Foreign matter detection parameter calibration method and system for wireless charging

Abstract

The invention discloses a foreign matter detection parameter calibration method and system for wireless charging. According to the foreign matter detection parameter calibration method for wireless charging, it is confirmed that a transmitting coil of a charger and a receiving coil of a device to be charged are adjusted to preset relative positions; adjusting the transmitting power of the transmitting coil at the preset relative position; power loss values are calculated to obtain the power loss values calibrated at the preset relative position under different transmitting power conditions, and the power loss values serve as foreign matter detection parameters. Thus, the accuracy and sensitivity of wireless charging foreign matter detection are improved through self-adaptive calibration of the power loss values under different transmitting power conditions in different coupling states, the false alarm rate is remarkably reduced, and therefore the user experience and the charging safety are improved; the problems of inaccurate detection, high false alarm rate, poor compatibility and the like caused by a fixed threshold value or lack of dynamic self-adaptive capability are effectively solved.

Description

Technical Field

[0001] This application relates to wireless charging positioning, specifically to a method and system for calibrating foreign object detection parameters for wireless charging. Background Technology

[0002] With the rapid development and widespread adoption of wireless charging technology, it has brought unprecedented convenience to users. However, during radio wave transmission, foreign objects (FODs) placed between the device and the charger may generate heat due to eddy current effects, potentially posing a safety hazard. Therefore, an efficient and accurate FOD detection mechanism is an indispensable key component of a wireless charging system, designed to ensure charging safety and protect the user experience.

[0003] Currently, the wireless charging field commonly employs foreign object detection methods based on power loss. This involves monitoring the difference between the transmitting power of the charger's transmitting coil and the receiving power of the receiving coil of the device being charged to determine the presence of a foreign object. Normally, a wireless charging system presets an allowable power loss threshold; once the actual power loss exceeds this threshold, a foreign object is detected, and charging is stopped. However, this strategy faces numerous challenges in practical applications.

[0004] Specifically, due to the large number of wireless charging receiver coil (RX) suppliers on the market, each with different built-in coil designs, internal compensation values, and coupling characteristics with the transmitting coil, the inherent power loss values ​​of different devices being charged vary even under ideal conditions where no foreign objects are present. To ensure effective detection of various metallic foreign objects, the transmitting coil (TX) often needs to set a relatively strict allowable power loss threshold. While this strict setting improves the safety margin, it inevitably leads to some receiver coils triggering false foreign object alarms during normal charging. Once a false alarm occurs, the wireless charging process will be abnormally interrupted, which not only causes unnecessary inconvenience and complaints for users, seriously affecting the user experience, but may even raise questions about the reliability of the wireless charging system.

[0005] Given the aforementioned issues, existing technologies have significant shortcomings in calibrating foreign object detection parameters. Traditional calibration methods often employ fixed or finite model parameter estimations, making it difficult to adapt to the rapidly changing actual charging environment and the diverse range of devices to be charged. They cannot dynamically and accurately identify and compensate for the inherent differences between different devices, thus making it difficult to achieve an ideal balance between foreign object detection sensitivity and false alarm rate. Especially in complex application scenarios, there is a lack of an effective method that can perform real-time or online adaptive calibration based on the actual coupling state and the characteristics of the device to be charged, to ensure accurate foreign object identification while significantly reducing the false alarm rate, thereby improving the overall performance of the wireless charging system and user satisfaction. Summary of the Invention

[0006] To overcome the limitations of the prior art, according to one aspect of this application, a method for calibrating foreign object detection parameters for wireless charging is provided, comprising:

[0007] Confirm that the charger's transmitting coil and the device's receiving coil are adjusted to the preset relative positions;

[0008] Adjust the transmission power of the transmitting coil at the preset relative position;

[0009] Calculate the power loss value to obtain the power loss value under different transmission power conditions calibrated at the preset relative position, wherein the power loss value is used as a foreign object detection parameter.

[0010] According to one embodiment of the foreign object detection parameter calibration method for wireless charging described in this application, adjusting the transmission power of the transmitting coil at the preset relative position includes: gradually increasing the transmission power of the transmitting coil at the preset relative position.

[0011] According to one embodiment of the foreign object detection parameter calibration method for wireless charging described in this application, the foreign object detection parameter calibration method for wireless charging further includes: fitting the power loss value calibrated at different transmission powers at the same preset relative position to obtain the transmission power-power loss value calibration curve corresponding to the preset relative position.

[0012] According to one embodiment of the foreign object detection parameter calibration method for wireless charging described in this application, the foreign object detection parameter calibration method for wireless charging further includes: confirming that the transmitting coil of the charger and the receiving coil of the device to be charged are adjusted to another preset relative position;

[0013] Calculate the power loss value to obtain the power loss value under different transmission power conditions calibrated at another preset relative position.

[0014] According to one embodiment of the foreign object detection parameter calibration method for wireless charging described in this application, confirming that the transmitting coil of the charger and the receiving coil of the device to be charged are adjusted to a preset relative position includes: confirming that the transmitting coil of the charger is adjusted to a preset transmitting position and / or the receiving coil of the device to be charged is adjusted to a preset receiving position.

[0015] In one embodiment of the foreign object detection parameter calibration method for wireless charging according to this application, the preset transmission position is obtained through a self-learning mode.

[0016] According to one embodiment of the foreign object detection parameter calibration method for wireless charging described in this application, obtaining the preset transmission position through a self-learning mode includes: adjusting the position of the transmitter coil of the charger, and determining the energy intensity received by the test receiver coil when the transmitter coil is in each position; taking the position of the transmitter coil when the energy intensity received by the receiver coil is the maximum as the preset transmission position.

[0017] According to another aspect of this application, a foreign object detection parameter calibration system for wireless charging is also proposed, comprising:

[0018] The position confirmation unit is used to confirm that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to a preset relative position;

[0019] A transmission power control unit is used to adjust the transmission power of the transmission coil at the preset relative position;

[0020] A power loss value calculation unit is used to calculate the power loss value to obtain the power loss value under different transmission power conditions calibrated at the preset relative position, wherein the power loss value is used as a foreign object detection parameter.

[0021] According to one embodiment of the foreign object detection parameter calibration system for wireless charging described in this application, the transmission power control unit is further configured to gradually increase the transmission power of the transmission coil at the preset relative position.

[0022] According to one embodiment of the foreign object detection parameter calibration system for wireless charging described in this application, the foreign object detection parameter calibration system for wireless charging further includes: a fitting unit, used to fit the power loss value calibrated at different transmission powers at the same preset relative position, so as to obtain the transmission power-power loss value calibration curve corresponding to the preset relative position.

[0023] The main purpose of the foreign object detection parameter calibration method for wireless charging provided in this application is to achieve adaptive calibration of foreign object detection parameters, so that the wireless charging system can accurately determine whether there is abnormal power loss during the actual charging process. This significantly reduces the occurrence of false FOD while ensuring that metal foreign objects are correctly identified, and greatly improves the user experience.

[0024] Specifically, the core concept of this application lies in breaking through the limitations of traditional fixed thresholds or rough estimations. Instead, it establishes a foreign object detection parameter system that is highly matched to the characteristics of the device being charged and dynamically adapts to environmental changes by performing multi-power point calibration on the charger and the device to be charged at specific locations. Specifically, the foreign object detection parameter calibration method for wireless charging in this application first aims to determine at least one preset relative position, such as a preset optimal relative coupling position, to ensure optimal energy transfer efficiency between the charger's transmitting coil and the receiving coil of the device being charged. Based on this, the transmitting power of the transmitting coil is actively adjusted, and under different power conditions, the loss value of the receiving power of the device being charged relative to the transmitting power is accurately calculated. These loss values ​​are not simple data points, but are used as key foreign object detection parameters because they are obtained under ideal coupling and a pure state free from foreign object interference, and can truly reflect the inherent characteristics of the device being charged.

[0025] The foreign object detection parameter calibration method for wireless charging provided in this application has significant technical advantages. First, by determining a preset relative position and calibrating at multiple transmission power points within that position, this method can obtain accurate power loss values ​​for a specific device under different power conditions as foreign object detection parameters. This frees the wireless charging system from relying on universal but potentially unsuitable fixed thresholds, allowing for more accurate determination of foreign object presence and significantly improving the accuracy and sensitivity of foreign object detection. Second, this adaptive calibration strategy effectively solves the problem of false FOD (Foreign Object Defect) reports caused by the inherent differences in the characteristics of wireless charging devices in the market. By performing real-time or pre-calibration on the current device, the wireless charging system can establish a matching "normal" power loss baseline, avoiding false alarms even in the absence of foreign objects and significantly reducing the false alarm rate. Furthermore, accurate foreign object detection and reduced false alarms not only improve the safety of the wireless charging system and avoid potential risks caused by foreign objects, but also provide users with a smoother and more reliable charging experience, eliminating the inconvenience and complaints caused by frequent charging interruptions, thereby enhancing the product's market competitiveness and user satisfaction.

[0026] The further objectives and advantages of this application will become fully apparent from the following description and accompanying drawings. Attached Figure Description

[0027] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0028] Figure 1 The illustration shows a flowchart of a foreign object detection parameter calibration method for wireless charging according to an embodiment of this application.

[0029] Figure 2 Another flowchart of a foreign object detection parameter calibration method for wireless charging according to an embodiment of this application is illustrated.

[0030] Figure 3 The illustration shows a flowchart of an example of a foreign object detection parameter calibration method for wireless charging according to an embodiment of this application.

[0031] Figure 4 The figure shows a structural block diagram of a foreign object detection parameter calibration system for wireless charging according to an embodiment of this application.

[0032] Figure 5 The figure shows another structural block diagram of a foreign object detection parameter calibration system for wireless charging according to an embodiment of this application. Detailed Implementation

[0033] Exemplary embodiments according to this application will now be described in detail with reference to the accompanying drawings. It is obvious that the described exemplary embodiments are merely a part of the embodiments of this application, and not all of the embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein.

[0034] It is understood that the term "a" should be understood as "at least one" or "one or more," meaning that in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. The term "a" should not be construed as a limitation on the quantity. "Multiple" means two or more.

[0035] While ordinal numbers such as “first,” “second,” etc., will be used to describe various components, there is no limitation on which components are used herein. The term is used only to distinguish one component from another. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component, without departing from the teachings of this application. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0036] The terminology used herein is for the purpose of describing various embodiments only and is not intended to be limiting. The singular form used herein is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it will be understood that the terms “comprising” and / or “having”, as used in this specification, specify the presence of the described features, numbers, operations, components, elements, or combinations thereof, without excluding the presence or addition of one or more other features, numbers, operations, components, elements, or combinations thereof.

[0037] In view of the technical deficiencies disclosed in the background art, this application proposes a method for calibrating foreign object detection parameters for wireless charging. Figure 1 This is a flowchart of a foreign object detection parameter calibration method for wireless charging according to an embodiment of this application. Figure 1 As shown, the foreign object detection parameter calibration method for wireless charging according to an embodiment of this application includes the following steps: S110, confirming that the transmitting coil of the charger and the receiving coil of the device to be charged are adjusted to a preset relative position; S120, adjusting the transmitting power of the transmitting coil at the preset relative position; S130, calculating the power loss value to obtain the power loss value under different transmitting power conditions calibrated at the preset relative position, wherein the power loss value is used as a foreign object detection parameter.

[0038] In step S110, it is confirmed that the transmitter coil of the charger and the receiver coil of the device to be charged have been adjusted to a preset relative position. A relative position refers to the position of one location relative to another. It is determined that the transmitter coil of the charger and the receiver coil of the device to be charged have been adjusted to the preset relative position as long as the relative relationship between the positions of the transmitter coil and the device to be charged meets a preset condition.

[0039] For example, a preset condition for the relative position of the transmitting coil and the device to be charged is that the device to be charged is located at a specific orientation (e.g., directly above) of the transmitting coil and at a specific distance (e.g., less than 1.5cm). When the device to be charged is located at a specific distance (e.g., less than 1.5cm) of the specific orientation (e.g., directly above) of the transmitting coil, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the preset relative position.

[0040] For example, a preset condition for the relative position of the transmitting coil and the device to be charged is: the transmitting coil reaches the first preset transmitting position and the receiving coil reaches the first preset receiving position; when the transmitting coil reaches the first preset transmitting position and the receiving coil reaches the first preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the first preset relative position.

[0041] For example, another preset condition for the relative relationship between the position of the transmitting coil and the position of the device to be charged is: the position of the transmitting coil reaches the second preset transmitting position, and the position of the receiving coil reaches the first preset receiving position; when the position of the transmitting coil reaches the second preset transmitting position and the position of the receiving coil reaches the first preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the second preset relative position.

[0042] For example, another preset condition for the relative position of the transmitting coil and the device to be charged is: the transmitting coil reaches the third preset transmitting position and the receiving coil reaches the first preset receiving position; when the transmitting coil reaches the third preset transmitting position and the receiving coil reaches the first preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the third preset relative position.

[0043] For example, a preset condition for the relative position of the transmitting coil and the device to be charged is: the transmitting coil reaches the first preset transmitting position and the receiving coil reaches the second preset receiving position; when the transmitting coil reaches the first preset transmitting position and the receiving coil reaches the second preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the fourth preset relative position.

[0044] For example, a preset condition for the relative position of the transmitting coil and the device to be charged is: the transmitting coil reaches the first preset transmitting position and the receiving coil reaches the third preset receiving position; when the transmitting coil reaches the first preset transmitting position and the receiving coil reaches the third preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the fifth preset relative position.

[0045] For example, a preset condition for the relative position of the transmitting coil and the device to be charged is: the transmitting coil reaches the second preset transmitting position and the receiving coil reaches the second preset receiving position; when the transmitting coil reaches the second preset transmitting position and the receiving coil reaches the second preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the sixth preset relative position.

[0046] For example, a preset condition for the relative position of the transmitting coil and the device to be charged is: the transmitting coil reaches the third preset transmitting position and the receiving coil reaches the third preset receiving position; when the transmitting coil reaches the third preset transmitting position and the receiving coil reaches the third preset receiving position, it is determined that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the seventh preset relative position.

[0047] Before calibrating foreign object detection (FOD) parameters, it is essential to ensure optimal energy transfer efficiency between the charger's transmitting coil and the receiving coil of the device being charged. Only with good coupling can the power loss value caused purely by the characteristics of the charger and the device being charged, rather than by poor coupling, be accurately calculated, thus establishing a stable and reliable FOD benchmark. This minimizes data noise caused by positional deviations, ensuring that the subsequently calibrated power loss value accurately reflects the inherent characteristics of the device being charged and avoids false FOD reports.

[0048] Furthermore, the positions of the receiving coils in electronic devices on the market vary. For example, most receiving coils are centered, while some devices, to avoid cameras, have their receiving coils positioned lower. Therefore, during use, the transmitting coil (TX) and receiving coil (RX) cannot be well coupled, resulting in poor overall wireless system charging efficiency, significant heat generation in both coils, and a correspondingly longer charging time. This application aims to determine the optimal coupling positions for the charger with different models of electronic devices. When different electronic devices are placed on the charger, the positions of the charger's transmitting coil and / or the electronic device are adjusted to ensure better coupling between the charger's transmitting coil and the electronic device's receiving coil.

[0049] It is understandable that before calibrating the foreign object detection parameters, the relative position between the charger's transmitting coil and the receiving coil of the device being charged can be adjusted to a commonly used or default relative position. For example, users are accustomed to placing their phones in the first position, so that the relative position between the charger's transmitting coil and the device's receiving coil is often in the first relative position. This ensures that the subsequently measured foreign object detection parameters are based on the user's usage habits, thus avoiding false FOD (Foreign Object Detection) reports to some extent.

[0050] It should also be understood that the transmitting coil and the receiving coil can be coupled by adjusting only the position of the transmitting coil, or only the position of the receiving coil, or by adjusting both the positions of the transmitting coil and the receiving coil.

[0051] Furthermore, at least one preset transmission position can be configured for the transmitting coil and / or a preset receiving position can be configured for the receiving coil. When it is confirmed that the transmitting coil of the charger is adjusted to the preset transmission position and / or the receiving coil of the device to be charged is adjusted to the preset receiving position, the foreign object detection parameter calibration can be performed.

[0052] Accordingly, in step S110, if it is confirmed that the transmitting coil of the charger is adjusted to a preset transmitting position and / or the receiving coil of the device to be charged is adjusted to a preset receiving position, then it is confirmed that the transmitting coil of the charger and the receiving coil of the device to be charged are adjusted to a preset relative position.

[0053] In some embodiments, the transmitting coil in the charger is movable, and the relative position of the charger's transmitting coil and the receiving coil of the device to be charged can be adjusted by adjusting the charger's transmitting coil. In one embodiment of this application, the charger is dedicated to charging a specific electronic device, requiring only one preset relative position to be determined. In other embodiments of this application, the charger charges multiple different electronic devices, requiring two or more preset relative positions to be determined.

[0054] Specifically, in one example of this application, the preset transmission position is set through self-learning. In one embodiment of this application, the position of the charger's transmitting coil is first adjusted. This typically means that the charger's transmitting coil will move within a preset range, for example, driven by a motor. After each position adjustment of the transmitting coil, the energy intensity received by the test receiving coil at each position is further determined. The energy intensity received by the receiving coil is typically represented by the receiving power of the receiving coil. The value of the energy intensity received by the test receiving coil can be fed back to the charger through communication between the test device to be charged and the charger. By monitoring and recording the received energy intensity at different positions, the change in coupling efficiency between the transmitting and receiving coils can be accurately grasped. After traversing all preset positions and obtaining the corresponding energy intensity data, the position of the transmitting coil when the energy intensity received by the receiving coil is the maximum is taken as the preset transmission position. This position represents the state where the geometric relationship between the transmitting and receiving coils is optimized and the energy transmission efficiency is the highest.

[0055] Accordingly, in one embodiment of this application, obtaining the preset transmission position through a self-learning mode includes: adjusting the position of the transmitter coil of the charger, and determining the energy intensity received by the receiving coil for testing when the transmitter coil is in each position; and taking the position of the transmitter coil when the energy intensity received by the receiving coil is the maximum as the preset transmission position.

[0056] Furthermore, the determination of preset relative positions is not limited to self-learning mode; it can also comprehensively consider the characteristics of various practical application scenarios. For example, it can be matched based on the customer's charging habits, that is, learning and recording the user's usual phone placement positions as preset relative positions. Simultaneously, the characteristics of the device being charged can also be considered; for example, the position of the receiving coil inside the phone may not be in the center of the back of the phone, and this off-center coil design will affect the optimal coupling point. Moreover, the structural characteristics of the charging environment, such as the internal space of an in-vehicle wireless charger or the tilt angle of the interior, may also determine a specific optimal coupling position. By comprehensively considering these factors, one or more preset optimal coupling position lists can be generated for subsequent foreign object detection parameter calibration processes.

[0057] Specifically, the most common way to adjust the charger's transmitting coil to the preset transmitting position is by using a precise positioning or driving mechanism, such as a motor that drives the transmitting coil to the preset transmitting position.

[0058] More specifically, after the preset transmission position is determined, a control drive component (e.g., a stepper motor, DC servo motor, or linear actuator) drives the charger's transmitter coil to move. Upon receiving a drive command, the motor or other drive component moves or guides the charger's transmitter coil from its current position to its final, determined preset transmission position. For wireless chargers employing a movable coil design, this step achieves physical displacement of the transmitter coil to optimize coupling.

[0059] For example, in a car wireless charger, if a self-learning mode determines that the phone charges most efficiently at a specific tilt angle and horizontal position, then before formal parameter calibration, the charger's internal motor will drive the module carrying its transmitting coil to move to that preset tilt angle and horizontal position. This might be because factors such as the tilt angle of the vehicle's interior or the phone's receiving coil not being centered on its back panel mean the optimal coupling position isn't simply at the exact center. This precise adjustment ensures that the power loss values ​​calculated under different transmission power conditions accurately reflect the inherent characteristics of the device being charged under ideal coupling conditions, thus providing accurate calibration parameters for foreign object detection.

[0060] In step S110, the position of the driving component can be measured to determine whether the transmitting coil has reached the preset transmitting position, thereby confirming that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the preset relative position.

[0061] In some embodiments, the transmitting coil in the charger is fixed, and the relative positions of the charger's transmitting coil and the receiving coil of the device to be charged can be adjusted by moving the device to be charged. For example, the charger has one or more location markers indicating the placement position of the device to be charged; the relative positions of the receiving coil of the device to be charged and the transmitting coil in the charger differ depending on where the device to be charged is placed.

[0062] In step S110, when the relative positions of the receiving coil of the device to be charged and the charger are different, the energy intensity received by the receiving coil is different. It can be determined by measuring the energy intensity received by the receiving coil or by other means whether the receiving coil of the device to be charged has been adjusted to the preset receiving position, thereby confirming that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the preset relative position.

[0063] In other embodiments, the transmitting coil in the charger is movable, and the relative positions of the transmitting coil of the charger and the receiving coil of the device to be charged can be adjusted by moving the transmitting coil and moving the device to be charged.

[0064] In step S110, the position of the driving component can be measured to determine whether the transmitting coil has reached the preset transmitting position, and the energy intensity received by the receiving coil or other means can be measured to determine whether the receiving coil of the device to be charged has been adjusted to the preset receiving position, thereby confirming that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to the preset relative position.

[0065] In step S120, the transmission power of the transmitting coil is adjusted at the preset relative position. By calibrating at multiple transmission power points, a comprehensive understanding and recording of the power loss behavior pattern in the absence of foreign objects can be achieved, particularly its relationship with the transmission power.

[0066] In one embodiment of this application, step S120 includes: gradually increasing the transmission power of the transmitting coil at the preset relative position (e.g., ...). Figures 1 to 3 (As shown). This means that the charger's transmitting coil (TX) will not operate at a single power level, but will gradually increase its transmitting energy output according to a predetermined strategy, starting from a lower initial power value. This gradual increase typically involves a series of discrete power points, rather than continuous stepless adjustment. For example, multiple power levels such as 5W, 7.5W, 10W, 12.5W, and even 15W can be preset for testing. At each specific transmitting power level, a stable transmission will be maintained for a period of time to allow for accurate measurement of the received power of the device being charged.

[0067] In step S130, a power loss value is calculated to obtain the power loss value under different transmission power conditions calibrated at the preset relative position, wherein the power loss value serves as a foreign object detection parameter. The power loss value refers to the power loss of the receiving coil of the device to be charged relative to the transmission power. Under optimal coupling conditions and without foreign object interference, the inherent energy loss at different transmission power levels is quantified and recorded. This energy loss is used as the power loss value of the normal operating baseline to establish a unique feature model for the current device to be charged. This allows for accurate differentiation between abnormal power drops caused by metallic foreign objects and normal power fluctuations when no foreign objects are present during subsequent actual charging, significantly improving the accuracy and sensitivity of foreign object detection and effectively reducing the false alarm rate.

[0068] Specifically, the power loss value can be calculated using the following formula: Power loss value = Transmit power - Received power of the receiving coil. This calculation process is repeated at each adjusted transmit power level, thereby obtaining a series of specific power loss values ​​at the preset relative positions under different transmit power conditions. These power loss values ​​collectively constitute the power loss characteristics set of the device to be charged under ideal conditions, providing accurate calibration data for subsequent foreign object detection and judgment.

[0069] For example, in a car wireless charging scenario, after the charger's transmitting coil and the receiving coil with the charging device are precisely adjusted to a preset relative position, a series of power transmissions and data acquisitions are performed. If the transmitting power is 5W and the received power of the phone's receiving coil is measured to be 4W, then the power loss is 1W = (5W - 4W). Subsequently, the transmitting power is increased to 10W, and the received power is measured to be 8W, at which point the power loss is 2W = (10W - 8W). Next, the transmitting power is increased again to 15W, and the received power is measured to be 12W, at which point the power loss is 3W = (15W - 12W). By calculating a series of power loss values ​​of 1W, 2W, 3W, etc., at different transmitting power points, a precise calibration curve is established for the detection of foreign objects in the ideal charging state of this phone. Subsequently, during actual charging, if the power loss at a specific transmitting power is significantly higher than this calibration value, the presence of a foreign object can be more accurately determined.

[0070] It is worth mentioning that by calculating and obtaining the power loss values ​​under different transmission power conditions at the same preset relative position, multiple discrete transmission power-power loss value data points can be obtained. The power loss values ​​calibrated at different transmission powers at the same preset relative position can be fitted to obtain the transmission power-power loss value calibration curve corresponding to the optimal coupling position. Through fitting, discrete data points can be transformed into a continuous curve or a mathematical function model. On the one hand, actual measurement data often contains certain noise and measurement errors. The fitting process can effectively smooth these data, remove or reduce the influence of noise, thereby revealing a more realistic trend and pattern behind the data. On the other hand, in actual use, the transmission power of the charger may not be strictly limited to a few preset points, but can continuously vary within a certain range or take any value. By using the fitted curve or function, the theoretical power loss value under the condition of no foreign objects can be accurately predicted based on any transmission power monitored in real time. This provides a high-precision, continuous reference benchmark for subsequent accurate foreign object detection, which can improve the sensitivity and accuracy of detection to a certain extent, avoiding false alarms or missed alarms that may be caused by relying solely on a limited number of discrete points for judgment.

[0071] Specifically, the power loss values ​​calculated for all different transmit powers at the same preset relative position are collected. These data points can be viewed as a series of transmit power-power loss pairs. For example, if the power loss is measured as 1W at a 5W transmit power, 2W at a 10W transmit power, and 3W at a 15W transmit power, then the data point set {(5W, 1W), (10W, 2W), (15W, 3W)} will be obtained. Subsequently, mathematical or statistical methods are used to fit these discrete data points. Common fitting methods include, but are not limited to, linear regression analysis or multinomial regression analysis.

[0072] In linear regression analysis, if the observed power loss value and the transmission power show an approximately linear relationship, a linear regression algorithm can be used to find the best-fitting straight line and minimize the sum of squared vertical distances between the actual data points and the fitted straight line.

[0073] In polynomial regression analysis, if the data points exhibit a non-linear trend, polynomial fitting can be chosen. The coefficients in the polynomial are determined to make the fitted curve as close as possible to all data points.

[0074] Regardless of the fitting algorithm used, the core objective is to find the continuous functional relationship that best represents the overall trend of these discrete data points. This process is typically accomplished by a dedicated data processing module or an embedded computing unit.

[0075] For example, continuing with the previous example, when the system acquires three sets of measurement data at a specific preset relative position: (5W, 1W), (10W, 2W), and (15W, 3W), this clearly shows an approximately linear relationship. At this point, a linear regression algorithm is used to fit these three sets of data. Through calculation, a fitted straight line with the expression Ploss = 0.2Ptx can be obtained, where Ploss represents the power loss value and Ptx represents the transmission power. This straight line is the transmission power-power loss calibration curve corresponding to the optimal coupling position. When the transmission power during actual charging is 7.5W, its predicted normal power loss value should be 0.2 * 7.5W = 1.5W. If the power loss is found to be much greater than 1.5W in actual measurement, it can serve as an important basis for judging the presence of foreign objects.

[0076] Accordingly, Figure 2 Another flowchart of a foreign object detection parameter calibration method for wireless charging according to an embodiment of this application is illustrated. Figure 2 As shown, the foreign object detection parameter calibration method for wireless charging further includes step S140, which fits the power loss value calibrated at different transmission powers at the same preset relative position to obtain the transmission power-power loss value calibration curve corresponding to the preset relative position.

[0077] Steps S110 to S130 or S110 to S140 describe the process of calibrating the power loss value under different transmission power conditions at the same preset relative position. When there are multiple preset relative positions, the transmitter coil of the charger is adjusted to another preset relative position, and steps S120 and S130 or steps S120 to S140 are repeated.

[0078] Accordingly, in one embodiment of this application, the foreign object detection parameter calibration method for wireless charging further includes: confirming that the transmitting coil of the charger and the receiving coil of the device to be charged are adjusted to another preset relative position; adjusting the transmitting power of the transmitting coil at the other preset relative position; and calculating the power loss value to obtain the power loss value under different transmitting power conditions calibrated at the other preset relative position.

[0079] Based on the above-mentioned method for calibrating foreign object detection parameters for wireless charging, this application proposes a foreign object detection parameter calibration system for wireless charging. Figure 4 The figure shows a structural block diagram of a foreign object detection parameter calibration system for wireless charging according to an embodiment of this application.

[0080] like Figure 4As shown, the foreign object detection parameter calibration system for wireless charging includes a position confirmation unit 10, a transmission power control unit 20, and a power loss value calculation unit 30. The position confirmation unit 10 confirms that the transmitter coil of the charger and the receiver coil of the device to be charged are adjusted to a preset relative position; the transmission power control unit 20 adjusts the transmission power of the transmitter coil at the preset relative position; and the power loss value calculation unit 30 calculates the power loss value to obtain the power loss value under different transmission power conditions calibrated at the preset relative position, wherein the power loss value serves as a foreign object detection parameter.

[0081] In one embodiment of this application, the transmit power control unit 20 is further configured to gradually increase the transmit power of the transmit coil at the preset relative position.

[0082] In one embodiment of this application, such as Figure 5 As shown, the foreign object detection parameter calibration system for wireless charging further includes a fitting unit 40. The fitting unit 40 is used to fit the power loss value calibrated at different transmission powers at the same preset relative position to obtain the transmission power-power loss value calibration curve corresponding to the preset relative position.

[0083] Those skilled in the art will understand that the specific functions and operations of each module in the aforementioned foreign object detection parameter calibration system for wireless charging have been referenced above. Figure 1 and Figure 2 The method for calibrating foreign object detection parameters for wireless charging is described in detail here, and therefore, its repeated description will be omitted.

[0084] The foreign object detection parameter calibration system for wireless charging according to the embodiments of this application can be implemented in various wireless chargers.

[0085] In summary, the method and system for calibrating foreign object detection parameters for wireless charging have been clarified. The method for calibrating foreign object detection parameters for wireless charging can obtain accurate power loss values ​​for a specific device under different power conditions as foreign object detection parameters, thereby more accurately determining the presence of foreign objects and greatly improving the accuracy and sensitivity of foreign object detection.

[0086] The present application and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present application. The actual structure is not limited to this. In conclusion, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of the present application, such design should fall within the protection scope of the present application.

Claims

1. A method for calibrating foreign object detection parameters for wireless charging, characterized in that, include: Confirm that the charger's transmitting coil and the device's receiving coil are adjusted to the preset relative positions; Adjust the transmission power of the transmitting coil at the preset relative position; Calculate the power loss value to obtain the power loss value under different transmission power conditions calibrated at the preset relative position, wherein the power loss value is used as a foreign object detection parameter.

2. The method for calibrating foreign object detection parameters for wireless charging according to claim 1, characterized in that, Adjusting the transmission power of the transmitting coil at the preset relative position includes: gradually increasing the transmission power of the transmitting coil at the preset relative position.

3. The method for calibrating foreign object detection parameters for wireless charging according to claim 1, characterized in that, The method for calibrating foreign object detection parameters for wireless charging further includes: fitting the power loss values ​​calibrated at different transmission powers at the same preset relative position to obtain the transmission power-power loss value calibration curve corresponding to the preset relative position.

4. The method for calibrating foreign object detection parameters for wireless charging according to claim 1, characterized in that, The foreign object detection parameter calibration method for wireless charging also includes: Confirm that the charger's transmitting coil and the device's receiving coil have been adjusted to another preset relative position; Adjust the transmission power of the transmitting coil at another preset relative position; Calculate the power loss value to obtain the power loss value under different transmission power conditions calibrated at another preset relative position.

5. The method for calibrating foreign object detection parameters for wireless charging according to claim 1, characterized in that, Confirming that the transmitter coil of the charger and the receiver coil of the device to be charged are adjusted to preset relative positions includes: confirming that the transmitter coil of the charger is adjusted to a preset transmitter position and / or the receiver coil of the device to be charged is adjusted to a preset receiver position.

6. The method for calibrating foreign object detection parameters for wireless charging according to claim 5, characterized in that, The preset launch position is obtained through a self-learning mode.

7. The method for calibrating foreign object detection parameters in wireless charging according to claim 6, characterized in that, Obtaining the preset launch position through self-learning mode includes: Adjust the position of the charger's transmitting coil and determine the energy intensity received by the test receiving coil when the transmitting coil is in each position; The position of the transmitting coil when the energy intensity received by the receiving coil is the maximum is taken as the preset transmitting position.

8. A foreign object detection parameter calibration system for wireless charging, characterized in that, include: The position confirmation unit is used to confirm that the transmitting coil of the charger and the receiving coil of the device to be charged have been adjusted to a preset relative position; A transmission power control unit is used to adjust the transmission power of the transmission coil at the preset relative position; A power loss value calculation unit is used to calculate the power loss value to obtain the power loss value under different transmission power conditions calibrated at the preset relative position, wherein the power loss value is used as a foreign object detection parameter.

9. The foreign object detection parameter calibration system for wireless charging according to claim 8, characterized in that, The transmit power control unit is further configured to gradually increase the transmit power of the transmit coil at the preset relative position.

10. The foreign object detection parameter calibration system for wireless charging according to claim 8, characterized in that, Also includes: The fitting unit is used to fit the power loss value calibrated at different transmission powers at the same preset relative position to obtain the transmission power-power loss value calibration curve corresponding to the preset relative position.

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