Control method and computer device compatible with battery load and constant current load

Abstract

The present invention relates to the technical field of resonant circuits, and discloses a control method and computer device compatible with battery loads and constant current loads. The method uses the output voltage of a voltage loop to obtain a limiting factor to limit the output current amplitude of a current loop, and at the same time, further adjusts the output current of the current loop through a current feedforward value, thereby avoiding a large current caused by a voltage rise, and avoiding a voltage drop when entering a constant current loop. At this time, the output voltage and the modulated second output current are compared, and a curve fitting is performed after taking the smaller one, so that the LLC circuit can achieve control of the output frequency value. By introducing an output that can be used for the voltage loop in the voltage loop and the current loop of the LLC circuit to limit the limiting factor of the current loop, and adding a current feedforward in the current loop, it is ensured that the LLC circuit can achieve effective control of the output frequency value under different load conditions, and is compatible with switching between different output loads.

Description

Technical Field

[0001] The present invention relates to the technical field of resonant circuits, and in particular to a control method and computer equipment that are compatible with a battery load and a constant current load. Background Art

[0002] Since the LLC circuit (resonant circuit) has functions such as constant voltage, constant current, and constant power, and has the advantages of small ripple and high efficiency, it is often used in power electronic equipment, especially in application scenarios such as charging piles, HVDC, chargers, and high-precision DC sources. In power electronic equipment, LLC circuits are generally used for isolation and buck-boost circuits. In this way, high-frequency isolation can replace the power frequency isolation transformer, and the voltage ratio can be adjusted to achieve buck-boost. Therefore, LLC circuits have become the current trend of technological development. In the traditional control loop of the LLC part, there are mainly voltage loops and current loops. The voltage loop is used to achieve the function of constant voltage, and the current is used for constant current control. Battery loads and constant current loads are commonly used loads for LLC output. When the LLC circuit switches to connect the load, the prior art often affects the normal operation of the circuit because it is not compatible with the battery load and constant current load. Summary of the invention

[0003] Based on this, it is necessary to provide a control method and computer device that are compatible with battery loads and constant current loads to address the problem that the prior art is not compatible with battery loads and constant current loads when the LLC circuit switches to connect the load.

[0004] A control method compatible with battery load and constant current load, the method comprises the following steps: obtaining the output voltage of a voltage loop in an LLC circuit, and obtaining a limiting factor based on the output voltage; using the limiting factor as the current output upper limit of a current loop in the LLC circuit to limit the output current of the current loop; obtaining a first output current before modulation of the current loop in the LLC circuit, and obtaining a current feedforward value based on the first output current; obtaining a second output current based on the difference between a PI-adjusted output value and a current feedforward value of a difference between a set current value and the first output current, wherein the PI-adjusted output value includes an output value of the difference between the set current value and the first output current after P adjustment plus an output value of the difference between the set current value and the first output current after I adjustment; comparing the output voltage with the second output current, and performing curve fitting based on the smaller of the two values ​​to obtain a control frequency value.

[0005] The above control method compatible with battery load and constant current load uses the output voltage of the voltage loop to obtain the limiting factor to limit the output current amplitude of the current loop, and at the same time, the output current of the current loop is further adjusted by the current feedforward value to avoid the voltage rise and cause a large current, and avoid the voltage drop when entering the constant current loop. At this time, the output voltage and the modulated second output current are compared, and the smaller one is taken and curve fitting is performed to enable the LLC circuit to control the output frequency value. By introducing an output that can be used for the voltage loop in the voltage loop and current loop of the LLC circuit to limit the limiting factor of the current loop, and adding a current feedforward method to the current loop, it is ensured that the LLC circuit can effectively control the output frequency value under different load conditions, and is compatible with switching between different output loads.

[0006] In one embodiment, obtaining the limiting factor based on the output voltage includes: substituting the output voltage into a limiting factor calculation formula to obtain the limiting factor; the limiting factor calculation formula is:

[0007] I UpLimit =RemVout*k+b; where I UpLimit is the limiting factor, RemVout is the output voltage of the voltage loop, k is the multiple of the output voltage, and b is the initial value of the current limiting.

[0008] In one embodiment, the value range of k is 1 to 1.5, and the value range of b is 0 to 0.5.

[0009] In one embodiment, obtaining a current feedforward value based on the first output current includes: substituting the first output current into a current feedforward value calculation formula to obtain the current feedforward value; the current feedforward value calculation formula is:

[0010] I Forward =Iout*p; where I Forward is the current feedforward value, Iout is the output current, and p is the regulation coefficient.

[0011] In one embodiment, I Forward The value range is 0 to 0.2.

[0012] In one embodiment, the control method for compatible battery load and constant current load further includes adjusting the values ​​of k, b and p according to the output load connected to the LLC circuit.

[0013] In one of the embodiments, the output load connected to the LLC circuit includes a battery load or a constant current load.

[0014] In one embodiment, when the output load connected to the LLC circuit is a battery load, the method for adjusting the values ​​of k, b, and p includes setting p to a first preset value, and gradually adjusting k and b from small to large until the upper limit values ​​of k and b are obtained when p is the first preset value; gradually increasing the value of the first preset value, and at the same time gradually adjusting and testing the upper limit values ​​of k and b until the LLC circuit switches the output load to a battery load, and the second output current of the current loop is less than the output voltage of the voltage loop within a preset time due to the modulation effect of the limiting factor and the current feedforward value on the current loop, and the current loop controls the output frequency value of the LLC circuit.

[0015] In one embodiment, when the output load connected to the LLC circuit is a constant current load, the method for adjusting the values ​​of k, b, and p includes setting p to a second preset value, and gradually adjusting k and b from large to small until the lower limit values ​​of k and b are obtained when p is the second preset value; gradually reducing the value of the second preset value, and at the same time gradually adjusting and testing the lower limit values ​​of k and b until the LLC circuit switches the output load to a constant current load. Because the limiting factor is affected by the output voltage, the value of the current loop cannot be reduced to less than the output voltage of the voltage loop, and the voltage loop controls the output frequency value of the LLC circuit.

[0016] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and wherein the processor implements the steps of the method described in any one of the above embodiments when executing the computer program. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A method flow chart of a method for controlling a compatible battery load and a constant current load according to one embodiment of the present invention;

[0019] Figure 2 A flowchart of the specific steps of a control method for a compatible battery load and a constant current load according to one embodiment of the present invention;

[0020] Figure 3 A method flow chart of a method for adjusting the values ​​of k, b, and p when the output load is a battery load according to one embodiment of the present invention;

[0021] Figure 4 A method flow chart of a method for adjusting the values ​​of k, b, and p when the output load is a constant current load according to one embodiment of the present invention;

[0022] Figure 5 A waveform diagram of an LLC circuit according to one embodiment of the present invention when the connected load is suddenly switched to a battery load;

[0023] Figure 6 It is a waveform diagram of an LLC circuit according to one embodiment of the present invention when the connected load is suddenly switched to a constant current load. DETAILED DESCRIPTION

[0024] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0025] 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 in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0026] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0027] LLC circuit is a circuit often used in power electronic equipment, especially in charging piles, HVDC, chargers, and high-precision DC sources. LLC circuit has the functions of constant voltage, constant current, and constant power, and has the characteristics of small ripple and high efficiency. It is generally used as an isolation and buck-boost circuit in the system. In this way, high-frequency isolation replaces the power frequency isolation transformer, and the voltage ratio can also be adjusted to achieve buck-boost. Therefore, LLC circuit has become the trend of current technological development.

[0028] The present invention provides a control method compatible with battery load and constant current load, which can ensure that an LLC circuit can switch between the battery load and the constant current load at will. Figure 1This is a flow chart of a method for controlling a compatible battery load and a constant current load according to one embodiment of the present invention. The method includes the following steps S100 to S500.

[0029] S100: Obtain an output voltage of a voltage loop in an LLC circuit, and obtain a limiting factor based on the output voltage.

[0030] S200: Using the limiting factor as the current output upper limit of the current loop in the LLC circuit to limit the output current of the current loop.

[0031] S300: Acquire a first output current before current loop modulation in an LLC circuit, and acquire a current feedforward value based on the first output current.

[0032] S400: A second output current is obtained based on the difference between the PI-regulated output value of the difference between the set current value and the first output current and the current feed-forward value, wherein the PI-regulated output value includes the output value of the difference between the set current value and the first output current after P-regulation plus the output value of the difference between the set current value and the first output current after I-regulation.

[0033] S500: Compare the output voltage with the second output current, and perform curve fitting based on the smaller value of the two to obtain a control frequency value.

[0034] Figure 2 The following is a flowchart of the specific steps of a control method for compatible battery load and constant current load in one embodiment of the present invention. The control loop of the LLC circuit mainly includes a voltage loop and a current loop. The voltage loop is used to realize the function of constant voltage control, and the current loop is used for the function of constant current control. After the output of the two loops is minimized, the existing LLC circuit goes through a curve fitting link and finally outputs a frequency value. This frequency value is used to realize PWM output, thereby achieving the control purpose. Figure 2In the control method provided by the present invention, a limiting factor and a current feedforward value are added to the control loop of the LLC circuit to adjust the relationship between the current loop and the voltage loop. When adding the limiting factor, it is first necessary to obtain the output voltage of the voltage loop output, and obtain the limiting factor for the current loop according to the output voltage. The limiting factor is used as the upper limit value of the current output of the current loop to limit the output current of the current loop, that is, the output of the voltage loop is used to limit the amplitude of the current loop integral. At the same time, when adding the current feedforward value, it is necessary to obtain the first output current of the current loop after modulation, and obtain the current feedforward value of the current loop according to the first output current. The current feedforward value is fed back to the current loop, and the second output current of the current loop after modulation is the difference between the PI adjustment output value of the difference between the set current value and the first output current and the current feedforward value, that is, the output current of the current loop is used to limit the output amplitude of the current loop.

[0035] By reasonably adjusting the limiting factor and the current feedforward value, it can be achieved that when switching the battery load, the integral upper limit of the current loop is affected by the output of the voltage loop and is limited; at the same time, the impact current during load switching is very large, so the current feedforward value will also be very large, and the final output of the current loop minus the feedforward value will become smaller and smaller, and the output value of the current loop will soon be less than the output value of the voltage loop, and take over the control loop to avoid voltage rise causing large current. When the constant current load is applied, the current feedforward value plays a major role. Since the integral amplitude of the current loop is limited by the output of the voltage loop, the current feedforward value is small, and the output value of the current loop is large, so the LLC circuit will always work in the voltage loop to avoid entering the current loop and causing voltage drop. By adjusting the relationship between the voltage loop and the current loop of the LLC circuit with the control method provided by the present invention, it can be ensured that the battery load and the constant current load can be switched at will.

[0036] In one embodiment, obtaining the clipping factor based on the output voltage includes substituting the output voltage into a clipping factor calculation formula to obtain the clipping factor. The clipping factor calculation formula is:

[0037] I UpLimit =RemVout*k+b;

[0038] Among them, I UpLimit is the limiting factor, RemVout is the output voltage of the voltage loop, k is the multiple of the output voltage, and b is the initial value of the current limiting.

[0039] After obtaining the output voltage of the voltage loop, it is necessary to substitute the output voltage into the calculation formula of the limiting factor to obtain the limiting factor. The output voltage of the voltage loop is RemVout, where the value range of RemVout is 0 to 1. After substituting into the calculation formula of the limiting factor, the limiting factor I is obtained. UpLimit , using the clipping factor I UpLimit The value of is used as the integral output upper limit of the current loop to limit the output current amplitude of the current loop. The k value in the calculation formula of the limiting factor is a multiple of the output voltage of the voltage loop, which is used to adjust the speed of limiting; the b value is the initial value of the limiting factor, which has a direct effect on the current starting value of the current loop.

[0040] In one embodiment, the value range of k is 1 to 1.5, and the value range of b is 0 to 0.5. It can be seen from the value range of k that the limiting factor is positively correlated with the output voltage of the voltage loop. Therefore, when the value of the output voltage is larger, the value of the limiting factor is larger, the restriction on the integral output of the current loop is larger, and the amplitude of the output current of the current loop is smaller; similarly, when the value of the output voltage is smaller, the value of the limiting factor is smaller, the restriction on the integral output of the current loop is smaller, and the amplitude of the output current of the current loop is larger.

[0041] In one embodiment, obtaining the current feedforward value based on the first output current includes substituting the first output current into a feedforward current calculation formula to obtain the current feedforward value. The feedforward current calculation formula is:

[0042] I Forward =Iout*p;

[0043] Among them, I Forward is the current feedforward value, Iout is the output current, and p is the regulation coefficient.

[0044] After obtaining the first output current of the current loop, it is necessary to substitute the first output current into the calculation formula of the current feedforward value to obtain the current feedforward value. The output current of the current loop is Iout, and after substituting it into the calculation formula of the current feedforward value, the current feedforward value Iout is obtained. Forward . The current feedforward value I ForwardThe value of is fed back to the current loop, and the output current amplitude of the current loop can also be limited. The current feedforward value can adjust the output current of the current loop when a large impact current appears in the LLC circuit, so that it is easier to enter the current loop and prevent the impact current from causing a sharp increase in the current at the output end of the current loop and triggering overcurrent protection to cause the device to shut down. At the same time, the current feedforward value can also be more conducive to entering the voltage loop when the current is smooth.

[0045] In one embodiment, I Forward The value range is 0~0.2. Forward The value of can be adjusted according to different usage requirements. Forward is obtained by multiplying the output current of the current loop by the coefficient p. Forward The value range of is related to the size of the p value. When a better balancing effect on the impact current is required, the p value needs to be larger; and when the LLC circuit needs to enter the voltage loop more smoothly, the p value needs to be reduced as much as possible.

[0046] In one embodiment, the control method for compatible battery load and constant current load further includes adjusting the values ​​of k, b and p according to the output load connected to the LLC circuit. Since the requirements of battery load and constant current load are contradictory, one needs to make the LLC circuit quickly enter the current loop after connection, and the other needs to make the LLC circuit quickly enter the voltage loop after connection, it is necessary to continuously adjust the values ​​of k, b, and p through multiple tests to realize the LLC circuit to switch the battery load and constant current load at will.

[0047] In one embodiment, the output load connected to the LLC circuit includes a battery load or a constant current load. Battery load and constant current load are commonly used loads for LLC output. When carrying a battery load, the controller needs to quickly enter the current loop to control the charging current constant current operation. Since the integral of the current loop is already positively saturated when the battery load is switched, even if there will be a large impact current when the load is switched, it still takes a certain amount of time for the current loop to exit saturation. Before the current loop is desaturated, the voltage loop still works, and the voltage loop will raise the output voltage. In this raising process, the output current will surge, thereby triggering the overcurrent protection and causing shutdown. After using the control method provided by the present invention, the output of the voltage loop is used to calculate the limiting factor to limit the integral upper limit of the current loop, so as to limit the output amplitude of the current loop; at the same time, the current feedforward value can prevent the output end of the current loop from suddenly increasing and causing overcurrent protection. When the output current of the current loop is large, the current feedforward value also increases accordingly, and the output current of the current loop can be adjusted in time, so that the output of the current loop becomes smaller and smaller, and will soon be less than the output value of the voltage loop, so that the LLC circuit enters the current loop and controls the output current value.

[0048] When carrying a constant current load, the controller needs to quickly enter the voltage loop to stabilize the output voltage, but the output current at this time will quickly increase to the constant current value set by the load, so the integral of the current loop needs to be a relatively large initial value, or it needs to be in a positive saturation state to enable the controller to quickly enter the voltage loop. If the current loop is entered at this time, the output voltage will be uncontrollable, causing a relatively deep voltage drop, which does not meet the requirements of the drop amplitude. After using the control method provided by the present invention, since the limiting factor used to limit the upper limit of the integral of the current loop is related to the output voltage of the voltage loop, the existence of the limiting factor is not conducive to the rapid increase of the output of the current loop; at the same time, the output current of the current loop can be relatively smooth when it is switched to a constant current load. At this time, the size of the p value does not play a major role in the final output of the current loop, so that the LLC circuit always works in the voltage loop to avoid entering the current loop and causing voltage drop. The relationship between the current loop and the voltage loop is determined by combining the roles of the limiting factor and the current feedforward value in the circuit, thereby achieving the goal of arbitrarily switching the LLC circuit between the battery load and the constant current load.

[0049] Figure 3 This is a method flow chart of a method for adjusting the values ​​of k, b, and p when the output load is a battery load according to one embodiment of the present invention. In one embodiment, when the output load connected to the LLC circuit is a battery load, the method for adjusting the values ​​of k, b, and p includes the following steps S610 to S620.

[0050] S610: Set p to a first preset value, and gradually adjust k and b from small to large until upper limits of k and b are obtained when p is the first preset value.

[0051] S620: gradually increase the value of the first preset value, and at the same time gradually adjust and test the upper limit values ​​of k and b until the LLC circuit switches the output load to a battery load, and the second output current of the current loop is less than the output voltage of the voltage loop within a preset time due to the modulation effect of the limiting factor and the current feedforward value on the current loop, and the current loop controls the output frequency value of the LLC circuit.

[0052] In this experiment, the values ​​of k, b, and p are tested when the LLC circuit is switched to the battery load. When switched to the battery load, it is hoped that the values ​​of k and b are smaller and the value of p is larger. Therefore, during the experiment, the value of p is first set to the first preset value with a smaller value, and the values ​​of k and b are changed from small to large. The regulating effect of the limiting factor and the current feedforward value in the circuit is tested at this time, and the upper limit values ​​of k and b are obtained by continuous adjustment. Then the first preset value of p is increased, and the values ​​of k and b are changed from small to large. The regulating effect of the limiting factor and the current feedforward value in the circuit is tested at this time, and the upper limit values ​​of k and b are re-determined. The above steps are repeated several times until the limiting factor and the current feed-forward value can better adjust the current loop, so that when the LLC circuit is switched to the battery load, the second output current of the current loop can be adjusted to be less than the output voltage of the voltage loop in a shorter time, so that the LLC circuit determines the output frequency value according to the output circuit of the current loop, that is, the current loop becomes a control circuit.

[0053] Figure 4 The method flow chart of the method for adjusting the values ​​of k, b, and p when the output load is a constant current load according to one embodiment of the present invention. In one embodiment, when the output load connected to the LLC circuit is a constant current load, the method for adjusting the values ​​of k, b, and p includes the following steps S630 to S640.

[0054] S630: Set p to the second preset value, and gradually adjust k and b from large to small until the lower limit values ​​of k and b are obtained when p is the second preset value.

[0055] S640: gradually reduce the value of the second preset value, and at the same time gradually adjust and test the lower limit values ​​of k and b until the LLC circuit switches the output load to a constant current load, and the value of the current loop cannot be reduced to a value less than the output voltage of the voltage loop because the limiting factor is affected by the output voltage, and the voltage loop controls the output frequency value of the LLC circuit.

[0056] In this experiment, the values ​​of k, b, and p are tested when the LLC circuit is switched to the constant current load. When switching to the constant current load, it is hoped that the values ​​of k and b are larger and the value of p is smaller. Therefore, in the experiment, the value of p is first set to a second preset value with a larger value, and the values ​​of k and b are changed from large to small, and the regulating effect of the limiting factor and the current feedforward value in the circuit at this time is tested, and the lower limit values ​​of k and b are continuously adjusted until the lower limit values ​​of k and b are obtained. Then the second preset value of p is adjusted to a smaller value, and the values ​​of k and b are changed from large to small, and the regulating effect of the limiting factor and the current feedforward value in the circuit at this time is tested, and the lower limit values ​​of k and b are re-determined. The above steps are repeated several times until the limiting factor and the current feedforward value can make the second output current of the current loop unable to adjust to an output voltage less than the constant current load when the LLC circuit is switched to the battery load, so that the LLC circuit determines the output frequency value according to the output circuit of the voltage loop, that is, the current loop becomes a control circuit.

[0057] In one embodiment, after the above experimental test, the values ​​of k, b, and p are determined to be k=1.18, b=0.22, and p=0.19. Figure 5 This is a waveform diagram of when the connected load of the LLC circuit of one embodiment of the present invention is suddenly switched to the battery load. It can be seen that after the relationship between the current loop and the voltage loop in the LLC circuit is adjusted by the control method provided by the present invention, when the battery voltage is 240V and the battery current is 100A, it can be seen that when the battery load is switched, a large impact current will be generated in the circuit, and the output voltage of the LLC circuit is pulled to the battery port voltage. Then the current loop takes over the control circuit, and the LLC circuit quickly enters the current loop and controls the output current to maintain the circuit in a constant current working state of 100A. Figure 6 This is a waveform diagram when the connected load of the LLC circuit of one embodiment of the present invention is suddenly switched to a constant current load. It can be seen that after the control method provided by the present invention adjusts the relationship between the current loop and the voltage loop in the LLC circuit, the operating current of the constant current load is set at 90A. When the LLC circuit is connected to the constant current load, the current in the circuit is relatively smooth, the LLC circuit quickly stabilizes the current, and the voltage in the circuit tends to be stable after a small drop.

[0058] It should be understood that although Figure 1 , Figure 3-4 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 , Figure 3-4 At least part of the steps may include multiple steps or multiple stages. These steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed in turn or alternately with other steps or at least part of the steps or stages in other steps.

[0059] The present invention also provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and wherein the processor implements the steps of the method described in any one of the above embodiments when executing the computer program.

[0060] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0061] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0062] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0063] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A control method compatible with battery load and constant current load, characterized in that: include: Obtaining an output voltage of a voltage loop in an LLC circuit, and obtaining a limiting factor based on the output voltage; The limiting factor is used as the current output upper limit of the current loop in the LLC circuit to limit the output current of the current loop, and the limiting object of the limiting factor is the amplitude of the current loop integral regulation branch; Acquire a first output current before current loop modulation in the LLC circuit, and acquire a current feedforward value based on the first output current; The second output current is obtained based on the difference between the PI adjustment output value of the difference between the set current value and the first output current and the current feedforward value, wherein the PI adjustment output value includes the output value of the difference between the set current value and the first output current after P adjustment plus the output value of the difference between the set current value and the first output current after I adjustment; The output voltage is compared with the second output current, and a curve fitting is performed based on the smaller value of the two to obtain a control frequency value.

2. The control method for compatible battery load and constant current load according to claim 1, characterized in that: Obtaining the clipping factor based on the output voltage includes: substituting the output voltage into a clipping factor calculation formula to obtain the clipping factor; the clipping factor calculation formula is: ； Among them, I UpLimit is the limiting factor, RemVout is the output voltage of the voltage loop, k is the multiple of the output voltage, and b is the initial value of the current limiting.

3. The control method for compatible battery load and constant current load according to claim 2, characterized in that: The value range of k is 1~1.5, and the value range of b is 0~0.

5.

4. The control method for compatible battery load and constant current load according to claim 3, characterized in that: Acquiring a current feedforward value based on the first output current includes: substituting the first output current into a calculation formula of a current feedforward value to acquire the current feedforward value; the calculation formula of the current feedforward value is: ； Among them, I Forward is the current feedforward value, Iout is the first output current, and p is the regulation coefficient.

5. The control method for compatible battery load and constant current load according to claim 4, characterized in that: The control method for compatible battery load and constant current load also includes: The values ​​of k, b and p are adjusted according to the output load to which the LLC circuit is connected.

6. The control method for compatible battery load and constant current load according to claim 5, characterized in that: The output load connected to the LLC circuit includes a battery load or a constant current load.

7. The control method for compatible battery load and constant current load according to claim 6, characterized in that: When the output load connected to the LLC circuit is a battery load, the method for adjusting the values ​​of k, b, and p includes: Set p to a first preset value, and gradually adjust k and b from small to large until the upper limit values ​​of k and b are obtained when p is the first preset value; The value of the first preset value is gradually increased, and the upper limit values ​​of k and b are gradually adjusted and tested at the same time, until the LLC circuit switches the output load to the battery load, and the second output current of the current loop is less than the output voltage of the voltage loop within a preset time due to the modulation effect of the limiting factor and the current feed-forward value on the current loop, and the current loop controls the output frequency value of the LLC circuit.

8. The control method for compatible battery load and constant current load according to claim 6, characterized in that: When the output load connected to the LLC circuit is a constant current load, the method for adjusting the values ​​of k, b, and p includes: Set p to the second preset value, and gradually adjust k and b from large to small until the lower limit values ​​of k and b are obtained when p is the second preset value; The value of the second preset value is gradually reduced, and the lower limit values ​​of k and b are gradually adjusted and tested at the same time, until the LLC circuit switches the output load to a constant current load, and the value of the current loop cannot be reduced to a value less than the output voltage of the voltage loop because the limiting factor is affected by the output voltage, and the voltage loop controls the output frequency value of the LLC circuit.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

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