Wireless charging dynamic compensation FOD method and apparatus

Abstract

This application discloses a method for dynamic FOD compensation in wireless charging, comprising: measuring the load current of the wireless charging receiver in real time using a sampling resistor; monitoring the operating temperature of the wireless charging receiver using a temperature sensor; obtaining a power loss compensation value by querying a pre-established temperature-current-compensation value correspondence table based on the measured current and temperature values; applying the power loss compensation value to power loss control to keep the power loss within the intermediate value of the protocol's allowable range; and monitoring the compensation effect in real time and dynamically updating the power loss compensation value according to changes in temperature and / or current. This application measures the load current in real time using a sampling resistor, monitors the operating temperature using a temperature sensor, and dynamically adjusts the power loss compensation value according to the operating conditions through real-time monitoring of both temperature and current parameters, ensuring that it always remains within the intermediate value of the protocol's specified range. This avoids charging interruptions caused by false FOD alarms and does not require changes to the existing hardware architecture, thus reducing costs.

Description

Technical Field

[0001] This application relates to the field of wireless charging technology, and in particular to a method and apparatus for dynamic compensation of FOD in wireless charging. Background Technology

[0002] FOD (Foreign Object Detection) is a technology used in wireless charging to prevent accidental objects from causing excessive temperature rise in the system. Wireless charging connects two independent objects using a magnetic field, so there may be foreign objects in the path. If the foreign object is a conductor such as metal, an induced electromotive force will inevitably be generated in the alternating magnetic field, forming an induced current inside the conductor. At this time, the metal acts as a resistor, resulting in high heat generation and potential damage.

[0003] There are two main solutions in the existing technology: one is to increase the size of the receiving coil of the wireless charging receiver (hereinafter referred to as RX device) to give it greater redundancy to be compatible with the wireless charging transmitter (hereinafter referred to as TX device); the other is to adapt to RX devices, such as watches, by customizing matching TX devices, using a magnetic attraction method to prevent displacement of the TX device when charging the RX device. However, due to their small size, the receiving coil of small RX devices cannot be made large, such as charging cases for Bluetooth headsets and watches. These devices are difficult to comply with the Qi standard protocol. Because of the small receiving coil, when using a Qi-certified TX wireless charging dock, slight misalignment or changes in charging current can easily trigger a FOD alarm, thus preventing charging. Customizing matching TX devices would increase costs. Summary of the Invention

[0004] This application provides a method and apparatus for dynamic compensation of FOD in wireless charging.

[0005] According to a first aspect of this application, this application provides a wireless charging dynamic compensation FOD method, comprising:

[0006] The load current of the wireless charging receiver is measured in real time by sampling resistor;

[0007] The operating temperature of the wireless charging receiver is monitored by a temperature sensor.

[0008] Based on the measured current and temperature values, consult the pre-established temperature-current-compensation value correspondence table to obtain the power loss compensation value;

[0009] The power loss compensation value is applied to power loss control to keep the power loss at an intermediate value within the allowable range of the protocol.

[0010] The compensation effect is monitored in real time, and the power loss compensation value is dynamically updated according to changes in temperature and / or current.

[0011] In the method involved in this application, the method for establishing the temperature-current-compensation value correspondence table includes:

[0012] Power loss values ​​were tested in different temperature and current ranges on a standard test platform.

[0013] The power loss value is brought closer to the median value of the range specified in the protocol through compensation;

[0014] The optimal compensation values ​​under each operating condition are recorded to form the temperature-current-compensation value correspondence table.

[0015] In the method involved in this application, the real-time monitoring of the compensation effect and the dynamic updating of the power loss compensation value according to changes in current and / or temperature include:

[0016] The power loss compensation value is updated in real time when the temperature value is detected to cross the temperature range threshold and / or the current value is detected to cross the current range threshold.

[0017] In the method involved in this application, the temperature-current-compensation value correspondence table includes the following:

[0018] The temperature range includes the following three ranges: (0-15℃), (15-35℃), and (35-45℃).

[0019] The current range includes the following three ranges: (0-100mA), (100-300mA), and (300-500mA);

[0020] Each temperature range-current range combination corresponds to the register compensation value and the output voltage level of the wireless charging receiver;

[0021] The output voltage levels include: Load0 corresponds to 7.5V, Load1 corresponds to 6V, and Load2 corresponds to 5V.

[0022] In the method involved in this application, applying the power loss compensation value to power loss control to keep the power loss within an intermediate value of the protocol-allowed range includes:

[0023] The power loss compensation value is applied to power loss control by writing to the compensation value register of the MCU of the wireless charging receiver and / or adjusting the output voltage of the wireless charging receiver.

[0024] For BPP protocol devices, the power loss is kept within the range of 175mW±50mW; for EPP / MPP protocol devices, the power loss is kept near the middle value of the range specified by the protocol.

[0025] According to a second aspect of this application, this application provides a wireless charging dynamic compensation (FOD) device, comprising:

[0026] The current measurement module is used to measure the load current of the wireless charging receiver in real time through a sampling resistor;

[0027] The temperature monitoring module is used to monitor the operating temperature of the wireless charging receiver through a temperature sensor;

[0028] The compensation value query module is used to query a pre-established temperature-current-compensation value correspondence table based on the measured current value and temperature value to obtain the power loss compensation value;

[0029] A power loss processing module is used to apply the power loss compensation value to power loss control, so that the power loss is kept at an intermediate value within the range allowed by the protocol.

[0030] The dynamic adjustment module is used to monitor the compensation effect in real time and dynamically update the power loss compensation value according to changes in temperature and / or current.

[0031] In the device involved in this application, the compensation value query module includes a compensation value preset unit, which is used to test the power loss value in different temperature ranges and current ranges on a standard test platform; to make the power loss value approach the intermediate value of the range specified in the protocol through compensation; and to record the optimal compensation value under each operating condition to form the temperature-current-compensation value correspondence table.

[0032] In the apparatus of this application, the dynamic adjustment module includes:

[0033] The dynamic adjustment unit is used to update the power loss compensation value in real time when the temperature value is detected to cross the temperature range threshold and / or the current value is detected to cross the current range threshold.

[0034] In the apparatus of this application, the power loss processing module includes:

[0035] The first processing unit is used to apply the power loss compensation value to power loss control by writing to the compensation value register of the MCU of the wireless charging receiver and / or adjusting the output voltage of the wireless charging receiver.

[0036] The second processing unit is used to keep the power loss within the range of 175mW±50mW for BPP protocol devices, and to keep the power loss near the middle value of the range specified by the protocol for EPP / MPP protocol devices.

[0037] In the apparatus involved in this application, the apparatus is suitable for:

[0038] Wireless charging receiver devices with a receiving coil length and width both less than 40mm or a receiving coil diameter less than 40mm;

[0039] Wireless charging receiver devices that support Qi standard BPP / EPP / MPP protocols;

[0040] A wireless charging receiver device that allows displacement of the center of the wireless charging transmitter coil.

[0041] Due to the adoption of the above technical solutions, the beneficial effects of this application are as follows:

[0042] The wireless charging dynamic FOD compensation method provided in this application includes: measuring the load current of the wireless charging receiver in real time using a sampling resistor; monitoring the operating temperature of the wireless charging receiver using a temperature sensor; obtaining a power loss compensation value by querying a pre-established temperature-current-compensation value correspondence table based on the measured current and temperature values; applying the power loss compensation value to power loss control to keep the power loss within the intermediate value of the protocol's allowable range; and monitoring the compensation effect in real time and dynamically updating the power loss compensation value according to changes in temperature and / or current. This application measures the load current in real time using a sampling resistor, monitors the operating temperature using a temperature sensor, establishes a current-temperature-compensation value correspondence table, and dynamically adjusts the power loss compensation value according to the operating conditions through real-time monitoring of both temperature and current parameters, ensuring it remains within the intermediate value of the protocol's specified range. This avoids charging interruptions caused by false FOD alarms and does not require changes to the existing hardware architecture, thus reducing costs. Attached Figure Description

[0043] Figure 1 Circuit diagram for wireless charging;

[0044] Figure 2 A schematic diagram illustrating the power loss of a BPP protocol device tested on a standard wireless charging device.

[0045] Figure 3 This is a charging diagram of a wireless charger provided in an embodiment of this application;

[0046] Figure 4 A flowchart of one implementation of the method provided in this application embodiment;

[0047] Figure 5 A flowchart of another implementation of the method provided in the embodiments of this application;

[0048] Figure 6 A flowchart of another embodiment of the method provided in this application;

[0049] Figure 7A schematic diagram of the program modules of the apparatus provided in one embodiment of this application;

[0050] Figure 8 This is a schematic diagram of the program modules of the detection device according to an embodiment of this application in another implementation. Detailed Implementation

[0051] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0052] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0053] The serial numbers assigned to components in this article, such as "first" and "second", are used only to distinguish the objects being described and have no sequential or technical meaning.

[0054] Furthermore, the technical features and solutions described herein can be combined in any suitable manner in one or more embodiments. It will be readily understood by those skilled in the art that the steps or order of operations related to the embodiments provided herein can also be changed. Therefore, any order in the drawings and embodiments is for illustrative purposes only and does not imply a requirement to follow a particular order, unless explicitly stated otherwise.

[0055] This application is based on power loss (hereinafter referred to as P). LOSS Methods to compensate for FOD include, for example, the BPP protocol stipulates that P LOSS The range is within 350mW. The EPP protocol specifies P... PT -P PR ≤ Limit ΔP.

[0056] There are several detection methods for FOD. The Qi protocol only specifies the temperature rise of the wireless charging receiver RX. The certification laboratory test stipulates that the RX temperature rise must not exceed 12°C of the ambient temperature, but it does not specify which method must be used to achieve this. The commonly used solutions are shown in Table 1:

[0057]

[0058] Table 1. Schematic Diagram of Agreement Scheme Content

[0059] like Figure 1 As shown, the TX end calculates P LOSS To determine whether FOD has occurred, where P LOSS = P PT -P PR .

[0060] P PT = P In- P PTLoss P In Equal to input power, P PTLoss This includes all necessary transmission loss power at the TX end, including but not limited to the equivalent impedance of the primary coil and capacitor, power consumption generated by the inverter circuit and PCB traces, eddy current losses generated by metal devices at the TX end, and system power consumption.

[0061] P PR =P Out +P PRLoss P Out Equal to output power, P PRLoss This includes all necessary transmission loss power at the RX end, including but not limited to the equivalent impedance of the secondary coil and capacitor, power consumption generated by the rectifier circuit and PCB traces, eddy current losses generated by the metal components at the RX end, and system power consumption.

[0062] Using P LOSS The reliability of this method for detecting foreign objects (FOD) largely depends on the accuracy of the power reported by the TX and RX terminals. Considering unmeasurable factors, such as the influence of degrees of freedom (the power reported by TX and RX under different loads has an offset, and some energy dissipates into the air), to prevent false FOD reports from TX, the power reported by RX is typically... received =P PR +P Δ , where P Δ As compensation for the aforementioned factors.

[0063] This indicates that when there are no foreign objects on the TX surface, the power reported by the RX is always equal to or greater than the transmission power P of the TX. PT Large. Depending on the output power, P Δ They are also different; their value is generally taken as 5% of the maximum output power, and the recommended P in Qi is...Δ The values ​​are shown in Table 2:

[0064]

[0065] Table 2 Power Loss Table

[0066] System deviation is related to the transmission power level. Ideally, the calibration should be performed in segments across the entire range of output power. However, since this method is difficult to implement, a compromise is adopted: during the calibration phase, the TX and RX devices will determine their own output and receive power according to light and heavy load conditions. Based on these two load conditions, the TX can use the following linear interpolation method to calibrate the output or receive power.

[0067]

[0068] Among them, P Cal For the calibrated transmission power, P Rx For received power, P Tx Let be the transmission power, and a and b be coefficients.

[0069]

[0070] in, For the transmission power under heavy load, For the receiving power under heavy load, For the receiving power under light load, This refers to the transmit power under light load.

[0071] As mentioned above, the power calibration method involves the TX and RX devices determining their own output and receive power based on light and heavy load conditions, compensating for a fixed value P. Δ This compensation scheme has significant redundancy when applied to RX devices with large coil sizes. However, in smaller products, the smaller coil size makes it more susceptible to changes in load current, temperature, and displacement. Therefore, it is necessary to dynamically compensate P based on real-time changes in load current and temperature. LOSS .

[0072] like Figure 2 As shown, for the BPP protocol RX device, when the load current changes, before 00:20 and after 01:10, its PΔ (Pt+350mW) has exceeded the protocol range (the normal Pr curve is between Pt and Pt+350mW). At this time, the TX end will report a FOD abnormality.

[0073] BPP protocol device P LOSSThe range is 0 to 350mW. Pt is the transmitting power and Pr is the receiving power. The protocol stipulates that Pr - Pt should be ≤ 350mW. In the image, Pr is already greater than Pt + 350mW, so Pr needs to be compensated back and controlled within the range of Pt + 350mW. Ideally, it should be controlled around Pt + 175mW, which is closest to the center value.

[0074] Figure 3 The wireless charging schematic diagram provided in this application embodiment includes three parts: TX, RX, and Load. TX: The wireless charging transmitter, used to transmit wireless charging signals, mainly includes three parts: MCU3 (microprocessor, the control unit of the wireless charging transmitter), a control circuit power bridge (used to convert DC power signals into AC power signals), and coil 1 (to transmit AC power signals). RX: The wireless charging receiver, receiving the wireless charging signals transmitted from the TX end and converting the AC signals into DC signals, mainly includes three parts: MCU2 (microprocessor, the control unit of the wireless charging receiver), a rectifier circuit (rectifier bridge, used to convert AC power signals into DC power signals), and coil 2 (used to receive AC power signals from the TX end). Load: The load end, realizing the functions of charging the battery and supplying power to the load end system. The MCU1 of the Load end can communicate with the MCU2 of the RX end; the MCU2 of the RX end can be a separate unit or an integrated circuit chip integrated with the rectifier circuit of the RX end.

[0075] like Figure 4 As shown in the embodiments of this application, one implementation of the wireless charging dynamic compensation FOD method includes the following steps:

[0076] Step 101: Measure the load current of the wireless charging receiver in real time using a sampling resistor.

[0077] like Figure 3 As shown, the current at the load terminal under various operating conditions is measured by sampling resistor. There is a voltage difference across sampling resistor RS. The ADC of MCU1 calculates the voltage value. Current (I) = Voltage (V) / Sampling resistor (R).

[0078] Step 102: Monitor the operating temperature of the wireless charging receiver using a temperature sensor.

[0079] The operating temperature of the wireless charging receiver is monitored by a temperature sensor when different currents pass through it.

[0080] Step 103: Based on the measured current and temperature values, query the pre-established temperature-current-compensation value correspondence table to obtain the power loss compensation value.

[0081] The eddy current loss of the coil under different temperature conditions can be calculated through testing. The procedure involves setting a fixed current at the load end and then measuring P. LOSS Based on actual test results, current and temperature ranges were categorized, and a temperature-current-compensation value correspondence table was established. Different ranges compensate for different P values. LOSS The load-side MCU samples the current temperature and current values ​​and writes the corresponding compensation values ​​into the RX-side MCU via communication.

[0082] Step 104: Apply the power loss compensation value to the power loss control to keep the power loss within the middle of the range allowed by the protocol.

[0083] The compensation methods can specifically include three types: First, the MCU inside the RX terminal has a compensation value register, which can be written to the register; second, the output voltage of the RX terminal is adjusted to control the output efficiency of the wireless charging receiver and thus affect the P. LOSS Thirdly, a combination of the above two methods. Compensation can be achieved through register writing or adjustment at the RX terminal, forming a closed-loop control.

[0084] Step 105: Monitor the compensation effect in real time and dynamically update the power loss compensation value according to changes in temperature and / or current.

[0085] The compensation effect is monitored in real time, and the power loss compensation value is dynamically updated according to the changes in temperature and / or current.

[0086] This application does not rely on device information at the TX end. It queries the power loss compensation value through temperature and load current, enabling the RX device to maintain P under different temperature and current scenarios. LOSS In its optimal state, device compatibility is improved.

[0087] like Figure 5 As shown, the method for establishing the temperature-current-compensation value correspondence table in step 103 may specifically include the following steps:

[0088] Step 1031: Test the power loss values ​​in different temperature and current ranges on a standard test platform;

[0089] Step 1032: Compensate to bring the power loss value closer to the median value of the range specified in the protocol;

[0090] Step 1033: Record the optimal compensation value under each operating condition to form the temperature-current-compensation value correspondence table.

[0091] In one implementation, establishing a temperature-current-compensation value correspondence table may specifically include the following steps:

[0092] 1. Based on the product's required charging temperature range and charging current range, for example, a temperature range of 0–45℃ and a charging current range of 0–500mA. Within this temperature range, test different charging currents on a wireless charging standard testing platform. Different P values ​​can be obtained through this platform. LOSS value.

[0093] 2. If the device being tested is a BPP protocol device, it should be tested according to the P protocol specified by QI. LOSS The range is 0–350mW, with a center value of 175mW. If the value exceeds this range, a FOD alarm will occur at the TX end. Statistically analyze the data from point 1 and observe its P... LOSS If the distribution deviates significantly from the center value of 175mW, compensation is used to bring it closer to the center value. This ensures greater margin when the charging device moves up, down, left, and right, guaranteeing compatibility.

[0094] 3. To compensate to near the center value, different compensation values ​​need to be written to the wireless charging standard test platform. The compensated P LOSS The value closest to the center value is used to write the compensation value into the charging logic of the corresponding temperature and current ranges, and then saves it to the MCU or other devices that can store parameters. This way, the temperature range, charging current range, and P... LOSS The compensation values ​​then form a corresponding relationship among the three. The compensation values ​​for other temperature and current ranges are obtained in the same way.

[0095] 4. The compensation method can be a fixed value, an adjustment of the output voltage at the RX terminal, or a combination of both.

[0096] 5. The product's temperature can be read using a temperature sensor, and the charging current can be read using a sampling resistor. The control unit, such as an MCU, queries the corresponding P based on the current temperature and charging current values. LOSS The compensation value is written to the wireless charging chip at the RX end via communication.

[0097] In one implementation, the temperature-current-compensation value correspondence table includes the following:

[0098] The temperature range includes the following three intervals: (0-15℃), (15-35℃), and (35-45℃).

[0099] The current range includes the following three ranges: (0-100mA), (100-300mA), and (300-500mA);

[0100] Each temperature range-current range combination corresponds to a specific register compensation value and RX terminal output voltage level;

[0101] The output voltage levels at the RX terminal are: Load0 corresponds to 7.5V, Load1 corresponds to 6V, and Load2 corresponds to 5V.

[0102] The temperature range can be divided according to the battery's charging specifications, and can also be adjusted as needed, such as adjusting the number of temperature ranges or the temperature range of each range. The current range can also be adjusted as needed, such as adjusting the number of current ranges or the current range of each current range. The RX terminal output voltage levels can also include other voltage values.

[0103] Please refer to Table 3 for details:

[0104]

[0105] Table 3. Correspondence between Temperature, Current, and Compensation Value

[0106] In one implementation, step 105 may specifically include:

[0107] When a temperature value is detected to cross a temperature range threshold, and / or a current value is detected to cross a current range threshold, the power loss compensation value is updated in real time.

[0108] According to the interval refresh, for example, if the temperature remains constant and the charging current drops from the 100-300mA range to the 0-100mA range, crossing the compensation interval, the power loss compensation value needs to be refreshed. During the charging process, in the constant voltage charging stage (CV stage), the charging current decreases slowly. For example, if the charging current is 1C charging (550mA), the charging current range in the CV interval is 550mA to 0mA. In the CV stage, the battery voltage remains constant, and the charging current gradually decreases. The charging current during the charging process will vary with changes in ambient temperature or the charging stage (CV stage), and different charging currents correspond to different P... LOSS They are not the same. Therefore, it is necessary to perform graded compensation for charging temperature and current. When the MCU at the load end detects that the temperature or charging current exceeds the current grade, it performs P... LOSS Compensation switch.

[0109] like Figure 6 As shown, step 104 may specifically include the following steps:

[0110] Step 1041: Apply the power loss compensation value to power loss control by writing to the compensation value register of the MCU of the wireless charging receiver and / or adjusting the output voltage of the wireless charging receiver.

[0111] Based on wireless charging efficiency, charging temperature rise control, and system stability, the RX terminal output voltage is categorized into three levels: light load, medium load, and heavy load. These three levels correspond to charging currents of 0-100mA, 100-300mA, and 300-500mA, respectively, and corresponding to RX terminal output voltages of 7.5V, 6V, and 5V. The lower the load-side charging current, the lower the charging efficiency and the greater the actual power loss. Therefore, it is necessary to adjust the RX terminal output voltage to compensate for the power loss. Since the load-side current remains constant, increasing the voltage increases the power at the RX terminal. Power consumption = voltage * current. By adjusting the RX terminal output voltage on a standard wireless charging test platform, the power loss is adjusted to near the center value. Because the product must consider charging efficiency and charging temperature rise control, the compensated power loss may not necessarily be near the center value. When the compensated power loss is not near the center value, it can be combined with register compensation values ​​applied to the RX terminal.

[0112] Step 1042: For BPP protocol devices, keep the power loss within the range of 175mW ± 50mW. For EPP / MPP protocol devices, keep the power loss near the middle value of the range specified by the protocol, specifically within the range of the middle value ± 50mW.

[0113] like Figure 7 As shown in the embodiment of this application, the wireless charging dynamic compensation FOD device includes, in one embodiment, a current sampling circuit 710, a temperature sensing module 720, a compensation value query module 730, a power loss processing module 740, and a dynamic adjustment module 750.

[0114] The current sampling circuit 710 is used to measure the load current of the wireless charging receiver in real time through the sampling resistor.

[0115] like Figure 3 As shown, the current at the load terminal under various operating conditions is measured by sampling resistor. There is a voltage difference across sampling resistor RS. The ADC of MCU1 calculates the voltage value. Current (I) = Voltage (V) / Sampling resistor (R).

[0116] Temperature sensing module 720 is used to monitor the operating temperature of the wireless charging receiver via a temperature sensor.

[0117] The operating temperature of the wireless charging receiver is monitored by a temperature sensor when different currents pass through it.

[0118] The compensation value query module 730 is used to query a pre-established temperature-current-compensation value correspondence table based on the measured current value and temperature value to obtain the power loss compensation value.

[0119] The eddy current loss of the coil under different temperature conditions can be calculated through testing. The procedure involves setting a fixed current at the load end and then measuring P. LOSS Based on actual test results, current and temperature ranges were categorized, and a temperature-current-compensation value correspondence table was established. Different ranges compensate for different P values. LOSS The load-side MCU samples the current temperature and current values ​​and writes the corresponding compensation values ​​into the RX-side MCU via communication.

[0120] The power loss processing module 740 is used to apply the power loss compensation value to the power loss control, so that the power loss is kept at the middle value of the protocol-allowed range.

[0121] The compensation methods can specifically include three types: First, the MCU inside the RX terminal has a compensation value register, which can be written to the register; second, the output voltage of the RX terminal is adjusted to control the output efficiency of the wireless charging receiver and thus affect the P. LOSS Thirdly, a combination of the above two methods. Compensation can be achieved through register writing or adjustment at the RX terminal, forming a closed-loop control.

[0122] The dynamic adjustment module 750 is used to monitor the compensation effect in real time and dynamically update the power loss compensation value according to changes in current or temperature.

[0123] The compensation effect is monitored in real time, and the power loss compensation value is dynamically updated according to the changes in temperature and / or current.

[0124] like Figure 8 As shown in the embodiment of this application, another implementation of the wireless charging dynamic compensation FOD device includes a current sampling circuit 710, a temperature sensing module 720, a compensation value query module 730, a power loss processing module 740, and a dynamic adjustment module 750.

[0125] The current sampling circuit 710 is used to measure the load current of the wireless charging receiver in real time through the sampling resistor;

[0126] Temperature sensing module 720 is used to monitor the operating temperature of the wireless charging receiver through a temperature sensor.

[0127] The compensation value query module 730 is used to query a pre-established temperature-current-compensation value correspondence table based on the measured current value and temperature value to obtain the power loss compensation value;

[0128] The power loss processing module 740 is used to apply the power loss compensation value to the power loss control so that the power loss is kept at the middle value of the protocol-allowed range.

[0129] The dynamic adjustment module 750 is used to monitor the compensation effect in real time and dynamically update the power loss compensation value according to changes in current or temperature.

[0130] The compensation value query module 730 may include a compensation value preset unit 731, which is used to test the power loss value in different temperature and current ranges on a standard test platform; to make the power loss value approach the intermediate value of the range specified in the protocol through compensation; and to record the optimal compensation value under each operating condition to form a temperature-current-compensation value correspondence table.

[0131] In one implementation, establishing a temperature-current-compensation value correspondence table may specifically include the following steps:

[0132] 1. Based on the product's required charging temperature range and charging current range, for example, a temperature range of 0–45℃ and a charging current range of 0–500mA. Within this temperature range, test different charging currents on a wireless charging standard testing platform. Different P values ​​can be obtained through this platform. LOSS value.

[0133] 2. If the device being tested is a BPP protocol device, it should be tested according to the P protocol specified by QI. LOSS The range is 0–350mW, with a center value of 175mW. If the value exceeds this range, a FOD alarm will occur at the TX end. Statistically analyze the data from point 1 and observe its P... LOSS If the distribution deviates significantly from the center value of 175mW, compensation is used to bring it closer to the center value. This ensures greater margin when the charging device moves up, down, left, and right, guaranteeing compatibility.

[0134] 3. To compensate to near the center value, different compensation values ​​need to be written to the wireless charging standard test platform. The compensated P LOSS The value closest to the center value is used to write the compensation value into the charging logic of the corresponding temperature and current ranges, and then saves it to the MCU or other devices that can store parameters. This way, the temperature range, charging current range, and P... LOSS The compensation values ​​then form a corresponding relationship among the three. The compensation values ​​for other temperature and current ranges are obtained in the same way.

[0135] 4. The compensation method can be a fixed value, an adjustment of the output voltage at the RX terminal, or a combination of both.

[0136] 5. The product's temperature can be read using a temperature sensor, and the charging current can be read using a sampling resistor. The control unit, such as an MCU, queries the corresponding P based on the current temperature and charging current values. LOSS The compensation value is written to the wireless charging chip at the RX end via communication.

[0137] In one implementation, the temperature-current-compensation value correspondence table includes the following:

[0138] The temperature range includes the following three intervals: (0-15℃), (15-35℃), and (35-45℃).

[0139] The current range includes the following three ranges: (0-100mA), (100-300mA), and (300-500mA);

[0140] Each temperature range-current range combination corresponds to a specific register compensation value and RX terminal output voltage level;

[0141] The output voltage levels at the RX terminal are: Load0 corresponds to 7.5V, Load1 corresponds to 6V, and Load2 corresponds to 5V.

[0142] The temperature range can be divided according to the battery's charging specifications, and can also be adjusted as needed, such as adjusting the number of temperature ranges or the temperature range of each range. The current range can also be adjusted as needed, such as adjusting the number of current ranges or the current range of each current range. The RX terminal output voltage levels can also include other voltage values.

[0143] For details of the temperature-current-compensation value correspondence table, please refer to Table 3.

[0144] The dynamic adjustment module 750 may include a dynamic adjustment unit 751, which is used to update the power loss compensation value in real time when the temperature value is detected to cross the temperature range threshold or the current value is detected to cross the current range threshold.

[0145] In one embodiment, the power loss processing module 740 may include a first processing unit 741 and a second processing unit 742.

[0146] The first processing unit 741 is used to apply the power loss compensation value to power loss control by writing the compensation value register of the MCU of the wireless charging receiver and / or adjusting the output voltage of the wireless charging receiver.

[0147] Based on wireless charging efficiency, charging temperature rise control, and system stability, the RX terminal output voltage is categorized into three levels: light load, medium load, and heavy load. These three levels correspond to charging currents of 0-100mA, 100-300mA, and 300-500mA, respectively, and corresponding to RX terminal output voltages of 7.5V, 6V, and 5V. The lower the load-side charging current, the lower the charging efficiency and the greater the actual power loss. Therefore, it is necessary to adjust the RX terminal output voltage to compensate for the power loss. Since the load-side current remains constant, increasing the voltage increases the power at the RX terminal. Power consumption = voltage * current. By adjusting the RX terminal output voltage on a standard wireless charging test platform, the power loss is adjusted to near the center value. Because the product must consider charging efficiency and charging temperature rise control, the compensated power loss may not necessarily be near the center value. When the compensated power loss is not near the center value, it can be combined with register compensation values ​​applied to the RX terminal.

[0148] The second processing unit 742 is used to keep the power loss within the range of 175mW±50mW for BPP protocol devices and to keep the power loss near the middle value of the range specified by the protocol for EPP / MPP protocol devices, specifically within the range of the middle value±50mW.

[0149] The wireless charging dynamic compensation FOD device provided in this application embodiment is applicable to the following wireless charging receiver devices:

[0150] Wireless charging receiver devices with a receiving coil length and width both less than 40mm or a receiving coil diameter less than 40mm;

[0151] Wireless charging receiver devices that support Qi standard BPP / EPP / MPP protocols;

[0152] A wireless charging receiver device that allows displacement of the center of the wireless charging transmitter coil.

[0153] Those skilled in the art will understand that all or part of the steps of the various methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, which may include: read-only memory, random access memory, disk or optical disk, etc.

[0154] The above description, in conjunction with specific embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. Those skilled in the art to which this application pertains can make several simple deductions or substitutions without departing from the concept of this application.

Claims

1. A wireless charging dynamic compensation FOD method, characterized in that, The application comprises: measuring the load current of the wireless charging receiver in real time through a sampling resistor; monitoring the working temperature of the wireless charging receiver through a temperature sensor; querying a pre-established temperature-current-compensation value correspondence table according to the measured current value and temperature value to obtain a power loss compensation value; applying the power loss compensation value to power loss control to keep the power loss within the middle value of the protocol allowed range; monitoring the compensation effect in real time and dynamically updating the power loss compensation value according to the changes in temperature and / or current; the establishment method of the temperature-current-compensation value correspondence table comprises: testing the power loss values in different temperature intervals and current intervals on a standard test platform; compensating to make the power loss value close to the middle value of the protocol specified range; recording the optimal compensation value under each working condition to form the temperature-current-compensation value correspondence table.

2. The method of claim 1, wherein, The real-time monitoring of the compensation effect and the dynamic updating of the power loss compensation value according to the changes in current and / or temperature comprises: updating the power loss compensation value in real time when the temperature value crosses the temperature interval threshold and / or the current value crosses the current interval threshold.

3. The method of claim 1, wherein, The temperature-current-compensation value correspondence table comprises the following contents: The temperature interval comprises the following three intervals: (0-15℃], (15-35℃] and (35-45℃]; The current interval comprises the following three intervals: (0-100mA], (100-300mA] and (300-500mA]; Each temperature interval-current interval combination corresponds to a register compensation value and an output voltage level of the wireless charging receiver; The output voltage level comprises: Load0 corresponds to 7.5V, Load1 corresponds to 6V and Load2 corresponds to 5V.

4. The method of claim 1, wherein, The application of the power loss compensation value to power loss control to keep the power loss within the middle value of the protocol allowed range comprises: applying the power loss compensation value to power loss control by writing the compensation value register of the MCU of the wireless charging receiver and / or adjusting the output voltage of the wireless charging receiver; for BPP protocol equipment, keeping the power loss within the range of 175mW±50mW, and for EPP / MPP protocol equipment, keeping the power loss near the middle value of the protocol specified range.

5. A wireless charging dynamic compensation FOD device, characterized in that, The application comprises: a current measurement module for measuring the load current of the wireless charging receiver in real time through a sampling resistor; a temperature monitoring module for monitoring the working temperature of the wireless charging receiver through a temperature sensor; a compensation value query module for querying a pre-established temperature-current-compensation value correspondence table according to the measured current value and temperature value to obtain a power loss compensation value; a power loss processing module for applying the power loss compensation value to power loss control to keep the power loss within the middle value of the protocol allowed range; a dynamic adjustment module for monitoring the compensation effect in real time and dynamically updating the power loss compensation value according to the changes in temperature and / or current; The compensation value query module comprises a compensation value preset unit configured to test power loss values in different temperature intervals and current intervals on a standard test platform; The power loss values are compensated to approach the middle value in the range specified by the protocol; The optimal compensation values in each working condition are recorded to form the temperature-current-compensation value correspondence table.

6. The apparatus of claim 5, wherein, The dynamic adjustment module comprises: A dynamic adjustment unit configured to update the power loss compensation value in real time when detecting that the temperature value crosses the temperature interval threshold and / or detecting that the current value crosses the current interval threshold.

7. The apparatus of claim 5, wherein, The power loss processing module comprises: A first processing unit configured to apply the power loss compensation value to power loss control by writing the compensation value register of the MCU of the wireless charging receiver and / or adjusting the output voltage of the wireless charging receiver; A second processing unit configured to keep the power loss within the range of 175mW±50mW for BPP protocol equipment and within the range of the middle value specified by the protocol for EPP / MPP protocol equipment.

8. The apparatus of claim 5, wherein, The device is suitable for: Wireless charging receiver equipment with a receiving coil length and width of less than 40mm or a receiving coil diameter of less than 40mm; Wireless charging receiver equipment supporting QI standard BPP / EPP / MPP protocol; Wireless charging receiver equipment allowing displacement of the wireless charging transmitter coil center.

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