Power control for overvoltage protection in wireless power system

Abstract

This disclosure provides systems, methods, and apparatus for power control in a wireless power system. The disclosed techniques enable a power transmitter to mitigate an overvoltage state of a power receiver. In some aspects, a power transmitter adjusts an operating point of a wireless power signal based on a control error (CE) data packet from a power receiver. The power transmitter determines an average baseline power after processing the CE data packets. The power transmitter may also adjust the operation point prior to receiving the next CE data packet. In some aspects, the power transmitter adjusts the operating point when the average measured power is different from the average baseline power. A power transmitter may adjust an operating point between instances of periodic control error (CE) data packets to mitigate overvoltage conditions at a power receiver due to sudden load changes.

Description

Technical Field

[0001] This disclosure relates in its entirety to wireless power, and specifically to overvoltage protection in wireless power systems. Background Technology

[0002] A wireless power system comprises a power transmitter (PTx, sometimes also called a wireless power transmitting device) and a power receiver (PRx, sometimes also called a wireless power receiving device). The power transmitter includes a primary coil. When the secondary coil of the power receiver is positioned near the primary coil, the primary coil generates an electromagnetic field during the power transfer phase to induce a voltage in the secondary coil. When the secondary coil is coupled to a rectifier, the induced voltage can generate power. Therefore, the power transmitter can wirelessly transfer power to the power receiver. Power can be transferred using inductive or resonant coupling between the primary and secondary coils. The power receiver can provide the generated power to operate loads such as motors, heating elements, electronic devices, or power storage devices.

[0003] During the power transmission phase, the power transmitter controls the operating point of the wireless power signal. In conventional wireless power systems, the power transmitter controls the operating point based on feedback information (such as control error values) from the power receiver. The operating point can include the voltage, frequency, phase, or other parameters of the wireless power signal. The power receiver periodically transmits feedback information in control error data packets (CE data packets). Each CE data packet can include a control error value that causes the power transmitter to modify the power, current, voltage, or another parameter at the operating point. CE data packets are transmitted during communication periods based on the wireless power system's communication protocol. There is an inherent delay between each CE data packet based on the timing of the communication periods. Because the wireless power system is used to transmit higher power levels, the delay between CE data packets can lead to overvoltage conditions during the delay period. The timing of the communication periods may be too slow, or the control error value may be provided too infrequently, preventing the power receiver from responding to load changes or power demands. Furthermore, because higher power wireless power systems may experience significant changes in load power demands, there is a possibility of overvoltage conditions occurring during the time between CE data packets. Summary of the Invention

[0004] The systems, methods, and apparatuses disclosed herein each have several innovative aspects, and no single aspect alone can bear full responsibility for the desired characteristics disclosed herein.

[0005] In one aspect, a method performed by a power transmitter includes: transmitting a wireless power signal to a power receiver; receiving a first control error value from the power receiver; adjusting an operating point of the wireless power signal based on the first control error value; and averaging a baseline power (P) after adjusting the operating point. baseline The P of the wireless power signal was determined during the measurement period. baseline ; in the P baseline At least one average calculated power (P) after the measurement period and before receiving the second control error value from the power receiver calculated The P value of the wireless power signal is calculated during the measurement period. calculated ; and at least in part based on the P baseline and the P calculated The difference between them is used to control the operating point.

[0006] In one aspect, a method performed by a power transmitter includes: transmitting a wireless power signal to a power receiver; adjusting the operating point of the wireless power signal based on periodic control error (CE) data packets received from the power receiver, the periodic CE data packets including at least a first CE data packet and a second CE data packet; and a control error interval (t) between the first CE data packet and the second CE data packet. interval During this period, when the load on the power receiver changes, the overvoltage state of the power receiver is mitigated, wherein mitigating the overvoltage state includes adjusting the operating point based on the difference between: the baseline power (P) of the wireless power signal based on a first measurement at the power transmitter after the first CE data packet. baseline ), and based on the P baseline The calculated power (P) of the wireless power signal at the second measurement value at the power transmitter is then used to calculate the power of the signal. calculated ).

[0007] In one aspect, a method performed by a power receiver includes: transmitting power configuration information to a power transmitter, the power configuration information enabling overvoltage protection for the load of the power receiver; receiving a wireless power signal from the power transmitter; and, during a power transmission phase, periodically transmitting a control error value to the power transmitter.

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

[0009] The same reference numerals and designations in various figures indicate the same elements. For ease of identification of discussions concerning any particular element or action, one or more of the highest significant digits in the reference numerals refer to the reference numeral that first introduced that element. Note that the relative dimensions of the figures may not be drawn to scale.

[0010] Figure 1 This is a block diagram of an example wireless power system, including an example power transmitter and an example power receiver.

[0011] Figure 2A An example DC voltage of a power transmitter is shown, wherein the DC voltage varies proportionally to the power required by the power receiver.

[0012] Figure 2B An example DC voltage of a power transmitter is shown, wherein the DC voltage varies in steps according to the power required by the power receiver.

[0013] Figure 3 A message flow diagram of an example wireless power transmission process is shown.

[0014] Figure 4 An example of a control loop executed between a power transmitter and a power receiver is shown.

[0015] Figure 5 A controller for controlling the operating point of a power transmitter is shown conceptually according to some aspects of this disclosure.

[0016] Figure 6 This is a timing diagram showing power control according to some aspects of this disclosure.

[0017] Figure 7A Electrical parameters of a wireless power system using a conventional controller that does not employ the technology disclosed herein are shown.

[0018] Figure 7B Electrical parameters of a wireless power system using a power controller with overvoltage protection, according to some aspects of this disclosure, are shown.

[0019] Figure 8 This is a flowchart illustrating an example operation of the power control process performed by the power transmitter.

[0020] Figure 9 This is a flowchart illustrating an example operation of another process used for power control.

[0021] Figure 10 This is a flowchart illustrating an example operation of a process for overvoltage protection.

[0022] Figure 11 This is a flowchart illustrating an example operation of the power receiver process.

[0023] Figure 12 A conceptual flowchart of an example message for transmitting power configuration information is shown, according to some aspects of this disclosure.

[0024] Figure 13 This is a flowchart of an example device for use in a wireless power system. Detailed Implementation

[0025] The following description is for the purpose of describing certain embodiments of the innovative aspects of this disclosure. However, those skilled in the art will readily recognize that the teachings herein can be applied in many different ways. The embodiments described herein can be implemented in any component, apparatus, system, or method for transmitting or receiving wireless power.

[0026] A wireless power system may include a power transmitter (sometimes referred to as a power transmitter, or PTx) integrated with or otherwise disposed on the interface surface of a power transmitter. The wireless power system may also include a power receiver (sometimes referred to as a power receiver, or PRx). The power transmitter may include a primary coil configured to wirelessly transmit power to a secondary coil in the power receiver via a magnetic field. In some embodiments, the power transmitter may include a countertop-mounted primary coil or a primary coil embedded in or fabricated on a surface where a cordless appliance may be placed. The cordless appliance may include a power receiver for wirelessly receiving power. The secondary coil of the power receiver may obtain wireless energy from a magnetic field and supply it to a power receiving circuit. The power receiving circuit may convert the energy and use it to charge or power a load. The power receiver may be included in or integrated with a cordless appliance with a variable load, such as a stirrer, heating element, fan, etc.

[0027] During the power transfer phase, the power receiver can transmit feedback information to the power transmitter via a communication channel. The power receiver can transmit feedback information during the communication period. Power feedback information can indicate presence or status, etc. For example, feedback information may include a power request, no communication (indicating presence but no feedback), or power receiver feedback. For example, the power transmitter and power receiver can communicate via Near Field Communication (NFC), Bluetooth™, or other communication technologies. The transmission of wireless power can be controlled by several types of feedback information, such as control error data packets (CE data packets) or power control packets transmitted from the power receiver to the power transmitter. Each CE data packet includes a control error value (such as voltage error (V)). errorThe control error value can be referred to as feedback information or control information. Although the examples in this disclosure are based on the delay between CE data packets, the same technique applies to the delay between other types of power control information, such as power control packets or received power packets.

[0028] The power transmitter periodically adjusts the operating point (such as voltage or current) of the wireless power signal based on feedback information from the power receiver. For example, the power transmitter may adjust the operating point based on a control error value in the CE data packets. The power controller may implement a control loop in which the power receiver periodically transmits a control error value that allows the power transmitter to adjust the operating point. However, the control error value is transmitted during a communication period according to the communication protocol. In some implementations, each communication period occurs during a communication silence period (t) following the end of a previous power control packet. silent After that. In some implementations, CE data grouping is based on the control error interval (t). interval The power receiver is expected to transmit CE data packets throughout the power transmission phase. interval This represents the time interval between the start of consecutive CE data packets. t interval It does not need to be a constant and can vary within the limits defined by the communication protocol. For example, t interval It can vary within a range between 0 milliseconds (ms) and 700 ms. In some implementations, the target t interval It takes approximately 250 ms.

[0029] As wireless power systems evolve to increase power levels, periodic CE data packets may not be sufficient to quickly adjust the operating point due to latency or communication inefficiencies. For example, power receivers can have significant variations in load power requirements (such as from 300 watts (W) to 0W or 5W). Load variations can cause very high transient overvoltages on the power receiver circuitry or may damage the power receiver. To mitigate overvoltages, some power receivers may include load capacitance. Load capacitance can slow the rise of overvoltages; however, added load capacitance may consume additional space or increase the overhead of the power receiver. Because power receiver manufacturers are free to choose load capacitance based on load power, cost, and space constraints, the time it takes for the voltage in the power receiver to rise from the nominal voltage to an allowable overvoltage state depends on the load thrown level and the size of the load capacitance.

[0030] This disclosure provides systems, methods, and apparatus for power control in wireless power systems. The power control described herein enables a power transmitter to mitigate overvoltage conditions in a power receiver. In some embodiments, the power transmitter monitors power variations at the power transmitter circuitry and adjusts its operating point when the average measured power differs from a baseline power established by a conventional control loop. The power transmitter can adjust the operating point of the wireless power signal more frequently than when using only periodic CE data packets. For example, the power transmitter can adjust the operating point to mitigate overvoltage conditions that would otherwise occur between CE data packets.

[0031] The power transmitter determines the baseline power (P) of the wireless power signal. baseline For example, P can be calculated after adjusting the operating point using the control error value. baseline P baseline Based on P baseline The first measurement (such as voltage and current measurements) at the power transmitter during the measurement period. This first measurement can be obtained from the DC input of the power driver or from the resonant tank circuit of the power transmitter. The power transmitter can average the first measurement over a power averaging time (such as 0.5 ms, 1 ms, or 2 ms as examples). Due to P baseline It is determined during the first instance of the power averaging time after the operating point change, so the first instance of the power averaging time can be referred to as P. baseline Measurement period (or baseline measurement period). The power transmitter can determine the power averaging time based on its own operating parameters, parameters received from the power receiver, or a combination thereof. In determining P... baseline Subsequently, the power transmitter periodically calculates the average computed power (P) based on the average of subsequent measurements (referred to as the second measurement) at the power transmitter. calculated Similar to the first measurement, the second measurement can include voltage and current measurements at the DC input or at the resonant circuit of the power transmitter. This can be referred to as P. calculated Determine P during the power averaging time of the measurement period calculated Each instance of P. In some implementations, P baseline Measurement time period and each P calculated The duration of the measurement period can be the same duration as the power averaging time. In some implementations, P calculated This can be referred to as measuring power (P) measured ), average power (P) average ) or actual power (P) actual The power transmitter can be based on P. baseline and P calculatedThe power error value (P) is calculated from the difference between them. error In some implementations, the power controller can use a similar operating point calculation (such as a proportional-integral-derivative (PID) algorithm) to be used with the control error value. For example, the power transmitter can use the power error value to adjust the reference current used for the PID algorithm.

[0032] In some implementations, the power receiver may send additional information (which may be referred to as power configuration information) to the power transmitter during the configuration or negotiation phase to help the power transmitter determine the operating point, power control settings, or both. For example, the power configuration information may include the value of the load capacitance used in the power receiver, the rated load voltage, the permissible overvoltage level, the time required for the load to reach the permissible overvoltage state from the rated nominal voltage state when the load is switched from full load to no load, and the information used by the power transmitter to calculate P. baseline or P calculated The power average time used, or any combination of the above information. The power transmitter can use the power configuration information to determine the required power for P. calculated At least one of the following is performed: the speed, duration, and interval of averaging to detect power changes before an overvoltage condition. Additionally or alternatively, the power receiver may be used in a test environment with a standard power transmitter to transmit a recommended power averaging time based on empirical test results.

[0033] Specific embodiments of the subject matter described in this disclosure may be implemented to achieve one or more of the following potential advantages. The power transmitter can be more powerful than the t associated with CE data packets. interval The operating point of the wireless power signal can be controlled more frequently. The power transmitter can adjust its operating point based on measurements taken at the power transmitter between CE data packets, sometimes without needing to receive measurement information from the power receiver. By using the disclosed power control, the power transmitter can respond to feedback information from the power receiver (such as CE data packets) while mitigating overvoltage conditions that would otherwise occur between CE data packets. The described power control enables the wireless power system to support battery charging applications for the power receiver or applications where the power receiver powers the load wirelessly without a battery.

[0034] Figure 1 This is a block diagram of an example wireless power system 100, including an example power transmitter 102 and an example power receiver 118. Figure 1 In the diagram, dashed lines represent communication to distinguish them from solid lines representing electrical circuits.

[0035] Power transmitter 102 includes a primary coil 104 and a transmit (TX) controller 108. The primary coil 104 may be associated with power transmitter circuitry 106 (sometimes also referred to as a power signal generator or driver circuit). The primary coil 104 may be a coil that transmits wireless power (also referred to as wireless energy). The primary coil 104 may transmit wireless energy using an inductive field or a magnetic resonant field. Power transmitter circuitry 106 may include components (not shown) for preparing wireless power. For example, power transmitter circuitry 106 may include one or more switches, drivers, series capacitors, rectifiers, inverters, or other components. In some embodiments, power transmitter circuitry 106, PTX controller 108, and other components (not shown) may be collectively referred to as power transmitter unit 110. Some or all of power transmitter unit 110 may be embodied as an integrated circuit (IC) implementing the features of this disclosure for controlling wireless power and transmitting wireless power to one or more wireless power receiving devices. PTX controller 108 may be implemented as a microcontroller, a dedicated processor, an integrated circuit, an application-specific integrated circuit (ASIC), or any other suitable electronic device.

[0036] Power source 112 provides power to power transmitter unit 110. In some embodiments, power source 112 can convert alternating current (AC) power to direct current (DC) power. For example, power source 112 may include a converter that receives AC power from an external power source and converts the AC power into DC power used by power transmitter circuit 106. Alternatively or additionally, components of power transmitter circuit 106, such as an inverter, can convert DC power to AC power. Power source 112 may be integrated into power transmitter 102 or may be external to power transmitter 102.

[0037] In some implementations, the power transmitter 102 causes the power source 112 to regulate its DC output voltage. For example, the power source 112 may be based on the power supplied to the power receiver 118 (such as P determined by the power transmitter). baseline The DC output voltage is regulated to different levels by the rated power of the power receiver 118 or the power source 118. In some embodiments, the PTX controller 108 can set the DC voltage of the power source 112 based on information received from the power receiver 118, such as the required power. The DC output voltage can be as follows: Figure 2A The voltage varies proportionally to the power supplied to power receiver 118. In other embodiments, the DC output voltage can be varied in steps, such as... Figure 2BThe same value is maintained across the power range delivered to power receiver 118. Power transmitter 102 can adjust the DC output voltage level of power source 112 to maximize the overall efficiency of wireless power system 100. Power transmitter 102 can receive power configuration information from power receiver 118 and use this information to set parameters such as the DC output voltage of power source 112. Power transmitter 102 can receive power configuration information during various operational phases, such as configuration or power transmission phases. In some embodiments, power transmitter 102 includes a DC-DC converter (not shown) between power source 112 and power transmitter circuitry 106 to control the variable DC output voltage.

[0038] The PTX controller 108 is connected to a first communication interface 114. The first communication interface 114 is connected to a first communication coil 116. In some embodiments, the first communication interface 114 and the first communication coil 116 may be collectively referred to as a first communication unit 122. In some embodiments, the first communication unit 122 may support Near Field Communication (NFC). NFC is a technology for data transmission on a carrier frequency of 13.56 MHz. In some embodiments, the first communication unit 122 may support Bluetooth (BT) communication. The first communication unit 122 may also support any suitable communication protocol. The first communication unit 122 may include modulation and demodulation circuitry for wireless communication via the first communication coil 116. Alternatively or additionally, the TX controller 108 may use frequency modulation to communicate via an in-band communication link (not shown) including a primary coil 104.

[0039] Power receiver 118 may include a secondary coil 120, a rectifier 124, a receiver (RX) controller 126, a second communication interface 130, a load controller 134, a load 128, and memory (not shown). In some embodiments, the load 128 may include a drive (not shown) for controlling at least one parameter such as the charging current, speed, or torque of the load. In some embodiments, the rectifier 124 may be omitted. In some embodiments, a series switch (not shown) may be included, connected in series with the secondary coil 120 or in series between the rectifier 124 and the load 128. A load capacitor (though not shown) may be used after the rectifier 124 to reduce the rate of rise of the load voltage that will occur when the load 128 suddenly reduces power consumption. Although shown as different components, some components may be packaged or implemented in the same hardware. For example, in some embodiments, the RX controller 126 and the load controller 134 may be implemented as a single controller. The RX controller 126, the load controller 134, or any combination thereof may be implemented as a microcontroller, a dedicated processor, an integrated circuit, an application-specific integrated circuit (ASIC), or any other suitable electronic device.

[0040] The PTX controller 108 can detect the presence or proximity of the power receiver 118. This detection can occur during a periodic network probing (ping) process of the first communication interface 114. During the ping process, when the power receiver 118 approaches the power transmitter 102, the first communication interface 114 can also supply power to the second communication interface 130. The second communication interface 130 can "wake up" and power on the RX controller 126, and can send a reply signal back to the first communication interface 114. A handshake process can occur before power transmission, during which the PTX controller 108 can receive configuration data related to the receiver's rated power, as well as other information. The PTX controller 108 can control the characteristics of the wireless power it provides to the power receiver 118 based on the configuration data.

[0041] The RX controller 126 is operatively coupled to the rectifier 124 and a second communication interface 130. The second communication interface 130 may include modulation and demodulation circuitry for wireless communication via a second communication coil 132. Therefore, the RX controller 126 can use NFC communication to wirelessly transmit feedback information to the PTX controller 108 via the second communication interface 130 to the first communication interface 114. Alternatively or additionally, the RX controller 126 can use load modulation to communicate via an in-band communication link (not shown) including a secondary coil 120.

[0042] Load controller 134 is operatively coupled to load 128 and a second communication interface 130. Load controller 134 can detect changes in load conditions, such as changes in charging current in a battery charging application. Load controller 134 can also determine a load voltage reference. Load controller 134 can also load the voltage reference, load current, and any other suitable information to RX controller 126 or the second communication interface 130 for communication with power transmitter 102. RX controller 126 can additionally determine and provide feedback information indicating a measured load voltage that can be used for load 128. In some feedback messages, the feedback information may include a reference voltage indicating the desired voltage for load 128. In some feedback messages, the feedback information may indicate an error in the output voltage of load 128. In some feedback messages, the feedback information may include the power required by the load. Although RX controller 126 and load controller 134 are shown separately, they can be included in the same components of power receiver 118.

[0043] Power transmitter 102 is used as further referenced. Figure 4 and Figure 5The described control loop and control algorithm control the operating point of the power transmitter circuit 106. When the PTX controller 108 receives a control error value from the power receiver 118, the PTX controller 108 uses the control error value to calculate the reference current (I0). reference The PTX controller 108 also uses a sensor (not shown) to obtain the measured current (I). measured ), where I measured This is the current at the power transmitter circuit 106. The PTX controller 108 uses I... reference I measured The control algorithm is used to calculate the operating point for the power transmitter circuit 106. The operating point can be voltage (also known as operating voltage), current (also known as operating current), duty cycle, phase shift, or other parameters that control how the power transmitter circuit 106 drives the wireless power signal to the primary coil 104.

[0044] Additionally, according to aspects of this disclosure, the PTX controller 108 can adjust its operating point based on a change in transmission power, wherein the change occurs after the first CE data packet and before the second CE data packet. The PTX controller 108 can adjust its operating point based on the P... baseline The first measurement during the measurement period determines P. baseline Then, the PTX controller 108 can be based on P... baseline P after the measurement period calculated P is calculated from the second measurement value during the measurement period. calculated If P calculated Relative to P baseline If the deviation from the threshold amount is significant, the change may be a result of a load change at the power receiver. The PTX controller 108 can adjust the operating point in response to this change without waiting for the next CE data packet or power control packet to report the change.

[0045] Figure 2A An example direct current (DC) voltage of a power transmitter is shown, wherein the DC voltage varies proportionally to the power required by the power receiver. First Figure 200a shows the DC output voltage of the power source in the power transmitter. The DC output voltage can be increased as a proportional variable to achieve an increase in the power delivered to the power receiver. In some embodiments, the power receiver transmits a power demand to the power transmitter. In some embodiments, the power transmitter can measure the transmitted power. The power transmitter sets the DC output voltage in the power source based on calculations proportional to the power demand or transmitted power.

[0046] Figure 2BAn example DC voltage of a power transmitter is shown, wherein the DC voltage varies in steps according to the power required by the power receiver. In one embodiment, the DC voltage can vary in steps according to the power transmitted by the power transmitter. A second figure 200b shows the DC output voltage of the power source in the power transmitter based on the power demand of the power receiver. The DC output voltage can have steps at different DC output voltage levels to achieve different ranges of power delivered to the power receiver. In some embodiments, the power transmitter receives communication from the power receiver requesting a power amount or power demand. The power transmitter determines which range includes the requested power amount or power demand. The power transmitter sets the DC output voltage in the power source to a DC output voltage level corresponding to the determined range.

[0047] Figure 3 A message flow diagram of an example wireless power transmission process is shown. (Reference) Figure 3 The power transmitter 102 detects that the power receiver 118 is in the charging region of standby mode (box 302). The power transmitter 102 can have various methods for detecting the power receiver 118, and is not limited to the specific methods disclosed herein. As an example, the power transmitter 102 can detect that the power receiver 118 is in the charging region by periodically transmitting an analog ping at a specific frequency and detecting current, resonant offset, or capacitance change in response. As another example, the power transmitter 102 can periodically transmit a detection signal, and the power receiver 118 can transmit a response signal (e.g., a CE data packet or signal strength packet). The power transmitter 102 can detect that the power receiver 118 is in the charging region based on receiving the response signal within a predetermined time period after the detection signal. As yet another example, the power receiver 118 can transmit a search signal or an advertisement signal to the power transmitter 102. Search signals or advertisement signals conventionally use short-range radio frequency communication (e.g., Bluetooth). TM The power transmitter 102 can detect the power receiver 118 based on the received search signal or announcement signal.

[0048] In some implementations, when preparing for wireless power transmission, the power transmitter 102 may optionally transmit an information request signal 304 to the power receiver 118. The information request signal 304 may be a signal requesting the ID and power information of the power receiver 118. As an example, the information request signal 304 may be transmitted in the form of a data packet message. As another example, the information request signal 304 may be transmitted between the power transmitter 102 and the power receiver 118 in the form of a digital ping according to a predefined standard. In response to the information request signal 304, the power receiver 118 may optionally transmit ID and configuration information 306 to the power transmitter 102. For example, the configuration information may include the nominal power of the power receiver 118 or the maximum amount of power required. In some implementations, the ID and configuration information 306 may also include power configuration information to assist the power transmitter 102 in setting up the P... baseline Measurement period and P calculated The duration of the measurement period, the overvoltage protection threshold, or other parameters of the power controller. In some implementations, out-of-band communication (separate from the wireless power signal) such as NFC or Bluetooth can be used to transmit the information request signal 304 and ID and configuration information 306.

[0049] Based on the ID and configuration information 306, the power transmitter 102 configures parameters for power transmission (referred to as the operating point) and performs wireless power transmission 308 to the power receiver 118. For example, the power transmitter 102 can create a power transmission contract based on the ID and configuration information and control the wireless power transmission 308 according to the power transmission contract. The process from start to finish of the wireless power transmission 308 performed by the power transmitter 102 to the power receiver 118 can be referred to as the (wireless) power transmission phase 314. The power receiver 118 can then provide the received wireless power to an external load (e.g., a battery).

[0050] During the power transmission phase 314, the power receiver 118 periodically or non-periodically transmits CE data packets (such as CE data packets 310a, 310b, 310c) to the power transmitter 102. After each CE data packet, the power transmitter 102 can perform a reference... Figure 5 The control process is described. CE data packets are transmitted during communication periods. In some implementations, communication periods occur during periodic intervals allocated for communication. For example, each communication period may be a time interval (such as the control error interval t) following the start of a previous CE data packet. interval Begin within (). t interval It can vary within the range of 0 ms to 700 ms (where the specified target is 250 ms). The power receiver can be configured for tinterval Transmit CE data packets within the specified limits. Therefore, t interval Periodicity can be created for CE data packets 310a, 310b, and 310c. In some implementations, the power receiver attempts to target t 250ms after the start of a previous CE data packet. interval The next CE data packet is transmitted in time. Depending on when the power receiver transmits each CE data packet, there may be a variable delay (T) of up to 700 milliseconds (ms) between CE data packets 310a, 310b, and 310c.

[0051] In some instances, the load state can change during a delay (T). For example, Figure 3 The load change 312 that occurred shortly after the first CE data packet 310a is shown. Based on t interval The power receiver 118 may not transmit the next CE data packet (second CE data packet 310b) for up to 700 ms. Without the technology disclosed herein, a load change 312 could cause a high transient overvoltage in the power receiver 118. For example, the load could change from a high power requirement (such as 200W) to a low power requirement (such as 0W or 5W). Because conventional power controllers are configured to maintain an operating point between CE data packets, the power transmitter 102 might use the same control inputs for transmitting a 200W power requirement to transmit wireless power for a period of time until the next CE data packet 310b can indicate a new power setting based on the load change 312.

[0052] Figure 4 An example of a control loop 400 executed between power transmitter 102 and power receiver 118 is shown. (Reference) Figure 4 The power receiver 118 selects a desired control point (block 402). For example, the control point can be based on the current, voltage, or power demand of the load on the power receiver 118. The power receiver 118 bases its selection on the power pickup unit 408 (such as a reference unit). Figure 1 The wireless power signal 422 received by the described secondary coil and rectifier is used to determine the actual control point 406.

[0053] At block 404, power receiver 118 uses the desired control point and the actual control point to calculate a control error value. For example, power receiver 118 can calculate the control error value using the (relative) difference between the desired voltage (or current) and the actual voltage (or current). Power receiver 118 generates control signaling 410 based on the control error value and transmits it to power transmitter 102. In conventional communication technologies, control signaling 410 can be encoded in CE data packets.

[0054] Power transmitter 102 receives control signaling 410. If needed, power transmitter 102 can use control signaling 410 to set a new operating point (box 416). In this document, for example, the operating point can be at least one of the amplitude, frequency, and duty cycle of the AC voltage applied to the primary coil. To determine the new operating point (box 416), power transmitter 102 can determine a new primary cell current (box 412). The new primary cell current can be based on the actual primary cell current (box 420) and control signaling 410. Power transmitter 102 can determine control over the new primary cell current (box 414) and determine the new operating point (box 416) to satisfy the new primary cell current.

[0055] Power transmitter 102, based on a new operating point (determined in block 416), via power conversion unit 418 (such as reference 418) Figure 1 The described power transmitter unit 110 transmits a wireless power signal 422 to a power receiver 118. Without the technology disclosed herein, the power transmitter 102 can maintain its operating point until it receives new control signaling from the power receiver 118.

[0056] Figure 4 A control loop 400 including aspects of a power transmitter 102 and a power receiver 118 is described. Embodiments of blocks 412, 414, 416, and 420 can be further described as a controller for the power transmitter 102 (such as reference 118). Figure 1 The PID algorithm or control algorithm described in the PTX controller 108 or processor. Figure 5 A description of the controller's conventional PID algorithm is provided, as well as modifications to the PID algorithm to support changes in operating points between CE data packets.

[0057] Figure 5 A controller for controlling the operating point of a power transmitter is shown conceptually according to some aspects of this disclosure. The controller 500 can be implemented as described in reference... Figure 4 The process described in blocks 412, 414, 416, and 420 (combined) is described. Controller 500 can be implemented as a TX controller for a power transmitter (such as reference...). Figure 1 The described PTX controller 500 (or processor) is used. For the sake of brevity, the operation of the controller 500 is described as the operation of a power transmitter.

[0058] Power transmitter receive control error value. Figure 5 In the middle, the control error value is V error 504. The power transmitter also obtained I measured 506, the I measured506 is the current measured at the power transmitter unit of the power transmitter. At box 502, the power transmitter connects to V... error 504 multiplied by the variable factor (k) measured and I measured The sum is used to calculate the reference current (I). reference 508. Then, during the adjustment based on CE data grouping, I is placed at box 510. reference 508 and I measured 506 compares to calculate I error 512. I error 512 represents I reference 508 and I measured The difference between 506 and 506. Then, the PID controller 514 calculates the operating point signal 516 to provide to the driver (such as the power transmitter unit 110) to control the operating point.

[0059] Figure 5 The bold lines in the text indicate example modifications to controller 500 that enable controller 500 to adjust the operating point between CE data packets based on power measurements. Example modifications include power increment calculation 518 and adder 532 added to the conventional controller 500. In power increment calculation 518, the power transmitter is based on P... calulated 520 and P baseline The difference between 522 and 524 is used to calculate P. error 526. P baseline 522 is the average power calculated at the power transmitter after adjusting the operating point based on previous control error values. baseline 522 can be the power averaging time (referred to as P) that occurs after the operating point is changed. baseline The average power during the measurement period. P calulated 520 is in determining P baseline The average power is then calculated periodically at the power transmitter. Because P baseline 522 and P calulated 520 is averaged separately, therefore used for P calulated 520 power average time (P) calulated The measurement period can be used with P baseline 522 power average time (P) baseline The measurement time periods may be the same or different. In some implementations, the first instance of the power averaging time is referred to as P. baseline The measurement period, and subsequent instances of power averaging time, are referred to as P. calulated Measurement period.

[0060] For P baseline and P calulatedSecondly, the power transmitter can obtain voltage and current measurements at the power transmitter itself without requiring communication from the power receiver. For example, voltage and current measurements can be obtained from the DC input of the power transmitter unit (such as the DC input of an inverter). In another example, voltage and current measurements can be obtained from a resonant circuit connected to the output of the power transmitter unit. The resonant circuit includes the primary coil of the power transmitter and a resonant capacitor. In some implementations, P can be adjusted by a variable factor (k2) at block 528. error 526. P error 526 (or adjusted P) error 530) can be added (at box 532) to I reference 508 to generate the modified reference current I reference 434. Then, at box 510, the power transmitter uses a modified I... reference 534 and I measured 506 to calculate I error 512. The remaining calculations proceed normally, including those using the PID controller 514 with I... error 512 (now based on the modified I) reference 534) Determine the operating point signal 516. In some embodiments, the power increment calculation 518 may be directly added to the output of the PID controller 514 to affect the operating point signal 516. The power transmitter can use the power increment calculation 518 to sense a sudden change in power between two consecutive CE data packets. The power increment calculation 518 causes a change in 516. Therefore, in response to the sudden change in power, the power transmitter reduces the voltage and / or current applied to the primary tank circuit to avoid overvoltage in the power receiver. In some embodiments, the power increment calculation 518 may be any calculation in which the power transmitter senses a sudden change in power delivered to the power receiver that is independent of the change in operating point, based on the feedback-based control mechanism.

[0061] Recalculate the power increment 518, P calulated 520 and P baseline 522 can be further described in relation to the timing of the feedback-based control mechanism. For example, P can be calculated immediately or very quickly after the operating point is adjusted based on the most recent control error value and blocks 502, 510, and 514. baseline 522. P baseline The 522 can be changed after each iteration of the control loop and after each adjustment of the operating point using the control error value. The power transmitter can store P in memory. baselineThis is for use in power increment calculations 518 performed between two consecutive CE data packets. Conversely, P calulated 520 is based on the already calculated P baseline Voltage and current measurements obtained after 522. P calulated 520 can vary based on load changes affecting the power transmitter resonant circuit or driver circuit. When large load changes occur, P calulated The 520 may undergo significant changes. Therefore, the power transmitter can respond quickly (e.g., within 1 to 2 ms) to large load changes that occur after one CE data packet and before the next CE data packet (which can be up to 250 ms later).

[0062] Figure 6 This illustrates a timing diagram 600 for power control according to some aspects of this disclosure. See reference... Figure 3 As described, the power receiver 118 periodically transmits CE data packets 310a, 310b, and 310c. Each CE data packet includes a control error value. The power receiver 118 transmits CE data packets 310a, 310b, and 310c during communication periods. Figure 6 The control error interval 602 (t) between the start of the first CE data packet 310a and the start of the second CE data packet 310b is shown. interval ). Figure 6 The communication period 604 is shown when the power receiver 118 transmits CE data packet 310b.

[0063] After each CE data packet 310a, 310b, and 310c, the power transmitter 102 adjusts the operating point based on the control error value in the CE data packet. Furthermore, the power transmitter 102 determines P... baseline 522. Subsequently, the power transmitter 102 obtains voltage and current measurements at the power transmitter to calculate P. calulated 520. P can be frequently measured and calculated between each communication period. calulated 520. For example, P can be frequently measured and calculated during the control error interval 602 between the first CE data group 310a and the second CE data group 310b. calulated Power transmitter 102 is based on P calulated 520 and P baseline Calculate P using the difference between 522 and 522. error P error For reference only Figure 5 The power increment calculation described in 518 is used. The power transmitter 102 modifies the I used for calculating the PID algorithm. error I referenceEven before receiving the next CE data packet (such as the second CE data packet 310b), the power transmitter 102 can adjust its operating point as needed during the control error interval 602.

[0064] Figure 7A Electrical parameters 700b of a wireless power system using a conventional controller that does not employ the technology disclosed herein are shown. Figure 7A The chart in the figure is a time curve of PTx current, PTx voltage, and PTx resonant power at the power transmitter relative to load current, load voltage, PRx resonant current, PRx resonant voltage, and load switching at the power receiver.

[0065] The first control error value can be transmitted in the first CE data packet during the first communication period. For simplicity, the first CE data packet is shown as the first communication event 702. Without the technology disclosed herein, the power transmitter would set its operating point based on the first control error value and then maintain the operating point until the next CE data packet (shown as the second communication event 704). However, at time 706, the power receiver may experience a load change (also known as load switching, load throw, or load switching). For example, the load power demand may change from 200 W to 5 W. The load current 708 may decrease due to the load change. However, since the power transmitter will maintain its operating point until the second communication event 704, the load voltage 710 and the PRx resonant voltage 714 may increase. An overvoltage condition may occur, which could damage the load or the power receiver or create an unsafe fire or electrical hazard. The overvoltage condition may persist until the second communication event 704 when the power transmitter receives the new control error value and adjusts its operating point for the PTx current, PTx voltage, and PRx resonant circuit power (shown at circle 716).

[0066] Figure 7B Electrical parameters 700b of a wireless power system using a power controller with overvoltage protection, according to some aspects of this disclosure, are shown. After a first communication event 702, the power transmitter can adjust the operating point of the wireless power signal. After adjusting the operating point based on the control error value received at the first communication event 702, the power transmitter at P... baseline P was determined during the measurement period of 720. baseline In P baseline After the measurement period of 720, the power transmitter can be at P baseline P was measured and calculated during measurement period 722. calulated Although only one P is shown. calulated Measurement period 722, but at P baselineSeveral Ps may exist after measurement period 720 and before the second communication event 704. calulated Measurement period.

[0067] For reference Figure 7B The load change, as described, occurred at time 706. However, Figure 7B Unlike Figure 7A Because the power transmitter is more P baseline and P calulated And determine P error (P) baseline and P calulated The difference between them is higher than the threshold. When P error When the voltage exceeds a threshold, the power transmitter adjusts its operating point (shown at circle 712) to prevent overvoltage conditions in the power receiver. In experimental tests using the described overvoltage protection features, transient load spikes (shown at circle 718) persist for only a short period and remain below the threshold (such as 58 volts (V)).

[0068] Figure 8 This is a flowchart illustrating an example operation of a power control process 800 performed by a power transmitter. The operation of process 800 can be implemented by a controller or processor of the power transmitter (such as any of the power transmitters 102 described herein). In some embodiments, the operation of process 800 can be implemented by a controller or processor of a power transmitter (such as a reference). Figure 13 The operation is implemented by means of devices such as the described apparatus 1300. For the sake of brevity, the operation is described as being performed by the apparatus.

[0069] In block 802, the device transmits a wireless power signal to a power receiver. In block 804, the device receives a first control error value from the power receiver. In block 806, the device adjusts the operating point of the wireless power signal based on the first control error value. In block 808, the device calculates the average baseline power (P) of the wireless power signal after adjusting the operating point. baseline Determine P during the measurement period baseline In frame 810, the device is located at P. calulated The average calculated power (P) of at least one wireless power signal after the measurement period and before receiving the second control error value from the power receiver. calulated ) Calculate P during the measurement period calulated In block 812, the device is at least partially based on P. baseline With P calulated The difference between them is used to control the operation point.

[0070] Figure 9This is a flowchart illustrating an example operation of another process 900 for power control. The operation of process 900 can be implemented by a power transmitter (such as any of the power transmitters 102 described herein). In some embodiments, the operation of process 900 can be implemented by, for example, reference... Figure 13 The operation is implemented by means of devices such as the described apparatus 1300. For the sake of brevity, the operation is described as being performed by the apparatus.

[0071] In block 902, the device transmits a wireless power signal to a power receiver. In block 904, the device adjusts the operating point of the wireless power signal based on a first control error value from the power receiver. In block 906, after adjusting the operating point using the first control error value, the device determines the baseline power (P) of the wireless power signal based on a first measurement value. baseline In blocks 908, 910, 914, and 918, the device controls the operating point based on power transmitter measurements after a first control error value and before a second control error value. In block 910, the device calculates the computed power (P) based on the second measurement at the power transmitter. calulated In box 912, the device is based on P. baseline With P calulated The power error value (P) is calculated from the difference between them. error In box 914, the device is based on P. error Adjust the operation point.

[0072] At decision block 916, the device determines whether a second control error value has been received from the power receiver. If so, process 900 returns to block 904 to adjust the operating point using the second control error value. If it is determined at decision block 916 that the second control error value has not been received, process 700 returns to blocks 908, 910, 912, and 914.

[0073] Figure 10 This is a flowchart illustrating an example operation of process 1000 for overvoltage protection. The operation of process 1000 can be implemented by a controller or processor of a power transmitter (such as any of the power transmitters 102 described herein). In some embodiments, the operation of process 1000 can be implemented by a controller such as a reference... Figure 13 The operation is implemented by means of devices such as the described apparatus 1300. For the sake of brevity, the operation is described as being performed by the apparatus.

[0074] In block 1002, the device transmits a wireless power signal to a power receiver. In block 1004, the device adjusts the operating point of the wireless power signal based on periodic control error (CE) data packets received from the power receiver, the periodic CE data packets including at least a first CE data packet and a second CE data packet. In block 1006, when the load of the power receiver is between the control error interval (t) of the first CE data packet and the second CE data packet... interval When the voltage condition changes during the period, the device mitigates the overvoltage state of the power receiver, wherein mitigating the overvoltage state includes mitigating the baseline power (P) based on the wireless power signal. baseline ) and the calculated power of wireless power signals (P) calulated The operating point is adjusted based on the difference between P and P. baseline Based on the first measurement at the power transmitter following the first CE data packet, and wherein the P calulated Based on P baseline The second measurement was taken at the power transmitter.

[0075] Figure 11 This is a flowchart illustrating an example operation of process 1100 of the power receiver. The operation of process 1100 can be implemented by a controller or processor of the power receiver (such as any of the power receivers 118 described herein). In some embodiments, the operation of process 1100 can be implemented by a controller or processor of a power receiver (such as a reference). Figure 13 The operation is implemented by the device 1300 and other devices described herein. For the sake of brevity, the operation is described as being performed by the device.

[0076] In block 1102, the device transmits power configuration information to the power transmitter, which enables overvoltage protection for the load of the power receiver. In block 1104, the device receives a wireless power signal from the power transmitter. In block 1106, the device periodically transmits control error values ​​to the power transmitter during the power transmission phase.

[0077] Processes 800, 900, 1000, and 1100 are examples of operations. In some embodiments, processes 800, 900, 1000, and 1100 may include other operations or operations different from those described with reference to their respective drawings. For example, in some embodiments, when P errorWhen the voltage exceeds a threshold, the power transmitter can detect an overvoltage state in the power receiver. The power transmitter can transmit an error message to the power receiver or display an error message via the user interface of the power transmitter or the power receiver. In some embodiments, in addition to adjusting the operating point of the wireless power signal, or instead of adjusting the operating point of the wireless power signal, the power transmitter can stop transmitting the wireless power signal in response to detecting an overvoltage state. Other variations are possible within the scope of this disclosure.

[0078] Figure 12 A conceptual flowchart of an example message for transmitting power configuration information is shown according to some aspects of this disclosure. For example, message 1202 can be sent from a power receiver to a power transmitter. In some embodiments, message 1202 may be part of a configuration message or another message. Message 1202 may include a header 1208 and a payload 1204. In some embodiments, header 1208 includes frame control information indicating that 1202 includes power configuration information. In some embodiments, message 1202 may include a preamble 1206 indicating the start of message 1202. Payload 1204 includes one or more information elements 1210, 1212, and 1214.

[0079] Figure 12 Some example information elements 1216 are shown in the figure. For example, power configuration information may include the value of the load capacitance 1218 used in the power receiver, the rated load voltage 1220, the permissible overvoltage level 1222, the time required for the load to reach the permissible overvoltage state 1224 from the rated nominal voltage state when the load is switched from full load to no load, and the information provided by the power transmitter for calculating P. baseline or P calulated The recommended power averaging time is 1226, or any combination of the above information. The load capacitance value determines the rate at which overvoltage may occur at the power receiver.

[0080] The power transmitter can use power configuration information (such as rated voltage, permissible overvoltage, or the time required to reach the permissible overvoltage state from the rated nominal voltage state when the load is switched from full load to no load) to determine the need to perform average P. calulatedThe rate of power change prior to detecting an overvoltage state is used. Additionally or alternatively, the power receiver can be used in a test environment with a standard power transmitter to transmit a recommended power averaging time based on empirical test results. The power receiver can send one or more of the aforementioned power configuration information to the power transmitter to help the power transmitter determine the power averaging time. The power transmitter can set the power averaging time sufficiently small so that it can adequately detect the overvoltage state of the power receiver during a load shedding event. In some embodiments, the power transmitter can determine the power averaging time or an upper limit of the power averaging time based on one or more parameters of its operating parameters and the power configuration information. A power averaging time greater than the upper limit may prevent the power transmitter from being used to prevent overvoltages in the power receiver. In some embodiments, the power transmitter can determine the occurrence of P within a certain period after adjusting the operating point based on a control error value from the power receiver. baseline The measurement period is the time of the measurement. During the occurrence of P... calulated With P baseline When there is a deviation, the power transmitter can determine the time required to move to the new operating point based on the magnitude of the deviation.

[0081] Figure 13 This is a block diagram of an example device for use in a wireless power system. In some embodiments, device 1300 may be a wireless power transmitting device (such as power transmitter 102) as described herein. Device 1300 may include processor 1302 (which may include multiple processors, multiple cores, multiple nodes, or implement multithreading, etc.). Device 1300 may also include memory 1304. Memory 1304 may be any one or more possible implementations of system memory or the computer-readable medium described herein. Device 1300 may also include bus 1306 (such as PCI, ISA, PCI-Express, HyperTransport®, InfiniBand®, NuBus, AHB®, AXI, etc.).

[0082] Device 1300 may include one or more controllers 1308 (such as a TX controller) configured to manage power transmitter circuitry 106. In some embodiments, controller 1308 may be distributed within processor 1302, memory 1304, and bus 1306. Controller 1308 may perform some or all of the operations described herein. For example, controller 1308 may implement reference... Figures 1 to 6 The process described by any one of them or any combination thereof.

[0083] The memory 1304 may include computer instructions executable by the processor 1302 to implement the functions described herein. Any of these functions may be implemented partially (or wholly) in hardware or on the processor 1302. For example, the functions may be implemented by an application-specific integrated circuit (ASIC), logic implemented in the processor 1302, a coprocessor on a peripheral device or card, etc. Furthermore, the implementation may include those not in... Figure 13 Fewer or additional components are shown. Processor 1302, memory 1304, and controller 1308 may be coupled to bus 1306. Although memory 1304 is shown as coupled to bus 1306, memory 1304 may also be coupled to processor 1302.

[0084] Figures 1 to 13 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 or sequential operations, and some operations differently.

[0085] 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 may be made based on the foregoing disclosure or may be obtained from practice of these aspects. While aspects of this disclosure have been described herein by way of various examples, any combination of aspects from any example is also within the scope of this disclosure. The examples in this disclosure are provided for educational purposes. Alternatively, or in addition to the other examples described herein, examples include any combination of the following implementation options (identified as terms for reference).

[0086] Clause 1. A method performed by a power transmitter, the method comprising: transmitting a wireless power signal to a power receiver; receiving a first control error value from the power receiver; adjusting an operating point of the wireless power signal based on the first control error value; and averaging a baseline power (P) after adjusting the operating point. baseline The P of the wireless power signal was determined during the measurement period. baseline ; in the P baseline At least one average calculated power (P) after the measurement period and before receiving the second control error value from the power receiver calculated The P value of the wireless power signal is calculated during the measurement period. calculated ; and at least in part based on the P baseline and the P calculated The difference between them is used to control the operating point.

[0087] Clause 2. The method according to Clause 1, wherein the P is determined baseline Included in the P baseline A first measurement value is obtained during the measurement period, and wherein P is calculated. calculated Included in the P baseline P after the measurement period calculated The second measurement value was obtained during the measurement period.

[0088] Clause 3. The method according to Clause 2, wherein the first measurement and the second measurement include measurements of voltage and current at the DC input of the drive circuit of the power transmitter.

[0089] Clause 4. The method according to Clause 2, wherein the first measurement and the second measurement include measurements of voltage and current at a resonant circuit, the resonant circuit including the primary coil of the power transmitter.

[0090] Clause 5. The method according to any one of Clauses 1 to 4 further comprises: periodically calculating in a plurality of P values ​​before receiving the second control error value. calculated The P of each period in the measurement time period calculated .

[0091] Clause 6. The method according to any one of Clauses 1 to 5 further includes: based on the P baseline and the P calculated The difference between them is used to calculate the power error value (P). error ); and when the P error When the voltage exceeds the threshold, the overvoltage state of the power receiver is detected.

[0092] Clause 7. The method according to Clause 6 further includes transmitting an error message to the power receiver in response to detecting the overvoltage state.

[0093] Clause 8. The method according to Clause 6 or 7 further includes stopping the transmission of the wireless power signal in response to detecting the overvoltage state.

[0094] Clause 9. The method according to any one of Clauses 1 to 8 further comprises: receiving a power request from the power transmitter; and setting a DC output voltage of a power source of the power transmitter based at least in part on the power request, wherein the operating point is further based on the DC output voltage.

[0095] Clause 10. The method according to Clause 9, wherein setting the DC output voltage of the power source includes setting the DC output voltage using a linear scaling calculation of the power request, or setting the DC output voltage to a DC output voltage level corresponding to a range including the power request, wherein the power transmitter supports multiple DC output voltage levels corresponding to multiple ranges of requested power.

[0096] Clause 11. The method according to any one of Clauses 1 to 10, wherein the P baseline Based on the P baseline The average baseline measured power of the first plurality of voltage and current measurements within the measurement period, and wherein P calculated Based on the P calculated The average measured power of the second plurality of voltage and current measurements within the measurement period.

[0097] Clause 12. The method according to any one of Clauses 1 to 11 further comprises: receiving power configuration information from the power receiver; and determining a power averaging time based on the power configuration information, wherein P baseline The measurement period is a first instance of the power averaging time after the operating point has been adjusted based on the first control error value, and wherein P calculated The measurement period is a subsequent instance of the power averaging time.

[0098] Clause 13. The method according to any one of Clauses 1 to 11 further includes: receiving power configuration information from the power receiver; and determining the P based on the power configuration information. baseline The duration of the measurement period, the P calculated The duration of the measurement period or both.

[0099] Clause 14. The method according to Clause 12 or 13, wherein the power configuration information includes: the value of the load capacitance used in the power transmitter, the rated load voltage, the permissible overvoltage level, the time required for the load to reach the permissible overvoltage state from the rated nominal voltage state when the load is switched from full load to no load, the recommended power averaging time transmitted by the power receiver, or any combination thereof.

[0100] Clause 15. The method according to any one of Clauses 1 to 14, based on the control error interval (t) interval ) Receive continuous control error (CE) data packets; and after each CE data packet: adjust the operating point based on the new control error value in the specific CE data packet, and after adjusting the operating point based on the new control error value, determine a new P baselineAnd in determining the new P baseline Subsequently, at least in part based on the new P baseline And the new P calculated The difference between them is in t interval The operation point is controlled during this period.

[0101] Clause 16. The method according to Clause 15, wherein the t interval The range is from 0 ms to 700 ms, and the method further includes: at the t interval During this period, the new P is calculated periodically approximately every 1 to 2 ms. calculated .

[0102] Clause 17. A method performed by a power transmitter, the method comprising: transmitting a wireless power signal to a power receiver; adjusting the operating point of the wireless power signal based on periodic control error (CE) data packets received from the power receiver, the periodic CE data packets including at least a first CE data packet and a second CE data packet; and a control error interval (t) between the first CE data packet and the second CE data packet. interval During this period, when the load on the power receiver changes, the overvoltage state of the power receiver is mitigated, wherein mitigating the overvoltage state includes adjusting the operating point based on the difference between: the baseline power (P) of the wireless power signal based on a first measurement at the power transmitter after the first CE data packet. baseline ), and based on the P baseline The calculated power (P) of the wireless power signal at the second measurement value at the power transmitter is then used to calculate the power of the signal. calculated ).

[0103] Clause 18. The method according to Clause 17, wherein the first measurement includes P baseline The first voltage and current measurements during the measurement period, wherein the second measurement includes the values ​​measured in P. baseline P after the measurement period calculated Second voltage and current measurements during the measurement period.

[0104] Clause 19. The method according to Clause 17 or 18, wherein the first measurement and the second measurement are measured at the DC input of the drive circuit of the power transmitter.

[0105] Clause 20. The method according to Clause 17 or 18, wherein the first measurement and the second measurement are measured at a resonant circuit including the primary coil of the power transmitter.

[0106] Clause 21. A power transmitter comprising: a primary coil configured to transmit a wireless power signal to a power receiver; and a TX controller configured to implement the method of any one of Clauses 1 to 20.

[0107] Clause 22. A method performed by a power receiver, the method comprising: transmitting power configuration information to a power transmitter, the power configuration information enabling overvoltage protection for a load of the power receiver; receiving a wireless power signal from the power transmitter; and, during a power transmission phase, periodically transmitting a control error value to the power transmitter.

[0108] Clause 23. The method according to Clause 22, wherein the power configuration information includes: the value of the load capacitance used in the power transmitter, the rated load voltage, the permissible overvoltage level, the time required for the load to reach the permissible overvoltage state from the rated nominal voltage state when it is switched from full load to no load, the power averaging time for the power transmitter, and the baseline power (P). baseline The duration of the measurement period is used to calculate the power (P). calculated The duration of the measurement period, or any combination thereof.

[0109] Clause 24. The method according to Clause 22 or 23 further includes: wherein the power configuration information indicates the average baseline power (P... baseline P baseline Measurement period, for average calculated power (P) calculated P calculated The measurement period, or both; and wherein the P is mentioned. baseline Measurement period and the P calculated One or more instances of the measurement period occur between two consecutive control error values.

[0110] Clause 25. The method according to Clause 22 further includes: transmitting a power request to the power transmitter, the power request including a request to set the DC output voltage of the power source of the power transmitter based at least in part on the power request.

[0111] Clause 26. The method according to Clauses 22 to 25 further includes: receiving an error message from the power transmitter, the error message indicating that the power transmitter has detected an overvoltage state based on a sudden change in the average power delivered to the power receiver between two consecutive control error values.

[0112] Clause 27. A power receiver comprising: a secondary coil configured to receive a wireless power signal from a power transmitter; and a controller configured to implement the method of any one of Clauses 22 to 26.

[0113] Another innovative aspect of the subject matter described in this disclosure can be implemented as a computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform any of the functions described above.

[0114] Another innovative aspect of the subject matter described in this disclosure can be implemented as a system having means for implementing any of the functions described above.

[0115] 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 from any of the methods described above.

[0116] As used herein, the phrase “at least one” or “one or more” in the list of items refers to any combination of 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.

[0117] The various illustrative components, logic, logic blocks, modules, circuits, operations, and algorithmic processes 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 herein 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 illustrative components, blocks, modules, circuits, and processes described above. The implementation of this functionality in hardware, firmware, or software depends on the specific application and design constraints imposed on the entire system.

[0118] Hardware and data processing apparatuses for implementing the various illustrative components, logic, logic blocks, modules, and circuits described in conjunction with the aspects disclosed herein may be implemented or executed using a general-purpose single-chip or general-purpose 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, discrete hardware components, or any 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. The 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 combined with a DSP core, or any other such configuration. In some embodiments, specific processes, operations, and methods may be performed by circuitry specific to a given function.

[0119] As previously stated, 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 a computer program 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 or control of the operation of a data processing apparatus including components of the device described herein. By way of example and not limitation, such storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage devices, or any other medium that may be used to store program code in the form of instructions or data structures. Combinations of the foregoing should also be included within the scope of storage media.

[0120] Various modifications to the embodiments described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the scope of this disclosure. Therefore, the claims are not intended to limit the embodiments shown herein, but are to be accorded the widest scope consistent with this disclosure, the principles disclosed herein, and the novel features.

[0121] Additionally, the various features described in this specification in the context of 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 claimed in this manner, in some cases one or more features from the claimed combination may be removed from the combination, and the claimed combination may involve sub-combinations or variations thereof.

[0122] Similarly, although the operations are described in a specific order in the accompanying drawings, this should not be construed as requiring these operations to be performed in the specific order shown or sequentially, or to perform all the shown operations to achieve the desired result. Furthermore, the drawings may schematically depict one or more example processes in the form of flowcharts or diagrams. However, other operations not depicted may be incorporated into the schematically shown example processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the shown operations. In some cases, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the above embodiments 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 method performed by a power transmitter, the method comprising: Transmits wireless power signals to the power receiver; Receive a first control error value from the power receiver; The operating point of the wireless power signal is adjusted based on the first control error value; The average baseline power (P) after adjusting the operating point baseline The P of the wireless power signal was determined during the measurement period. baseline ; In the P baseline At least one average calculated power (P) after the measurement period and before receiving the second control error value from the power receiver calculated The P value of the wireless power signal is calculated during the measurement period. calculated ; as well as At least in part based on the P baseline and the P calculated The difference between them is used to control the operating point.

2. The method according to claim 1, in, Determine the P baseline Included in the P baseline The first measurement value was obtained during the measurement period, and Wherein, the calculation of P calculated Included in the P baseline P after the measurement period calculated The second measurement value was obtained during the measurement period.

3. The method of claim 2, wherein the first measurement and the second measurement include voltage and current measurements at the DC input of the drive circuit of the power transmitter.

4. The method of claim 2, wherein the first measurement and the second measurement include voltage and current measurements at a resonant circuit, the resonant circuit including the primary coil of the power transmitter.

5. The method according to any one of claims 1 to 4, further comprising: Before receiving the second control error value, periodically calculate the values ​​in multiple P... calculated The P of each period in the measurement time period calculated .

6. The method according to any one of claims 1 to 5, further comprising: Based on the P baseline and the P calculated The power error value (P) is calculated from the difference between them. error );as well as When the P error When the voltage exceeds the threshold, the overvoltage state of the power receiver is detected.

7. The method of claim 6, further comprising transmitting an error message to the power receiver in response to detecting the overvoltage state.

8. The method of claim 6 or 7, further comprising stopping the transmission of the wireless power signal in response to detecting the overvoltage state.

9. The method according to any one of claims 1 to 8, further comprising: Receive a power request from the power receiver; as well as The DC output voltage of the power source of the power transmitter is set at least in part based on the power request, wherein the operating point is further based on the DC output voltage.

10. The method of claim 9, wherein setting the DC output voltage of the power source includes The DC output voltage is set using a linear scaling calculation based on the power request, or The DC output voltage is set to a DC output voltage level corresponding to the range including the power request, wherein the power transmitter supports multiple DC output voltage levels corresponding to multiple ranges of requested power.

11. The method according to any one of claims 1 to 10, Wherein P baseline Based on the P baseline The average baseline power of the first plurality of voltage and current measurements during the measurement period, and Wherein P calculated Based on the P calculated The average measured power of the second plurality of voltage and current measurements within the measurement period.

12. The method according to any one of claims 1 to 11, further comprising: Receive power configuration information from the power receiver; as well as The power averaging time is determined based on the power configuration information. Wherein P baseline The measurement period is a first instance of the power averaging time after the operating point has been adjusted based on the first control error value, and Wherein P calculated The measurement period is a subsequent instance of the power averaging time.

13. The method according to any one of claims 1 to 11, further comprising: Receive power configuration information from the power receiver; as well as Based on the power configuration information, determine the P baseline The duration of the measurement period, the P calculated The duration of the measurement period or both.

14. The method according to claim 12 or 13, wherein the power configuration information includes: The value of the load capacitor used in the power receiver, Rated load voltage, permissible overvoltage level, The time required for the load to reach the permissible overvoltage state from the rated nominal voltage state when the load is switched from full load to no load. The recommended power averaging time transmitted by the power receiver, or Any combination of the foregoing terms.

15. The method according to any one of claims 1 to 14, According to the control error interval (t) interval ) Receive continuous control error (CE) data packets; and After each CE data group: The operating point is adjusted based on the new control error value in a specific CE data group. After adjusting the operating point based on the new control error value, a new P is determined. baseline ,as well as In determining the new P baseline Subsequently, at least in part based on the new P baseline And the new P calculated The difference between them is in t interval The operation point is controlled during this period.

16. The method of claim 15, wherein the t interval The range is from 0 ms to 700 ms, and the method further includes: In the t interval During this period, the new P is calculated periodically approximately every 1 to 2 ms. calculated .

17. A method performed by a power transmitter, the method comprising: Transmits wireless power signals to the power receiver; The operating point of the wireless power signal is adjusted based on periodic control error (CE) data packets received from the power receiver, wherein the periodic CE data packets include at least a first CE data packet and a second CE data packet; and The control error interval (t) between the first CE data packet and the second CE data packet interval During this period, when the load on the power receiver changes, the overvoltage state of the power receiver is mitigated, wherein mitigating the overvoltage state includes adjusting the operating point based on the difference between the following: The baseline power (P) of the wireless power signal is based on a first measurement taken at the power transmitter after the first CE data packet. baseline ),as well as Based on the P baseline The calculated power (P) of the wireless power signal at the second measurement value at the power transmitter is then used to calculate the power of the signal. calculated ).

18. The method according to claim 17, in, The first measurement includes P baseline The first voltage and current measurements during the measurement period, and Wherein, the second measurement value includes the value in the P baseline P after the measurement period calculated Second voltage and current measurements during the measurement period.

19. The method of claim 17 or 18, wherein the first measurement and the second measurement are measured at the DC input of the drive circuit of the power transmitter.

20. The method of claim 17 or 18, wherein the first measurement and the second measurement are measured at a resonant circuit including the primary coil of the power transmitter.

21. A power transmitter, the power transmitter comprising: A primary coil configured to transmit a wireless power signal to a power receiver; as well as A TX controller configured to implement the method according to any one of claims 1 to 20.

22. A method performed by a power receiver, the method comprising: Power configuration information is transmitted to the power transmitter, which enables overvoltage protection for the load of the power receiver. Receive wireless power signals from the power transmitter; and During the power transmission phase, control error values ​​are periodically transmitted to the power transmitter.

23. The method of claim 22, wherein the power configuration information includes: The value of the load capacitor used in the power receiver, Rated load voltage, permissible overvoltage level, The time required for the load to reach the permissible overvoltage state from the rated nominal voltage state when the load is switched from full load to no load. The power averaging time for the power transmitter. Baseline power (P) baseline The duration of the measurement period. Calculate power (P) calculated The duration of the measurement period, or Any combination of the foregoing terms.

24. The method according to claim 22 or 23, further... include: in, The power configuration information indicates the average baseline power (P) baseline P baseline Measurement period, for average calculated power (P) calculated P calculated The measurement period, or both; and Wherein P baseline Measurement period and the P calculated One or more instances of the measurement period occur between two consecutive control error values.

25. The method according to claims 22 to 24, further comprising: A power request is transmitted to the power transmitter, the power request including a request to set the DC output voltage of the power source of the power transmitter based at least in part on the power request.

26. The method according to claims 22 to 25, further comprising: An error message is received from the power transmitter, indicating that the power transmitter has detected an overvoltage state based on a sudden change in the average power supplied to the power receiver between two consecutive control error values.

27. A power receiver, the power receiver comprising: Secondary coil, which is configured to receive wireless power signals from a power transmitter; as well as A controller configured to implement the method according to any one of claims 22 to 26.

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