A foreign object detection method, system and electronic device for wireless charging

Abstract

The present invention provides a foreign body detection method, system and electronic device for wireless charging, which relates to the field of wireless charging technology. The method includes: connecting the transmitting end to a power supply, inputting a preset current to the unloaded transmitting end, and detecting the real-time current signal in the transmitting end; comparing the real-time current signal with the standard current signal to determine whether the real-time current signal is normal; when the real-time current signal is abnormal, preliminarily determining that there may be a conductive foreign body near the transmitting end, controlling the transmitting end to send a preset number of detection signals to the outside, and detecting the real-time voltage wave at both ends of the transmitting component of the transmitting end; according to the real-time voltage wave and the preset threshold, obtaining the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold; when the real-time number is less than the preset number, determining that there is a conductive foreign body within the radiation range of the transmitting end. During the detection process, there is no need to add external equipment to the wireless charging device, and the complexity and cost of the wireless charging system are not increased.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless charging, and in particular to a foreign object detection method, system and electronic equipment for wireless charging. Background Art

[0002] During the wireless charging process, if there is a conductive foreign object such as metal between the transmitter and the receiver, an induced current will be generated inside the metal foreign object. Due to the resistance characteristics of the metal conductor, the induced current will cause the foreign object to heat up, and may even reach a temperature high enough to burn the surface of the human body. In severe cases, it may cause safety accidents such as fire. In order to ensure the safety and stability of the wireless charging process, conductive foreign object detection technology is particularly important.

[0003] Existing methods for detecting foreign matter in conductors include machine vision detection, frequency-modulated wave radar detection, and infrared temperature detection, which require the use of camera equipment, radar equipment, or temperature monitoring equipment. These methods require the addition of additional equipment on the basis of the wireless charging system, which will increase the complexity and cost of the system. Summary of the invention

[0004] The problem to be solved by the present invention is that the existing conductor foreign body detection method needs to add additional equipment on the basis of the wireless charging system, which increases the complexity and cost of the system.

[0005] To solve the above problems, in a first aspect, the present invention provides a foreign object detection method for wireless charging, comprising:

[0006] Input a preset current to the unloaded transmitter and detect a real-time current signal in the transmitter;

[0007] Comparing the real-time current signal with a standard current signal to determine whether the real-time current signal is normal, wherein the standard current signal is a current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end;

[0008] When the real-time current signal is abnormal, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage wave at both ends of the transmitting component of the transmitting end is detected, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil;

[0009] According to the real-time voltage wave and the preset threshold, obtaining the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold;

[0010] When the real-time number is less than the preset number, it is determined that there is a conductive foreign object within the radiation range of the transmitting end.

[0011] Optionally, comparing the real-time current signal with a standard current signal to determine whether the real-time current signal is normal includes:

[0012] According to the real-time current signal, a real-time current amplitude and a real-time duty cycle are obtained;

[0013] According to the standard current signal, a standard current amplitude and a standard duty cycle are obtained;

[0014] When the real-time current amplitude is greater than the standard current amplitude and the real-time duty cycle is less than the standard duty cycle, it is determined that the real-time current signal is abnormal.

[0015] Optionally, when the real-time current signal is abnormal, after controlling the transmitting end to send a preset number of detection signals to the outside, detecting the real-time voltage wave at both ends of the transmitting component of the transmitting end comprises:

[0016] When the real-time current signal is abnormal, controlling the transmitting end to periodically send the detection signal to the outside, and determining whether a feedback signal from the receiving end is received;

[0017] When receiving the feedback signal, determining that the foreign object within the radiation range of the transmitting end is a normal receiving end;

[0018] When the feedback signal is not received, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage waves at both ends of the transmitting component of the transmitting end are detected.

[0019] Optionally, obtaining, based on the real-time voltage wave and a preset threshold, the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold comprises:

[0020] Inputting the real-time voltage wave to the positive input terminal of the comparator to obtain a real-time comparison waveform output by the comparator, wherein the input value of the negative input terminal of the comparator is a preset threshold value;

[0021] The real-time comparison waveform is analyzed to obtain the number of high levels of the real-time comparison waveform, which is recorded as the real-time number.

[0022] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0023] Starting from the starting end of the real-time voltage wave, picking up the peak value of the real-time voltage wave within a preset time length to obtain a real-time peak total value;

[0024] Starting from the starting end of the standard voltage wave, the peak value of the wave within the preset time length in the standard voltage wave is picked up to obtain the total standard peak value, wherein the standard voltage wave is the voltage wave at both ends of the transmitting component after the transmitting end sends a preset number of detection signals to the outside when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end;

[0025] A first interference ratio is obtained according to the real-time peak total value and the standard peak total value, wherein the first interference ratio is used to predict the volume of the conductive foreign matter.

[0026] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0027] Analyze the duration of the high level in the real-time comparison waveform to obtain the actual duration;

[0028] Inputting the standard voltage wave into the positive input terminal of the comparator to obtain the standard comparison waveform;

[0029] Compare the duration of the high level in the waveform according to the standard to obtain the standard duration;

[0030] A second interference ratio is obtained according to the actual duration and the standard duration, wherein the second interference ratio is used to predict the volume of the conductive foreign matter.

[0031] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0032] According to the real-time comparison waveform and the standard comparison waveform, a first duty cycle of the real-time comparison waveform and a second duty cycle of the standard comparison waveform are correspondingly obtained;

[0033] A third interference ratio is obtained according to the first duty cycle and the second duty cycle, wherein the third interference ratio is used to predict the volume of the conductive foreign matter.

[0034] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0035] Obtaining an influence degree value according to the first interference ratio, the second interference ratio, the third interference ratio, and a preset weight corresponding to each interference ratio;

[0036] The volume and danger level of the conductive foreign matter are predicted according to the impact level value.

[0037] In a second aspect, the present invention further provides a wireless charging foreign object detection system, comprising:

[0038] A current detection module, used to input a preset current to the unloaded transmitter and detect a real-time current signal in the transmitter;

[0039] A judgment module, used for comparing the real-time current signal with a standard current signal to judge whether the real-time current signal is normal, wherein the standard current signal is a current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end;

[0040] A voltage wave detection module, used for controlling the transmitting end to send a preset number of detection signals to the outside when the real-time current signal is abnormal, and then detecting the real-time voltage wave at both ends of the transmitting component of the transmitting end, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil;

[0041] A voltage wave analysis module, used to obtain the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold value according to the real-time voltage wave and the preset threshold value;

[0042] The foreign object confirmation module is used to determine that there is a conductive foreign object within the radiation range of the transmitting end when the real-time number is less than a preset number.

[0043] In a third aspect, the present invention provides an electronic device, including a memory and a processor;

[0044] The memory is used to store computer programs;

[0045] The processor is used to implement the foreign object detection method for wireless charging as described in the first aspect when executing the computer program.

[0046] The beneficial effects of the wireless charging foreign object detection method, system and electronic device of the present invention are:

[0047] Connect the transmitting end to a power source, input a preset current to the unloaded transmitting end, and detect a real-time current signal in the transmitting end; compare the real-time current signal with a standard current signal to determine whether the real-time current signal is normal, the standard current signal being the current signal in the transmitting end after the preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end; when the real-time current signal is abnormal, preliminarily determine that there may be conductive foreign matter near the transmitting end, control the transmitting end to send a preset number of detection signals to the outside, and then detect the real-time voltage wave at both ends of the transmitting component of the transmitting end, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil; according to the real-time voltage wave and a preset threshold, obtain the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold; when the real-time number is less than the preset number, it is further determined that there is a conductive foreign matter within the radiation range of the transmitting end. During the detection process, there is no need to add external equipment to the wireless charging device. First, a preliminary judgment is made using the real-time current signal normally generated in the transmitter, and then a further judgment is made using the real-time voltage wave generated by the transmitting coil and capacitor in the transmitter, without increasing the complexity and cost of the wireless charging system. After two judgments, it is determined whether there are conductive foreign objects near the transmitter. In the absence of a detection coil or a receiving end load, the detection of conductive foreign objects can be completed independently. The detection dependence is small, and real-time monitoring is more convenient, which is conducive to regular inspection and protection of the transmitter. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A schematic diagram of a flow chart of a foreign object detection method for wireless charging provided by an embodiment of the present invention;

[0049] Figure 2 A partial structural schematic diagram of a wireless charging system provided by an embodiment of the present invention;

[0050] Figure 3 A waveform diagram of a standard current signal provided by an embodiment of the present invention;

[0051] Figure 4 A waveform diagram of a real-time current signal provided by an embodiment of the present invention;

[0052] Figure 5 A schematic diagram of a real-time comparison waveform provided by an embodiment of the present invention;

[0053] Figure 6 A schematic diagram of a standard comparison waveform provided by an embodiment of the present invention;

[0054] Figure 7 A schematic diagram of the structure of a wireless charging foreign object detection system provided by an embodiment of the present invention;

[0055] Figure 8A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0056] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be interpreted as being limited to the embodiments described herein. On the contrary, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0057] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0058] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to"; the term "based on" means "based at least in part on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc. mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0059] It should be noted that the modifications of "one" and "plurality" mentioned in the present invention are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0060] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are only used for illustrative purposes, and are not used to limit the scope of these messages or information.

[0061] In view of the problems existing in the above-mentioned related technologies, this embodiment provides a foreign object detection method, system and electronic device for wireless charging.

[0062] like Figure 1 As shown, an embodiment of the present invention provides a wireless charging foreign object detection method, comprising:

[0063] S1: Input a preset current to the unloaded transmitter and detect the real-time current signal in the transmitter.

[0064] Specifically, the preset current can be selected from any current value within the current range that the transmitter can withstand. Figure 2 As shown in the figure, after the transmitter is connected to the power supply, the current will be induced at the receiving end. The receiving end is connected to the energy storage battery, and the induced current charges the energy storage battery. After the transmitter is connected to the power supply, the current is generated in the transmitter. You can use a current sensor or current detection instrument to connect to Figure 2 At the detection points 1 and 2 in the figure, the real-time current signal of the transmitter is obtained. Figure 2 As shown, when the receiving end does not exist, that is, there is no receiving end at the position corresponding to the transmitting end, it indicates that the transmitting end is unloaded, that is, after the preset current is passed through the transmitting end, no current will be induced in any receiving end.

[0065] S2: Compare the real-time current signal with the standard current signal to determine whether the real-time current signal is normal, wherein the standard current signal is the current signal in the transmitter after a preset current is input to the transmitter when the transmitter is unloaded and there is no conductive foreign matter within the radiation range of the transmitter.

[0066] S3: When the real-time current signal is abnormal, the transmitter is controlled to send a preset number of detection signals to the outside, and then the real-time voltage wave at both ends of the transmitter component of the transmitter is detected, wherein the transmitter component includes a transmitter coil and a capacitor connected in series with the transmitter coil. When the real-time current signal is normal, the subsequent detection is stopped, and the detection is started again after the next detection cycle.

[0067] Specifically, the transmitting end can be controlled to continuously generate 8 detection signals to the outside, and one detection signal is a sine-like alternating current waveform signal, such as Figure 2 The transmitting component is a transmitting coil L and a capacitor C, which are connected in series. The real-time voltage across the transmitting component (i.e. Figure 2 The real-time voltage between detection point 3 and detection point 4 in the waveform is obtained by calculating the real-time voltage wave.

[0068] S4: According to the real-time voltage wave and the preset threshold, obtain the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold.

[0069] Specifically, after the transmitting end continuously transmits multiple detection signals, a certain amount of electrical energy is stored in the transmitting coil and the capacitor. When the detection signal stops being sent, the energy stored in the capacitor will flow out to charge the transmitting coil. When the electrical energy in the capacitor is released, the energy in the charged transmitting coil is released and charges the capacitor again. This cycle repeats until the energy is gradually exhausted. Therefore, the real-time voltage wave is a waveform that fluctuates up and down and gradually weakens. Based on the preset threshold, it is analyzed whether each peak of the real-time voltage wave exceeds the preset threshold, and finally the number of peaks exceeding the preset threshold is obtained, that is, the real-time number of times.

[0070] S5: When the real-time number is less than the preset number, it is determined that there is a conductive foreign object within the radiation range of the transmitter. When the real-time number is equal to the preset number, it is determined that there is no conductive foreign object within the radiation range of the transmitter. Generally, the real-time number will not be greater than the preset number. If it does, it may be temporarily affected by the surrounding environment. This situation is not considered and is classified as a normal phenomenon.

[0071] Specifically, when there is a conductor foreign body near the transmitting end, a magnetic field is generated around the transmitting end, and the conductor foreign body absorbs the energy of the magnetic field and generates heat. The energy absorbed by the conductor foreign body comes from the energy stored in the transmitting component. Therefore, the energy stored in the transmitting component of the transmitting end is reduced, resulting in the weakening of the real-time voltage wave at both ends of the transmitting component. The standard number is the number of times that the voltage wave at both ends of the transmitting component exceeds the preset threshold after the transmitting end sends a preset number of detection signals to the outside when the transmitting end is unloaded and there is no conductor foreign body within the radiation range of the transmitting end. The preset number can be slightly adjusted on the basis of the standard number. For example, in order to increase the accuracy of detection and avoid false alarms, if the standard number is 5 times, the preset number can be set to 4 times, that is, when the real-time number is 4 times, no alarm can be issued or the transmitting end can be stopped, because at this time it may be the influence of the surrounding environment, causing the fluctuation of the real-time voltage wave. Of course, the preset number is preferably set to a value equal to the standard number, so that the detection is more comprehensive at this time and no false alarms will be caused.

[0072] In this embodiment, the transmitting end is connected to a power supply, a preset current is input to the unloaded transmitting end, and a real-time current signal in the transmitting end is detected; the real-time current signal is compared with a standard current signal to determine whether the real-time current signal is normal, the standard current signal being the current signal in the transmitting end after the preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end; when the real-time current signal is abnormal, it is preliminarily determined that there may be a conductive foreign matter near the transmitting end, and after the transmitting end is controlled to send a preset number of detection signals to the outside, the real-time voltage wave at both ends of the transmitting component of the transmitting end is detected, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil; since when there is a conductive foreign matter near the transmitting end, part of the energy emitted by the transmitting end will be absorbed by the conductive foreign matter, and the generated real-time voltage wave will be different from the voltage wave generated when there is no conductive foreign matter, therefore, according to the real-time voltage wave and the preset threshold, the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold is obtained; when the real-time number is less than the preset number, it is further determined that there is a conductive foreign matter within the radiation range of the transmitting end. During the detection process, there is no need to add external equipment to the wireless charging device. First, a preliminary judgment is made using the real-time current signal normally generated in the transmitter, and then a further judgment is made using the real-time voltage wave generated by the transmitting coil and capacitor in the transmitter, without increasing the complexity and cost of the wireless charging system. After two judgments, it is determined whether there are conductive foreign objects near the transmitter. In the absence of a detection coil or a receiving end load, the detection of conductive foreign objects can be completed independently. The detection dependence is small, and real-time monitoring is more convenient, which is conducive to regular inspection and protection of the transmitter (such as a charging pile, etc.).

[0073] Optionally, comparing the real-time current signal with a standard current signal to determine whether the real-time current signal is normal includes:

[0074] A standard current amplitude and a standard duty cycle are obtained according to the standard current signal.

[0075] Specifically, Figure 3 As shown in the figure, the standard current amplitude of the standard current signal is 0.05A. The duty cycle refers to the ratio of the length of time the signal is at a high level to the entire cycle in a complete cycle of the periodic waveform signal. It is used to describe the proportional relationship between the high level duration and the low level duration of the signal. Figure 3 As shown, the high level is maintained for a longer time and the duty cycle is larger.

[0076] According to the real-time current signal, a real-time current amplitude and a real-time duty cycle are obtained.

[0077] Specifically, Figure 4 As shown, the real-time current amplitude of the real-time current signal becomes 0.08A, the time for maintaining the high level is shorter, and the duty cycle becomes smaller.

[0078] When the real-time current amplitude is greater than the standard current amplitude and the real-time duty cycle is less than the standard duty cycle, the real-time current signal is determined to be abnormal. When the real-time current amplitude is equal to the standard current amplitude or the real-time duty cycle is equal to the standard duty cycle, the real-time current signal is determined to be normal.

[0079] Specifically, when the real-time current amplitude is greater than the standard current amplitude and the real-time duty cycle is less than the standard duty cycle, the real-time current signal is judged to be abnormal, indicating that a conductor appears around the transmitter. It can be preliminarily judged that there is a conductor foreign object around the transmitter, but the foreign object may be a metal foreign object or a receiving end, because both the receiving end and the metal foreign object will absorb the energy of the transmitter, causing the real-time current signal of the transmitter to change. Therefore, through preliminary judgment, it is easy to identify the presence of a conductor around the transmitter, which is convenient for subsequent judgment.

[0080] Optionally, when the real-time current signal is abnormal, after controlling the transmitting end to send a preset number of detection signals to the outside, detecting the real-time voltage wave at both ends of the transmitting component of the transmitting end comprises:

[0081] When the real-time current signal is abnormal, the transmitting end is controlled to periodically send the detection signal to the outside, and it is determined whether a feedback signal from the receiving end is received.

[0082] Specifically, the preset number of detection signals can be eight or three, which needs to be adjusted according to actual conditions, as long as there is enough electrical energy stored in the transmitting coil and capacitor in the transmitting component after the detection signal is emitted in the early stage. If the transmitting coil and capacitor do not store enough energy, the real-time voltage wave obtained subsequently will not be obvious enough.

[0083] When the feedback signal is received, it is determined that the foreign object within the radiation range of the transmitting end is a normal receiving end.

[0084] Specifically, when the real-time current signal is abnormal, it is preliminarily determined that a conductor appears around the transmitting end, and further analysis is performed on the foreign object. When a feedback signal is received from the receiving end, it indicates that the foreign object is a normal receiving end.

[0085] When the feedback signal is not received, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage waves at both ends of the transmitting component of the transmitting end are detected.

[0086] Specifically, when the feedback signal from the receiving end is not received, the real-time current signal is monitored to be abnormal. At this time, it can be basically determined that there are conductive foreign objects around the transmitting end. However, the real-time current signal abnormality may also be affected by the environment. At this time, in order to avoid misjudgment, the conductive foreign objects can be further confirmed in combination with subsequent steps. In this embodiment, by eliminating the influence of the receiving end, the conductive foreign objects that may exist at the transmitting end are more accurately checked and confirmed, which is convenient for the maintenance of the wireless charging system (such as a charging pile, etc.), and the problem of reduced charging efficiency due to the transmitting end is avoided. For the conductive foreign objects that may be introduced by the receiving end, the operator may not be able to intervene in time, and the conductive foreign objects introduced by the receiving end are temporary. When the receiving end is removed, the conductive foreign objects disappear. However, if there are conductive foreign objects at the receiving end, it will be a continuous impact, which may affect multiple receiving ends that are charged successively. Therefore, the present invention focuses on detecting and checking the conductive foreign objects introduced by the transmitting end, which has great significance for the operation and maintenance of the wireless charging system.

[0087] Optionally, obtaining, based on the real-time voltage wave and a preset threshold, the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold comprises:

[0088] The real-time voltage wave is input to the positive input terminal of the comparator to obtain a real-time comparison waveform output by the comparator, wherein the input value of the negative input terminal of the comparator is a preset threshold value.

[0089] The real-time comparison waveform is analyzed to obtain the number of high levels of the real-time comparison waveform, which is recorded as the real-time number.

[0090] Specifically, the comparator can be a single-power supply comparator, the power supply voltage of the comparator can be 20V, the low voltage terminal is grounded, and the preset threshold of the negative input terminal can be set to 10V or other values, which can be changed according to needs. The real-time comparison waveform obtained is as follows Figure 5 shown.

[0091] In this optional embodiment, because the real-time voltage wave will gradually weaken, the peak value of a certain peak may exceed the preset threshold value only for a short time, or the peak value of a certain peak may be slightly smaller than the preset threshold value, which is not easy to identify in the obtained real-time voltage wave. The real-time voltage wave is input into the comparator, and the comparator can sensitively and clearly identify the voltage greater than the preset threshold value. At this time, a high level can be accurately output, and then only the high level in the real-time comparison waveform needs to be calculated, thereby improving the accuracy of the real-time times.

[0092] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0093] Starting from the starting end of the real-time voltage wave, the peak value of the real-time voltage wave within a preset time length is picked up to obtain the real-time peak total value.

[0094] It should be noted that the real-time voltage wave is collected and detected after the detection signal is transmitted. If the detection signal appears in the waveform diagram, the detection signal part can be eliminated.

[0095] Starting from the starting end of the standard voltage wave, the peak value of the wave within the preset time length in the standard voltage wave is picked up to obtain the total standard peak value, wherein the standard voltage wave is the voltage wave at both ends of the transmitting component after the transmitting end sends a preset number of detection signals to the outside when the transmitting end is unloaded and there are no conductive foreign objects within the radiation range of the transmitting end. It should be noted that the standard voltage wave is a waveform collected and detected after the detection signal is transmitted. If a detection signal appears in the waveform diagram, the detection signal part can be eliminated.

[0096] Specifically, for example, the sum of multiple peak values ​​within 10s is calculated separately. For example, if the number of peaks within 10s is 4, the first four peak values ​​of the real-time voltage wave are added to obtain the total real-time peak value; the first four peak values ​​of the standard voltage wave are added to obtain the total standard peak value.

[0097] A first interference ratio is obtained according to the real-time peak total value and the standard peak total value, wherein the first interference ratio is used to predict the volume of the conductive foreign matter.

[0098] Specifically, the standard peak value is subtracted from the real-time peak value to obtain the peak difference, and the peak difference is divided by the standard peak value to obtain the first interference ratio. If the first interference ratio is greater than zero, it means that the conductor foreign matter affects the voltage wave, reflecting the degree to which the voltage wave is weakened. The larger the first interference ratio, the greater the degree to which the voltage wave is affected by the conductor foreign matter, and the larger the volume of the conductor foreign matter. Therefore, a corresponding relationship table between the first interference ratio and the volume of the conductor foreign matter can be set. Through advance experiments, the first interference ratio values ​​corresponding to different conductor foreign matter volumes can be tested. In the actual monitoring process, the corresponding table can be used in reverse to quickly determine the volume of the conductor foreign matter according to the first interference ratio. After obtaining the volume of the conductor foreign matter, personnel can be arranged to check for larger conductor foreign matter immediately. For smaller conductor foreign matter, the impact may be small, so the inspection can be postponed, and urgent inspection tasks can be given priority, which is convenient for the subsequent reasonable maintenance of the wireless charging system.

[0099] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0100] The duration of the high level in the real-time comparison waveform is analyzed to obtain the actual duration, wherein the actual duration is the duration from the appearance of the first high level to the end of the last high level in the real-time comparison waveform.

[0101] The standard voltage wave is input into the positive input terminal of the comparator to obtain the standard comparison waveform.

[0102] The standard duration is obtained according to the duration of the high level in the standard comparison waveform, wherein the standard duration is the duration from the appearance of the first high level to the end of the last high level in the standard comparison waveform.

[0103] Specifically, Figure 5 and Figure 6 As shown in the figure, they are the real-time comparison waveform and the standard comparison waveform. In these two waveform diagrams, the first three waveforms are rectangular waves introduced by the detection signal. These three waveforms can be removed during analysis. Figure 5 The last four waveforms in Figure 6 The last five waveforms in the figure are the real-time comparison waves and standard comparison waves collected and detected at both ends of the transmitting component after the detection signal stops. Figure 5 and Figure 6 By comparison, it can be seen that after being affected by the foreign matter in the conductor, the number of square waves in the real-time comparison wave decreases and the duration of the square wave shortens. Therefore, the duration of the real-time comparison wave can also be used to analyze the degree of influence of the foreign matter in the conductor on the voltage wave.

[0104] A second interference ratio is obtained according to the actual duration and the standard duration, wherein the second interference ratio is used to predict the volume of the conductive foreign matter.

[0105] Specifically, the standard duration is subtracted from the actual duration to obtain the duration difference, and then the duration difference is divided by the standard duration to obtain the second interference ratio. The larger the second interference ratio, the greater the impact of the conductor foreign matter on the voltage wave, indicating that the volume of the conductor foreign matter may be larger; or it indicates that after being converted into a reference conductor foreign matter (both converted into substances of the same material), the volume is larger.

[0106] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0107] According to the real-time comparison waveform and the standard comparison waveform, a first duty cycle of the real-time comparison waveform and a second duty cycle of the standard comparison waveform are correspondingly obtained.

[0108] Specifically, Figure 5As shown in the figure, the low level duration between the fourth square wave and the fifth square wave in the real-time comparison waveform is shorter, indicating that the duty cycle is larger. Figure 6 As shown in the figure, the low level duration between the fourth and fifth square waves in the standard comparison waveform is longer, indicating that the duty cycle is smaller. Figure 5 and Figure 6 In the example, excluding the first three high levels, the duty cycle corresponding to each high level can be calculated separately, which will be Figure 5 The four duty cycles calculated in are added and averaged to obtain the first duty cycle; Figure 6 The five duty cycles calculated in the above are added together and the average value is calculated to obtain the second duty cycle. Therefore, the foreign matter in the conductor has a certain influence on the duty cycle, and the foreign matter in the conductor makes the frequency of the square wave appear faster.

[0109] A third interference ratio is obtained according to the first duty cycle and the second duty cycle, wherein the third interference ratio is used to predict the volume of the conductive foreign matter.

[0110] Specifically, the first duty cycle can be subtracted from the second duty cycle to obtain the duty cycle difference, and then the duty cycle difference can be divided by the second duty cycle to obtain the third interference ratio. The larger the third interference ratio, the greater the influence of the conductor foreign matter on the voltage wave, which means that after being converted into the reference conductor foreign matter, the volume is larger, and the conductor foreign matter needs to be removed in time, so as to reasonably arrange the conductor foreign matter cleaning task.

[0111] Optionally, when the real-time number is less than a preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes:

[0112] An influence degree value is obtained according to the first interference ratio, the second interference ratio, the third interference ratio, and a preset weight corresponding to each interference ratio.

[0113] The volume and danger level of the conductive foreign matter are predicted according to the impact level value.

[0114] Specifically, since the first interference ratio is calculated based on the peak value, the second interference ratio is calculated based on the duration of the voltage wave, and the third interference ratio is calculated based on the duty cycle. The corresponding preset weights can be set according to the influence of the conductor foreign matter on the peak value, duration and duty cycle. For example, the influence of the conductor foreign matter on the three is from large to small, namely, the peak value, duration and duty cycle. At this time, the preset weight corresponding to the first interference ratio can be set larger, such as 0.6; the preset weight corresponding to the second interference ratio is set to 0.3, and the preset weight corresponding to the third interference ratio is set to 0.1. The influence degree value is obtained by integrating data from multiple aspects for calculation. The evaluation of the influence degree value will be more accurate, and it has a certain correction effect on the individual interference ratio, so that the volume and degree of danger of the conductor foreign matter obtained in the end are more realistic. In addition, the larger the influence degree value, the greater the volume and degree of danger.

[0115] like Figure 7 As shown, in an optional embodiment of the present invention, a conductor foreign body detection system for wireless charging is also provided, comprising:

[0116] The current detection module 100 is used to input a preset current to the unloaded transmitting end and detect a real-time current signal in the transmitting end.

[0117] The judgment module 200 is used to compare the real-time current signal with the standard current signal to determine whether the real-time current signal is normal, wherein the standard current signal is the current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end.

[0118] The voltage wave detection module 300 is used to control the transmitting end to send a preset number of detection signals to the outside when the real-time current signal is abnormal, and then detect the real-time voltage wave at both ends of the transmitting component of the transmitting end, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil.

[0119] The voltage wave analysis module 400 is used to obtain the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold according to the real-time voltage wave and the preset threshold.

[0120] The foreign object confirmation module 500 is used to determine that there is a conductive foreign object within the radiation range of the transmitting end when the real-time number is less than the preset number, wherein the preset number is the number of times that the voltage wave at both ends of the transmitting component exceeds a preset threshold after the transmitting end sends a preset number of detection signals to the outside when the transmitting end is unloaded and there is no conductive foreign object within the radiation range of the transmitting end.

[0121] In this embodiment, the current detection module 100 connects the transmitter to the power supply, inputs a preset current to the unloaded transmitter, and detects the real-time current signal in the transmitter; the judgment module 200 compares the real-time current signal with the standard current signal to determine whether the real-time current signal is normal. The standard current signal is the current signal in the transmitter after the preset current is input to the transmitter when the transmitter is unloaded and there is no conductive foreign matter within the radiation range of the transmitter; when the real-time current signal is abnormal, the voltage wave detection module 300 preliminarily determines that there may be conductive foreign matter near the transmitter, and controls the transmitter to send a preset number of detection signals to the outside. After that, the real-time voltage wave at both ends of the transmitting component of the transmitting end is detected, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil; since when there is a conductive foreign object near the transmitting end, part of the energy emitted by the transmitting end will be absorbed by the conductive foreign object, and the generated real-time voltage wave will be different from the voltage wave generated when there is no conductive foreign object, so the voltage wave analysis module 400 obtains the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold according to the real-time voltage wave and the preset threshold; when the real-time number is less than the preset number, the foreign object confirmation module 500 further determines that there is a conductive foreign object in the radiation range of the transmitting end. In the detection process, there is no need to add external equipment to the wireless charging device, first use the real-time current signal normally generated in the transmitting end to make a preliminary judgment, and then use the real-time voltage wave generated by the transmitting coil and the capacitor in the transmitting end to make a further judgment, without increasing the complexity and cost of the wireless charging system; after two judgments to determine whether there is a conductive foreign object near the transmitting end, without the detection coil or the introduction of the receiving end load, the detection of the conductive foreign object can be completed independently, the detection dependence is small, and it is more convenient to carry out real-time monitoring, which is conducive to the regular inspection and protection of the transmitting end.

[0122] like Figure 8 As shown, an electronic device 800 provided by an embodiment of the present invention includes a memory 820 and a processor 810; the memory 820 is used to store a computer program; the processor 810 is used to implement the foreign object detection method for wireless charging as described above when executing the computer program.

[0123] In other words, an electronic device 800 includes a memory 820 and a processor 810 coupled to the memory 820; the memory 820 is configured to store a computer program; and the processor 810 is configured to perform the following operations when executing the computer program:

[0124] Input a preset current to the unloaded transmitter and detect a real-time current signal in the transmitter;

[0125] Comparing the real-time current signal with a standard current signal to determine whether the real-time current signal is normal, wherein the standard current signal is a current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end;

[0126] When the real-time current signal is abnormal, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage wave at both ends of the transmitting component of the transmitting end is detected, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil;

[0127] According to the real-time voltage wave and the preset threshold, obtaining the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold;

[0128] When the real-time number is less than the preset number, it is determined that there is a conductive foreign object within the radiation range of the transmitting end.

[0129] In this embodiment, the beneficial effects of the electronic device 800 are the same as the beneficial effects of the foreign object detection method for wireless charging described above, and are not described in detail herein.

[0130] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the foreign object detection method for wireless charging as described above is implemented.

[0131] In other words, a non-volatile computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor performs the following operations:

[0132] Input a preset current to the unloaded transmitter and detect a real-time current signal in the transmitter;

[0133] Comparing the real-time current signal with a standard current signal to determine whether the real-time current signal is normal, wherein the standard current signal is a current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end;

[0134] When the real-time current signal is abnormal, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage wave at both ends of the transmitting component of the transmitting end is detected, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil;

[0135] According to the real-time voltage wave and the preset threshold, obtaining the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold;

[0136] When the real-time number is less than the preset number, it is determined that there is a conductive foreign object within the radiation range of the transmitting end.

[0137] In this embodiment, the beneficial effects of the readable storage medium are the same as the beneficial effects of the foreign object detection method for wireless charging described above, and will not be described in detail here.

[0138] An electronic device 800 that can be used as a server or client of the present invention will now be described, which is an example of a hardware device that can be applied to various aspects of the present invention. The electronic device 800 is intended to represent various forms of digital electronic computer equipment, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device 800 can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples, and are not intended to limit the implementation of the present invention described herein and / or required.

[0139] The electronic device 800 includes a computing unit, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) or a computer program loaded from a storage unit into a random access memory (RAM). In the RAM, various programs and data required for the operation of the device can also be stored. The computing unit, ROM, and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0140] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc. In the present application, the unit described as a separate component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place, or it may be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment of the present invention. In addition, each functional unit in each embodiment of the present invention can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0141] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A foreign object detection method for wireless charging, characterized in that: include: Input a preset current to the unloaded transmitter and detect a real-time current signal in the transmitter; Comparing the real-time current signal with a standard current signal to determine whether the real-time current signal is normal, wherein the standard current signal is a current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end; When the real-time current signal is abnormal, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage wave at both ends of the transmitting component of the transmitting end is detected, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil; According to the real-time voltage wave and a preset threshold, obtaining the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold; When the real-time number is less than the preset number, it is determined that there is a conductive foreign object within the radiation range of the transmitting end; Starting from the starting end of the real-time voltage wave, picking up the peak value of the real-time voltage wave within a preset time length to obtain a real-time peak total value; Starting from the starting end of the standard voltage wave, the peak value of the wave within the preset time length in the standard voltage wave is picked up to obtain the total standard peak value, wherein the standard voltage wave is the voltage wave at both ends of the transmitting component after the transmitting end sends a preset number of detection signals to the outside when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end; A first interference ratio is obtained according to the real-time peak total value and the standard peak total value, wherein the first interference ratio and the volume of the conductive foreign matter have a corresponding preset relationship table to predict the volume of the conductive foreign matter according to the first interference ratio.

2. The foreign object detection method for wireless charging according to claim 1, characterized in that: The comparing the real-time current signal with the standard current signal to determine whether the real-time current signal is normal comprises: According to the real-time current signal, a real-time current amplitude and a real-time duty cycle are obtained; According to the standard current signal, a standard current amplitude and a standard duty cycle are obtained; When the real-time current amplitude is greater than the standard current amplitude and the real-time duty cycle is less than the standard duty cycle, it is determined that the real-time current signal is abnormal.

3. The foreign object detection method for wireless charging according to claim 1, characterized in that: When the real-time current signal is abnormal, after controlling the transmitting end to send a preset number of detection signals to the outside, detecting the real-time voltage wave at both ends of the transmitting component of the transmitting end comprises: When the real-time current signal is abnormal, controlling the transmitting end to periodically send the detection signal to the outside, and determining whether a feedback signal from the receiving end is received; When receiving the feedback signal, determining that the foreign object within the radiation range of the transmitting end is a normal receiving end; When the feedback signal is not received, the transmitting end is controlled to send a preset number of detection signals to the outside, and then the real-time voltage waves at both ends of the transmitting component of the transmitting end are detected.

4. The foreign object detection method for wireless charging according to claim 1, characterized in that: The obtaining, according to the real-time voltage wave and the preset threshold, the real-time number of times that the peak value of the real-time voltage wave exceeds the preset threshold comprises: Inputting the real-time voltage wave to the positive input terminal of the comparator to obtain a real-time comparison waveform output by the comparator, wherein the input value of the negative input terminal of the comparator is a preset threshold value; The real-time comparison waveform is analyzed to obtain the number of high levels of the real-time comparison waveform, which is recorded as the real-time number.

5. The foreign object detection method for wireless charging according to claim 4, characterized in that: When the real-time number is less than the preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes: Analyze the duration of the high level in the real-time comparison waveform to obtain the actual duration; Inputting the standard voltage wave into the positive input terminal of the comparator to obtain a standard comparison waveform; Compare the duration of the high level in the waveform according to the standard to obtain the standard duration; A second interference ratio is obtained according to the actual duration and the standard duration, wherein the second interference ratio is used to predict the volume of the conductive foreign matter.

6. The foreign object detection method for wireless charging according to claim 5, characterized in that: When the real-time number is less than the preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes: According to the real-time comparison waveform and the standard comparison waveform, a first duty cycle of the real-time comparison waveform and a second duty cycle of the standard comparison waveform are correspondingly obtained; A third interference ratio is obtained according to the first duty cycle and the second duty cycle, wherein the third interference ratio is used to predict the volume of the conductive foreign matter.

7. The foreign object detection method for wireless charging according to claim 6, characterized in that: When the real-time number is less than the preset number, after determining that there is a conductive foreign object within the radiation range of the transmitting end, the method further includes: Obtaining an influence degree value according to the first interference ratio, the second interference ratio, the third interference ratio, and a preset weight corresponding to each interference ratio; The volume and danger level of the conductive foreign matter are predicted according to the variation trend of the impact level value.

8. A wireless charging foreign object detection system, characterized in that: include: A current detection module, used to input a preset current to the unloaded transmitter and detect a real-time current signal in the transmitter; A judgment module, used for comparing the real-time current signal with a standard current signal to judge whether the real-time current signal is normal, wherein the standard current signal is a current signal in the transmitting end after a preset current is input to the transmitting end when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end; A voltage wave detection module, used for controlling the transmitting end to send a preset number of detection signals to the outside when the real-time current signal is abnormal, and then detecting the real-time voltage wave at both ends of the transmitting component of the transmitting end, wherein the transmitting component includes a transmitting coil and a capacitor connected in series with the transmitting coil; A voltage wave analysis module, used for obtaining the real-time number of times the peak value of the real-time voltage wave exceeds the preset threshold value according to the real-time voltage wave and the preset threshold value; A foreign body confirmation module, used to determine that there is a conductive foreign body within the radiation range of the transmitting end when the real-time number is less than a preset number; The foreign body confirmation module is also used for: Starting from the starting end of the real-time voltage wave, picking up the peak value of the real-time voltage wave within a preset time length to obtain a real-time peak total value; Starting from the starting end of the standard voltage wave, the peak value of the wave within the preset time length in the standard voltage wave is picked up to obtain the total standard peak value, wherein the standard voltage wave is the voltage wave at both ends of the transmitting component after the transmitting end sends a preset number of detection signals to the outside when the transmitting end is unloaded and there is no conductive foreign matter within the radiation range of the transmitting end; A first interference ratio is obtained according to the real-time peak total value and the standard peak total value, wherein the first interference ratio and the volume of the conductive foreign matter have a corresponding preset relationship table to predict the volume of the conductive foreign matter according to the first interference ratio.

9. An electronic device, characterized in that: including memory and processor; The memory is used to store computer programs; The processor is used to implement the foreign object detection method for wireless charging according to any one of claims 1 to 7 when executing the computer program.

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