Self-switching wireless power transmission system with self-excitation PP compensation and multi-parameter decoupling

Abstract

The invention provides a self-switching wireless power transmission system based on self-excitation PP compensation and multi-parameter decoupling. The system is used for solving the technical problem that an existing self-switching wireless charging system is complex in circuit structure. Comprising a transmitting end and a receiving end, the transmitting end comprises a self-excitation inverter, the receiving end comprises a self-excitation rectifier, and the self-excitation inverter and the rectifier are self-excitation push-pull circuits with the same structure; the self-excitation push-pull circuit comprises a first MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) tube and a second MOSFET tube, a gate-level self-driving circuit is connected between the first MOSFET tube and the second MOSFET tube, and the gate-level self-driving circuit controls the first MOSFET tube and the second MOSFET tube to be alternately conducted. Under the condition that an additional alternating current switch, an auxiliary circuit and a clamping circuit are not added, multi-parameter decoupling can be achieved, and meanwhile, in the load increasing process, automatic switching from a constant current CC mode to a constant voltage CV mode under ZVS can be achieved.

Description

Technical Field

[0001] This invention relates to the field of wireless power transmission, and in particular to a self-switching wireless power transmission system with self-excited PP compensation and multi-parameter decoupling. Background Technology

[0002] Wireless power transfer (WPT) technology enables the transfer of energy without electrical connections through the coupling of different types of fields. Its high degree of freedom has attracted widespread attention and has been applied in many fields such as electric vehicles, robotics, and consumer electronics. Currently, many scholars have studied the robustness of output characteristic fluctuations caused by changes in system parameters in classical magnetically coupled wireless power transfer (MC-WPT) technology. This mainly includes the significant changes in mutual inductance and leakage inductance caused by the offset of the primary and secondary coils, leading to system transfer efficiency and power fluctuations. Furthermore, when charging a typical lithium battery, to improve charging efficiency and increase battery life, a two-stage power supply mode of constant current (CC) and constant voltage (CV) is usually selected to decouple the battery from the load. During the initial charging stage, the system first supplies power to the lithium battery in the constant current (CC) stage, during which the charging voltage rises. When the lithium battery voltage rises to the preset voltage, the charging mode switches to the constant voltage (CV) stage, and the charging current decreases until charging is complete. Therefore, the switching from constant current (CC) mode to constant voltage (CV) mode in WPT systems has become one of the current hot research directions.

[0003] To address the aforementioned issues, existing research has conducted detailed studies from various perspectives, including control strategies, compensation networks, and couplers. One approach involves using a hybrid series connection of LCL and CL compensation circuits with complementary characteristics to improve the system's anti-offset capability. Another method utilizes frequency switching and hybrid clamping to achieve the self-switching process from constant current (CC) mode to constant voltage (CV) mode during the WPT system's power supply process. However, these methods suffer from overly complex circuits, hindering their application in high power density and lightweight scenarios. Summary of the Invention

[0004] The purpose of this invention is to provide a self-excited PP compensation and multi-parameter decoupling self-switching wireless power transfer system. This addresses the technical problem of the complex circuit structure in existing self-switching wireless charging systems.

[0005] A self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system includes a transmitter and a receiver. The transmitter includes a self-excited inverter, and the receiver includes a self-excited rectifier. The self-excited inverter and the rectifier are self-excited push-pull circuits with the same structure.

[0006] The self-excited push-pull circuit includes a first MOSFET and a second MOSFET, and a gate-level self-driving circuit is connected between the first MOSFET and the second MOSFET. The gate-level self-driving circuit controls the first MOSFET and the second MOSFET to conduct alternately.

[0007] Optionally, the gate-level self-driving circuit includes a first gate-level self-driving module and a second gate-level self-driving module with symmetrical structure.

[0008] The first gate-level self-driving module is connected to the gate and drain of the first MOSFET and the source of the second MOSFET, respectively. The second gate-level self-driving module is connected to the gate and drain of the second MOSFET and the source of the first MOSFET, respectively.

[0009] Optionally, both the first and second gate-level self-driving modules include a first resistor and a first diode connected in parallel, and a second resistor and a first capacitor connected in parallel.

[0010] One end of the first resistor and the first diode connected in parallel, and one end of the second resistor and the first capacitor connected in parallel, are both connected to the gate of the first or second MOSFET. The other end of the second resistor and the first capacitor connected in parallel is connected to the emitter of the first transistor and the collector of the second transistor. One end of the first resistor and the first diode connected in parallel is connected to the emitter of the second transistor and the drain of the first or second MOSFET. The base of the second transistor is connected to the anode of the second diode, and the cathode of the second diode is connected to the source of the second or first MOSFET. The second diode is used to control the switching on and off of the second or first MOSFET.

[0011] Optionally, the collector of the first transistor is connected to one end of the third resistor and then connected to the gate drive auxiliary power supply, and the other end of the third resistor is connected to the base of the first transistor and then connected to the anode of the second diode.

[0012] Optionally, the first transistor is an NPN transistor and the second transistor is a PNP transistor.

[0013] Optionally, the self-excited push-pull circuit further includes a first resonant inductor, a second resonant inductor, and a third resonant inductor;

[0014] One end of the first resonant inductor is connected to one end of the second and third resonant inductors, and the other ends of the second and third resonant inductors are respectively connected to the source of the first MOSFET and the second MOSFET.

[0015] Optionally, the transmitting end also includes a DC power supply and a primary-side compensation capacitor and a primary-side coil connected in parallel;

[0016] The two ends of the primary-side compensation capacitor and the primary-side coil connected in parallel are respectively connected to the sources of the first and second MOSFETs in the self-excited inverter. One end of the DC power supply is connected to the other end of the first resonant inductor in the self-excited inverter, and the other end of the DC power supply is connected to the drain of the first and second MOSFETs in the self-excited inverter.

[0017] Optionally, the receiving end further includes a load and a secondary-side compensation capacitor and a secondary-side coil connected in parallel;

[0018] The two ends of the secondary-side compensation capacitor and the secondary-side coil connected in parallel are respectively connected to the source of the first and second MOSFETs in the self-excited rectifier. One end of the load is connected to the other end of the first resonant inductor in the self-excited rectifier, and the other end of the load is connected to the drain of the first and second MOSFETs in the self-excited rectifier.

[0019] Because of the adoption of the above technical solution, the present invention has the following advantages:

[0020] 1. Without adding additional AC switches, auxiliary circuits, or clamping circuits, this application can not only achieve decoupling of multiple parameters, but also achieve self-switching from constant current CC mode to constant voltage CV mode under ZVS during the process of increasing load.

[0021] 2. This application meets the self-switching characteristics of the CC-CV charging mode of lithium batteries, and can autonomously track the zero-crossing point to achieve soft-switching operation within the full load range.

[0022] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0023] The accompanying drawings of this invention are described below.

[0024] Figure 1 This is a circuit diagram of the self-switching wireless power transmission system with self-excited PP compensation according to the present invention.

[0025] Figure 2 This is a circuit diagram of the self-excited push-pull circuit of the present invention.

[0026] Figure 3 This is a graph showing the variation of the coil's self-inductance, mutual inductance, and coupling system as a function of the X-axis and Z-axis offsets.

[0027] Figure 4The graphs show the system impedance gain and phase sweep curves under different resistance values ​​according to the present invention.

[0028] Figure 5 The graphs show the system impedance gain and phase sweep curves under different coupling coefficients according to the present invention.

[0029] Figure 6 This is a graph showing the output voltage and output current as a function of load under different operating conditions of the present invention.

[0030] Figure 7 This is a graph showing the output voltage and current under different air gaps according to the present invention.

[0031] Figure 8 This is a graph showing the output power of the present invention as a function of load.

[0032] Figure 9 This is a graph showing the efficiency of the present invention as a function of load. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Example:

[0035] like Figure 1 The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system shown includes a transmitter and a receiver. The transmitter includes a DC power supply, a self-excited inverter, a primary-side compensation circuit and a primary-side coil connected in sequence. The receiver includes a secondary-side coil, a secondary-side compensation circuit, a self-excited rectifier and a load connected in sequence.

[0036] like Figure 1 As shown, Figure 1 Middle U d U is the output voltage of the DC power supply. in U is the inverter output voltage of the self-excited inverter. out Let k be the load voltage and k be the primary coil voltage. p With secondary coil L s The coupling coefficient; the primary-side compensation circuit includes the primary-side compensation capacitor C. p Primary-side compensation capacitor C p and primary coil L p Parallel configuration; the secondary compensation circuit includes a secondary compensation capacitor C. s Secondary side compensation capacitor C s and secondary coil L s Parallel configuration.

[0037] In this embodiment, the self-excited inverter output voltage U in It is DC voltage U d The reflection impedance Z of a self-excited PP topology WPT system is π times that of the other system.R and input impedance Z in As shown in equations (1) and (2) respectively:

[0038]

[0039] The system's impedance gain is equal to the input impedance Z. in With output impedance Z out The real part of the ratio is shown in equation (3):

[0040]

[0041] From equation (2), it can be seen that when the imaginary part of the system's input impedance is 0, that is, when the input impedance is purely resistive, the system operates at ZPA, i.e.:

[0042] Im{Z in}=0 (4)

[0043] Solving equation (4) yields equation (5). Since the denominator cannot be equal to 0 and is more complex than the analytical expression, it is replaced by a denominator:

[0044]

[0045] In equation (5):

[0046]

[0047] Equation (5) is a cubic equation after order reduction. It can be solved using the Cardano formula, and its Δ can be obtained from equation (7):

[0048]

[0049] When Δ>0, equation (4) has one real root and two conjugate complex roots. Therefore, the WPT system automatically tracks the ZPA operating frequency ω0 with constant current CC output characteristics, as shown in equation (8):

[0050]

[0051] When Δ < 0, the WPT system automatically tracks the operating frequency of the ZPA with constant voltage CV output characteristics. Its solution has three different real roots ω1, ω2, and ω3, as shown in equations (9), (10), and (11), respectively.

[0052]

[0053] In the formula:

[0054] Based on the above analysis, the operating frequency of the proposed self-excited WPT system can be given by equation (12):

[0055]

[0056] To simplify the analysis, this application temporarily disregards the equivalent series resistance. The system output voltage U... out The expression for is given by equation (13):

[0057]

[0058] The equivalent impedance R of the rectifier in this application E It is the load R L 4 times.

[0059] As one embodiment of this application, such as Figure 2 As shown, the self-excited inverter and rectifier are self-excited push-pull circuits with the same structure.

[0060] The self-excited push-pull circuit includes a first MOSFET M1 and a second MOSFET M2. A gate-level self-driving circuit is connected between the first MOSFET M1 and the second MOSFET M2, and the gate-level self-driving circuit controls the first MOSFET M1 and the second MOSFET M2 to be turned on alternately.

[0061] like Figure 2 As shown, the gate-level self-driving circuit includes a first gate-level self-driving module and a second gate-level self-driving module with symmetrical structure.

[0062] The first gate-level self-driving module is connected to the gate and drain of the first MOSFET M1 and the source of the second MOSFET M2, respectively. The second gate-level self-driving module is connected to the gate and drain of the second MOSFET M2 and the source of the first MOSFET M1, respectively.

[0063] like Figure 2 As shown, each of the first gate-level self-driving modules includes a first resistor R1 and a first diode D1 connected in parallel, and a second resistor R3 and a first capacitor C1 connected in parallel.

[0064] One end of the parallel connection between the first resistor R1 and the first diode D1, and one end of the parallel connection between the second resistor R3 and the first capacitor C1, are both connected to the gate of the first MOSFET M1. The other end of the parallel connection between the second resistor R3 and the first capacitor C1 is connected to the emitter of the first transistor Q1 and the collector of the second transistor Q3. One end of the parallel connection between the first resistor R1 and the first diode D1 is connected to the emitter of the second transistor Q3 and the drain of the first MOSFET M1. The base of the second transistor Q3 is connected to the anode of the second diode D3. The cathode of the second diode D3 is connected to the source of the second MOSFET M2. The second diode D3 is used to control the switching on and off of the second MOSFET M2.

[0065] The collector of the first transistor Q1 is connected to one end of the third resistor R5 and then to the gate drive auxiliary power supply U. g The third resistor R5 is connected to the base of the first transistor Q1 and then to the positive terminal of the second diode D3.

[0066] like Figure 2 As shown, each of the second gate-level self-driving modules includes a first resistor R2 and a first diode D2 connected in parallel, and a second resistor R4 and a first capacitor C2 connected in parallel.

[0067] One end of the parallel connection of the first resistor R2 and the first diode D2, and one end of the parallel connection of the second resistor R4 and the first capacitor C2, are both connected to the gate of the second MOSFET M2. The other end of the parallel connection of the second resistor R4 and the first capacitor C2 is connected to the emitter of the first transistor Q2 and the collector of the second transistor Q4. One end of the parallel connection of the first resistor R2 and the first diode D2 is connected to the emitter of the second transistor Q4 and the drain of the second MOSFET M2. The base of the second transistor Q4 is connected to the anode of the second diode D4. The cathode of the second diode D4 is connected to the source of the first MOSFET M1. The second diode D4 is used to control the on / off state of the first MOSFET M1.

[0068] The collector of the first transistor Q2 is connected to one end of the third resistor R6 and then to the gate drive auxiliary power supply U. g The third resistor R6 is connected to the base of the first transistor Q2 and then to the positive terminal of the second diode D4.

[0069] like Figure 2 As shown, the self-excited push-pull circuit also includes a first resonant inductor L1, a second resonant inductor L2, and a third resonant inductor L3;

[0070] One end of the first resonant inductor L1 is connected to one end of the second resonant inductor L2 and the third resonant inductor L3, and the other ends of the second resonant inductor L2 and the third resonant inductor L3 are respectively connected to the source of the first MOSFET M1 and the second MOSFET M2.

[0071] In this embodiment, the first transistors Q1 and Q2 are NPN transistors, and the second transistors Q3 and Q4 are PNP transistors. Figure 2 This is the circuit diagram of a self-excited inverter, with the primary-side compensation capacitor C. P and primary coil L P The two ends connected in parallel are respectively connected to the sources of the first MOSFET M1 and the second MOSFET M2 in the self-excited inverter. Figure 2 Middle U in The DC power supply U d One end is connected to the other end of the first resonant inductor L1 in the self-excited inverter. Figure 2 Middle U d The DC power supply U d The other end is connected to the drain of the first MOSFET M1 and the second MOSFET M2 in the self-excited inverter.

[0072] In this embodiment, the circuitry of the self-excited rectifier is the same as that of the self-excited inverter, and the secondary-side compensation capacitor C... s and secondary coil L s The two ends connected in parallel are respectively connected to the sources of the first MOSFET M1 and the second MOSFET M2 in the self-excited rectifier (corresponding to...). Figure 2 U in in One end of the load is connected to the other end of the first resonant inductor L1 in the self-excited rectifier (corresponding to...). Figure 3 U in d The other end of the load is connected to the drain of the first MOSFET M1 and the second MOSFET M2 in the self-excited rectifier.

[0073] In this embodiment, taking a self-excited inverter as an example, L1 is the DC inductor of the circuit, and L2 and L3 are DC phase-splitting inductors; the first MOSFET M1 and the second MOSFET M2 conduct complementaryly during operation, forming self-excited oscillation; the first diodes D1 and D2 are gate protection Zener diodes to prevent the gate-source overvoltage from breaking down; the second diodes D3 and D4 provide a feedback channel for the parallel resonant network on the primary side of the system, thereby realizing the on / off control of the MOSFETs; the first resistors R1 and R2 are the leakage circuit for the parasitic capacitance of the gate-source of the switching transistors; the second resistors R3 and R4 provide a negative voltage for the first capacitors C1 and C2 connected in parallel. In this embodiment, the two types of transistors (NPN and PNP) work alternately, with each transistor working for half a cycle; when the resonant cavity voltage U in During the positive half-cycle, the feedback channel diode D3 is on and the diode D4 is off. After amplification by transistors Q1 and Q3 and the parallel RC circuit, U... GS1 When the voltage is high, the first MOSFET M1 is turned on; similarly, when the resonant cavity voltage U... in During the negative half-cycle, the feedback channel diode D4 is on and the diode D3 is off. After amplification by transistors Q2 and Q4 and the parallel RC circuit, U... GS2 When the voltage is high, the second MOSFET M2 is turned on, and the switching waveforms of the second MOSFET M2 and the first MOSFET M1 are complementary and symmetrical.

[0074] Simulation and Experiment:

[0075] S1: System simulation analysis:

[0076] S1.1: Magnetic Field Simulation Analysis: To verify the accuracy of the model proposed in this application, a circular planar coil model with a radius of 70mm, a wire diameter of 2mm, and 6 turns was first constructed. Square ferrite cores with a side length of 150mm and a thickness of 3mm were placed on each side of the coil. The vertical distance between the two coils along the Z-axis was defined as the air gap. The circular coil used in this application has symmetry, with consistent offsets in the X and Y axes; therefore, only the offset of the coupler along the X and Z axes is considered. Transmitting coil L P and receiving coil L S The structures are symmetrical, therefore their trends of change are the same. Figure 3 In diagrams (a), (b), and (c), the self-inductance L of the transmitting coil is shown below. P Transmitting coil L P and receiving coil L S The mutual inductance M between the two coils and the coupling coefficient between the two coils vary with the air gap.

[0077] Through observation Figure 3As shown in (a), the coil's self-inductance exhibits a more pronounced shift along the Z-axis than along the X-axis. Along the Z-axis, the air gap shows significant variation within the 0-30mm range, with the coil's self-inductance gradually stabilizing after a gap spacing of 30mm. Through observation... Figure 4 As shown in (b) and (c), the mutual inductance and coupling coefficient of the coil exhibit the same trend of change with offset along both the X and Z axes, decreasing as the offset increases. Therefore, in the design of a WPT system, the impact of changes in coil self-inductance and mutual inductance under offset conditions on the system output characteristics cannot be ignored.

[0078] S1.2: Constant Current and Constant Voltage Output Characteristics Analysis of the WPT System: Based on magnetic field simulation, this application constructs a simulation model of a self-excited PP compensation and multi-parameter decoupling self-switching WPT system. This model is then combined with simulation data under coupler offset conditions to further verify the accuracy of the proposed system. For example... Figure 5 As shown, with an air gap of 30mm selected, the transmitting coil L... P and receiving coil L S The self-inductance is 17.98uH, and the coupling coefficient k = 0.55. The frequency sweep curves of impedance gain and phase of the WPT system are shown when the load varies from 5 to 500Ω. Under varying load conditions, the impedance gain corresponding to the zero-crossing point of the phase is approximately 1.

[0079] Magnetic field simulations show that when the coupler shifts, its coupling coefficient will inevitably change. However, due to the presence of the magnetic core, the self-inductance of the primary and secondary sides will also change significantly and cannot be ignored. Therefore, as... Figure 6 As shown, with the load set to 20Ω, and the primary and secondary sides facing each other, the air gap varies from 0 to 115mm, the corresponding coupling coefficient k varies from 0.05 to 0.98, and the self-inductance varies from 14.91 to 52.1μH. The frequency sweep curves of impedance gain and phase of the WPT system are shown. The impedance gain is 1 when the coupling coefficient k is between 0.26 and 0.98.

[0080] S1.3: CC-CV Self-Switching Characteristics Analysis of WPT System: Based on the above analysis, the coil self-inductance and coupling coefficient vary significantly with the air gap within a certain range. Table 1 lists 10 cases considering the simultaneous variation of coil self-inductance and coupling coefficient, when the load R... L The output current and output voltage for a wide load range from 1Ω to 500Ω are as follows: Figure 6 As shown in (a)-(j).

[0081] Table 1. Coil self-inductance and coupling coefficient under different operating conditions.

[0082]

[0083] Depend onFigure 7 It can be seen that when k varies between 0.05 and 0.92, the system's output voltage eventually stabilizes at around 58V. When k is between 0.05 and 0.45, as the load increases, the system initially operates in constant current (CC) mode. In this mode, the voltage gradually increases with the load. When the switching voltage is reached, the system switches from constant current CC mode to constant voltage (CV) mode, further verifying the system's constant current CC and constant voltage CV output characteristics, as well as the system's significant CC-CV self-switching characteristic between k and 0.05. The load value at the system's switching point decreases, therefore the CC-CV characteristic is not obvious when k is large, but the output current increases with increasing k. Its advantage is that it does not require additional detection and control; CC-CV self-switching can be achieved solely based on load changes.

[0084] The above analysis shows that the WPT system proposed in this application exhibits significant tolerance in terms of coupling, load, and self-inductance, and possesses unity impedance gain by tracking the zero-crossing of the primary autonomous inverter. This also provides ZPA operation for all considered conditions.

[0085] S2: Experimental verification:

[0086] S2.1: Prototype Setup: To verify the feasibility of the proposed WPT system, this application built an experimental prototype of a self-excited PP-compensated WPT system, including a DC power supply, a self-excited inverter, primary and secondary windings, a rectifier, an electronic load, and an oscilloscope. The system input DC voltage U d The voltage is 60V, and the parallel compensation capacitors C1 and C2 are 20nF. Since the variation in the air gap (Z-axis) significantly affects the coil's self-inductance and coupling coefficient, the self-inductance and mutual inductance of the coil were measured under different air gap conditions of 20mm, 30mm, 40mm, 50mm, and 60mm for experimental verification. The relevant measured parameters of the coupler under different operating conditions are shown in Table 2.

[0087] Table 2. Coil self-inductance and coupling coefficient under different air gaps.

[0088]

[0089] S2.2: Analysis of Experimental Results: such as Figure 7 As shown, the output voltage and output current of the system vary with the load under different air gap conditions. Figure 8The air gaps in (a)-(d) are 100mm, 60mm, 40mm, and 30mm, respectively. As the coupling coefficient increases, the output current of the system in constant current CC mode increases, while the load value at the switching point decreases. When the load is small, the system operates in constant current CC mode. As the system load increases, the system autonomously switches from constant current CC mode to constant voltage CV mode. The output of the system is relatively stable in both constant current CC and constant voltage CV modes, consistent with the simulation results.

[0090] The system's output power as a function of load is shown in the following curve. Figure 9 As shown, the system's output power initially increases and then decreases with increasing load, reaching its peak at the switching point between constant current (CC) and constant voltage (CV) modes. The system's transmission power decreases with increasing air gap, with maximum transmission efficiency at an air gap of 186.9W.

[0091] The system efficiency versus load curve is as follows: ​ As shown, the system efficiency initially increases and then decreases with increasing load; at lower loads, both transmission power and efficiency are low. With air gaps of 30mm, 40mm, and 60mm, the system's operating efficiency rapidly increases to over 80%. Furthermore, the system's maximum efficiency point is near its maximum output power point, with a maximum transmission efficiency of 95.2%.

[0092] In summary, the self-excited PP compensation and multi-parameter decoupling self-switching WPT system proposed in this application can achieve constant current CC and constant voltage CV outputs independent of the load over a wide load range. Furthermore, when k is between 0.05 and 0.55, the system can autonomously switch from constant current CC mode to constant voltage CV mode according to load changes, without the need for additional detection, control, or communication modules. In addition, the system can autonomously track zero crossings, ensuring high system efficiency, and the system's maximum output power point is near its maximum efficiency. Simulation results are consistent with experimental results, demonstrating the feasibility of the proposed system.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A self-excited PP compensation and multi-parameter decoupling self-switching wireless power transfer system, comprising a transmitter and a receiver, characterized in that, The transmitting end includes a self-excited inverter, and the receiving end includes a self-excited rectifier. The self-excited inverter and the rectifier are self-excited push-pull circuits with the same structure. The self-excited push-pull circuit includes a first MOSFET and a second MOSFET, and a gate-level self-driving circuit is connected between the first MOSFET and the second MOSFET. The gate-level self-driving circuit controls the first MOSFET and the second MOSFET to conduct alternately.

2. The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 1, characterized in that, The gate-level self-driving circuit includes a first gate-level self-driving module and a second gate-level self-driving module with symmetrical structure; The first gate-level self-driving module is connected to the gate and drain of the first MOSFET and the source of the second MOSFET, respectively. The second gate-level self-driving module is connected to the gate and drain of the second MOSFET and the source of the first MOSFET, respectively.

3. The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 2, characterized in that, The first and second gate-level self-driving modules each include a first resistor and a first diode connected in parallel, and a second resistor and a first capacitor connected in parallel. One end of the first resistor and the first diode connected in parallel, and one end of the second resistor and the first capacitor connected in parallel, are both connected to the gate of the first or second MOSFET. The other end of the second resistor and the first capacitor connected in parallel is connected to the emitter of the first transistor and the collector of the second transistor. One end of the first resistor and the first diode connected in parallel is connected to the emitter of the second transistor and the drain of the first or second MOSFET. The base of the second transistor is connected to the anode of the second diode, and the cathode of the second diode is connected to the source of the second or first MOSFET. The second diode is used to control the switching on and off of the second or first MOSFET.

4. The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 3, characterized in that, The collector of the first transistor is connected to one end of the third resistor and then to the gate drive auxiliary power supply. The other end of the third resistor is connected to the base of the first transistor and then to the anode of the second diode.

5. A self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 3 or 4, characterized in that, The first transistor is an NPN transistor, and the second transistor is a PNP transistor.

6. The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 1, characterized in that, The self-excited push-pull circuit also includes a first resonant inductor, a second resonant inductor, and a third resonant inductor. One end of the first resonant inductor is connected to one end of the second and third resonant inductors, and the other ends of the second and third resonant inductors are respectively connected to the source of the first MOSFET and the second MOSFET.

7. The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 6, characterized in that, The transmitter also includes a DC power supply and a primary-side compensation capacitor and a primary-side coil connected in parallel. The two ends of the primary-side compensation capacitor and the primary-side coil connected in parallel are respectively connected to the sources of the first and second MOSFETs in the self-excited inverter. One end of the DC power supply is connected to the other end of the first resonant inductor in the self-excited inverter, and the other end of the DC power supply is connected to the drain of the first and second MOSFETs in the self-excited inverter.

8. The self-excited PP compensation and multi-parameter decoupling self-switching wireless power transmission system according to claim 6, characterized in that, The receiving end also includes a load and a secondary-side compensation capacitor and a secondary-side coil connected in parallel. The two ends of the secondary-side compensation capacitor and the secondary-side coil connected in parallel are respectively connected to the source of the first and second MOSFETs in the self-excited rectifier. One end of the load is connected to the other end of the first resonant inductor in the self-excited rectifier, and the other end of the load is connected to the drain of the first and second MOSFETs in the self-excited rectifier.

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