coupling not shown). Load controller 230 can detect changes in load state. Load controller 230 can also determine a load voltage reference and / or the load's power requirement. Load controller 230 can also transmit the load voltage reference, load current, load power requirement, and any other suitable information to PRx controller 222 or communication interface 226 for communication with power transmitter 102. During power states, PRx controller 222 can additionally determine and provide one or more feedback messages indicating the measured load voltage, load current, load power requirement, and available power for load 224. In some feedback messages, the feedback information may include a reference voltage indicating the voltage required by load 224. In some feedback messages, the feedback information may indicate an error in the output voltage of load 224. In some feedback messages, the feedback information may include the power required by the load. Although PRx controller 222 and load controller 230 are shown separately, they may also be included in the same components of power receiver 104.

[0040] Some appliances are equipped with safety features that operate in conjunction with the operating state, such as disconnect switch 232. For example, when power receiver 104 is in a pre-powered state (as shown in reference...) Figure 3 In the described standby, discovery, and connected states, disconnect switch 232 may remain in the open position to prevent current from flowing to load 224. Before transitioning to the power-on state, PRx controller 222 may move disconnect switch 232 to the closed position to allow current to flow to load 224. In emergency situations (such as overvoltage or overcurrent), PRx controller 222 may open disconnect switch 232 to prevent damage to load 224 or other components of power receiver 104.

[0041] After disconnect switch 232 is closed, PRx controller 222 may communicate a message to PTx controller 210 to transition the wireless power system to a powered state. Alternatively or additionally, PRx controller 222 may communicate a power request to initiate the transmission of wireless power 108. Once wireless power 108 is received by power receiver 104, bias power supply circuit 234 may use either the bias power acquired from PRx slot circuit 236 (arrow 242) or the voltage at load 224. Alternatively or additionally, some types of load 224 may supply power (arrow 246) to bias power supply circuit 234. In addition to supplying power to PRx controller 222 and load controller 230, bias power supply circuit 234 supplies power (arrow 240) to maintain disconnect switch 232 in the closed position during normal operation in the powered state.

[0042] According to this disclosure, the wireless device 202 includes an energy storage unit 238. Although the energy storage unit 238 is illustrated as part of the power receiver 104, it may also be co-located with the power receiver 104 as another component of the wireless device 202. The energy storage unit 238 can supply power (arrow 256) to a bias power supply circuit 234. In some embodiments, the bias power supply circuit 234 can supply power (arrow 258) to the energy storage unit 238 when it receives sufficient acquired bias power from the communication signal 254 or the wireless power 108. For example, the energy storage unit 238 may be a rechargeable battery. In some embodiments, the energy storage unit 238 may be a small battery, such as a coin cell. In some embodiments, the energy storage unit 238 can be charged by using a temporary connection to an external power supply or by using other electrical or mechanical charging methods, including some techniques involving user actions to generate or connect energy for the energy storage unit 238.

[0043] When the acquired bias power is unavailable, the energy storage unit 238 supplies power to the bias power supply circuit 234. Acquired bias power is considered unavailable when there is no acquired bias power or when the amount of acquired bias power is insufficient to operate the controller or load disconnect switch. For example, acquired bias power may be unavailable if the power transmitter 102 experiences a power interruption or if the communication signal 254 stops due to a timeout condition.

[0044] Figure 3 The diagram illustrates a state diagram 300 of a wireless power system and an example use case where the power receiver has an integrated energy storage unit. State diagram 300 illustrates the operational states in which the wireless power system can operate. When the power receiver is placed within the operational capacity of the interface surface of the power transmitter, the two initiate communication for the purpose of configuring and controlling power transmission. Figure 3 The four operating states are shown: Standby state 302 (sometimes also called the verification phase); Discovery state 304 (sometimes also called the identification phase); Connection state 306; and Power state 308 (sometimes also called the power transmission phase). Standby state 302, Discovery state 304, and Connection state 306 can be collectively referred to as the pre-power state. Technical specifications can define how the power transmitter and power receiver can transition between operating states. For example, a wireless power system typically begins in Standby state 302 until the power transmitter detects the power receiver, thus moving the standby state to Discovery state 304. In Discovery state 304, the power transmitter establishes communication and receives initial identification information and static configuration data from the power receiver. In Connection state 306, the power transmitter and power receiver exchange information to agree on and adjust parameters related to wireless power transmission. In Power state 308, the power transmitter transmits wireless power to the power receiver. During Power state 308, the power receiver may occasionally or periodically communicate status or feedback control messages to the power transmitter. The system can move to a reinitialization state (not shown) as needed to reinitialize or return to standby when communication, power supply, or other activities cease. Each of these operating states is briefly described in this document for reference.

[0045] In standby state 302, the power transmitter attempts to establish communication with the power receiver. The power receiver may simply be placed on the interface surface, or it may not be present during this operating state. The power transmitter may attempt to communicate or detect the presence of the power receiver. For example, the power transmitter may use analog verification, out-of-band communication (such as NFC), digital verification, impedance change detection, or any combination thereof to determine the presence of a compatible power receiver. Once the wireless power system determines that the power receiver is present (e.g., through acknowledgment of NFC communication), the wireless power system can transition to discovery state 304.

[0046] In discovery state 304, the power receiver can establish communication with the power transmitter and transmit static configuration information (such as identification and configuration information) to the power transmitter. For example, the power transmitter can retrieve static configuration information from the power receiver via NFC communication. The power transmitter and power receiver can use this information to verify whether they both use a compatible version of the technical specifications or protocol for wireless power transmission. The power transmitter and power receiver can communicate basic settings or information about their respective capabilities. The wireless power system can then transition from discovery state 304 to connected state 306.

[0047] In connection state 306, the power transmitter and power receiver can further exchange communications to negotiate parameters for managing the power state. For example, power negotiation may occur during connection state 306. After negotiating the parameters, the power transmitter can be ready to transmit wireless power, and the power receiver can be ready to receive wireless power. Before transitioning to power state 308, the power transmitter can wait for a request or command from the power receiver. This can be useful, for example, when a wireless appliance (such as a blender, toaster, mixer, or microwave oven) is configured to wait for user interaction before use. The user can initiate power state 308 through the power receiver's user interface (such as an activation switch), which is then communicated to the power transmitter to transition to power state 308.

[0048] The power transmitter and power receiver can transition from power state 308 back to connected state 306 until the next power transfer operation is required. Alternatively, the wireless power system may transition to standby state 302. In some implementations, if the power transmitter determines that the power receiver has moved, is no longer present in the power transmitter's operating environment, or has sensed a foreign object during conditional standby, the power transmitter may transition to a reinitialization state (not shown) to reset or clear the previous configuration of the previously existing power receiver.

[0049] Some operations, such as item detection and communication handshake, are time-sensitive. For example, the transition from standby state 302 to discovery state 304 is based on item detection. Power transmitters typically detect power receivers based on impedance changes. Power transmitters can use their primary coil, communication coil, detection coil, or any other type of detection circuitry to detect impedance changes reflected by items in the operating environment. In some implementations, the power transmitter may measure voltage and / or current in the communication circuitry or PTx slot circuitry (e.g., the primary coil) and monitor for changes exceeding a threshold amount (e.g., a 10% change in the measurement). Because impedance change processes are based on variations, the power transmitter typically detects the power receiver when it is first placed in the operating environment. However, if the power receiver remains there for an extended period (or after a power outage / shutdown, restart), the power transmitter may time out and move to standby state 302. The power receiver cannot keep the power transmitter in discovery state 304 (or connected state 306) indefinitely. In some cases, the power transmitter may determine that the power receiver is faulty or unresponsive. As shown at arrow 310, the wireless power system may move to standby state 302 due to a timeout condition, in which the power receiver has been in the operating environment for an extended period. The power transmitter may implement a time limit after which it will return to standby state 302. The time limit may be based on energy conservation or safety considerations. Another scenario in which the power transmitter may return to standby state 302 is a power interruption (power outage) or power decay (power failure) that would cause the power transmitter to reset. Regardless of the cause, the power transmitter may return to standby state (box 310) while the power receiver remains close to the power transmitter.

[0050] Once the power transmitter is in standby mode, without the technology disclosed herein, it might remain in standby mode until user operation (such as removing and placing an appliance, or making input on the user interface of the power transmitter or receiver). When the power transmitter returns to standby mode 302 and the power receiver remains on the interface surface, the power transmitter may not detect impedance changes that would typically occur when the power receiver is initially placed on the interface surface. In a kitchen environment, a user might place a wireless appliance on the power transmitter and leave it there for extended periods or indefinitely. Requiring user action might be impractical or detract from the user experience.

[0051] Some appliances may be designed to automatically switch on or off based on a schedule or temperature standard. For example, an appliance may receive wireless power to perform heating operations (such as cooking food or boiling liquids). In some cases, it is desirable for the appliance to automatically switch on at a certain time to perform heating operations according to the end-user's schedule. In other cases, it is desirable for the appliance to automatically switch on during cooking time, heating, or reheating operations, or to maintain a target temperature. Alternatively or additionally, wireless appliances may have wireless internet connectivity or remote applications that can be remotely triggered to activate the appliance.

[0052] Current technology for managing the automatic ON and OFF operation of appliances is based on control messages from the appliance to the power transmitter. For example, an appliance may remain in a connected state 306 of operation when it does not receive wireless power for heating or reheating operation. In connected state 306, the appliance consumes power from the power transmitter to maintain periodic communication, controller manipulation, and sensor measurements. Therefore, the appliance will continue to consume power during the OFF phase of operation. In some implementations, during the OFF phase of operation, the appliance uses bias power acquired from NFC signals from the communication interface of the power transmitter to maintain connected state 306 and sensor measurements. Therefore, the appliance relies on power acquired from the NFC of the power transmitter. As previously mentioned, the power transmitter may move to a standby state after a threshold period of inactivity. If the power transmitter keeps the NFC field active, the power receiver may continue to acquire power even during inactivity, resulting in inefficiency and unnecessary power consumption. In some cases, power consumption may violate standby power requirements stipulated by regulatory agencies. To reduce power consumption, the power transmitter may return to standby state 302 and may need to disconnect the NFC field. This prevents the power receiver from acquiring the bias power to maintain a timer or controller that implements automatic ON or remote turn-on, unless the power receiver has another power source (such as an energy storage unit provided by this disclosure).

[0053] After describing state diagram 300 and the example problem, Figure 3 Example scenarios using an energy storage unit in a power receiver to address some of the aforementioned problems are also illustrated. In a first example (box 310), the energy storage unit can power a controller in response to activation (such as automatic ON, restart after power interruption, remote activation via wireless communication, etc.). When the controller determines to activate the wireless device, the energy storage unit and impedance changing circuitry (such as reference circuitry)... Figure 5A and Figure 5BThe power transmitter (as described) can be woken up from standby state 302. For example, the power receiver can use power from the energy storage unit to make a change at the power receiver, causing the power transmitter to detect the impedance change. The impedance change at the power transmitter wakes it up and allows it to continue item detection and transition to discovery state 304. The power receiver activating the impedance change circuitry is an example of a wake-up signal. Alternatively or additionally, the power receiver can send a radio frequency (RF) transmission (such as a communication or RF signal) to wake up the power transmitter.

[0054] In another example (box 330), the energy storage unit may provide power to the power receiver to maintain appliance status, such as configuration or cooking information. During a power interruption or power decay, the power transmitter may reset and restart state diagram 300, from standby state 302 to connected state 306, and then return to the active power state 308 before the power interruption. This can lead to a poor user experience, disrupt the cooking process, or even pose a danger of overheating in some cases. Using the power from the energy storage unit, the power receiver can maintain information about the cooking status. In some implementations, the cooking information may be stored in volatile memory that can be maintained using the power from the energy storage unit. When power transmission is restored, the power receiver (such as a load controller or PTx controller) can continue the cooking schedule. Without the technology disclosed herein, the power receiver might restart the entire cooking process again (potentially overcooking food or liquids) or not start cooking at all (potentially no cooking or delayed cooking).

[0055] In addition to maintaining information about the cooking state, the energy storage unit and memory can store configuration information, such as negotiated power settings or other configuration settings exchanged during discovery state 304 and connection state 306, prior to a power interruption. When power is restored, the power receiver can use the previously negotiated configuration (such as previously negotiated values ​​stored in memory) to quickly complete the negotiation process with the power transmitter and move to the power state. In some cases, the power transmitter also has stored configuration information or can accept parameters from the power receiver, such that discovery state 304 and / or connection state 306 can be omitted or skipped when the wireless power system is recovering from a power interruption. In some implementations, if the power transmitter determines that the power receiver is present in the operating environment and there is no foreign object during the foreign object detection (FOD) process, the power transmitter may omit the operation of discovery state 304 or connection state 306, which would otherwise be performed when the power receiver is first placed on the power transmitter. For example, the power transmitter may determine that the power receiver is the same as one previously detected before the interruption based on a matching device identification or other marker. The power transmitter may omit authentication, one or more configuration messages or power negotiation message exchanges, and other examples.

[0056] In the third example (box 340), the energy storage unit provides sufficient power to close the disconnect switch before the power receiver transitions to power state 308. As previously mentioned, the disconnect switch typically uses bias power to close. In some cases, the acquired bias power is less than the power required to reliably close the disconnect switch. Closing the disconnect switch may require sufficient power (e.g., 100 mW to 250 mW for a relay-type switch). The acquired bias power may be insufficient to close or hold the switch closed for various reasons. For example, if there is a large displacement between the power transmitter and the power receiver, there will be inefficient coupling that fails to transmit sufficient power. Different NFC coil sizes can lead to poor coupling. A large Z-distance can also lead to poor coupling. If the acquired bias power is insufficient to reliably close and hold the disconnect switch closed, the disconnect switch may fail, repeatedly open / close, or simply fail to close at all. Failure to hold the switch closed during power state can cause the load to disconnect and expose the power transmitter to dangerously high current. This can also cause arcing of the switch contacts in relay-type switches, leading to contact wear and tear or permanent melting of the switch contacts. The energy storage unit enables the power receiver to reliably close the open switch before power state 308, and also operates the controller to mitigate problems that may arise before or during power state 308 due to insufficient acquired bias power.

[0057] Figure 4 The timing diagram 400 illustrates the associated operations of a wireless power system in various states. Timing diagram 400 describes the operation of power receiver 104 (PRx) and power transmitter 102 (PTx). Although described as the operation of power receiver 104 and power transmitter 102, it should be understood that these operations may be performed by the PTx controller and PRx controller, respectively. Power receiver 104 and power transmitter 102 can follow state diagrams for various operating states, as shown in the reference diagram. Figure 3 As described. Figure 4 The status of communication channel 406 (NFC) in relation to the described operation is also shown.

[0058] For the sake of brevity, Figure 4The initial instances of standby state 302, discovery state 304, and connected state 306 are briefly described in detail. During standby state 302, a user can place an appliance with a power receiver 104 into the interface space of the power transmitter 102. The power transmitter 102 may send a detection signal 402 and detect the power receiver 104. For example, the power transmitter 102 may detect the power receiver 104 based on an impedance change 404 caused when the power receiver 104 enters the magnetic field of the detection signal 402. Due to the impedance change 404, the power transmitter 102 detects the power receiver 104 and enters discovery state 304. Discovery state 304 may include one or more discovery state messages 408a, 408b (such as identification and configuration messages and / or NFC data exchange format (NDEF) messages) and state transition request messages. The “NEXT” message is a state transition request message that indicates a request to transition to another state and the requested state (e.g., the “NEXT / con” message is a state transition request message to transition to the connected state). The recipient of a state transition request message can respond with a response message (“RESP / ok”). The “RESP” message may indicate yes (“ok”), no (“nok”), undefined (“nd”), or busy (“bsy”). In some implementations, the “RESP” message is a response that may indicate acknowledgement (“ack”), unacknowledgement (“nak”), or undefined (“nd”).

[0059] For the sake of brevity, Figure 4 Details of connection state 306 are omitted. Connection state 306 may include one or more connection state messages 410a (such as power negotiation messages). Additionally, power transmitter 102 may perform a FOD process during connection state 306 to determine the absence of foreign objects. At some point, power receiver 104 sends a power request message 414 to initiate power transfer in power state 308. During power state 308, power transmitter 102 transmits a radio power signal 416 to power receiver 104. On communication channel 406, communication 412 may occur during the pre-power state. Although shown as continuous communication 412, communication 412 may include inactive phases, such as during FOD or pre-power coupling factor measurement phases. During the power phase, communication channel 406 may use communication slots 418a, 418b at zero-crossing events of the radio power signal 416. Not all zero-crossing events may be used for inserting communication slots.

[0060] exist Figure 4In the example, power state 308 is disturbed for various reasons. For simplicity, the disturbance is shown as undefined state 424. For example, when the initial heating operation is complete, power receiver 104 may convey a message to transition to connected or standby state 422. Alternatively, if power receiver 104 remains in connected state 306 for too long, power transmitter 102 may return to standby state 422 due to timeout. In another example, a power disturbance (power outage or failure) may cause power transmitter 102 to reset and enter standby state 422. In yet another example, power receiver 104 may be programmed to have automatic or remote power-on capability, allowing it to be activated after an idle phase.

[0061] At some point after being in the undefined state 424, the power receiver 104 detects device activation 430. Device activation 430 may be a button or input via a user interface. Alternatively, device activation 430 may be a signal from a PTx controller (powered by the energy storage unit) to automatically turn on or restart the power receiver 104 after a power interruption or inactivity phase. In yet another example, device activation 430 may be a message received via a wireless internet connection (also powered by the energy storage unit), allowing a user or server to remotely activate the power receiver 104 using the message. Based on device activation 430, the power receiver 104 may trigger a wake-up signal to wake up the power transmitter 102. This disclosure includes several example implementations of the wake-up signal, including some example implementations based on causing the power transmitter 102 to detect an impedance change 432.

[0062] In an example (such as) Figure 4 In the example shown), the wake-up signal is based on PRx through an activation impedance change circuit (such as reference circuit). Figure 5A and Figure 5B The impedance change 432 caused by the described impedance change. The energy storage unit 238 can supply power to the impedance change circuit to make a change that will cause the power transmitter 102 to detect the impedance change 432. In another example (not shown), the power receiver 104 can use the power from the energy storage unit 238 to send a wake-up signal in the form of a radio frequency transmission. In yet another example, the wake-up signal can be any transmission or circuit change that will cause the power transmitter 102 to detect the impedance change 432 in a manner that alters the magnetic field of the power transmitter 102. In some embodiments, the wake-up signal is a process that utilizes the item detection mechanism of the power transmitter 102 to cause the power transmitter 102 to detect the power receiver 104 and / or any process that transitions from an undefined state 424 to a pre-powered state 420.

[0063] After the power transmitter wakes up, the power transmitter 102 and the power receiver 104 can resume one of the pre-power states 420 (such as discovery state 304 or connection state 306). In some embodiments, the power transmitter 102 may omit or skip the discovery message and continue with connection state messages 410c, 410d to resume power transmission based on the previous configuration.

[0064] In some implementations, power transmitter 102 and power receiver 104 may perform one or more pre-power operations associated with pre-power state 420, such as a discovery state or a connected state. The power transmitter may verify that the appliance on the interface surface is the same as the appliance left before the undefined state 424. For example, the power transmitter may compare appliance identification (ID) information with previous appliance ID information stored before the conditional standby state. If a new appliance is detected (meaning the appliance ID information is different from the appliance ID information before the conditional standby state), the power transmitter will start with the new appliance in a completely new discovery and connected state. Otherwise, if the same appliance is present, the power transmitter 102 may continue the pre-power operation. In some implementations, the pre-power operation may include a FOD process to determine that no foreign object was introduced during the undefined state 424. The power transmitter may also verify that the appliance alignment on the interface surface is within an acceptable range of movement that the appliance might have made during the sleep time undefined state 424. In some implementations, the pre-power operation may omit one or more operations that would generally have occurred during the first instance of the pre-power state.

[0065] Figure 5A The illustration shows an example power receiver 500 capable of operating an impedance-changing circuit using an energy storage unit. The example power receiver 500 can be used as a reference. Figures 1 to 4 An example of the described power receiver 104. Power receiver 500 may be included in an appliance. Power receiver 500 may include a load 224, or the load 224 may be a component of an appliance that also includes power receiver 500. Power receiver 500 includes a secondary coil 110, a second communication coil 228, a communication interface 226, and a PRx controller 222, as shown in the reference. Figure 2 As described. In some embodiments, the power receiver 500 may include a rectifier, or may not include a rectifier. Figure 2 (Not shown in the image). Figure 5AAn example PRx slot circuit 236 is also shown, which includes a series capacitor 502 coupled to one or more branches of the secondary coil 110. Alternatively or additionally, the PRx slot circuit 236 includes a parallel capacitor 504 coupled between multiple branches of the secondary coil 110. An example power receiver 500 includes a disconnect switch 232 connected in series between one branch of the secondary coil 110 and a load 224. Although the disconnect switch 232 is shown as being connected in series with the series capacitor 502, other configurations are possible. The power receiver 500 also includes a bias supply circuit 234 and an energy storage unit 238, as shown in reference. Figure 2 As described.

[0066] Figure 5A Two example impedance changing circuits 510a and 510b are shown. In one example, impedance changing circuit 510a is located in secondary coil 110 or PRx slot circuit 236. In another example, impedance changing circuit 510b is located in second communication coil 228. In other examples (not shown), the impedance changing circuit may be a separate circuit not coupled to either the power receiving unit or the communication unit. The impedance changing circuit may be any circuit that uses power from energy storage unit 238 (possibly via bias power supply circuit 234) to simulate impedance changes or otherwise generate conditions for waking up the power transmitter (not shown).

[0067] Figure 5B The illustration shows an example impedance changing circuit 526. Example impedance changing circuit 526 is based on... Figure 5A The impedance changing circuits 510a and 510b shown may be used; and may be implemented as a first example impedance changing circuit 510a (located at the secondary coil) or a second example impedance changing circuit 510b (located at the communication coil). The impedance changing circuit 526 may include a load component 520, a switching component 522 (e.g., shown as a transistor), or both. The switching component 522 may be implemented using a silicon switch, a metal-oxide-semiconductor field-effect transistor (MOSFET) switch, an electromechanical switch, or the like. The load component 520 may be any type of load, such as a resistor, capacitor, diode, lighting component, mechanical load, or any combination of these components. Figure 5B In the example shown, the PRx controller 222 transmits a signal 524 to activate power from the energy storage unit 238 (possibly via bias power supply circuit 234) to be applied to the switching element 522. The power from the energy storage unit 238 is shown as an input (512a or 512b) to the switching element 522 to simulate an impedance change. In some embodiments, the PRx controller 222 may transmit signals (such as inputs 512a or 512b) directly to the impedance change circuit 526 (510a or 510b).

[0068] Figure 6 An example power receiver 600 capable of operating an open switch using an energy storage unit is illustrated. The example power receiver 600 may be an example of the power receiver 104 described with reference to any of the accompanying drawings of this disclosure. The power receiver 600 includes a secondary coil 110, a second communication coil 228, a communication interface 226, a PRx controller 222, a load 224, a PRx slot circuit 236, a bias power supply circuit 234, and an energy storage unit 238, as shown in reference to… Figure 2 As described. In order to close the disconnect switch 232 before entering the power state and to keep it closed throughout the power state, the PRx controller 222 transmits a control signal 604 to activate the switching power supply 602 to close the disconnect switch 232. The switching power supply 602 may be connected via a bias power supply circuit 234 (such as...). Figure 6 (As shown) Power comes from energy storage unit 238 or directly from energy storage unit 238. Alternatively, after PRx controller 222 obtains power from energy storage unit 238 and bias power supply circuit 234, switching power supply 602 may be powered by PRx controller 222. Energy storage unit 238 may be designed to ensure that disconnect switch 232 will not open as long as control signal 604 is provided for the closing of disconnect switch 232, even when power receiver 600 does not have sufficient energy harvesting for various reasons.

[0069] Figure 7 The illustration shows an example operation 700 of the power receiver. In block 702, the power receiver attempts to obtain sampled bias power from the PRx slot circuitry, the communication unit, or both, and provides the sampled bias power to the controller. In block 704, when the sampled bias power is unavailable or below the level required to operate the controller, the power receiver uses energy from the energy storage unit.

[0070] In some implementations, the power receiver uses energy from the energy storage unit to generate a wake-up signal via an impedance change circuit. In some implementations, the wake-up signal is designed to utilize the power transmitter's object detection mechanism to wake the power transmitter by causing it to detect an impedance change. The power receiver may generate the wake-up signal based on user interface commands, a programmed schedule, or a message received via a network interface. The impedance change circuit may be integrated with or coupled to a secondary coil of the PRx slot circuit, an antenna of the communication unit, or a separate circuit.

[0071] In some implementations, the energy storage unit provides sufficient energy to the memory element to maintain the volatile memory state of the memory element after a power interruption until the power transmitter and power receiver resume wireless power transmission.

[0072] In some implementations, when the acquired bias power is unavailable, the energy storage unit supplies power to the controller so that the controller can maintain the load schedule.

[0073] In some implementations, when the acquired bias power is unavailable (or insufficient), the power receiver uses energy from the energy storage unit to close and maintain the open switch of the PRx slot circuit based on a control signal from the controller.

[0074] In some implementations, when the acquired bias power is not available to power the network interface of the power receiver, the power receiver uses energy from the energy storage unit to power the network interface.

[0075] Figure 8 A block diagram of an example device used in a wireless power system is illustrated. In some embodiments, device 800 may be a wireless power transmitting device (such as power transmitter 102) described herein. Device 800 may include processor 802 (which may include multiple processors, multiple cores, multiple nodes, or implement multithreading, etc.). Device 800 may also include memory 804. Memory 804 may be any one or more possible implementations of system memory or computer-readable media described herein. Device 800 may also include bus 806 (such as PCI, ISA, PCI-Express, HyperTransport®, InfiniBand®, NuBus, ®AHB, AXI, etc.).

[0076] Device 800 may include one or more controllers 808 (such as a PTx controller). In some embodiments, controller 808 may be distributed within processor 802, memory 804, and bus 806. Controller 808 may perform some or all of the operations described herein. For example, controller 808 may perform the operations described herein. Figures 1 to 7 The process described by any one of them or any combination thereof.

[0077] The memory 804 may include computer instructions executable by the processor 802 to implement the functions of the embodiments described herein. Any of these functions may be implemented partially (or wholly) in hardware or on the processor 802. For example, the functions may be implemented using an application-specific integrated circuit, logic components implemented in the processor 802, peripheral devices, or coprocessors on a card. Furthermore, the implementation may include… Figure 8 Fewer or additional components not shown. Processor 802, memory 804, and controller 808 may be coupled to bus 806. Although memory 804 is shown coupled to bus 806, it may be coupled to processor 802 or controller 808.

[0078] The device 800 also includes an energy storage unit 810. The energy storage unit 810 may implement reference... Figures 1 to 7 Any of the operations described. For example, energy storage unit 810 may process a request message from a power receiver requesting to enter a conditional standby state. Energy storage unit 810 may implement a timer or counter to determine when a sleep timeout occurs. Energy storage unit 810 may initiate one or more operations to wake up the power receiver after the sleep timeout.

[0079] Figures 1 to 8 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 the claims. Some implementations may perform additional operations, fewer operations, parallel operations, or operations in a different order, as well as perform some operations in different ways.

[0080] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations can be made based on the foregoing disclosure, or modifications and variations can be obtained based on practice of the aspects. While aspects of this disclosure have been described in various exemplary forms, any combination of aspects in any example is also covered within the scope of this disclosure. The examples in this disclosure are provided for educational purposes. Alternatively, or in addition to other examples described herein, the examples also include any combination of the following implementation options (listed as reference clauses).

[0081] Terms and Conditions Clause 1. A power receiver (PRx) for use in a wireless power system, the PRx comprising: a PRx slot circuit capable of receiving wireless power from a power transmitter and providing the wireless power to a load; a communication unit for communicating with the power transmitter; a controller configured to control the wireless power; a bias power supply circuit for obtaining sampled bias power from the PRx slot circuit, the communication unit, or both, and providing the sampled bias power to at least the controller; and an energy storage unit for providing energy to the bias power supply circuit when the sampled bias power is unavailable or below a threshold amount.

[0082] Clause 2. The power receiver as described in Clause 1, wherein the threshold amount is at least the amount of power required to operate the controller.

[0083] Clause 3. The power receiver as described in Clause 1 or 2 further includes: an impedance changing circuit capable of using energy from the energy storage unit to generate a wake-up signal.

[0084] Clause 4. A power receiver as described in Clause 3, wherein the wake-up signal wakes the power transmitter by causing the power transmitter to detect an impedance change.

[0085] Clause 5. A power receiver as described in Clause 3 or 4, wherein the impedance variation circuit is integrated with or coupled to at least one of the following: the secondary coil of the PRx slot circuit, or the antenna of the communication unit.

[0086] Clause 6. The power receiver as described in any one of Clauses 1 to 5 further comprises: a memory element, wherein the energy storage unit provides energy to maintain the volatile memory state of the memory element after an interruption of power transmission from the power transmitter.

[0087] Clause 7. The power receiver as described in any one of Clauses 1 to 6, wherein when the acquired bias power is unavailable, the energy storage unit supplies power to the load controller so that the load controller can operate the power receiver as planned.

[0088] Clause 8. The power receiver as described in any one of Clauses 1 to 7, wherein when the acquired bias power is not available to close and maintain the open switch, the energy storage unit provides energy to close and maintain the open switch of the PRx slot circuit based on a control signal from the controller.

[0089] Clause 9. The power receiver as described in any one of Clauses 1 to 8 further comprises: a network interface that communicatively couples the power receiver to a wireless network, wherein when the acquired bias power is not available to power the network interface, the energy storage unit provides energy to power the network interface.

[0090] Clause 10. A power receiver as described in any one of Clauses 1 to 9, wherein the energy storage unit comprises at least one of the following: a battery, a supercapacitor, a capacitor bank, or a combination thereof.

[0091] Clause 11. A method for a power receiver (PRx) comprising: attempting to obtain acquired bias power from a PRx slot circuit, a communication unit, or both, and providing the acquired bias power to a controller; and using energy from an energy storage unit when the acquired bias power is unavailable or below a level required to operate the controller.

[0092] Clause 12. The method of Clause 11 further includes: using energy from the energy storage unit to generate a wake-up signal via an impedance change circuit.

[0093] Clause 13. The method as described in Clause 12, wherein the wake-up signal wakes up the power transmitter by causing the power transmitter to detect a change in impedance.

[0094] Clause 14. The method as described in Clause 12 or 13 further comprises: generating the wake-up signal based on determining that the power receiver is activated in response to at least one of: a user interface command, a programmed schedule, or a message received via a network interface.

[0095] Clause 15. The method of any one of Clauses 12 to 14, wherein the impedance changing circuit is integrated with or coupled to at least one of the following: the secondary coil of the PRx slot circuit, or the antenna of the communication unit.

[0096] Clause 16. The method of any one of Clauses 11 to 15 further comprises: providing energy from the energy storage unit to the memory element to maintain the volatile memory state of the memory element after a power interruption until the power transmitter and the power receiver resume wireless power transmission.

[0097] Clause 17. The method of any one of Clauses 11 to 16 further comprises: supplying power from the energy storage unit to the controller when the acquired bias power is unavailable, so that the controller can maintain the load schedule.

[0098] Clause 18. The method of any one of Clauses 11 to 17 further comprises: when the acquired bias power is unavailable, using energy from the energy storage unit to close and maintain the open switch of the PRx slot circuit based on a control signal from the controller.

[0099] Clause 19. The method of any one of Clauses 11 to 18 further comprises: when the acquired bias power is not available to power the network interface of the power receiver, using energy from the energy storage unit to power the network interface.

[0100] Another innovative aspect of the subject matter described in this disclosure can be implemented as a computer-readable medium having instructions stored thereon that, when executed by a processor, cause the processor to perform any of the functions described above.

[0101] Another innovative aspect of the subject matter described in this disclosure can be implemented as a system having components that perform any of the functions described above.

[0102] Another innovative aspect of the subject matter described in this disclosure can be implemented as an apparatus having one or more processors configured to perform one or more operations of any of the methods described above.

[0103] As used herein, the terms indicating “at least one of” or “one or more of” in a list of items refer to any combination of these items, including a single member. For example, “at least one of a, b, or c” is intended to cover the following possibilities: only a, only b, only c, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a, b, and c.

[0104] The various exemplary components, logic units, logic blocks, modules, circuits, operations, and algorithm flows described in conjunction with the embodiments disclosed herein can be implemented as electronic hardware, firmware, software, or a combination of hardware, firmware, or software, including the structures disclosed in this specification and their structural equivalents. The interchangeability of hardware, firmware, and software has been generally described in terms of functionality and is illustrated in the various exemplary components, blocks, modules, circuits, and flows 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.

[0105] Hardware and data processing apparatuses for implementing the various exemplary components, logic units, logic blocks, modules, and circuits described in conjunction with the aspects disclosed herein may implement or execute a general-purpose single-chip or multi-chip processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic unit, discrete hardware unit, or combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors incorporating a DSP core, or any other such configuration. In some embodiments, specific processes, operations, and methods may be performed by circuitry dedicated to a given function.

[0106] As described above, some aspects of the subject matter described herein can be implemented as software. For example, the various functions of the components disclosed herein, or the 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-transitory processor-executable or computer-executable instructions encoded on one or more tangible, processor-readable or computer-readable storage media for execution by a data processing apparatus or for controlling the operation of such data processing apparatus, which includes components of the devices described herein. By way of example, but not limited to, such storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to store program code in the form of instructions or data structures. Combinations of the above should also be included within the scope of storage media.

[0107] Various modifications to the embodiments described in this disclosure may be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of this disclosure. Therefore, these claims are not intended to limit them to the embodiments shown herein, but are to be accorded the broadest scope of this disclosure, its principles, and novel features.

[0108] Additionally, the various features described in this specification in the context of multiple individual embodiments may also be implemented in combination in a single embodiment. Conversely, the various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments. Thus, although features may be described above as functioning in a particular combination and even initially required, in some cases one or more features from the required combination may be removed from the combination, and the required combination may be for sub-combinations or variations thereof.

[0109] Similarly, although operations are depicted in a specific order in the accompanying drawings, this should not be construed as requiring such operations to be performed in the indicated specific order or sequential order, or requiring all illustrated operations to be performed to achieve the desired result. Furthermore, the drawings may schematically depict one or more example processes in the form of flowcharts or block diagrams. However, other operations not depicted may be incorporated into the schematically illustrated example processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between the illustrated operations. In some cases, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be construed as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

Claims

1. A power receiver (PRx) for use in a wireless power system, the PRx comprising: A PRx slot circuit that can receive wireless power from a power transmitter and provide the wireless power to a load; A communication unit, wherein the communication unit is used to communicate with the power transmitter; A controller configured to control the wireless power; A bias power supply circuit is provided for obtaining the acquired bias power from the PRx slot circuit, the communication unit, or both, and providing the acquired bias power to at least the controller. and An energy storage unit is provided to supply energy to the bias power supply circuit when the acquired bias power is unavailable or below a threshold amount.

2. The power receiver of claim 1, wherein the threshold quantity is at least the amount of power required to operate the controller.

3. The power receiver as described in claim 1 or 2, further comprising: An impedance changing circuit is provided, which is capable of using energy from the energy storage unit to generate a wake-up signal.

4. The power receiver of claim 3, wherein the wake-up signal wakes up the power transmitter by causing the power transmitter to detect an impedance change.

5. The power receiver of claim 3 or 4, wherein the impedance variation circuit is integrated with or coupled to at least one of the following: The secondary coil of the PRx slot circuit, or The antenna of the communication unit.

6. The power receiver as claimed in any one of claims 1 to 5, further comprising: A memory element, wherein the energy storage unit provides energy to maintain the volatile memory state of the memory element after an interruption of power transmission from the power transmitter.

7. The power receiver of any one of claims 1 to 6, wherein when the acquired bias power is unavailable, the energy storage unit supplies power to the load controller so that the load controller can operate the power receiver according to a plan.

8. The power receiver of any one of claims 1 to 7, wherein when the acquired bias power is not available to close and maintain the open switch, the energy storage unit provides energy to close and maintain the open switch of the PRx slot circuit based on a control signal from the controller.

9. The power receiver as claimed in any one of claims 1 to 8, further comprising: A network interface that communicatively couples the power receiver to a wireless network. When the acquired bias power cannot be used to power the network interface, the energy storage unit provides energy to power the network interface.

10. The power receiver of any one of claims 1 to 9, wherein the energy storage unit comprises at least one of the following: Battery, Supercapacitors Capacitor bank, or Its combination.

11. A method for a power receiver (PRx), the method comprising: The system attempts to acquire the bias power from the PRx slot circuit, the communication unit, or both, and provides the acquired bias power to the controller. as well as When the acquired bias power is unavailable or below the level required to operate the controller, energy from the energy storage unit is used.

12. The method of claim 11, further comprising: Energy from the energy storage unit is used to generate a wake-up signal via an impedance change circuit.

13. The method of claim 12, wherein the wake-up signal wakes up the power transmitter by causing the power transmitter to detect an impedance change.

14. The method of claim 12 or 13, further comprising: The wake-up signal is generated based on determining that the power receiver is activated in response to at least one of the following: User interface commands A pre-programmed plan, or Messages received via network interface.

15. The method of any one of claims 12 to 14, wherein the impedance changing circuit is integrated with or coupled to at least one of the following: The secondary coil of the PRx slot circuit, or The antenna of the communication unit.

16. The method of any one of claims 11 to 15, further comprising: Energy from the energy storage unit is supplied to the memory element to maintain the volatile memory state of the memory element after a power interruption until the power transmitter and the power receiver resume wireless power transmission.

17. The method of any one of claims 11 to 16, further comprising: When the acquired bias power is unavailable, power from the energy storage unit is supplied to the controller so that the controller can maintain the load schedule.

18. The method of any one of claims 11 to 17, further comprising: When the acquired bias power is unavailable, energy from the energy storage unit is used to close and maintain the open switch of the PRx slot circuit based on the control signal from the controller.

19. The method of any one of claims 11 to 18, further comprising: When the acquired bias power cannot be used to power the network interface of the power receiver, energy from the energy storage unit is used to power the network interface.

Images