Inductive power transfer system and output power control method thereof

Abstract

The embodiment of the invention provides a main induction type power transmission system and an output power control method thereof, and belongs to the technical field of wireless power supply. According to the method, a secondary side phase shift control module is arranged in the inductive power transmission system, and the secondary side phase shift control module comprises a zero-cross detection sub-module, an oscillation elimination sub-module and a dead zone generation sub-module. The secondary side phase shift control module firstly performs zero-cross detection on the secondary side resonance current through the zero-cross detection sub-module to obtain a zero-cross detection signal. Then, calculating power oscillation elimination data through an oscillation elimination sub-module according to the zero-cross detection signal and an output signal obtained in advance; and finally, driving the active rectifier according to the power oscillation elimination data through a dead zone generation sub-module. Therefore, according to the method, the active rectifier can be controlled in real time through the power oscillation elimination data, so that the power oscillation of the inductive power transmission system is eliminated, and the output power of the inductive power transmission system meets the power requirement.

Description

Technical Field

[0001] The present application relates to the field of wireless power supply technology, and in particular to a main inductive power transmission system and an output power control method thereof. Background Art

[0002] Due to the resonant frequency error, the existing inductive power transmission system will cause the relative phase shift angle on both sides of the inductive power transmission system to change periodically, thereby causing power oscillation in the inductive power transmission system. The power oscillation of the inductive power transmission system will lead to low stability of the system, and may cause waste of electric energy and reduce the output efficiency of the system. Therefore, how to eliminate the power oscillation of the inductive power transmission system and improve the stability and output efficiency of the inductive power transmission system has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] The main purpose of the embodiments of the present application is to provide an inductive power transmission system and an output power control method thereof, aiming to improve the stability and output efficiency of the inductive power transmission system.

[0004] To achieve the above-mentioned purpose, a first aspect of an embodiment of the present application proposes a main inductive power transmission system, the system comprising: a DC power supply, a main converter, a main-side LC resonant unit, a secondary-side LC resonant unit, an active rectifier, a load, a main-side phase shift control module and a secondary-side phase shift control module; the DC power supply is connected to the main-side LC resonant unit through the main converter, the secondary-side LC resonant unit comprises a secondary-side inductor, the main-side LC resonant unit comprises a main-side inductor, the main-side LC resonant unit and the secondary-side LC resonant unit perform power transmission through the main-side inductor and the secondary-side inductor, and the secondary-side phase shift control module is used to adjust the power oscillation elimination data of the active rectifier switch, and control the outer phase shift angle and the inner phase shift angle according to the power oscillation elimination data; wherein, by controlling the outer phase shift angle and the inner phase shift angle, the output power of the system is controlled to meet the power requirement.

[0005] In some embodiments, the secondary side phase shift control module includes:

[0006] A zero-crossing detection submodule, wherein an input end of the zero-crossing detection submodule is electrically inductively connected to the secondary-side inductor, and is used to generate a zero-crossing detection signal according to a zero-crossing point of the secondary-side resonant current;

[0007] an oscillation elimination submodule, the input end of the oscillation elimination submodule being electrically connected to the output end of the zero-crossing detection submodule, and being used for performing secondary-side oscillation elimination processing according to the zero-crossing detection signal to obtain the power oscillation elimination data;

[0008] A dead zone generation submodule, wherein an input end of the dead zone generation submodule is electrically connected to an output end of the oscillation elimination submodule, and is used to generate a pulse width modulation signal according to the power oscillation elimination data.

[0009] In some embodiments, the zero-crossing detection submodule includes:

[0010] A first zero-crossing detection circuit, wherein an input end of the first zero-crossing detection circuit is connected to the inductor of the secondary-side LC resonance unit, and is used to detect a zero-crossing point of the secondary-side resonance current, and generate a first zero-crossing signal according to the zero-crossing point; wherein the secondary-side resonance current is generated by the secondary-side LC resonance unit;

[0011] The second zero-crossing detection circuit is used to detect the zero-crossing point of the secondary-side resonant current and generate a second zero-crossing signal according to the zero-crossing point.

[0012] In some embodiments, the active rectifier switch includes a first switch, a second switch, a third switch, and a fourth switch, and the active rectifier further includes: a first half-bridge on the secondary side and a second half-bridge on the secondary side, wherein the first switch and the second switch are located in the first half-bridge on the secondary side, and the third switch and the fourth switch are located in the second half-bridge on the secondary side, and the dead zone generation submodule includes:

[0013] a first dead zone generating circuit, wherein an input end of the first dead zone generating circuit is electrically connected to an output end of the oscillation elimination submodule, and is used to generate a first pulse width modulation signal according to the power oscillation elimination data, so as to perform switch control on the first switch and the second switch according to the first pulse width modulation signal;

[0014] A second dead zone generating circuit, wherein the input end of the second dead zone generating circuit is electrically connected to the output end of the oscillation elimination submodule, and is used to generate a second pulse width modulation signal according to the power oscillation elimination data, so as to control the switching of the third switch and the fourth switch according to the second pulse width modulation signal.

[0015] In some embodiments, the oscillation elimination submodule includes:

[0016] A synchronous trigger submodule, the input end of which is connected to the output end of the zero-crossing detection submodule, and is used to lock the phase of the secondary-side resonant current to ensure that the zero-crossing detection signal is synchronized with the secondary-side resonant current;

[0017] A closed-loop control submodule, wherein the input end of the closed-loop control module is electrically connected to the output end of the active rectifier, and is used to perform power closed-loop control according to the original output power and the preset target output power to obtain a target internal phase shift angle; wherein the original output power is detected from the output end of the active rectifier, and the target internal phase shift angle is the internal phase shift angle of the active rectifier;

[0018] A signal processing submodule, wherein the input end of the signal processing module is respectively connected to the output end of the synchronization trigger submodule and the output end of the power closed-loop control module, and the output end of the signal processing module is connected to the input end of the dead zone generation submodule, and is used to perform frequency error correction processing according to the target internal phase shift angle, the zero-crossing detection signal, the pre-acquired input power, and the target output power to obtain the power oscillation elimination data.

[0019] In some embodiments, the closed-loop control submodule includes:

[0020] A power acquisition unit, wherein an input end of the power acquisition unit is electrically connected to an output end of the active rectifier, and is used to determine an original output power according to an output signal of the output end of the active rectifier;

[0021] an error calculation unit, wherein a negative input terminal of the error calculation unit is electrically connected to an output terminal of the power acquisition unit, a positive input terminal of the error calculation unit is input with the target output power, and the error calculation unit is used to determine an output power error according to a difference between the original output power and the target output power to obtain output power error data;

[0022] A power control unit, wherein the input end of the power control unit is electrically connected to the output end of the error calculation unit, and the output end of the power control unit is electrically connected to the input end of the signal processing submodule, and is used to perform closed-loop power control according to the output power error data to obtain the target internal phase shift angle.

[0023] To achieve the above-mentioned purpose, a second aspect of an embodiment of the present application proposes an output power control method based on an inductive power transmission system, which is applied to the inductive power transmission system proposed in the first aspect, and the method includes:

[0024] Acquiring an output signal and a secondary-side resonant current of the inductive power transmission system;

[0025] Performing zero-crossing detection on the secondary-side resonant current to obtain a zero-crossing detection signal;

[0026] Calculating power oscillation elimination data according to the zero-crossing detection signal and the output signal;

[0027] The active rectifier is driven according to the power oscillation elimination data.

[0028] In some embodiments, the active rectifier includes: a first switch, a second switch, a third switch and a fourth switch, the power oscillation elimination data includes first delay data and second delay data, and the power oscillation elimination data is calculated according to the zero-crossing detection signal and the output signal to obtain the power oscillation elimination data, including:

[0029] determining an original output power according to the output signal;

[0030] Obtaining output power error data according to the difference between the original output power and the preset target output power;

[0031] Perform power closed-loop control according to the output power error data to adjust the current internal phase shift angle to obtain a target internal phase shift angle; wherein the current internal phase shift angle is the active rectifier internal phase shift angle corresponding to the zero-crossing point of the secondary-side resonant current, and the target output power corresponding to the target internal phase shift angle is the forward output power;

[0032] Selecting a target external phase shift angle from at least one candidate external phase shift angle according to the target internal phase shift angle, the target output power, and a pre-acquired input power;

[0033] Calculating the first delay data according to the target external phase shift angle and the zero-crossing detection signal; wherein the first delay data represents the next opening time of the first switch and the second switch;

[0034] The second delay data is calculated according to the first delay data and the target internal phase shift angle; wherein the second delay data represents the next opening time of the third switch and the fourth switch.

[0035] In some embodiments, selecting a target external phase shift angle from at least one candidate external phase shift angle according to the target internal phase shift angle, the target output power, and the pre-acquired input power includes:

[0036] calculating a candidate reactive power according to at least one of the candidate outer phase shift angle, the input power, the target inner phase shift angle and the target output power;

[0037] Selecting the smallest candidate reactive power from the candidate reactive powers as the target reactive power;

[0038] The target outer phase shift angle is selected from the candidate outer phase shift angles according to the target inner phase shift angle and the target reactive power.

[0039] In some embodiments, driving the active rectifier according to the power oscillation elimination data includes:

[0040] Performing a first dead zone generation process on the first delay data by a first dead zone time generation circuit to obtain a first pulse width modulation signal; wherein the first dead zone generation process is used to set a dead zone time between the first switch and the second switch so that when the first switch is turned on, the second switch will not be turned on;

[0041] The second delayed data is subjected to a second dead zone generation process by a second dead zone time generation circuit to obtain a second pulse width modulation signal; wherein the second dead zone generation process is used to set a dead zone time between the third switch and the fourth switch so that when the third switch is turned on, the fourth switch will not be turned on;

[0042] driving the first switch and the second switch to perform switching operations according to the first pulse width modulation signal;

[0043] The third switch and the fourth switch are driven to perform switching operations according to the second pulse width modulation signal.

[0044] The main inductive power transmission system and output power control method proposed in the present application are provided by setting a secondary side phase shift control module in the inductive power transmission system, connecting the output end of the secondary side phase shift control module to the first half bridge of the secondary side and the second half bridge of the secondary side respectively, and setting a zero-crossing detection submodule, an oscillation elimination submodule and a dead zone generation submodule on the secondary side phase shift control module. The secondary side phase shift control module first obtains the secondary side resonant current of the inductive power transmission system through the zero-crossing detection submodule, performs zero-crossing detection on the secondary side resonant current, obtains a zero-crossing detection signal, and then sends the zero-crossing detection signal to the oscillation elimination submodule. After receiving the zero-crossing detection signal, the oscillation elimination submodule calculates the power oscillation elimination data according to the zero-crossing detection signal and the pre-acquired output signal, and transmits the power oscillation elimination data to the dead zone generation submodule. Finally, the dead zone generation submodule drives the active rectifier according to the power oscillation elimination data. Therefore, the inductive power transmission system provided in the embodiment of the present application can control the active rectifier in real time through power oscillation elimination data, so as to eliminate the power oscillation of the inductive power transmission system by controlling the external phase shift angle and the internal phase shift angle, and minimize the reactive power of the output power of the inductive power transmission system, so as to finally make the output power of the inductive power transmission system meet the power requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a structural schematic diagram of a main inductive power transmission system provided in an embodiment of the present application;

[0046] Figure 2 is a structural schematic diagram of a secondary side shift phase control module provided in an embodiment of the present application;

[0047] Figure 3 The output power control method based on the inductive power transmission system provided in the embodiment of the present application is Figure 1 Flowchart in ;

[0048] Figure 4 yes Figure 3 Flow chart of step S303 in FIG.

[0049] Figure 5 yes Figure 4 Flow chart of step S404 in FIG.

[0050] Figure 6 yes Figure 3 Flowchart of step S304 in . DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0052] It should be noted that, although the functional modules are divided in the system schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the system or the order in the flowchart. The terms "first", "second", etc. in the specification, claims and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0054] In the existing inductive power transmission system, the switching circuits on both sides of the coupling coil require two independent phase-shift control modules, and the frequency synchronization of the phase-shift control modules is the key to maintaining the stability of the system. However, the crystal oscillators in different phase-shift control modules are inherently different. Therefore, even if the two phase-shift control modules output the same pulse width modulation signal, there will be differences in the frequency of the phase-shift control modules, that is, the resonant frequency error. The resonant frequency error between the phase-shift control modules will cause the relative phase shift angle on both sides of the inductive power transmission system to change periodically, thereby causing power oscillation in the inductive power transmission system. The power oscillation of the inductive power transmission system will lead to low stability of the system, and may cause waste of electric energy and reduce the output efficiency of the system. Therefore, how to eliminate the power oscillation of the inductive power transmission system and improve the stability and output efficiency of the inductive power transmission system has become a technical problem that needs to be solved urgently.

[0055] Based on this, an embodiment of the present application provides a main inductive power transfer (IPT) system and an output power control method thereof, aiming to improve and eliminate power oscillations of the inductive power transfer system and enhance the stability and output efficiency of the inductive power transfer system.

[0056] The IPT system and the output power control method thereof provided in the embodiments of the present application are specifically described through the following embodiments. First, the IPT system in the embodiments of the present application is described.

[0057] Figure 1 1 is an optional structural diagram of the IPT system provided in the embodiment of the present application. The inductive power transmission system provided in the embodiment of the present application includes an energy transmitting module and an energy receiving module. The energy transmitting module includes a DC power supply (whose DC input voltage is V dc ), primary side DC capacitor C dp , main converter and main side LC resonant unit. The energy receiving module includes a secondary side LC resonant unit, an active rectifier, a secondary side DC capacitor C connected in sequence. ds , load (the load resistance is R load , the load voltage is V load ). The main side LC resonant unit adopts the main side capacitor C in series p , primary side inductance L p and the internal resistance of the primary coil R p The secondary side LC resonant unit uses a secondary side capacitor C in series s , secondary side inductance L s and the secondary coil internal resistance R s The DC power supply is connected to the primary side LC resonant unit through the main converter, and the primary side LC resonant unit and the secondary side LC resonant unit are connected through the primary side inductor L p and the secondary side inductor L sPower transmission is performed. The main converter is composed of a first half-bridge HB-A on the main side and a second half-bridge HC-B on the main side. The first half-bridge HB-A on the main side is composed of main side switches S1 and S2, and the second half-bridge HC-B on the main side is composed of main side switches S3 and S4; wherein, the switching state of the main side switch S1 represents the phase of the first half-bridge HB-A on the main side. The active rectifier is composed of a first half-bridge HB-C on the secondary side and a second half-bridge HC-D on the secondary side. The first half-bridge on the secondary side is composed of a first switch Q1 and a second switch Q2, and the second half-bridge on the secondary side is composed of a third switch Q3 and a fourth switch Q4; wherein, the switching state of the first switch Q1 represents the phase of the first half-bridge HB-C on the secondary side, and the switching state of the third switch Q3 represents the phase of the second half-bridge HB-D on the secondary side. The energy transmission module also includes a main side phase shift control module 1000, which controls the phase of the second half-bridge HB-D on the secondary side at the main side resonant frequency f p Output the main side pulse width modulation signal, the output end of the main side phase shift control module 1000 is connected to the main side first half bridge HB-A and the main side second half bridge HC-B respectively, and is used to control the phase difference between the main side first half bridge HB-A and the main side second half bridge HC-B to be 180°, wherein the phase of the main side first half bridge HB-A is the reference phase. The phase difference between the phase of the secondary side first half bridge HB-C and the phase of the main side first half bridge HB-A is determined by the current external phase shift angle θ ps Indicates that the phase difference between the phase of the first half bridge HB-C on the secondary side and the phase of the second half bridge HB-D on the secondary side is expressed by the current internal phase shift angle θ s Indicates that, where the current external phase shift angle θ ps The phase shift range is 0°-360°, and the current internal phase shift angle θ s The phase shift range is 0°-180°. The energy receiving module also includes a secondary side phase shift control module 2000, which controls the secondary side phase shift control module 2000 at the secondary side resonant frequency f s Output secondary side pulse width modulation signal, the output end of the secondary side phase shift control module 2000 is connected to the secondary side first half bridge HB-C and the secondary side second half bridge HC-D respectively, for controlling the current external phase shift angle θ ps and the current internal phase shift angle θ s Between points a and b of the main converter is the main converter AC voltage Vab, and the main converter has a main side resonant current i p The active rectifier AC voltage V is between points c and d of the active rectifier. cd , the active rectifier has a secondary side resonant current i s The secondary side phase shift control module 2000 is used to adjust the first delay data Ψ of the active rectifier switch c and the second delayed data Ψ d , and controls the current external phase shift angle θ according to the first delay data ps, and according to the first delay data Ψ c and the second delayed data Ψ d Control the current internal phase shift angle θ s ; Among them, by controlling the current external phase shift angle θ ps and the current internal phase shift angle θ s , to control the output power of the system to meet the power requirements.

[0058] like Figure 2 As shown, in some embodiments, the secondary side phase shift control module 2000 includes: a zero-crossing detection submodule 2100, an oscillation elimination submodule 2200 and a dead zone generation submodule 2300. The input end of the zero-crossing detection submodule 2100 is connected to the secondary side inductor L s Make an inductive connection to determine the secondary side resonant current i s The zero crossing point of generates a zero crossing detection signal.

[0059] In some embodiments, the zero-crossing detection submodule 2100 is responsible for detecting the secondary side inductance L s The secondary side resonant current i s , and on the secondary side the resonant current i s When the secondary side resonant current i passes through the zero point, a zero-crossing detection signal is issued. The zero-crossing point refers to the secondary side resonant current i s The moment when the secondary side resonant current i drops from the positive maximum value to zero or rises from the negative maximum value to zero. s When the zero-crossing point of φ2200 is reached, the zero-crossing detection signal can be transmitted to the oscillation elimination submodule 2200.

[0060] In some embodiments, the zero-crossing detection submodule 2100 includes: a first zero-crossing detection circuit and a second zero-crossing detection circuit. Those skilled in the art may select existing zero-crossing detection circuits as the first zero-crossing detection circuit and the second zero-crossing detection circuit according to actual conditions, and this application does not impose any specific restrictions. The input end of the first zero-crossing detection circuit is connected to the inductor L of the secondary-side LC resonant unit. s Connection for detecting the secondary side resonant current i s The zero-crossing point of the secondary side resonant current i s Produced by the secondary side LC resonant unit.

[0061] The first zero-crossing detection circuit is a part of this submodule, and its input end is electrically connected to the secondary side inductor L of the secondary side LC resonant unit. s and the secondary side capacitor C s The first zero-crossing detection circuit is used to detect the secondary side resonant current i s and generates a first zero-crossing signal according to the zero-crossing point.

[0062] The input end of the second zero-crossing detection circuit is also electrically connected to the secondary side inductor L s and the secondary side capacitor C s The function of the second zero-crossing detection circuit is the same as that of the first zero-crossing detection circuit, and is also used to detect the secondary side resonant current i s The second zero-crossing detection circuit works independently of the first zero-crossing detection circuit to generate a second zero-crossing signal. This design can improve the redundancy and reliability of the system and ensure that the system can still correctly detect the zero-crossing point even if one detection circuit fails.

[0063] In some embodiments, the input end of the dead zone generation submodule 2300 is electrically connected to the output end of the oscillation elimination submodule 2200, and is used to receive the power oscillation elimination data generated by the oscillation elimination submodule 2200, and generate a secondary side pulse width modulation (PWM) signal according to the power oscillation elimination data. The frequency of the secondary side PWM signal is the secondary side resonant frequency f s , when there is no power oscillation in the IPT system, the secondary side resonant frequency f s , system resonant frequency f0 and main side resonant frequency f p The secondary-side PWM signal is a key signal for controlling power electronic switch devices, which determines the on and off time of the first switch Q1, the second switch Q2, the third switch Q3 and the fourth switch Q4, thereby controlling the energy transmission on the energy receiving module. The dead zone generation submodule 2300 is used to ensure that an appropriate dead zone time is introduced into the secondary-side PWM signal to prevent two switch devices on the same bridge arm from being turned on at the same time, thereby preventing the components in the IPT system from being seriously damaged.

[0064] In some embodiments, the dead zone generation submodule 2300 includes: a first dead zone generation circuit and a second dead zone generation circuit. Those skilled in the art may select existing dead zone generation circuits as the first dead zone generation circuit and the second dead zone generation circuit according to actual conditions, and this application does not limit this. The input end of the first dead zone generation circuit is electrically connected to the output end of the oscillation elimination submodule 2200, and is used to generate a first pulse width modulation signal according to the power oscillation elimination data. The first pulse width modulation signal is used to control the switching control of the first switch Q1 and the second switch Q2, so as to control the first switch Q1 and the second switch Q2 to be turned on or off at a specific time, thereby controlling the flow of energy in the IPT system. The design of the second dead zone generation circuit is similar to that of the first dead zone generation circuit, and its input end is also connected to the output end of the oscillation elimination submodule 2200, and uses the same power oscillation elimination data. The second dead zone generation circuit generates a second pulse width modulation signal for controlling the switching operation of the third switch Q3 and the fourth switch Q4.

[0065] In some embodiments, the oscillation elimination submodule is electrically connected to the output end of the zero-crossing detection submodule 2100, and is used to perform secondary-side oscillation elimination processing according to the zero-crossing detection signal, and finally generate power oscillation elimination data to reduce or eliminate power oscillation in the system.

[0066] In some embodiments, the oscillation elimination submodule 2200 includes: a synchronization triggering submodule 2210 , a closed-loop control submodule 2220 , and a signal processing submodule 2230 .

[0067] The input end of the synchronous trigger submodule 2210 is connected to the output end of the zero detection submodule. After receiving the zero-crossing detection signal, the synchronous trigger submodule 2210 locks the secondary side resonant current i s phase, ensuring that the zero-crossing detection signal is consistent with the secondary-side resonant current i s By synchronizing the trigger submodule 2210, the oscillation elimination submodule 2200 can ensure that the zero-crossing detection signal is synchronized with the secondary-side resonant current i s Maintaining synchronization to reduce the time error between outputting the first pulse width modulation signal and the second pulse width modulation signal is the key to achieving effective energy transmission and avoiding unnecessary energy loss.

[0068] The input end of the closed-loop control submodule 2220 is electrically connected to the output end of the active rectifier, and is used to control the output power P according to the original output power P and the preset target output power P ref Perform power closed-loop control to obtain the target internal phase shift angle θ s The original output power P is calculated based on the output signal detected at the output end of the active rectifier, and the target internal phase shift angle θ s The phase difference between the phase of the first half bridge HB-C on the secondary side and the phase of the second half bridge HB-D on the secondary side is adjusted so that after the phase difference between the phase of the first half bridge HB-C on the secondary side and the phase of the second half bridge HB-D on the secondary side is adjusted, the target output power P of the system ref is the forward output power.

[0069] The input end of the signal processing submodule 2230 is connected to the output end of the synchronization trigger submodule and the output end of the closed-loop control submodule 2220 respectively, and the output end of the signal processing submodule 2230 is connected to the input end of the dead zone generation submodule 2300. The signal processing submodule 2230 is used to generate a phase shift angle θ' according to the target. s , zero-crossing detection signal, pre-acquired input power, target output power P ref Frequency error correction processing is performed to obtain power oscillation elimination data, so as to adjust the resonant frequency between the secondary side phase shift control modules of the IPT system according to the power oscillation elimination data, and reduce the resonant frequency error between the primary side phase shift control module and the secondary side phase shift control module.

[0070] In some embodiments, the closed-loop control submodule 2220 includes: a power acquisition unit (not shown in the figure), an error calculation unit 2221 and a power control unit 2222. The input end of the power acquisition unit is electrically connected to the output end of the active rectifier, and is used to determine the original output power P according to the output signal of the output end of the active rectifier. The output signal includes a load voltage V load , load current i load and the load voltage V load , load current i load The original output power P depends on the load voltage V load , load current i load and the load voltage V load , load current i load The negative input terminal of the error calculation unit 2221 is electrically connected to the output terminal of the power acquisition unit, and is used to receive the original output power P output by the power acquisition unit; the positive input terminal of the error calculation unit 2221 is used to receive the input target output power P ref By calculating the original output power P and the target output power P ref The error calculation unit 2221 can determine the output power error and generate output power error data. The power control unit 2222, the input end of the power control unit 2222 is electrically connected to the output end of the error calculation unit 2221, and the output end of the power control unit 2222 is electrically connected to the input end of the signal processing submodule 2230, for performing closed-loop power control according to the output power error data to obtain the target internal phase shift angle θ' s .

[0071] In some embodiments, the core element of the power control unit 2222 is a proportional-integral (PI) controller. The PI controller combines proportional control and integral control mechanisms. The proportional part responds to the current output power error data, and the integral part responds to the past accumulated output power error data to adjust the current internal phase shift angle θ of the main controller. s Adjust to get the target internal phase shift angle θ' s , so that the oscillation elimination submodule 2200 can be based on the target internal phase shift angle θ' s Generate target external phase shift angle θ' ps Finally, according to the target internal phase shift angle θ' s Generate target external phase shift angle θ' ps Generate power oscillation elimination data to effectively optimize the efficiency and stability of IPT system power transmission while reducing power oscillations in the system.

[0072] like Figure 3As shown, the embodiment of the present application also provides an output power control method based on an inductive power transmission system, which is applied to the above-mentioned inductive power transmission system. The method includes but is not limited to steps S301 to S304:

[0073] Step S301, obtaining an output signal and a secondary-side resonant current of an inductive power transmission system;

[0074] Step S302, performing zero-crossing detection on the secondary-side resonant current to obtain a zero-crossing detection signal;

[0075] Step S303, calculating power oscillation elimination data according to the zero-crossing detection signal and the output signal;

[0076] Step S304: driving the active rectifier according to the power oscillation elimination data.

[0077] In the steps S301 to S304 shown in the embodiment of the present application, the output signal of the inductive power transmission system and the secondary side resonant current i are obtained. s , then the secondary side resonant current i s Zero-crossing detection is performed to obtain a zero-crossing detection signal, and power oscillation elimination data is calculated according to the zero-crossing detection signal and the output signal, and finally the active rectifier is driven according to the power oscillation elimination data. Therefore, the output power control method based on the inductive power transmission system shown in the embodiment of the present application can monitor the operating state of the IPT system in real time, and according to the output signal of the IPT system and the secondary side resonant current i s Generate power oscillation elimination data to prevent power oscillation in the IPT system, thus ensuring that the system can transfer energy efficiently and stably.

[0078] In step S301 of some embodiments, the output signal of the inductive power transmission system includes a load voltage V load , load current i load and the load voltage V load , load current i load In the IPT system shown in the embodiment of the present application, the secondary side resonant current i s can be regarded as a constant current source, and the secondary side resonant current i s The phase lags 90° behind that of HB-A.

[0079] In step S303 of some embodiments, zero-crossing detection is used to detect the secondary-side resonant current i s When the oscillation elimination submodule 2200 receives a zero-crossing detection signal when passing through the zero point, the secondary side resonant current i can be determined by analyzing at least one zero-crossing detection signal. sAt each moment, the oscillation elimination submodule 2200 is configured to eliminate the secondary side resonant current i s The power oscillation elimination data is calculated from the phase and output signal at each moment.

[0080] In step S304 of some embodiments, the on and off times of the first switch Q1, the second switch Q2, the third switch Q3 and the fourth switch Q4 are controlled at specific times according to the power oscillation elimination data, so that the secondary side resonant frequency f s , system resonant frequency f0 and main side resonant frequency f p The error between them is the impact brought to the IPT system, so as to make the IPT system work in a stable state and reduce the power loss inside the IPT system.

[0081] See also Figure 4 In some embodiments, the power oscillation elimination data includes a first delay data Ψ c and the second delayed data Ψ d Step S303 may include but is not limited to steps S401 to S406:

[0082] Step S401, determining the original output power according to the output signal;

[0083] Step S402, obtaining output power error data according to the difference between the original output power and the preset target output power;

[0084] Step S403, performing power closed-loop control according to the output power error data to adjust the current internal phase shift angle to obtain a target internal phase shift angle; wherein the current internal phase shift angle is the internal phase shift angle of the active rectifier corresponding to the zero-crossing point of the secondary-side resonant current, and the target output power corresponding to the target internal phase shift angle is the forward output power;

[0085] Step S404, selecting a target external phase shift angle from at least one candidate external phase shift angle according to the target internal phase shift angle, the target output power, and the pre-acquired input power;

[0086] Step S405, calculating first delay data according to the target external phase shift angle and the zero-crossing detection signal; wherein the first delay data represents the next opening time of the first switch and the second switch;

[0087] Step S406, calculating second delay data according to the first delay data and the target internal phase shift angle; wherein the second delay data represents the next opening time of the third switch and the fourth switch.

[0088] In step S401 of some embodiments, according to the load voltage V load , load current i load and the load voltage V load , load current iload The phase difference between them can be used to calculate the original output power P of the IPT system. The original output power P represents the active output power currently output by the IPT system.

[0089] In step S402 of some embodiments, the preset target output power P ref is the expected output power of the IPT system, the target output power P ref The specific value of can be set according to the needs of those skilled in the art. The output power error data is used to perform power closed-loop control to adjust the current internal phase shift angle θ of the main controller. s Adjust to get the target internal phase shift angle θ' s .

[0090] In step S403 of some embodiments, the secondary side phase shift control module 2000 outputs the secondary side resonant frequency f s The secondary side PWM signal can control the on and off time of the first switch Q1 and the third switch Q3, so the secondary side resonant frequency f s The phase of the first switch Q1 and the third switch Q3 is converted into the phase. Based on this, the secondary side resonant frequency f can be adjusted by controlling the size of the external phase shift angle and the internal phase shift angle. s , to change the phase of the first switch Q1 and the third switch Q3 so that the secondary side resonant frequency f s , system resonant frequency f0 and main side resonant frequency f p equal, reducing or even eliminating the power oscillation of the IPT system. ref The IPT system will maintain a stable working state only when the output power is positive. Therefore, when the power closed-loop control is performed according to the output power error data, the target output power P ref The forward output power is set as one of the conditions for closed-loop control so that the current internal phase shift angle θ s The target internal phase shift angle θ' obtained after adjustment s , which can ensure that the IPT system remains stable.

[0091] In step S404 of some embodiments, according to the target internal phase shift angle θ' s 、Target output power P ref , the input power obtained in advance selects the target external phase shift angle θ' from at least one candidate external phase shift angle ps , can be achieved by shifting the target external phase by an angle θ' ps Replace the current external phase shift angle θ ps In the form of, the reactive power of the system can be controlled.

[0092] In step S405 of some embodiments, according to the target external phase shift angle θ'ps and the zero-crossing detection signal to calculate the first delay data Ψ c Among them, the first delay data Ψ c Characterizes the next turn-on time of the first switch Q1 and the second switch Q2 of the active rectifier. Specifically, due to the secondary side resonant current i s The phase of HB-A lags behind by 90°. ps and the zero-crossing detection signal to calculate the first delay data Ψ c When the first delay data Ψ c Set to:

[0093] Ψ C =θ' ps -90°.

[0094] In step S406 of some embodiments, according to the first delay data Ψ c and the target internal phase shift angle θ' s The second delay data Ψ can be calculated d Among them, the second delay data Ψ d Indicates the next turn-on time of the third switch Q3 and the fourth switch Q4 of the active rectifier. Specifically, the second delay data Ψ d The calculation formula can be expressed as:

[0095] Ψ D =Ψ C +θ' s .

[0096] In the steps S401 to S406 of the embodiment of the present application, the original output power P is first determined according to the output signal, and the original output power P is determined according to the preset target output power P. ref Then, the power closed-loop control is performed according to the output power error data to adjust the current internal phase shift angle θ s , get the target internal phase shift angle θ' s , the phase shift angle θ' within the target s The corresponding target output power P ref is the forward output power. Then, according to the target internal phase shift angle θ' s 、Target output power P ref , the input power obtained in advance selects the target external phase shift angle θ' from at least one candidate external phase shift angle ps Finally, according to the target external phase shift angle θ' ps and the zero-crossing detection signal to calculate the first delay data Ψ c , and according to the first delay data Ψ c and the target internal phase shift angle θ' s Calculate the second delay data Ψd , to pass the first delayed data Ψ c Control the next opening time of the first switch Q1 and the second switch Q2 of the active rectifier, the second delay data Ψ d Therefore, the output power control method based on the inductive power transmission system shown in the embodiment of the present application can control the output power of the active rectifier according to the original output power P, the preset target output power P ref and the zero-crossing detection signal to calculate the first delay data Ψ c and the second delayed data Ψ d , so that the IPT system can be based on the first delay data Ψ c and the second delayed data Ψ d The next turn-on time of the first switch Q1 , the second switch Q2 , the third switch Q3 and the fourth switch Q4 are controlled respectively, thereby achieving accurate output power control, optimizing energy transmission efficiency and ensuring system stability.

[0097] See also Figure 5 In some embodiments, step S404 may include but is not limited to steps S501 to S503:

[0098] Step S501, calculating candidate reactive power according to at least one candidate external phase shift angle, input power, target internal phase shift angle and target output power;

[0099] Step S502, selecting the smallest candidate reactive power from the candidate reactive powers as the target reactive power;

[0100] Step S503: selecting a target external phase shift angle from candidate external phase shift angles according to the target internal phase shift angle and the target reactive power.

[0101] In step S501 of some embodiments, when the target internal phase shift angle θ of the IPT system is s After determination, different current external phase shift angles θ ps This will cause the output power of the IPT system to lose to varying degrees, which is represented by reactive power Q. Specifically, when HB-C is ahead of HB-A, if The output power loss of the IPT system is the largest, and the output power of the IPT system is less than or equal to 0: The output power loss of the IPT system is the smallest, and the output power of the IPT system is the largest. When HB-C lags behind HB-A, if The output power loss of the IPT system is the largest, and the output power of the IPT system is less than or equal to 0. On this basis, the target internal phase shift angle θ' s At least one candidate external phase shift angle is selected, and the target internal phase shift angle θ' is calculated based on each candidate external phase shift angle, input power, and target internal phase shift angle θ'.s and the target output power P ref Calculate the candidate reactive power of the system. Specifically, first, according to each candidate external phase shift angle, the target internal phase shift angle θ' s The candidate output voltage V when the IPT system is in steady state is calculated based on the basic parameters of each component of the IPT system. load_st , and then according to the secondary side resonant current i s and the candidate output voltage V load_st Calculate candidate reactive power for the IPT system. Calculate candidate output voltage V load_st The specific process can be divided into three situations.

[0102] The first case is: ps =-90°, and θ' s +θ ps =90°. At this time, the candidate output voltage V load_st The specific calculation process can be expressed as:

[0103]

[0104] Among them, θ p Represents the phase difference between HB-B and HB-A, M ps is the mutual inductance between the primary side capacitor Lp and the secondary side inductor Ls, i load_ave represents the candidate load current, and the candidate load current is based on when the IPT system is stable, i rec_ave =i load_ave ,i rec_ave Represents a constant current i rec The average value of (t).

[0105] In the first case, the candidate load current i rec_ave and constant current i rec The calculation process of (t) is expressed as follows:

[0106]

[0107] Wherein, k represents that the secondary side resonant current is is in the kth cycle.

[0108] The second case is: Among them, θ C_rec is the phase difference between HB-C and HB-A, θ D_rec is the phase difference between HB-D and HB-A. At this time, the candidate output voltage V load_st , candidate load current i rec_ave and constant current i rec The specific calculation process of (t) can be expressed as:

[0109]

[0110] The third situation is: and At this time, the candidate output voltage V load_st , candidate load current i rec_ave and constant current i rec The specific calculation process of (t) can be expressed as:

[0111]

[0112] In step S502 of some embodiments, since the output power of the IPT system needs to be maximized and the reactive power Q needs to be minimized, the smallest candidate reactive power needs to be selected from the candidate reactive powers as the target reactive power.

[0113] In step S503 of some embodiments, since the candidate reactive power is calculated based on the candidate external phase shift angle, when the target reactive power is determined, the candidate external phase shift angle corresponding to the target reactive power can be selected as the target external phase shift angle θ ps .

[0114] Steps S501 to S503 shown in the embodiment of the present application are performed by calculating the phase shift angle according to at least one candidate external phase shift angle, input power, target internal phase shift angle θ' s and the target output power P ref Calculate the candidate reactive power of the system, then select the smallest candidate reactive power from the candidate reactive power as the target reactive power, and calculate the target reactive power according to the target internal phase shift angle θ' s The target reactive power is selected from the candidate external phase shift angles to determine the target external phase shift angle θ' ps , the IPT system can minimize reactive power by dynamically controlling the external phase shift angle during operation. Therefore, the output power control method based on the inductive power transmission system shown in the embodiment of the present application can improve the efficiency of power transmission inside the IPT system, reduce power loss, and thus reduce the energy loss of the IPT system.

[0115] See also Figure 6 In some embodiments, step S304 may include but is not limited to steps S601 to S604:

[0116] Step S601, performing a first dead zone generation process on the first delayed data by a first dead zone generation circuit to obtain a first pulse width modulation signal; wherein the first dead zone generation process is used to set a dead zone time between the first switch and the second switch so that when the first switch is turned on, the second switch will not be turned on;

[0117] Step S602, performing a second dead zone generation process on the second delayed data by a second dead zone time generating circuit to obtain a second pulse width modulation signal; wherein the second dead zone generation process is used to set a dead zone time between the third switch and the fourth switch so that when the third switch is turned on, the fourth switch will not be turned on;

[0118] Step S603, driving the first switch and the second switch to perform switching operations according to the first pulse width modulation signal;

[0119] Step S604: driving the third switch and the fourth switch to perform switching operations according to the second pulse width modulation signal.

[0120] In steps S601 to S604 shown in the embodiment of the present application, firstly, a first pulse width modulation signal is obtained by performing a first dead zone generation processing on the first delayed data, and a second dead zone generation processing is performed on the second delayed data to obtain a second pulse width modulation signal, and then the first switch and the second switch are driven to perform switching operations according to the first pulse width modulation signal, and the third switch and the fourth switch are driven to perform switching operations according to the second pulse width modulation signal. The output power control method based on the inductive power transmission system shown in the embodiment of the present application can ensure the correct switching timing of the first switch Q1, the second switch Q2, the third switch Q3 and the fourth switch Q4, prevent the first switch Q1 and the second switch Q2 from being turned on at the same time, or prevent the third switch Q3 and the fourth switch Q4 from being turned on at the same time, thereby extending the service life of each component of the system and ensuring the stable operation of the system.

[0121] The main inductive power transmission system and output power control method provided by the embodiment of the present application are provided by setting a secondary side phase shift control module in the IPT system, connecting the output end of the secondary side phase shift control module to the first half bridge HB-C of the secondary side and the second half bridge HC-D of the secondary side respectively, and setting a zero crossing detection submodule 2100, an oscillation elimination submodule 2200 and a dead zone generation submodule 2300 on the secondary side phase shift control module. The secondary side phase shift control module first obtains the secondary side resonant current is of the inductive power transmission system through the zero crossing detection submodule 2100, and generates a signal for the secondary side resonant current i sZero-crossing detection is performed to obtain a zero-crossing detection signal, and then the zero-crossing detection signal is sent to the oscillation elimination submodule 2200. After receiving the zero-crossing detection signal, the oscillation elimination submodule 2200 calculates the power oscillation elimination data according to the zero-crossing detection signal and the pre-acquired output signal, and transmits the power oscillation elimination data to the dead zone generation submodule 2300. Finally, the dead zone generation submodule 2300 drives the active rectifier according to the power oscillation elimination data. Therefore, the inductive power transmission system provided in the embodiment of the present application can control the active rectifier in real time through the power oscillation elimination data, so as to eliminate the power oscillation of the IPT system by controlling the outer phase shift angle and the inner phase shift angle, and minimize the reactive power of the output power of the IPT system, so that the output power of the IPT system meets the power requirement.

[0122] The embodiments described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Those skilled in the art will appreciate that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0123] Those skilled in the art will appreciate that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or a combination of certain steps, or different steps.

[0124] The system embodiments described above are merely illustrative, and the units described as separate components may or may not be physically separated, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0125] Those skilled in the art will appreciate that all or some of the steps in the methods disclosed above, and the functional modules / units in the systems and devices may be implemented as software, firmware, hardware, or a suitable combination thereof.

[0126] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0127] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "At least one of the following (items)" or similar expressions refers to any combination of these items, including any combination of single items (items) or plural items (items). For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0128] In the several embodiments provided in the present application, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are only schematic. For example, the division of the above units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of systems or units, which can be electrical, mechanical or other forms.

[0129] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0130] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0131] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but the scope of the rights of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present invention should be within the scope of the rights of the present invention.

Claims

1. An inductive power transmission system, characterized in that: The system includes a DC power supply, a main converter, a main-side LC resonant unit, a secondary-side LC resonant unit, an active rectifier, a load, a main-side phase shift control module and a secondary-side phase shift control module; the DC power supply is connected to the main-side LC resonant unit through the main converter, the secondary-side LC resonant unit includes a secondary-side inductor and a secondary-side capacitor, the main-side LC resonant unit includes a main-side inductor, the main-side LC resonant unit and the secondary-side LC resonant unit perform power transmission through the main-side inductor and the secondary-side inductor, the active rectifier is provided with an active rectifier switch, and the secondary-side phase shift control module is used to adjust the power oscillation elimination data of the active rectifier switch, and control the phase shift outer angle and the inner phase shift angle according to the power oscillation elimination data; wherein, by controlling the phase shift outer angle and the inner phase shift angle, the output power of the system is controlled to meet the power requirement.

2. The system according to claim 1, characterized in that The secondary side phase shift control module comprises: A zero-crossing detection submodule, wherein an input end of the zero-crossing detection submodule is electrically inductively connected to the secondary-side inductor, and is used to generate a zero-crossing detection signal according to a zero-crossing point of the secondary-side resonant current; an oscillation elimination submodule, the input end of the oscillation elimination submodule being electrically connected to the output end of the zero-crossing detection submodule, and being used for performing secondary-side oscillation elimination processing according to the zero-crossing detection signal to obtain the power oscillation elimination data; A dead zone generation submodule, the input end of which is electrically connected to the output end of the oscillation elimination submodule, is used to generate a secondary-side pulse width modulation signal according to the power oscillation elimination data.

3. The system according to claim 2, characterized in that The zero-crossing detection submodule comprises: a first zero-crossing detection circuit, wherein an input end of the first zero-crossing detection circuit is electrically connected between the secondary-side inductor and the secondary-side capacitor, and is used to detect a zero-crossing point of a secondary-side resonant current, and generate a first zero-crossing signal according to the zero-crossing point; wherein the secondary-side resonant current is generated by the secondary-side LC resonant unit; A second zero-crossing detection circuit, wherein the input end of the second zero-crossing detection circuit is electrically connected between the secondary-side inductor and the secondary-side capacitor, and is used for detecting the zero-crossing point of the secondary-side resonant current and generating a second zero-crossing signal according to the zero-crossing point.

4. The system according to claim 2, characterized in that The active rectifier switch includes a first switch, a second switch, a third switch, and a fourth switch. The active rectifier also includes: a first half-bridge on the secondary side and a second half-bridge on the secondary side, wherein the first switch and the second switch are located in the first half-bridge on the secondary side, the third switch and the fourth switch are located in the second half-bridge on the secondary side, the secondary side pulse width modulation signal includes: a first pulse width modulation signal and a second pulse width modulation signal, and the dead zone generation submodule includes: a first dead zone generating circuit, wherein an input end of the first dead zone generating circuit is electrically connected to an output end of the oscillation elimination submodule, and is used to generate the first pulse width modulation signal according to the power oscillation elimination data, so as to perform switch control on the first switch and the second switch according to the first pulse width modulation signal; A second dead zone generating circuit, wherein the input end of the second dead zone generating circuit is electrically connected to the output end of the oscillation elimination submodule, and is used to generate the second pulse width modulation signal according to the power oscillation elimination data, so as to control the switching of the third switch and the fourth switch according to the second pulse width modulation signal.

5. The system according to claim 3 or 4, characterized in that: The oscillation elimination submodule comprises: A synchronous trigger submodule, the input end of which is connected to the output end of the zero-crossing detection submodule, and is used to lock the phase of the secondary-side resonant current to ensure that the zero-crossing detection signal is synchronized with the secondary-side resonant current; A closed-loop control submodule, the input end of which is electrically connected to the output end of the active rectifier, and is used to perform power closed-loop control according to the original output power and the preset target output power to obtain a target internal phase shift angle; wherein the original output power is detected from the output end of the active rectifier, and the target internal phase shift angle is the internal phase shift angle of the active rectifier; A signal processing submodule, wherein the input end of the signal processing submodule is respectively connected to the output end of the synchronization trigger submodule and the output end of the closed-loop control submodule, and the output end of the signal processing submodule is connected to the input end of the dead zone generation submodule, and is used to perform frequency error correction processing according to the target internal phase shift angle, the zero-crossing detection signal, the pre-acquired input power, and the target output power to obtain the power oscillation elimination data.

6. The system according to claim 5, characterized in that The closed-loop control submodule includes: A power acquisition unit, wherein an input end of the power acquisition unit is electrically connected to an output end of the active rectifier, and is used to determine an original output power according to an output signal of the output end of the active rectifier; an error calculation unit, wherein a negative input terminal of the error calculation unit is electrically connected to an output terminal of the power acquisition unit, a positive input terminal of the error calculation unit is input with the target output power, and the error calculation unit is used to determine an output power error according to a difference between the original output power and the target output power to obtain output power error data; A power control unit, wherein the input end of the power control unit is electrically connected to the output end of the error calculation unit, and the output end of the power control unit is electrically connected to the input end of the signal processing submodule, and is used to perform closed-loop power control according to the output power error data to obtain the target internal phase shift angle.

7. An output power control method based on an inductive power transmission system, characterized in that: Applied to the inductive power transmission system according to any one of claims 1 to 6, the method comprises: Acquiring an output signal and a secondary-side resonant current of the inductive power transmission system; Performing zero-crossing detection on the secondary-side resonant current to obtain a zero-crossing detection signal; Calculating power oscillation elimination data according to the zero-crossing detection signal and the output signal; The active rectifier is driven according to the power oscillation elimination data.

8. The method according to claim 7, characterized in that The active rectifier includes: a first switch, a second switch, a third switch and a fourth switch, the power oscillation elimination data includes first delay data and second delay data, and the power oscillation elimination data is calculated according to the zero-crossing detection signal and the output signal to obtain the power oscillation elimination data, including: determining an original output power according to the output signal; Obtaining output power error data according to a difference between the original output power and a preset target output power; Perform power closed-loop control according to the output power error data to adjust the current internal phase shift angle to obtain a target internal phase shift angle; wherein the current internal phase shift angle is the active rectifier internal phase shift angle corresponding to the zero-crossing point of the secondary-side resonant current, and the target output power corresponding to the target internal phase shift angle is the forward output power; Selecting a target external phase shift angle from at least one candidate external phase shift angle according to the target internal phase shift angle, the target output power, and a pre-acquired input power; Calculating the first delay data according to the target external phase shift angle and the zero-crossing detection signal; wherein the first delay data represents the next opening time of the first switch and the second switch; The second delay data is calculated according to the first delay data and the target internal phase shift angle; wherein the second delay data represents the next opening time of the third switch and the fourth switch.

9. The method according to claim 8, characterized in that The selecting a target external phase shift angle from at least one candidate external phase shift angle according to the target internal phase shift angle, the target output power, and the pre-acquired input power comprises: calculating a candidate reactive power according to at least one of the candidate outer phase shift angle, the input power, the target inner phase shift angle and the target output power; Selecting the smallest candidate reactive power from the candidate reactive powers as the target reactive power; The target outer phase shift angle is selected from the candidate outer phase shift angles according to the target inner phase shift angle and the target reactive power.

10. The method according to claim 8, characterized in that The driving the active rectifier according to the power oscillation elimination data comprises: Performing a first dead zone generation process on the first delay data by a first dead zone time generation circuit to obtain a first pulse width modulation signal; wherein the first dead zone generation process is used to set a dead zone time between the first switch and the second switch so that when the first switch is turned on, the second switch will not be turned on; The second delayed data is subjected to a second dead zone generation process by a second dead zone time generation circuit to obtain a second pulse width modulation signal; wherein the second dead zone generation process is used to set a dead zone time between the third switch and the fourth switch so that when the third switch is turned on, the fourth switch will not be turned on; driving the first switch and the second switch to perform switching operations according to the first pulse width modulation signal; The third switch and the fourth switch are driven to perform switching operations according to the second pulse width modulation signal.

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