A foreign matter detection device and method based on signal coil multiplexing of high-power wireless energy

Abstract

The present application relates to wireless charging technical field, especially to a kind of based on signal coil multiplexing's large power wireless energy foreign matter detection device and method, including energy transmission module, data communication module and foreign matter detection module, the data communication module is electrically connected with energy transmission module and foreign matter detection module respectively, the energy transmission module is used to realize the wireless transmission of electric energy from direct current power supply to load, provides the required electric energy for load, the present application is reasonably laid out by signal detection coil and power coil in space, so that it can be inducted to the magnetic field change caused by metal foreign matter, also try to reduce the interference of power coil strong magnetic field to it, realizes the effect of coil multiplexing, so that it can be arranged more detection coil in limited space, to expand detection range, ensure the comprehensiveness of foreign matter detection in wireless charging area.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless charging, and in particular relates to a foreign object detection device and method based on high-power wireless energy multiplexing of signal coils. Background Art

[0002] During the wireless charging process, in order to ensure that there is no metal or other harmful objects interfering with energy transmission during the charging process, foreign object detection is required for high-power wireless energy to prevent potential safety hazards;

[0003] Currently, foreign object detection for high-power wireless energy is typically performed by measuring the change in magnetic flux and induced voltage caused by metal foreign objects in a detection coil. To achieve this, specialized detection coils are required to sense changes in the magnetic field. The design, layout, and parameter selection of these detection coils are all aimed at maximizing the capture of magnetic field changes caused by metal foreign objects, thereby ensuring detection accuracy and sensitivity.

[0004] However, the above detection method usually relies on a single or multiple fixed detection coils to monitor the changes in magnetic flux, so that the detection range is limited by the length and size of the detection coil, and may not be able to fully cover the entire wireless charging area, resulting in a detection blind spot. Therefore, we need to propose a high-power wireless energy foreign object detection device and method based on signal coil reuse to solve the above problems, so that it can arrange more detection coils in a limited space through coil reuse technology, thereby expanding the detection range and ensuring the comprehensiveness of foreign object detection in the wireless charging area. Summary of the Invention

[0005] To address the above issues, the present invention provides a high-power wireless energy foreign object detection device based on signal coil multiplexing, comprising an energy transmission module, a data communication module, and a foreign object detection module. The data communication module is electrically connected to the energy transmission module and the foreign object detection module, respectively. The energy transmission module is used to realize wireless transmission of electric energy from a DC power supply to a load, thereby providing the required electric energy to the load.

[0006] The data communication module is used to realize data communication between the primary side and the secondary side, ensuring the coordinated operation of the energy transmission module and the foreign object detection module; the data communication module includes an MCU, a primary side data transceiver circuit, and a secondary side data transceiver circuit, the MCU is electrically connected to the primary side data transceiver circuit and the secondary side data transceiver circuit, respectively, and the primary side data transceiver circuit and the secondary side data transceiver circuit are respectively located on both sides of the power coil;

[0007] The foreign object detection module is used to detect whether there is a metal foreign object in the high-power wireless energy transmission area to ensure the safe operation of the system. The foreign object detection module includes a control switch, a foreign object detection circuit, and a signal detection coil for decoupling from the power coil. One end of the control switch is connected to one end of the signal detection coil, and the other end of the signal detection coil is respectively connected to one end of the foreign object detection circuit and one end of the primary data transceiver circuit. The other end of the foreign object detection circuit and the other end of the primary data transceiver circuit are respectively connected to the other two ends of the control switch.

[0008] Furthermore, the energy transmission module includes a DC power supply, a DC-AC converter, a compensation network, a power coil and a load, the DC power supply is connected to the input end of the DC-AC converter, the power coil includes a transmitting coil and a receiving coil, the compensation network is connected to the transmitting coil and the receiving coil, and the receiving coil and the transmitting coil are both connected to the compensation network. The load is located at the other end of the compensation network at the receiving coil, and the DC-AC converter is located at the other end of the compensation network at the transmitting coil.

[0009] Furthermore, the process of wireless energy transmission by the energy transmission module is as follows:

[0010] A1. Directly provide DC voltage to the DC-AC converter through a DC power supply;

[0011] A2, DC-AC converter converts DC power into AC power according to the control signal of MCU;

[0012] A3. After the AC voltage passes through the compensation network, the transmitting coil and the receiving coil reach a resonant state;

[0013] A4. The transmitting coil generates an alternating magnetic field under the excitation of alternating current. According to Faraday's law of electromagnetic induction, the electromotive force induced in the receiving coil is calculated as follows:

[0014] Where N is the number of turns of the receiving coil, Φ is the magnetic flux, e is the electromotive force, dΦ is the change in magnetic flux Φ, and dt is the time change;

[0015] A5. The AC current induced by the receiving coil is supplied to the load after passing through the secondary compensation network. The power on the load is calculated using the following formula:

[0016] Among them, P is power, U is the effective value of the voltage across the load, R L is the resistance value of the load.

[0017] Furthermore, in step A3, the compensation network performs power compensation by connecting capacitors in series with the transmitting coil and the receiving coil. The formula for calculating the resonant frequency during power compensation is as follows:

[0018] Among them, f0 is the resonant frequency, L is the inductance of the coil, and C is the capacitance of the series capacitor. In the resonant state, the impedance of the circuit is minimum and the energy transmission efficiency is highest.

[0019] Furthermore, the process of the primary side data transceiver circuit transmitting data to the secondary side data transceiver circuit is as follows:

[0020] B1. MCU encodes the data to be sent and then modulates it through the primary data transceiver circuit;

[0021] B2. The modulated signal is transmitted through the transmitting coil, and the receiving coil of the secondary side data transceiver circuit receives the signal and amplifies and filters it;

[0022] B3. The secondary side data transceiver circuit demodulates the received signal, restores the original data signal, and then sends a handshake signal to the primary side. The primary side determines whether the handshake signal is received. If it is received, power transmission is performed. If not, the primary side continues to wait.

[0023] Furthermore, in step B1, the modulation formula of the primary data transceiver circuit is:

[0024] u s (t)=[1+m a s(t)]U cm sin(ω c t), where u s (t) is the modulated signal, m a is the modulation index, s(t) is the baseband signal, U cm is the carrier voltage amplitude, ω c t is the angular frequency.

[0025] Furthermore, the process of the foreign object detection circuit performing foreign object detection is as follows:

[0026] C1. After the foreign object detection circuit is powered on, confirm that the magnetic flux of the signal detection coil is Φ0 and perform foreign object detection through the signal detection coil;

[0027] C2. When a metal foreign object enters the vicinity of the power coil, the magnetic flux of the signal detection coil changes. The changed magnetic flux is Φ1 = Φ0 + ΔΦ, where ΔΦ is the change in magnetic flux caused by the foreign object and Φ1 is the changed magnetic flux.

[0028] C3. Calculate the induced voltage generated in the signal detection coil based on the changed magnetic flux. The calculation formula is as follows:

[0029] Among them, u i is the calculated induced voltage, N i is the number of turns of the signal detection coil, dΦ1 is the change in magnetic flux of the signal detection coil, and dt is the time change;

[0030] C4, amplifying the calculated induced voltage;

[0031] C5, filtering the amplified voltage value;

[0032] C6. Sampling the filtered voltage value through an AD converter to convert the continuous analog signal into a discrete voltage value sequence;

[0033] C7. After receiving the digital signal output by the AD converter, the MCU calculates the characteristic parameters. The calculation formula of the characteristic parameters is as follows:

[0034] Among them, A is the characteristic parameter value, M is the total number of samples, and x(n) is the input characteristic data;

[0035] C8. Compare the calculated characteristic parameters with the preset threshold value. If the characteristic parameters exceed the preset threshold value, it is determined that there is a foreign object, and corresponding measures are taken according to the system settings. If the characteristic parameters do not exceed the preset threshold value, it is determined that there is no foreign object, and the control switch is controlled to connect the primary side data transceiver circuit to the signal detection coil, entering the data communication and power transmission process.

[0036] Furthermore, in step C4, the formula for the amplification process is as follows:

[0037] Among them, u out is the amplified voltage, R f is the feedback resistor, R1 is the input resistor, u i is the induced voltage.

[0038] Furthermore, in step C5, the filtering process is performed as follows:

[0039] Y out =(1-a)u out (t-1)+a*u out (t), where a is the filter coefficient, u out (t) is the current induced voltage input value, u out (t-1) is the induced voltage input value at the previous moment, t is the time, Y out is the output value after filtering.

[0040] Based on the above description, a foreign matter detection device based on signal coil multiplexing of large power wireless energy is provided, and a foreign matter detection method based on signal coil multiplexing of large power wireless energy is also provided, which comprises the following steps:

[0041] S1, the MCU controls the switch to connect the signal detection coil to the foreign matter detection circuit, so that the signal detection coil is in a state of preparing to detect foreign matter;

[0042] S2, it is judged whether there is foreign matter, if there is foreign matter, the MCU controls the foreign matter detection state to be kept, if there is no foreign matter, then S3 is entered; in the foreign matter detection state, it is continuously monitored whether there is an exception in the working process, and if there is an exception, the equipment is closed;

[0043] S3, the MCU controls the switch, so that the primary side data transceiver circuit is connected to the signal detection coil;

[0044] S4, the secondary side data transceiver circuit receives data and decodes, and simultaneously sends a handshake signal to the primary side;

[0045] S5, it is confirmed whether the primary side receives the handshake signal sent by the secondary side, if the handshake signal is not received, the MCU controls the foreign matter detection state to be kept; if the handshake signal is received, power transmission is carried out;

[0046] S6, the signal detection coil of the secondary side is connected to the foreign matter detection circuit, it is judged whether there is foreign matter, if there is foreign matter, the MCU controls the energy transmission module to stop power transmission, if there is no foreign matter, the MCU controls the switch, so that the secondary side data transceiver circuit is connected to the signal detection coil;

[0047] S7, the primary side receives data and decodes, and simultaneously sends a handshake signal to the secondary side;

[0048] S8, it is confirmed whether the secondary side receives the handshake signal sent by the primary side, if the handshake signal is received, power transmission is carried out, and returns to S6, if the handshake signal is not received, the MCU controls the energy transmission module to stop power transmission.

[0049] The beneficial effects of the application are as follows:

[0050] 1, the signal detection coil and the power coil are reasonably arranged in space, so that the magnetic field change caused by the metal foreign matter can be sensed, and the strong magnetic field of the power coil is minimized to interfere with it, the coil multiplexing effect is realized, more detection coils can be arranged in the limited space, so that the detection range is expanded, and the comprehensiveness of foreign matter detection in the wireless charging area is ensured.

[0051] 2、The application can realize periodic foreign matter detection through the cooperation of the energy transmission module, the data communication module and the foreign matter detection module, so as to ensure the safety of the system in the whole operation process.

[0052] Additional features and advantages of the application will be set forth in the description that follows, and in part will be apparent from the description, or can be learned by practice of the application. The objectives and other advantages of the application will be realized and attained by the structure particularly pointed out in the description and claims. BRIEF DESCRIPTION OF DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0054] Figure 1 A detection device system schematic diagram according to an embodiment of the present application is shown;

[0055] Figure 2 A flow chart of wireless energy transmission by the energy transmission module according to an embodiment of the present application is shown;

[0056] Figure 3 A flow chart of data transmission from the primary data transceiver circuit to the secondary data transceiver circuit according to an embodiment of the present application is shown;

[0057] Figure 4 A detection method flow chart according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0059] The embodiment of the present application provides a large-power wireless energy foreign matter detection device based on signal coil multiplexing, which comprises a signal coil, a primary side data transceiver circuit, a secondary side data transceiver circuit, a primary side energy transmission circuit, a secondary side energy transmission circuit, a control switch, a foreign matter detection circuit and a micro control unit (MCU). Figure 1-3As shown, including energy transmission module, data communication module and foreign matter detection module, the data communication module is respectively electrically connected with energy transmission module and foreign matter detection module, the energy transmission module is used for realizing wireless transmission of electric energy from direct current power supply to load, and providing required electric energy for load;

[0060] The energy transmission module includes a direct current power supply, a DC-AC converter, a compensation network, a power coil and a load, the direct current power supply is connected with the input end of the DC-AC converter, the power coil includes a transmitting coil and a receiving coil, the compensation network is connected on the transmitting coil and the receiving coil, the compensation network is connected on the transmitting coil and the receiving coil, and the load is located at the other end of the compensation network at the receiving coil, and the DC-AC converter is located at the other end of the compensation network at the transmitting coil.

[0061] The direct current power supply provides stable direct current electric energy as the initial source of energy of the whole system; the DC-AC converter is used for converting the direct current provided by the direct current power supply into alternating current, the frequency and amplitude of the output alternating current can be adjusted according to the system requirement, and suitable alternating current power is provided for subsequent wireless energy transmission; the compensation network compensates the reactive power in the wireless energy transmission process through the combination of inductance and capacitance, so that the transmitting coil and the receiving coil reach the resonance state, thereby improving the energy transmission efficiency and the power factor; the transmitting coil generates an alternating magnetic field under the excitation of alternating current, the receiving coil receives the alternating magnetic field energy through electromagnetic induction and converts it into alternating current, thereby realizing the wireless energy transmission; and the load is used for consuming the electric energy transmitted by the receiving coil and converting the electric energy into other forms of energy, such as charging a battery and driving an electrical device.

[0062] As shown in the figure, Figure 2 The energy transmission module performs wireless energy transmission as follows:

[0063] A1, the direct current power supply directly provides direct current voltage for the DC-AC converter;

[0064] A2, the DC-AC converter converts the direct current into alternating current according to the control signal of the MCU;

[0065] A3, the alternating voltage makes the transmitting coil and the receiving coil reach the resonance state after passing through the compensation network;

[0066] The compensation network performs power compensation through the series capacitance on the transmitting coil and the receiving coil, and the calculation formula of the resonance frequency during power compensation is as follows:

[0067] Wherein, f0 is the resonance frequency, L is the inductance value of the coil, and C is the capacitance value of the series capacitance; in the resonance state, the impedance of the circuit is minimum, and the energy transmission efficiency is highest.

[0068] A4. The transmitting coil generates an alternating magnetic field under the excitation of alternating current. According to Faraday's law of electromagnetic induction, the electromotive force induced in the receiving coil is calculated as follows:

[0069] Where N is the number of turns of the receiving coil, Φ is the magnetic flux, e is the electromotive force, dΦ is the change in magnetic flux Φ, and dt is the time change;

[0070] A5. The AC current induced by the receiving coil is supplied to the load after passing through the secondary compensation network. The power on the load is calculated using the following formula:

[0071] Among them, P is power, U is the effective value of the voltage across the load, R L is the resistance value of the load.

[0072] The data communication module is used to realize data communication between the primary side and the secondary side, ensuring the coordinated work of the energy transmission module and the foreign object detection module; the data communication module includes an MCU, a primary side data transceiver circuit and a secondary side data transceiver circuit, the MCU is electrically connected to the primary side data transceiver circuit and the secondary side data transceiver circuit respectively, the primary side data transceiver circuit and the secondary side data transceiver circuit are respectively located on both sides of the power coil, and the coordination of each module is performed by the MCU, the primary side data transceiver circuit is used to send the data information of the primary side to the secondary side, and at the same time receive the data information fed back by the secondary side; the secondary side data transceiver circuit is used to cooperate with the primary side data transceiver circuit to complete two-way data communication, receive the data sent by the primary side and perform decoding processing, and at the same time feed back the information of the secondary side to the primary side.

[0073] like Figure 3 As shown, the process of the primary side data transceiver circuit transmitting data to the secondary side data transceiver circuit is as follows:

[0074] B1. MCU encodes the data to be sent and then modulates it through the primary data transceiver circuit;

[0075] The modulation formula of the primary data transceiver circuit is:

[0076] u s (t)=[1+m a s(t)]U cm sin(ω c t), where u s (t) is the modulated signal, m a is the modulation index, s(t) is the baseband signal, U cm is the carrier voltage amplitude, ω c t is the angular frequency;

[0077] B2. The modulated signal is transmitted through the transmitting coil, and the receiving coil of the secondary side data transceiver circuit receives the signal and amplifies and filters it;

[0078] B3. The secondary side data transceiver circuit demodulates the received signal, restores the original data signal, and then sends a handshake signal to the primary side. The primary side determines whether the handshake signal is received. If it is received, power transmission is performed. If not, the primary side continues to wait.

[0079] The principle of the secondary side data transceiver circuit transmitting data to the primary side data transceiver circuit is the same as the principle of the primary side data transceiver circuit transmitting data to the secondary side data transceiver circuit, and will not be repeated here.

[0080] The foreign object detection module is used to detect whether there is a metal foreign object in the high-power wireless energy transmission area to ensure the safe operation of the system. The foreign object detection module includes a control switch, a foreign object detection circuit, and a signal detection coil for decoupling from the power coil. One end of the control switch is connected to one end of the signal detection coil, and the other end of the signal detection coil is respectively connected to one end of the foreign object detection circuit and one end of the primary data transceiver circuit. The other end of the foreign object detection circuit and the other end of the primary data transceiver circuit are respectively connected to the other two ends of the control switch.

[0081] The process of the foreign body detection circuit performing foreign body detection is as follows:

[0082] C1. After the foreign object detection circuit is powered on, confirm that the magnetic flux of the signal detection coil is Φ0 and perform foreign object detection through the signal detection coil;

[0083] C2. When a metal foreign object enters the vicinity of the power coil, the magnetic flux of the signal detection coil changes. The changed magnetic flux is Φ1 = Φ0 + ΔΦ, where ΔΦ is the change in magnetic flux caused by the foreign object and Φ1 is the changed magnetic flux.

[0084] C3. Calculate the induced voltage generated in the signal detection coil based on the changed magnetic flux. The calculation formula is as follows:

[0085] Among them, u i is the calculated induced voltage, N i is the number of turns of the signal detection coil, dΦ1 is the change in magnetic flux of the signal detection coil, and dt is the time change;

[0086] C4. Amplify the calculated induced voltage. The amplification formula is as follows:

[0087] Among them, u out is the amplified voltage, R fis the feedback resistor, R1 is the input resistor, u i is the induced voltage;

[0088] C5. Filter the amplified voltage value. The filtering formula is as follows:

[0089] Y out =(1-a)u out (t-1)+a*u out (t), where a is the filter coefficient, u out (t) is the current induced voltage input value, u out (t-1) is the induced voltage input value at the previous moment, t is the time, Y out is the output value after filtering;

[0090] C6. Sampling the filtered voltage value through an AD converter to convert the continuous analog signal into a discrete voltage value sequence;

[0091] C7. After receiving the digital signal output by the AD converter, the MCU calculates the characteristic parameters. The calculation formula of the characteristic parameters is as follows:

[0092] Among them, A is the characteristic parameter value, M is the total number of samples, and x(n) is the input characteristic data;

[0093] C8. Compare the calculated characteristic parameters with the preset threshold value. If the characteristic parameters exceed the preset threshold value, it is determined that there is a foreign object, and corresponding measures are taken according to the system settings. The corresponding measures include stopping energy transmission and issuing an alarm to prevent foreign objects from damaging the system. If the characteristic parameters do not exceed the preset threshold value, it is determined that there is no foreign object, and the control switch is controlled to connect the primary side data transceiver circuit to the signal detection coil, entering the data communication and power transmission process to ensure the normal operation of the system.

[0094] By rationally arranging the signal detection coil and the power coil in space, the coil can sense the magnetic field changes caused by metal foreign objects while minimizing the interference of the strong magnetic field of the power coil. This achieves coil reuse, allowing more detection coils to be arranged within a limited space, thereby expanding the detection range and ensuring comprehensive foreign object detection within the wireless charging area. For example, the detection coil can be placed near the power coil but not overlap it. By optimizing the coil's geometry, size, and relative position, a certain degree of decoupling can be achieved, allowing the coil to be used for foreign object detection without affecting power transmission.

[0095] During system startup or initialization, the MCU first controls the control switch to connect the signal detection coil to the foreign object detection circuit for foreign object detection. If a foreign object is detected, the process is carried out according to the above foreign object detection process. If no foreign object is detected, the MCU controls the control switch to switch the coil to the data transmission circuit for data communication between the primary and secondary sides, such as sending control instructions and status information.

[0096] After completing data communication, or during power transmission, the MCU will control the control switch again at a certain time interval or according to the conditions set by the system, so that the coil is connected to the foreign object detection circuit and performs periodic foreign object detection to monitor in real time whether there is any foreign object entering the vicinity of the power coil, ensuring the safety of the system during the entire operation process.

[0097] Based on the above-described foreign body detection device based on high-power wireless energy reused by signal coils, the present invention also provides a foreign body detection method based on high-power wireless energy reused by signal coils, such as Figure 4 As shown, the following steps are included:

[0098] S1, MCU controls the control switch to connect the signal detection coil to the foreign object detection circuit, so that the signal detection coil is in a state ready to detect foreign objects;

[0099] S2: Determine whether there is a foreign object. If there is a foreign object, the MCU controls to maintain the foreign object detection state. If there is no foreign object, it enters S3. In the foreign object detection state, the working process is continuously monitored for abnormalities. If abnormalities are found, the device is shut down.

[0100] S3, MCU controls the control switch to connect the primary data transceiver circuit to the signal detection coil;

[0101] S4, the secondary side data transceiver circuit receives and decodes the data, and sends a handshake signal to the primary side at the same time;

[0102] S5. Confirm whether the primary side receives the handshake signal sent by the secondary side. If not, the MCU controls to maintain the foreign object detection state; if received, power transmission is performed.

[0103] S6. The signal detection coil on the secondary side is connected to the foreign object detection circuit to determine whether there is a foreign object. If there is a foreign object, the MCU controls the energy transmission module to stop power transmission. If there is no foreign object, the MCU controls the control switch to connect the secondary side data transceiver circuit to the signal detection coil;

[0104] S7, the primary side receives and decodes the data, and sends a handshake signal to the secondary side;

[0105] S8. Confirm whether the secondary side receives the handshake signal sent by the primary side. If the handshake signal is received, power transmission is performed and the process returns to S6. If the handshake signal is not received, the MCU controls the energy transmission module to stop power transmission.

[0106] In summary, the signal coil is used as the detection coil for foreign object detection. Through the polling method of timing control, it is regularly detected whether there is a metal foreign object on the transmitting coil. If there is a foreign object, foreign object detection is always performed without switching to data transmission. If there is no foreign object, the circuit switches to timed data transmission to determine whether there is a matching receiving coil on the secondary side. Similarly, when there is a receiving coil on the secondary side, the primary side signal coil performs foreign object detection. If there is no foreign object, the signal coil switches to data transmission. After receiving the data, the secondary side decodes it to determine whether it matches. After matching, it sends an energy demand signal to the primary side. After receiving the signal, the primary side performs wireless charging according to the secondary side's requirements. After the handshake is completed, the signal transmitting coil enters the foreign object detection stage again, and continuously monitors whether there is any abnormality in the working process. If there is an abnormality, the device is shut down.

[0107] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A foreign body detection device based on high-power wireless energy reused by signal coils, characterized by: It includes an energy transmission module, a data communication module and a foreign object detection module. The data communication module is electrically connected to the energy transmission module and the foreign object detection module respectively. The energy transmission module is used to realize wireless transmission of electric energy from a DC power supply to a load, thereby providing the required electric energy to the load. The data communication module is used to realize data communication between the primary side and the secondary side, ensuring the coordinated operation of the energy transmission module and the foreign object detection module; the data communication module includes an MCU, a primary side data transceiver circuit, and a secondary side data transceiver circuit, the MCU is electrically connected to the primary side data transceiver circuit and the secondary side data transceiver circuit, respectively, and the primary side data transceiver circuit and the secondary side data transceiver circuit are respectively located on both sides of the power coil; The foreign object detection module is used to detect whether there is a metal foreign object in the high-power wireless energy transmission area to ensure the safe operation of the system. The foreign object detection module includes a control switch, a foreign object detection circuit, and a signal detection coil for decoupling from the power coil. One end of the control switch is connected to one end of the signal detection coil, and the other end of the signal detection coil is respectively connected to one end of the foreign object detection circuit and one end of the primary side data transceiver circuit. The other end of the foreign object detection circuit and the other end of the primary side data transceiver circuit are respectively connected to the other two ends of the control switch; The process of the foreign body detection circuit performing foreign body detection is as follows: C1. After the foreign object detection circuit is powered on, confirm that the magnetic flux of the signal detection coil is Φ0 and perform foreign object detection through the signal detection coil; C2. When a metal foreign object enters the vicinity of the power coil, the magnetic flux of the signal detection coil changes. The changed magnetic flux is Φ1 = Φ0 + ΔΦ, where ΔΦ is the change in magnetic flux caused by the foreign object and Φ1 is the changed magnetic flux. C3. Calculate the induced voltage generated in the signal detection coil based on the changed magnetic flux. The calculation formula is as follows: Among them, u i is the calculated induced voltage, N i is the number of turns of the signal detection coil, dΦ1 is the change in magnetic flux of the signal detection coil, and dt is the time change; C4, amplifying the calculated induced voltage; C5, filtering the amplified voltage value; C6. Sampling the filtered voltage value through an AD converter to convert the continuous analog signal into a discrete voltage value sequence; C7. After receiving the digital signal output by the AD converter, the MCU calculates the characteristic parameters. The calculation formula of the characteristic parameters is as follows: Among them, A is the characteristic parameter value, M is the total number of samples, and x(n) is the input characteristic data; C8. Compare the calculated characteristic parameters with the preset threshold value. If the characteristic parameters exceed the preset threshold value, it is determined that there is a foreign object, and corresponding measures are taken according to the system settings. If the characteristic parameters do not exceed the preset threshold value, it is determined that there is no foreign object, and the control switch is controlled to connect the primary side data transceiver circuit to the signal detection coil, entering the data communication and power transmission process.

2. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 1, characterized in that: The energy transmission module includes a DC power supply, a DC-AC converter, a compensation network, a power coil and a load. The DC power supply is connected to the input end of the DC-AC converter. The power coil includes a transmitting coil and a receiving coil. The compensation network is connected to the transmitting coil and the receiving coil. The receiving coil and the transmitting coil are both connected to the compensation network. The load is located at the other end of the compensation network at the receiving coil. The DC-AC converter is located at the other end of the compensation network at the transmitting coil.

3. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 2, characterized in that: The process of wireless energy transmission by the energy transmission module is as follows: A1. Directly provide DC voltage to the DC-AC converter through a DC power supply; A2, DC-AC converter converts DC power into AC power according to the control signal of MCU; A3. After the AC voltage passes through the compensation network, the transmitting coil and the receiving coil reach a resonant state; A4. The transmitting coil generates an alternating magnetic field under the excitation of alternating current. According to Faraday's law of electromagnetic induction, the electromotive force induced in the receiving coil is calculated as follows: Where N is the number of turns of the receiving coil, Φ is the magnetic flux, e is the electromotive force, dΦ is the change in magnetic flux Φ, and dt is the time change; A5. The AC current induced by the receiving coil is supplied to the load after passing through the secondary compensation network. The power on the load is calculated using the following formula: Among them, P is power, U is the effective value of the voltage across the load, R L is the resistance value of the load.

4. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 3, characterized in that: In step A3, the compensation network performs power compensation by connecting capacitors in series with the transmitting coil and the receiving coil. The formula for calculating the resonant frequency during power compensation is as follows: Among them, f0 is the resonant frequency, L is the inductance of the coil, and C is the capacitance of the series capacitor. In the resonant state, the impedance of the circuit is minimum and the energy transmission efficiency is highest.

5. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 4, characterized in that: The process of the primary side data transceiver circuit transmitting data to the secondary side data transceiver circuit is as follows: B1. MCU encodes the data to be sent and then modulates it through the primary data transceiver circuit; B2. The modulated signal is transmitted through the transmitting coil, and the receiving coil of the secondary side data transceiver circuit receives the signal and amplifies and filters it; B3. The secondary side data transceiver circuit demodulates the received signal, restores the original data signal, and then sends a handshake signal to the primary side. The primary side determines whether the handshake signal is received. If it is received, power transmission is performed. If not, the primary side continues to wait.

6. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 5, characterized in that: In step B1, the modulation formula of the primary data transceiver circuit is: u s (t)=[1+m a s(t)]U cm sin(ω c t), where u s (t) is the modulated signal, m a is the modulation index, s(t) is the baseband signal, U cm is the carrier voltage amplitude, ω c t is the angular frequency.

7. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 6, characterized in that: In step C4, the formula for the amplification process is as follows: Among them, u out is the amplified voltage, R f is the feedback resistor, R1 is the input resistor, u i is the induced voltage.

8. The foreign object detection device based on high-power wireless energy and signal coil reuse according to claim 7, characterized in that: In step C5, the filtering process is performed as follows: Y out =(1-a)u out (t-1)+a*u out (t), where a is the filter coefficient, u out (t) is the current induced voltage input value, u out (t-1) is the induced voltage input value at the previous moment, t is the time, Y out is the output value after filtering.

9. A foreign object detection method based on high-power wireless energy reused by signal coils, based on the foreign object detection device based on high-power wireless energy reused by signal coils according to any one of claims 1 to 8, characterized in that: The steps include: S1, MCU controls the control switch to connect the signal detection coil to the foreign object detection circuit, so that the signal detection coil is in a state ready to detect foreign objects; S2: Determine whether there is a foreign object. If there is a foreign object, the MCU controls to maintain the foreign object detection state. If there is no foreign object, it enters S3. In the foreign object detection state, the working process is continuously monitored for abnormalities. If abnormalities are found, the device is shut down. S3, MCU controls the control switch to connect the primary data transceiver circuit to the signal detection coil; S4, the secondary side data transceiver circuit receives and decodes the data, and sends a handshake signal to the primary side at the same time; S5. Confirm whether the primary side receives the handshake signal sent by the secondary side. If not, the MCU controls to maintain the foreign object detection state; if received, power transmission is performed. S6. The signal detection coil on the secondary side is connected to the foreign object detection circuit to determine whether there is a foreign object. If there is a foreign object, the MCU controls the energy transmission module to stop power transmission. If there is no foreign object, the MCU controls the control switch to connect the secondary side data transceiver circuit to the signal detection coil; S7, the primary side receives and decodes the data, and sends a handshake signal to the secondary side; S8. Confirm whether the secondary side receives the handshake signal sent by the primary side. If the handshake signal is received, power transmission is performed and the process returns to S6. If the handshake signal is not received, the MCU controls the energy transmission module to stop power transmission.

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