Self-adaptive full-bridge LCC resonant circuit light load optimization system, method and product

Abstract

The invention relates to an adaptive full-bridge LCC resonant circuit light load optimization system, method and product used in the field of full-bridge LCC resonant converters, the system is connected with a compensation capacitor circuit at the source side of a transformer, the compensation capacitor circuit is composed of a control relay and a compensation capacitor, the control relay is in signal connection with a load circuit, and the compensation capacitor is in signal connection with the load circuit. Switching of a compensation capacitor is controlled based on the load state signal; the method is used for determining parameters of the compensation capacitor circuit and performing switching control on the compensation capacitor circuit based on the real-time power of the load circuit. Switching control of the compensation capacitor circuit can be adaptively realized based on the real-time working condition of the load circuit, and zero-voltage switching of the full-bridge LCC resonance circuit under the light-load working condition is facilitated.

Description

Technical Field

[0001] This application relates to an adaptive full-bridge LCC resonant circuit light-load optimization system, method, and product for the field of full-bridge LCC resonant converters. Background Technology

[0002] The full-bridge LCC resonant converter can utilize the leakage inductance and parasitic capacitance of the high-voltage transformer as resonant elements. It has the advantages of a wide input and output range and soft switching of the full-bridge circuit in the high power range, and has become the mainstream form in the field of high-voltage DC power supply.

[0003] Full-bridge LCC parallel resonant converter circuits need to operate over a wide gain variation range. Under light load conditions, the load power on the transformer secondary side is low, and the energy required to transfer to the resonant cavity on the transformer source side is small, resulting in a significant reduction in the amplitude of the resonant current. This makes it difficult to achieve full discharge of the MOSFETs in the full-bridge circuit within the dead time, making it difficult to maintain zero-voltage turn-on (ZVS). ZVS failure leads to hard switching of the full-bridge circuit. This results in increased MOSFET turn-on losses and higher switching waveform spikes. Furthermore, full-bridge LCC parallel resonant converter circuits typically use RC snubber circuits to absorb switching waveform spikes on the DC bus. However, under hard switching conditions, the RC snubber circuit experiences high thermal stress, which can severely damage circuit components. Although adjusting the device performance parameters and dead time of the resonant circuit can balance the system's conduction losses, efficiency, and the conditions for achieving ZVS, thus contributing to ZVS achievement to some extent, there are limitations in ZVS control due to overall performance requirements. Summary of the Invention

[0004] The purpose of this application is to overcome the shortcomings of the prior art and provide an adaptive full-bridge LCC resonant circuit light-load optimization system, method and product, which can help the full-bridge LCC resonant circuit achieve ZVS under light-load conditions.

[0005] Firstly, this application provides an adaptive full-bridge LCC resonant circuit light-load optimization system, including a full-bridge circuit and an LCC resonant circuit connected to the source side of the transformer, and a load circuit connected to the secondary side of the transformer, specifically adopting the following technical solution: A compensation capacitor circuit is connected to the source side of the transformer. The compensation capacitor circuit consists of a control relay and a compensation capacitor. The control relay is signal-connected to the load circuit and controls the switching of the compensation capacitor based on the load status signal.

[0006] By adopting the above technical solution, the full-bridge LCC resonant circuit can control the switching of the compensation capacitor according to the heavy load and light load conditions. Under the light load condition, the compensation capacitor is switched on and acts as the compensation capacitor in the resonant circuit. Together with the inductor in the resonant circuit, it causes the junction capacitance of the switching transistor in the full-bridge circuit to discharge, so that the full-bridge LCC resonant circuit can achieve ZVS.

[0007] Preferably, the compensation capacitor circuit is connected to the branch output terminal of the LCC resonant circuit.

[0008] Preferably, the source side of the transformer is connected in parallel with several sets of full-bridge circuits and LCC resonant circuits, and the branch output terminal of each LCC resonant circuit is connected to a compensation capacitor circuit.

[0009] By adopting the above technical solution, the compensation capacitor circuit is connected to the output terminal of the full-bridge circuit, and a single full-bridge circuit is used as the control object of the compensation capacitor circuit. When several sets of full-bridge circuits and LCC resonant circuits are connected in parallel to the source side of the transformer to improve the output power, a compensation capacitor circuit is configured for each full-bridge circuit to achieve distributed compensation, achieve precise tuning of each bridge arm, good current sharing effect, strong independence of each branch, and make the ZVS implementation stable and reliable.

[0010] Alternatively, the compensation capacitor circuit is connected to both ends of the source side of the transformer.

[0011] By adopting the above technical solution, the compensation capacitor is connected to the source side trunk of the transformer to provide compensation for all branches, forming a centralized compensation scheme. This simplifies the design and testing of the compensation capacitor circuit parameters, reduces the number of components, simplifies the hardware structure, increases the integration, and results in a small system size and low cost.

[0012] Preferably, the compensation capacitor circuit consists of several control relays and several compensation capacitors. The control relays and compensation capacitors are connected in series to form a capacitor switching control module. All capacitor switching control modules are connected in parallel. Each control relay is connected to the load circuit signal.

[0013] By adopting the above technical solution, and by switching capacitors of different capacities, compensation capacitors that are closest to the ideal value can be provided at different load points, optimizing the ZVS implementation conditions and effectively extending the ZVS range to different load ranges.

[0014] Secondly, this application provides an adaptive full-bridge LCC resonant circuit light-load optimization method, which employs the aforementioned adaptive full-bridge LCC resonant circuit light-load optimization system. The technical solution includes the following steps: S1 connects the compensation capacitor circuit to the source side of the transformer; S2, obtain the rated power of the load circuit, determine whether the load circuit is under light load or heavy load conditions, and send a load status signal. S3, If the load circuit is under heavy load, the control relay of the compensation capacitor circuit enters the cut-out mode based on the load status signal, causing the compensation capacitor to cut out. S4. If the load circuit is under light load, the control relay of the compensation capacitor circuit enters the activation mode based on the load status signal, so that the compensation capacitor is activated.

[0015] By adopting the above technical solution, the cutting off of the compensation capacitor under heavy load conditions does not affect the full-bridge LCC resonant circuit; under light load conditions, the compensation capacitor is put into operation under the timing control of the control relay, causing the switching transistor of the full-bridge circuit to discharge within the dead time, thus enabling the full-bridge circuit to achieve ZVS.

[0016] Preferably, in step S1, before connecting the compensation capacitor circuit to the source side of the transformer, the capacitance value of the compensation capacitor in the compensation capacitor circuit is measured. The specific method is as follows: S101, build a prototype circuit of the full-bridge LCC resonant circuit and make the prototype circuit work under the preset light load conditions. S102 sets the dead time for the switching transistors in the full-bridge circuit and uses an oscilloscope to observe the source-drain voltage waveforms of the switching transistors. S103, connect a variable test capacitor box in parallel with the source side of the transformer, gradually increase the value of the parallel capacitor, and observe the source-drain voltage waveform of the switching transistor after the dead time each time the capacitance value is increased; S104, continuously increase the value of the parallel capacitor until the source-drain voltage of the switching transistor drops to 0V after the dead time; S105, the total capacitance value of the variable test capacitor box measured at this time is used as the capacitance value of the compensation capacitor of the compensation capacitor circuit.

[0017] By adopting the above technical solution, the capacitance value of the compensation capacitor is measured based on the actual needs of light load conditions. This avoids insufficient energy to achieve ZVS due to an excessively small compensation capacitor value, making it difficult to achieve soft switching under light load conditions. At the same time, it avoids excessively large compensation capacitor values, which would cause overvoltage and overcurrent in the resonant circuit, leading to a sharp increase in conduction losses and a decrease in the reliability and efficiency of components.

[0018] Preferably, in S101, the light load condition is a number of light load rated powers of the load circuit, and the capacitance value of a compensation capacitor is measured for each light load rated power. The number of compensation capacitors with measured capacitance values ​​are connected one-to-one with the control relay to form a switching capacitor control module, and all switching capacitor control modules are connected in parallel to the source side of the transformer.

[0019] Preferably, in S2, the real-time power of the load circuit is mapped to the light-load rated power, and the load status signal includes a light-load rated power signal based on the mapped light-load rated power. In S4, the control relay of the compensation capacitor circuit controls the corresponding compensation capacitor to be engaged based on the light-load rated power signal.

[0020] By adopting the above technical solution, flexible capacitor value matching is provided. The controller can determine the required compensation capacitor according to the actual load conditions and achieve step adjustment of the capacitor value from minimum to maximum capacity through different relay combinations.

[0021] Thirdly, the computer program product provided in this application employs a technical solution including a computer program or instructions, which enables the computer program or instructions to implement the steps in the above-mentioned adaptive full-bridge LCC resonant circuit light-load optimization method.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. This application enables the switching transistors of the full-bridge LCC resonant circuit to fully discharge their junction capacitances during the dead time under light load conditions by using a compensation capacitor circuit, thereby satisfying the ZVS condition of the operating transistors. The circuit structure is simple and the control logic is easy to implement.

[0023] 2. This application can adapt to different light load conditions and adaptively control the applied compensation capacitor circuit, realizing dynamic matching of the compensation capacitor, thereby enabling optimization of the ZVS condition of the full-bridge circuit within a wide load range.

[0024] 3. This application can ensure soft switching of the full-bridge LCC resonant circuit under light load conditions, reduce switching transistor losses, and solve the electrothermal stress problem of the RC snubber circuit, reducing the risk of damage to circuit components and improving system life. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a typical full-bridge LCC resonant converter circuit; Figure 2 This is a schematic diagram of a light-load optimization system for an adaptive full-bridge LCC resonant circuit according to an embodiment of this application; Figure 3 This is a schematic diagram of a light-load optimization system for an adaptive full-bridge LCC resonant circuit with two parallel connections according to an embodiment of this application. Figure 4 This is a schematic diagram of another adaptive full-bridge LCC resonant circuit light-load optimization system according to an embodiment of this application; Figure 5 for Figure 4A schematic diagram of the specific circuit structure of the compensation capacitor circuit; Figure 6 The source and drain voltage waveform monitoring diagram of the switching transistor obtained from the simulation test of a light-load optimization system of an adaptive full-bridge LCC resonant circuit with two parallel configurations according to an embodiment of this application. Figure 7 This is a flowchart illustrating an adaptive full-bridge LCC resonant circuit light-load optimization method according to an embodiment of this application. Figure 8 This is a schematic diagram illustrating the process of measuring the capacitance value of the compensation capacitor in an adaptive full-bridge LCC resonant circuit light-load optimization method according to an embodiment of this application. Figure 9 This is a schematic diagram of the architecture of an exemplary computer device according to an embodiment of this application. Detailed Implementation

[0026] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of this application.

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. It should be noted that in the optional embodiments of this application, the object information and other related data involved require the permission or consent of the object when the embodiments of this application are applied to specific products or technologies, and the collection, use, and processing of related data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. That is to say, if the embodiments of this application involve data related to the object, it needs to be obtained with the authorization and consent of the object, the authorization and consent of the relevant departments, and in compliance with the relevant laws, regulations, and standards of the country and region. If personal information is involved in the embodiments, the acquisition of all personal information requires the consent of the individual. If sensitive information is involved, the separate consent of the information subject is required, and the embodiments also need to be implemented with the authorization and consent of the object.

[0028] Please see Figure 1 This is a typical full-bridge LCC resonant converter circuit, including a DC power supply V. dc 1. RC snubber circuit; 2. Full-bridge circuit; 3. LCC resonant circuit; 4. Transformer V CPAnd a load circuit 4 including a rectifier circuit. The RC snubber circuit 1 consists of a resistor R and a capacitor C; the full-bridge circuit 2 consists of switching transistors S11, S12, S13, and S14; the LCC resonant circuit 3 consists of a capacitor Cr1, an inductor Lr1, and a capacitor Cp; the rectifier circuit consists of diodes D5, D6, D7, and D8; and the load circuit 4 also includes a capacitor Co and a resistor Ro. For example, the switching transistors are MOSFETs.

[0029] When the above-mentioned full-bridge LCC resonant converter circuit operates under light load conditions, it can control low gain through phase shifting. At this time, the switching frequency of the system is relatively high and the resonant current is relatively small. It is impossible to fully discharge the junction capacitance of the switching transistor of the full-bridge circuit 2 within the dead time, making it difficult to maintain zero voltage turn-on (ZVS), which leads to hard switching of the MOS transistor when it is turned on.

[0030] To achieve zero-voltage switching (ZVS) of the full-bridge LCC resonant converter circuit under light load conditions, embodiments of this application provide an adaptive full-bridge LCC resonant circuit light-load optimization system. A compensation capacitor circuit 5 is connected to the source side of the transformer. The compensation capacitor circuit consists of a control relay and a compensation capacitor. The control relay is signal-connected to the load circuit and controls the switching of the compensation capacitor based on the load status signal.

[0031] Please see Figure 2 In one specific embodiment of this application, the compensation capacitor circuit is connected to the output terminal of the LCC resonant circuit. This wiring method uses a single full-bridge circuit as the control object of the compensation capacitor circuit. The compensation circuit 5 is connected to the control module 6. When the load circuit is detected to be under light load conditions, the control module 6 controls the compensation capacitor circuit 5 to control the connection of the compensation capacitor, so that the compensation capacitor, as the compensation capacitor in the resonant circuit, together with the inductor in the resonant circuit, causes the junction capacitance of the switching transistor in the full-bridge circuit to discharge, thereby enabling the junction capacitance of the switching transistor in the full-bridge circuit to fully discharge during the dead time, achieving the ZVS condition.

[0032] Please see Figure 3 In another specific embodiment of this application, for the full-bridge LCC resonant converter circuit, several sets of full-bridge circuits and LCC resonant circuits are connected in parallel on the source side of the transformer Vcp to improve the output power. Specifically, in this embodiment, two sets of parallel full-bridge circuits and LCC resonant circuits are used. Correspondingly, the same number of compensation capacitor circuits 5 need to be adapted to perform distributed compensation on the full-bridge circuit. All compensation capacitor circuits 5 are connected to the control module (not shown in the figure).

[0033] The advantages of distributed compensation lie in its ability to independently equip each full-bridge with a compensation capacitor, forming an independent resonant cavity. This allows for precise tuning of each bridge arm, ensuring stable and reliable ZVS under light loads. It effectively suppresses circulating currents caused by minute differences in resonant parameters and provides excellent current sharing. Furthermore, because each branch is relatively independent, single-point faults in the compensation capacitor circuit are less likely to propagate, resulting in high overall system reliability. However, distributed compensation requires the independent design, calculation, and deployment of multiple independent capacitors. The large number of capacitors and the relatively complex drive and control circuits significantly increase the system's size and cost.

[0034] Please see Figure 4 In another specific embodiment of this application, the compensation capacitor circuit is connected to both ends of the transformer source side. This wiring method connects the compensation capacitor circuit to the trunk line of the total output of each full-bridge resonant circuit, providing centralized compensation for each full-bridge circuit.

[0035] While the centralized compensation implementation scheme cannot achieve precise control of branch circuits compared to distributed compensation, it uses a unified compensation capacitor circuit, which makes capacitor parameter design and calculation more convenient, reduces the number of circuit components, simplifies the hardware structure, and can significantly reduce the system size and cost.

[0036] Please see Figure 5 Taking a centralized compensation scheme with two parallel full-bridge LCC circuits as an example, the specific circuit structure of the compensation capacitor circuit is explained. The compensation capacitor circuit consists of several control relays K and several compensation capacitors CPC. The control relays and the compensation capacitors are connected in series to form a capacitor switching control module. All capacitor switching control modules are connected in parallel, and each control relay is connected to the load circuit signal. Typically, the compensation capacitor C... PC The capacitance values ​​range from picofarads (pF) to nanofarads (nF).

[0037] The compensation capacitor circuit, through the switching of different capacitance values, can provide compensation capacitance values ​​closest to the ideal value at different load points, optimizing the ZVS (Zero-Voltage-Free) achievement conditions. Especially for light-load conditions, the use of compensation capacitors with different values ​​adapted to different actual load power can effectively extend the ZVS range to a wider load range, meeting ZVS conditions for lighter loads. This control strategy is relatively simple, easy to implement and debug, and highly reliable.

[0038] Taking a centralized compensation scheme for a full-bridge LCC two-parallel circuit as an example, simulation analysis is performed. When operating under light load conditions, the control relays control the switching off and on of the compensation capacitor C. PC The source-drain voltage Vds1 of the switching transistor under two states was monitored using an oscilloscope, and the simulation results are as follows. Figure 6As shown. Observing the waveform of the source-drain voltage Vds1 of the switching transistor during the dead time of the upper and lower transistors, we can see the cut-out compensation capacitor C. PC The waveform of the source-drain voltage Vds1 of the switching transistor shows that it cannot fully discharge and is in a hard-switching state; while the compensation capacitor C is connected... PC The waveform of the switching transistor shows that the source-drain voltage Vds1 is fully discharged, and at this time the switching transistor is operating in the soft-switching state of ZVS mode.

[0039] Unless otherwise stated, all circuit components (such as switching transistors, diodes, inductors, capacitors, etc.) not explicitly described in the circuit diagrams of this application are connected in the manner commonly used by those skilled in the art to assemble specific circuits. The connection method follows the general specifications of electronic circuit design and does not constitute a limitation on the technical solution of this invention. Specific parameters can be adjusted according to actual application scenarios.

[0040] Please see Figure 7 An adaptive full-bridge LCC resonant circuit light-load optimization method according to an embodiment of this application specifically includes the following steps: S1 connects the compensation capacitor circuit to the source side of the transformer.

[0041] It should be noted that the capacitance value of the compensation capacitor needs to be measured before connecting the compensation capacitor circuit to the source side of the transformer. Please refer to [link / reference needed]. Figure 8 The specific method is as follows: S101, build a prototype circuit of the full-bridge LCC resonant circuit, and let the prototype circuit work under the preset light load conditions.

[0042] S102 sets the dead time for the switching transistors in the full-bridge circuit, and uses an oscilloscope to observe the source-drain voltage waveforms of the switching transistors.

[0043] S103, a variable test capacitor box is connected in parallel to the source side of the transformer. The value of the parallel capacitor is gradually increased. After each increase in the capacitance value, the source-drain voltage waveform of the switching transistor during the dead time is observed.

[0044] S104, continuously increase the value of the parallel capacitor until the source-drain voltage of the switching transistor drops to 0V after the dead time.

[0045] S105, the total capacitance value of the variable test capacitor box measured at this time is used as the capacitance value of the compensation capacitor circuit. In practical applications, in order to ensure that the compensation capacitor has a certain capacitance margin, a standard capacitor with a capacitance value greater than the measured value is usually used as the compensation capacitor after the measurement is completed.

[0046] More specifically, to calculate the capacitance values ​​of the compensation capacitors at different load points separately, the light load conditions were set as several light load rated powers of the load circuit. For each light load rated power, the capacitance value of a compensation capacitor was measured. When calculating the compensation capacitor capacitance values, the highest light load rated power was set as the initial light load condition for the test, at which point the corresponding compensation capacitor capacitance value was the minimum. Then, the light load rated power was gradually decreased, and the compensation capacitor capacitance value was gradually increased until the capacitance values ​​of the compensation capacitors corresponding to all light load rated powers were calculated.

[0047] After calculating the capacitance value of the compensation capacitor, the compensation capacitor is set according to the measurement results. The compensation capacitors are connected one by one to the control relay to form a capacitor switching control module. All capacitor switching control modules are connected in parallel to the source side of the transformer.

[0048] S2 obtains the real-time power of the load circuit, determines whether the load circuit is under light or heavy load conditions, and sends a load status signal.

[0049] More specifically, the power of the load circuit is divided into several power ranges corresponding to the light-load rated power. If the real-time power of the load circuit falls within the power range corresponding to the light-load rated power, it is determined that the real-time power and the light-load rated power form a mapping relationship, and the output load status signal includes the light-load rated power signal corresponding to the mapped light-load rated power.

[0050] S3, if the load circuit is under heavy load, the control relay of the compensation capacitor circuit enters the cut-out mode based on the load status signal, causing the compensation capacitor to cut out.

[0051] S4, if the load circuit is under light load conditions, the control relay of the compensation capacitor circuit enters the activation mode based on the load status signal, causing the compensation capacitor to activate. More specifically, the control relay of the compensation capacitor circuit activates the compensation capacitor whose capacitance value matches the light load rated power based on the light load rated power signal.

[0052] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0053] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the above-described adaptive full-bridge LCC resonant circuit light-load optimization method can be referred to the corresponding process in the aforementioned system embodiments, and will not be repeated here.

[0054] In one embodiment of this application, a computer device is provided, the internal structure of which can be shown in the following diagram. Figure 9 As shown, the computer device includes a processor, memory, network interface, and database connected via a system bus. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The database stores data related to the preset rated power of the load circuit and control strategies based on the real-time power of the load circuit. The network interface communicates with the load power acquisition sensor and the control module of the compensation capacitor circuit. When executed by the processor, the computer program implements an adaptive full-bridge LCC resonant circuit light-load optimization method.

[0055] As used in the above embodiments, depending on the context, the term "when..." can be interpreted as meaning "if...", "after...", "in response to determining...", or "in response to detecting...". Similarly, depending on the context, the phrase "when determining..." or "if (the stated condition or event) is interpreted as meaning "if determining...", "in response to determining...", "when (the stated condition or event) is detected", or "in response to detecting (the stated condition or event)".

[0056] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. An adaptive full-bridge LCC resonant circuit light-load optimization system, comprising a full-bridge circuit and an LCC resonant circuit connected to the source side of a transformer, and a load circuit connected to the secondary side of the transformer, characterized in that: A compensation capacitor circuit is connected to the source side of the transformer. The compensation capacitor circuit consists of a control relay and a compensation capacitor. The control relay is signal-connected to the load circuit and controls the switching of the compensation capacitor based on the load status signal.

2. The adaptive full-bridge LCC resonant circuit light-load optimization system according to claim 1, characterized in that, The compensation capacitor circuit is connected to the output terminal of the LCC resonant circuit.

3. The adaptive full-bridge LCC resonant circuit light-load optimization system according to claim 2, characterized in that, The source side of the transformer is connected in parallel with several sets of full-bridge circuits and LCC resonant circuits, and the output terminal of each branch of the LCC resonant circuit is connected to a compensation capacitor circuit.

4. The adaptive full-bridge LCC resonant circuit light-load optimization system according to claim 1, characterized in that, The compensation capacitor circuit is connected to both ends of the source side of the transformer.

5. An adaptive full-bridge LCC resonant circuit light-load optimization system according to any one of claims 1 to 4, characterized in that, The compensation capacitor circuit consists of several control relays and several compensation capacitors. The control relays and compensation capacitors are connected in series to form a switching capacitor control module. All switching capacitor control modules are connected in parallel. Each control relay is connected to the load circuit signal.

6. An adaptive full-bridge LCC resonant circuit light-load optimization method, employing the adaptive full-bridge LCC resonant circuit light-load optimization system as described in claim 1, characterized in that, Includes the following steps: S1 connects the compensation capacitor circuit to the source side of the transformer; S2, obtain the real-time power of the load circuit, determine whether the load circuit is under light load or heavy load conditions, and send a load status signal. S3, If the load circuit is under heavy load, the control relay of the compensation capacitor circuit enters the cut-out mode based on the load status signal, causing the compensation capacitor to cut out. S4. If the load circuit is under light load, the control relay of the compensation capacitor circuit enters the activation mode based on the load status signal, so that the compensation capacitor is activated.

7. The adaptive full-bridge LCC resonant circuit light-load optimization method according to claim 6, characterized in that, In S1, before connecting the compensation capacitor circuit to the source side of the transformer, the capacitance value of the compensation capacitor in the compensation capacitor circuit is measured. The specific method is as follows: S101, build a prototype circuit of the full-bridge LCC resonant circuit and make the prototype circuit work under the preset light load conditions. S102 sets the dead time for the switching transistors in the full-bridge circuit and uses an oscilloscope to observe the source-drain voltage waveforms of the switching transistors. S103, connect a variable test capacitor box in parallel with the source side of the transformer, gradually increase the value of the parallel capacitor, and observe the source-drain voltage waveform of the switching transistor after the dead time each time the capacitance value is increased; S104, continuously increase the value of the parallel capacitor until the source-drain voltage of the switching transistor drops to 0V after the dead time; S105, the total capacitance value of the variable test capacitor box measured at this time is used as the capacitance value of the compensation capacitor of the compensation capacitor circuit.

8. The adaptive full-bridge LCC resonant circuit light-load optimization method according to claim 7, characterized in that, In S101, the light load condition is a number of light load rated powers of the load circuit. For any one of the light load rated powers, the capacitance value of a compensation capacitor is measured. The number of compensation capacitors with measured capacitance values ​​are connected one-to-one with the control relay to form a switching capacitor control module. All switching capacitor control modules are connected in parallel to the source side of the transformer.

9. The adaptive full-bridge LCC resonant circuit light-load optimization method according to claim 8, characterized in that, In S2, the real-time power of the load circuit is mapped to the light-load rated power. The load status signal includes a light-load rated power signal based on the mapped light-load rated power. In S4, the control relay of the compensation capacitor circuit controls the corresponding compensation capacitor to be engaged based on the light-load rated power signal.

10. A computer program product, characterized in that, The computer program product includes a computer program or instructions that enable the computer program or instructions to perform the steps in the adaptive full-bridge LCC resonant circuit light-load optimization method according to any one of claims 6 to 9.

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