Control circuit and control method for resonant converter, and storage medium

Abstract

Disclosed in the present application are a control circuit and a control method for a resonant converter, and a storage medium. The control circuit comprises: a detection module, which is configured to detect an input signal and an output signal of a resonant converter; a control module, which is configured to determine a target switching frequency, a target intermittent control duty cycle and a target intermittent control period of the resonant converter on the basis of the input signal, the output signal, and a target output voltage of the resonant converter, and generate a first PWM signal, a second PWM signal and a third PWM signal; and a driving module, which is configured to control the intermittent operation of a switching tube in the resonant converter on the basis of the first PWM signal, the second PWM signal and the third PWM signal, such that the output voltage of the resonant converter converges to the target output voltage. The solution of the present application can not only improve the stability of the output voltage of a resonant converter, but can also efficiently and accurately realize the efficiency optimization of the resonant converter under different load conditions.

Description

A control circuit, control method and storage medium for a resonant converter Technical Field

[0001] The present application relates to the field of circuit technology, and in particular to, but not limited to, a control circuit, a control method, and a storage medium for a resonant converter. Background Art

[0002] Resonant converters, with their excellent soft-switching characteristics, have been widely used in renewable energy, electric vehicles, and energy storage systems, becoming a research hotspot in recent years. However, resonant converters suffer from low efficiency under light load conditions.

[0003] In related technologies, fundamental-wave equivalent analysis is often used to calculate the intermittent control duty cycle corresponding to optimal efficiency to optimize the efficiency of resonant converters. Because this method is generally based on a simplified circuit model and ignores higher-order harmonics and nonlinear component characteristics, the intermittent control duty cycle corresponding to the optimal efficiency obtained using this method contains errors, making it impossible to accurately optimize the efficiency of the resonant converter. Summary of the Invention

[0004] The present application provides a control circuit, a control method, and a storage medium for a resonant converter, which can not only improve the stability of the output voltage of the resonant converter, but also efficiently and accurately optimize the efficiency of the resonant converter under different load conditions.

[0005] The technical solution of this application is achieved as follows:

[0006] In a first aspect, the present application provides a control circuit for a resonant converter, the control circuit comprising a resonant converter, a detection module, a control module, and a drive module connected in sequence to form a closed loop;

[0007] The detection module is configured to: detect an input signal and an output signal of the resonant converter;

[0008] The control module is configured to: determine a target switching frequency, a target intermittent control duty cycle, and a target intermittent control period of the resonant converter based on the input signal, the output signal, and a target output voltage of the resonant converter; generate a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; and transmit the first PWM signal, the second PWM signal, and the third PWM signal to the driving module;

[0009] The driving module is configured to control the switching tube in the resonant converter to operate intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0010] In a second aspect, the present application provides a method for controlling a resonant converter, the method comprising:

[0011] detecting an input signal and an output signal of the resonant converter, and converting the input signal and the output signal into an input parameter and an output parameter, respectively;

[0012] determining a target switching frequency of the resonant converter based on the output parameter, the target output voltage of the resonant converter, and a proportional-integral algorithm;

[0013] Determining a target intermittent control duty cycle and a target intermittent control period of the resonant converter based on the input parameter, the output parameter, and the golden jackal algorithm;

[0014] generating a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period;

[0015] Based on the first PWM signal, the second PWM signal, and the third PWM signal, the switching tube in the resonant converter is controlled to operate intermittently, so that the output voltage of the resonant converter converges to the target output voltage.

[0016] In a third aspect, the present application further provides a storage medium having a computer program stored thereon. When the computer program on the storage medium is executed, the control method of the resonant converter provided in the present application is implemented.

[0017] The present application provides a control circuit, control method and storage medium for a resonant converter, wherein the control circuit includes a resonant converter, a detection module, a control module and a drive module connected in sequence to form a closed loop; the detection module is configured to detect an input signal and an output signal of the resonant converter; the control module is configured to determine a target switching frequency, a target intermittent control duty cycle and a target intermittent control period of the resonant converter based on the input signal, the output signal and the target output voltage of the resonant converter; generate a first pulse width modulation (PWM) signal, a second PWM signal and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle and the target intermittent control period; transmit the first PWM signal, the second PWM signal and the third PWM signal to the drive module; the drive module is configured to control the intermittent operation of the switch tube in the resonant converter based on the first PWM signal, the second PWM signal and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0018] In the solution of this application, by adding a control circuit to the resonant converter, it is possible to optimize the efficiency of the resonant converter based on the target switching frequency, target intermittent control duty cycle, and target intermittent control period. By comprehensively considering the impact of factors such as the switching frequency, intermittent control duty cycle, and intermittent control period on the efficiency of the resonant converter, by finding the switching frequency at which the output voltage converges to the target output voltage, and the intermittent control duty cycle and intermittent control period corresponding to the optimal efficiency, not only can the stability of the resonant converter's output voltage be improved, but the efficiency of the resonant converter can also be optimized efficiently and accurately under different load conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG1 is a schematic diagram of a first optional structure of a control circuit of a resonant converter provided in an embodiment of the present application;

[0020] FIG2 is a schematic diagram of an optional structure of a control module provided in an embodiment of the present application;

[0021] FIG3 is a schematic diagram of an optional structure of an algorithm control module provided in an embodiment of the present application;

[0022] FIG4 is a schematic diagram of a first optional structure of a driving module provided in an embodiment of the present application;

[0023] FIG5 is a schematic diagram of a second optional structure of a control circuit of a resonant converter provided in an embodiment of the present application;

[0024] FIG6 is a schematic diagram of a first optional flow chart of a control method for a resonant converter provided in an embodiment of the present application;

[0025] FIG7 is a schematic diagram of a second optional flow chart of a control method for a resonant converter provided in an embodiment of the present application;

[0026] FIG8 is a schematic diagram of a third optional flow chart of the control method of the resonant converter provided in an embodiment of the present application;

[0027] FIG9 is a schematic diagram of a fourth optional flow chart of the control method of the resonant converter provided in an embodiment of the present application;

[0028] FIG10 is a schematic diagram of an optional waveform of operating parameters of a resonant controller provided in an embodiment of the present application;

[0029] FIG11 is a schematic diagram of an optional structural diagram of a topology circuit of a resonant controller provided in an embodiment of the present application;

[0030] FIG12 is a schematic diagram of a third optional structure of a control circuit of a resonant converter provided in an embodiment of the present application;

[0031] FIG13 is a schematic diagram of a second optional structure of a driving module provided in an embodiment of the present application;

[0032] FIG14 is a fifth optional flow chart of the control method of the resonant converter provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the specific technical solutions of the application will be further described in detail below in conjunction with the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application but are not intended to limit the scope of the present application.

[0034] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0035] In the following description, the terms "first, second, and third" are used merely as examples to distinguish between different objects and do not represent a specific order or precedence for the objects. It is understood that the specific order or precedence of "first, second, and third" can be interchanged where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0037] Below, various embodiments of the control circuit, control method, and storage medium of the resonant converter provided in the embodiments of the present application are described.

[0038] In a first aspect, this embodiment provides a control circuit for a resonant converter. Referring to FIG. 1 , the control circuit 10 includes a resonant converter 101 , a detection module 102 , a control module 103 , and a drive module 104 , which are sequentially connected to form a closed loop.

[0039] The detection module 102 is configured to: detect the input signal and the output signal of the resonant converter 101;

[0040] The control module 103 is configured to: determine a target switching frequency, a target intermittent control duty cycle, and a target intermittent control period of the resonant converter based on an input signal, an output signal, and a target output voltage of the resonant converter; generate a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; and transmit the first PWM signal, the second PWM signal, and the third PWM signal to the drive module;

[0041] The driving module 104 is configured to control the switching tube in the resonant converter to operate intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0042] The embodiment of the present application does not specifically limit the connection method between the modules (between the resonant converter 101 and the detection module 102, between the detection module 102 and the control module 103, between the control module 103 and the drive module 104, and between the drive module 104 and the resonant converter 101), and can be configured according to actual conditions.

[0043] Resonant converter 101 is configured to achieve efficient conversion and transmission of electrical energy. This embodiment of the present application does not limit the specific type of resonant converter 101; it can be configured based on practical needs. For example, resonant converter 101 can be a bidirectional CLLC (capacitor-inductor-inductor-capacitor) resonant converter.

[0044] The bidirectional CLLC resonant converter includes a primary inverter, a resonant circuit, and a secondary rectifier. The primary inverter converts the DC input voltage into a square wave, which excites the resonant circuit to generate a sinusoidal signal. The resonant circuit adjusts the sinusoidal signal, and the secondary rectifier rectifies the adjusted sinusoidal signal, which then passes through the output filter capacitor to generate a DC output voltage. The bidirectional CLLC resonant converter has two operating states: When the four power switches of the primary inverter are alternately turned on, the primary inverter operates in a soft switching state, in which power is transferred from the primary to the secondary side, and the bidirectional CLLC resonant converter operates in a charging state. When all four power switches of the primary inverter are turned off, the primary inverter ceases operation, in which power is transferred to the secondary side, and the bidirectional CLLC resonant converter operates in a discharging state.

[0045] The detection module 102 is configured to detect the input signal and the output signal of the resonant converter 101. The embodiment of the present application does not limit the specific structure of the detection module 102, and it can be configured according to actual conditions.

[0046] The embodiments of the present application do not limit the specific content of the input signal and the output signal, and can be configured according to actual conditions. For example, the input signal may include input voltage and input current, and the output signal may include output voltage and output current.

[0047] When the input signal includes input voltage and input current, and the output signal includes output voltage and output current, the detection module may include a voltmeter and an ammeter, and the voltmeter and ammeter are used to detect the input voltage and input current of the input end of the resonant converter, as well as the output voltage and output current of the output end of the resonant converter.

[0048] For the control module 103: it is configured to determine the target switching frequency, target intermittent control duty cycle and target intermittent control period of the resonant converter based on the input signal, the output signal and the target output voltage of the resonant converter; generate a first pulse width modulation PWM signal, a second PWM signal and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle and the target intermittent control period; and transmit the first PWM signal, the second PWM signal and the third PWM signal to the drive module.

[0049] The embodiment of the present application does not limit the specific structure of the control module 103, and it can be configured according to actual conditions.

[0050] Output voltage refers to the voltage output by the resonant converter.

[0051] The target output voltage refers to the voltage setting value that the resonant converter is expected to output.

[0052] Switching frequency refers to the operating frequency of the power switch tube in the resonant converter.

[0053] The target switching frequency refers to the switching frequency when the output voltage of the resonant converter converges to the target output voltage.

[0054] The intermittent control cycle refers to the repeated cycle of turning on and off the topology circuit during the operation of the resonant converter.

[0055] The target intermittent control period refers to the intermittent control period corresponding to the optimized efficiency of the resonant converter.

[0056] The intermittent control duty cycle refers to the proportion of the power-on time of the topology circuit to the total time within an intermittent control cycle.

[0057] The target intermittent control duty cycle refers to the intermittent control duty cycle corresponding to the optimized efficiency of the resonant converter.

[0058] The embodiments of the present application do not limit the specific values ​​of the target output voltage, target switching frequency, target intermittent control duty cycle, and target intermittent control period, and can be configured according to actual conditions.

[0059] The first PWM signal refers to a driving signal for controlling the intermittent operation of the first switching tube and the second switching tube in the resonant converter.

[0060] The second PWM signal refers to a driving signal for controlling the intermittent operation of the third switching tube and the fourth switching tube in the resonant converter.

[0061] For example, when the resonant converter is a CLLC resonant converter, if the direction of power transmission is forward, the first switch tube, the second switch tube, the third switch tube and the fourth switch tube specifically refer to the switch tubes on the primary side of the resonant converter; if the direction of power transmission is reverse, the first switch tube, the second switch tube, the third switch tube and the fourth switch tube specifically refer to the switch tubes on the secondary side of the resonant converter.

[0062] The third PWM signal refers to a PWM signal for implementing an intermittent control duty cycle of the resonant converter.

[0063] The embodiment of the present application does not limit the specific signal content of the first PWM signal, the second PWM signal, and the third PWM signal, which can be configured according to actual conditions.

[0064] For example, the target switching frequency of the resonant converter can be determined based on the input signal and the target output voltage of the resonant converter; the target intermittent control duty cycle and target intermittent control period of the resonant converter can be determined based on the input signal and the output signal. On this basis, a first PWM signal, a drive signal for controlling the intermittent operation of the first and second switching transistors in the resonant converter, and a second PWM signal, a drive signal for controlling the intermittent operation of the third and fourth switching transistors in the resonant converter, can be generated based on the target switching frequency. Both the first PWM signal and the second PWM signal can be square wave signals. A third PWM signal for achieving the intermittent control duty cycle of the resonant converter can be generated based on the target intermittent control duty cycle and the target intermittent control period.

[0065] The driving module 104 is configured to control the switching tube in the resonant converter to operate intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0066] The embodiment of the present application does not limit the specific structure of the driving module 104, and it can be configured according to actual conditions.

[0067] For example, the switch on-off signal obtained after the logic AND operation of the first PWM signal and the third PWM signal can be used to control the intermittent operation of the first switch tube and the second switch tube in the resonant converter; the switch on-off signal obtained after the logic AND operation of the first PWM signal and the third PWM signal can be used to control the intermittent operation of the third switch tube and the fourth switch tube in the resonant converter.

[0068] After controlling the switching tube in the resonant converter to operate intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal, the control circuit determines whether the output voltage of the resonant converter converges to the target output voltage. If not, the detection module, the control module, and the drive module continue to perform their corresponding operations in sequence to continuously adjust the output voltage of the resonant converter. This cycle repeats until the output voltage of the resonant converter converges to the target output voltage.

[0069] An embodiment of the present application provides a control circuit for a resonant converter, the control circuit comprising a resonant converter, a detection module, a control module, and a drive module connected in sequence to form a closed loop; the detection module is configured to detect an input signal and an output signal of the resonant converter; the control module is configured to determine a target switching frequency, a target intermittent control duty cycle, and a target intermittent control period of the resonant converter based on the input signal, the output signal, and a target output voltage of the resonant converter; generate a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; transmit the first PWM signal, the second PWM signal, and the third PWM signal to the drive module; the drive module is configured to control the intermittent operation of the switch tube in the resonant converter based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0070] In the solution of this application, by adding a control circuit to the resonant converter, it is possible to optimize the efficiency of the resonant converter based on the target switching frequency, target intermittent control duty cycle, and target intermittent control period. By comprehensively considering the impact of factors such as the switching frequency, intermittent control duty cycle, and intermittent control period on the efficiency of the resonant converter, by finding the switching frequency at which the output voltage converges to the target output voltage, and the intermittent control duty cycle and intermittent control period corresponding to the optimal efficiency, not only can the stability of the resonant converter's output voltage be improved, but the efficiency of the resonant converter can also be optimized efficiently and accurately under different load conditions.

[0071] Next, the control module 103 in the control circuit 10 of the resonant converter will be described.

[0072] 2 , the control module 103 includes an analog-to-digital conversion module 1031 , an algorithm control module 1032 , and a pulse generation module 1033 , which are connected in sequence.

[0073] The analog-to-digital conversion module 1031 is configured to: convert the received input signal and output signal into input parameters and output parameters respectively;

[0074] The algorithm control module 1032 is configured to: determine the target switching frequency based on the output parameter, the target output voltage, and the proportional-integral algorithm; determine the target intermittent control duty cycle and the target intermittent control period based on the input parameter, the output parameter, and the golden jackal algorithm;

[0075] The pulse generating module 1033 is configured to generate a first PWM signal, a second PWM signal and a third PWM signal based on a target switching frequency, a target intermittent control duty cycle and a target intermittent control period; and transmit the first PWM signal, the second PWM signal and the third PWM signal to the driving module.

[0076] The analog-to-digital conversion module 1031 is configured to convert received input signals and output signals into input parameters and output parameters, respectively. The embodiment of the present application does not limit the specific structure of the analog-to-digital conversion module 1031 and can be configured according to actual conditions.

[0077] The embodiments of this application do not limit the specific content of the input parameters and output parameters, and they can be configured according to actual circumstances. For example, when the input signal (analog signal) includes input voltage and input current, the input parameter (digital signal) also includes input voltage and input current; when the output signal (analog signal) includes output voltage and output current, the output parameter (digital signal) also includes output voltage and output current.

[0078] The analog-to-digital conversion module 1031 may be an analog-to-digital converter, which converts analog quantities into digital quantities to achieve conversion from input signals to input parameters and conversion from output signals to output parameters.

[0079] The algorithm control module 1032 is configured to determine the target switching frequency based on the output parameter, the target output voltage and the first algorithm; and to determine the target intermittent control duty cycle and the target intermittent control period based on the input parameter, the output parameter and the second algorithm.

[0080] The embodiments of the present application do not limit the specific contents of the first algorithm and the second algorithm, and they can be configured according to actual conditions. For example, the first algorithm can be a proportional integral algorithm, and the second algorithm can be a golden jackal algorithm.

[0081] In practice, the first algorithm and the second algorithm may also be other algorithms that can achieve the same function.

[0082] The embodiment of the present application does not limit the specific structure of the algorithm control module 1032, which can be configured according to actual conditions.

[0083] The pulse generating module 1033 is configured to generate a first PWM signal, a second PWM signal and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle and the target intermittent control period; and transmit the first PWM signal, the second PWM signal and the third PWM signal to the driving module.

[0084] The embodiment of the present application does not limit the specific structure of the pulse generating module 1033, and it can be configured according to actual conditions.

[0085] Exemplarily, a first PWM signal and a second PWM signal can be generated respectively based on the target switching frequency, and the first PWM signal and the second PWM signal can be continuous square wave signals with opposite waveforms; a third PWM signal can be generated based on the target intermittent control duty cycle and the target intermittent control period, and the third PWM signal is a signal including a high level and a low level, and the high level duration of the third PWM signal is equal to the product of the target intermittent control duty cycle and the target intermittent control period, and the low level duration is equal to the difference between the target intermittent control period and the high level duration.

[0086] Next, the algorithm control module 1032 in the control module 103 is described.

[0087] Referring to the content shown in FIG3 , the algorithm control module 1032 includes a proportional-integral algorithm module 10321 and a golden jackal algorithm module 10322 .

[0088] When the output parameters include output voltage, the proportional-integral algorithm module 10321 is configured to process the current first output voltage of the resonant converter, the previous second output voltage of the resonant converter, the target output voltage, and the proportional coefficient and integral coefficient of the proportional-integral algorithm to obtain the target switching frequency.

[0089] in:

[0090] The proportional coefficient is used to adjust the output voltage of the resonant converter to offset the error between the output voltage and the target output voltage.

[0091] The integral coefficient is used to accumulate the error between the output voltage and the target output voltage and add it to the output voltage.

[0092] The embodiment of the present application does not limit the specific values ​​of the proportional coefficient and the integral coefficient, and can be configured according to actual conditions.

[0093] Exemplarily, a first error value can be determined based on the current first output voltage and target output voltage of the resonant converter, and a second error value can be determined based on the previous second output voltage and target output voltage of the resonant converter; a first switching frequency can be obtained based on the first error value, the second error value, the proportional coefficient and the integral coefficient; when the resonant converter operates at the first switching frequency, a new first error value continues to be determined based on the current first output voltage and target output voltage of the resonant converter, a new second error value is determined based on the previous second output voltage and target output voltage of the resonant converter, and a new first switching frequency is determined based on the new first error value, the new second error value, the proportional coefficient and the integral coefficient, and this cycle is repeated until the current first output voltage of the resonant converter converges to the target output voltage. At this time, the first switching frequency at the time of convergence is determined as the target switching frequency.

[0094] For example, the first switching frequency can be calculated according to the following formula (1):

[0095] Formula (1);

[0096] Where f is the first switching frequency, kp is the proportional coefficient, ki is the integral coefficient, e t is the first error value, e t-1 is the second error value.

[0097] When the input parameters include input voltage and input current, and the output parameters include output voltage and output current, the golden jackal algorithm module 10322 is configured to: process the input voltage, input current, output voltage, and output current of the resonant converter under each pair of intermittent control parameters in at least two pairs of intermittent control parameters to obtain a target intermittent control duty cycle and a target intermittent control period; the intermittent control parameters include the intermittent control duty cycle and the intermittent control period.

[0098] in:

[0099] The intermittent control duty cycle can be obtained by randomly taking a value within the range of the minimum intermittent control duty cycle and the maximum intermittent control duty cycle; the intermittent control period can be obtained by randomly taking a value within the range of the minimum intermittent control period and the maximum intermittent control period.

[0100] Exemplarily, at least one iteration is performed using the golden jackal algorithm; each iteration includes: based on the input voltage, input current, output voltage, and output current of the resonant converter under each pair of intermittent control parameters in at least two pairs of intermittent control parameters, the efficiency corresponding to each pair of intermittent control parameters can be obtained; the maximum value of the efficiencies corresponding to each pair of intermittent control parameters is determined as a first efficiency; after the iteration is completed, at least one first efficiency can be obtained, and the maximum value of the at least one first efficiency is determined as the optimal efficiency, and the intermittent control parameter corresponding to the optimal efficiency is determined as the target intermittent control parameter, that is, the target intermittent control duty cycle and the target intermittent control period.

[0101] Next, the driving module 104 in the control circuit 10 of the resonant converter will be described.

[0102] 4 , the driving module 104 includes an AND gate module 1041 and a driving submodule 1042 connected in sequence.

[0103] The AND gate module 1041 is configured to: perform an AND operation on the first PWM signal and the third PWM signal to obtain a first target signal; perform an AND operation on the second PWM signal and the third PWM signal to obtain a second target signal; and transmit the first target signal and the second target signal to the driving submodule.

[0104] The embodiment of the present application does not limit the specific structure of the AND gate module 1041, which can be configured according to actual conditions.

[0105] The first target signal refers to a switch on / off signal for controlling the intermittent operation of the first switching tube and the second switching tube in the resonant converter.

[0106] The second target signal refers to a switch on / off signal for controlling the intermittent operation of the third switching tube and the fourth switching tube in the resonant converter.

[0107] The embodiment of the present application does not limit the specific signal content of the first target signal and the second target signal, which can be configured according to actual conditions.

[0108] Exemplarily, the AND gate module 1041 may include four input terminals, the first input terminal and the second input terminal are used to input the first PWM signal and the third PWM signal, respectively, and the third input terminal and the fourth input terminal are used to input the second PWM signal and the third PWM signal, respectively; the AND gate module 1041 may include two output terminals, the first output terminal is used to output the first target signal, and the second output terminal is used to output the second target signal.

[0109] The driving submodule 1042 is configured to: control the first and second switching tubes in the resonant converter to operate intermittently based on the first target signal; and control the third and fourth switching tubes in the resonant converter to operate intermittently based on the second target signal.

[0110] The embodiment of the present application does not limit the specific structure of the driving sub-module 1042, and it can be configured according to actual conditions.

[0111] For example, when the resonant converter is a CLLC resonant converter, if the direction of power transmission is forward, the first switch tube, the second switch tube, the third switch tube and the fourth switch tube specifically refer to the switch tubes on the primary side of the resonant converter; if the direction of power transmission is reverse, the first switch tube, the second switch tube, the third switch tube and the fourth switch tube specifically refer to the switch tubes on the secondary side of the resonant converter.

[0112] The first switch tube, the second switch tube, the third switch tube and the fourth switch tube are alternately turned on, so that the resonant converter operates in a charging state; the first switch tube, the second switch tube, the third switch tube and the fourth switch tube are all turned off, so that the resonant converter operates in a discharging state.

[0113] Exemplarily, when the first target signal is at a high level, the driving submodule controls the first switching tube and the second switching tube in the resonant converter to be turned on, and when the first target signal is at a low level, the driving submodule controls the first switching tube and the second switching tube in the resonant converter to be turned off, thereby realizing intermittent operation of the first switching tube and the second switching tube; correspondingly, when the second target signal is at a high level, the driving submodule controls the third switching tube and the fourth switching tube in the resonant converter to be turned on, and when the second target signal is at a low level, the driving submodule controls the third switching tube and the fourth switching tube in the resonant converter to be turned off, thereby realizing intermittent operation of the third switching tube and the fourth switching tube.

[0114] Next, a power supply method of the control circuit 10 of the resonant converter will be described.

[0115] In a possible implementation, the control circuit 10 of the resonant converter may be powered by the resonant converter 101 .

[0116] In another possible implementation, as shown in FIG5 , the control circuit 10 of the resonant converter may further include a power supply module 105 ; the power supply module 105 is connected to the detection module 102 , the control module 103 , and the drive module 104 , respectively;

[0117] The power module 105 is configured to supply power to the detection module 102 , the control module 103 and the driving module 104 .

[0118] The embodiment of the present application does not limit the specific structure of the power module 105, and it can be configured according to actual conditions.

[0119] In a second aspect, an embodiment of the present application provides a control method for a resonant converter, which is applied to a control circuit of the resonant converter (hereinafter referred to as the control circuit).

[0120] Next, the control method of the resonant converter provided in the embodiment of the present application is described.

[0121] 6 , the control method of the resonant converter may include but is not limited to the following S601 to S605 .

[0122] S601: The control circuit detects the input signal and the output signal of the resonant converter, and converts the input signal and the output signal into an input parameter and an output parameter respectively.

[0123] Exemplarily, S601 may be implemented as follows: the control circuit detects the input signal and the output signal of the resonant converter through the detection module, and converts the input signal and the output signal into input parameters and output parameters respectively through the analog-to-digital conversion module.

[0124] For the specific implementation process of S601, reference may be made to the detailed description of the above-mentioned detection module and analog-to-digital conversion module, which will not be repeated here.

[0125] S602: The control circuit determines a target switching frequency of the resonant converter based on the output parameter, the target output voltage of the resonant converter, and a proportional-integral algorithm.

[0126] Exemplarily, S602 can be implemented as follows: when the output parameters of the control circuit include the output voltage, the control circuit processes the current first output voltage of the resonant converter, the previous second output voltage of the resonant converter, the target output voltage, and the proportional coefficient and integral coefficient of the proportional integral algorithm through the proportional integral algorithm module to obtain the target switching frequency.

[0127] For the specific implementation process of S602, reference may be made to the detailed description of the proportional-integral algorithm module, which will not be repeated here.

[0128] S603: The control circuit determines a target intermittent control duty cycle and a target intermittent control period of the resonant converter based on the input parameter, the output parameter, and the golden jackal algorithm.

[0129] Exemplarily, S603 can be implemented as follows: when the input parameters of the control circuit include input voltage and input current, and the output parameters include output voltage and output current, the control circuit processes the input voltage, input current, output voltage, and output current of the resonant converter under each pair of intermittent control parameters in at least two pairs of intermittent control parameters through the golden jackal algorithm module to obtain the target intermittent control duty cycle and target intermittent control period, wherein the intermittent control parameters are the intermittent control duty cycle and the intermittent control period.

[0130] For the specific implementation process of S603, please refer to the detailed description of the golden jackal algorithm module above, which will not be repeated here.

[0131] S604 : The control circuit generates a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period.

[0132] Exemplarily, S604 may be implemented as follows: the control circuit generates a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal through a pulse generation module based on a target switching frequency, a target intermittent control duty cycle, and a target intermittent control period.

[0133] For the specific implementation process of S604, reference may be made to the detailed description of the pulse generating module above, which will not be repeated here.

[0134] S605: The control circuit controls the switch tube in the resonant converter to operate intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0135] Exemplarily, S605 may be implemented as follows: the control circuit controls the switching tube in the resonant converter to operate intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal through the driving module, so that the output voltage of the resonant converter converges to the target output voltage.

[0136] For the specific implementation process of S605, reference may be made to the detailed description of the above-mentioned driving module, which will not be repeated here.

[0137] An embodiment of the present application provides a control method for a resonant converter, the method comprising: detecting an input signal and an output signal of the resonant converter, and converting the input signal and the output signal into input parameters and output parameters, respectively; determining a target switching frequency of the resonant converter based on the output parameters, the target output voltage of the resonant converter, and a proportional-integral algorithm; determining a target intermittent control duty cycle and a target intermittent control period of the resonant converter based on the input parameters, the output parameters, and a golden jackal algorithm; generating a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; and controlling the intermittent operation of the switching tube in the resonant converter based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

[0138] In the solution of the present application, a proportional-integral algorithm is used to determine the target switching frequency when the output voltage of the resonant converter converges to the target output voltage, and a golden jackal algorithm is used to find the target intermittent control duty cycle and target intermittent control period corresponding to the optimal efficiency. This allows for efficiency optimization of the resonant converter based on the target switching frequency, target intermittent control duty cycle, and target intermittent control period. By comprehensively considering the effects of factors such as the switching frequency, intermittent control duty cycle, and intermittent control period on the efficiency of the resonant converter, by finding the switching frequency when the output voltage converges to the target output voltage, and the intermittent control duty cycle and intermittent control period corresponding to the optimal efficiency, not only can the stability of the resonant converter's output voltage be improved, but the efficiency of the resonant converter under different load conditions can also be optimized efficiently and accurately.

[0139] Next, the process of determining the target intermittent control duty cycle and target intermittent control period of the resonant converter by the control circuit based on the input parameters, the output parameters and the golden jackal algorithm in S603 will be described.

[0140] In the case where the output parameter includes the output voltage, referring to the content shown in FIG. 7 , the process may include but is not limited to the following S701 to S705 .

[0141] S701. The control circuit determines a proportional coefficient and an integral coefficient of the proportional-integral algorithm.

[0142] Exemplarily, the proportional-integral algorithm module of the control circuit pre-stores a proportional coefficient and an integral coefficient of the proportional-integral algorithm. The proportional coefficient and the integral coefficient may be obtained based on empirical values ​​or experimental values, or based on a specific algorithm. Accordingly, S701 may be implemented as follows: the control circuit obtains the proportional coefficient and the integral coefficient of the proportional-integral algorithm from the proportional-integral algorithm module.

[0143] S702. The control circuit determines a first error value based on the current first output voltage of the resonant converter and the target output voltage, and determines a second error value based on the previous second output voltage of the resonant converter and the target output voltage.

[0144] Exemplarily, S702 may be implemented as follows: the control circuit determines the difference between the current first output voltage of the resonant converter and the target output voltage as the first error value; and determines the difference between the previous second output voltage of the resonant converter and the target output voltage as the second error value.

[0145] S703: The control circuit determines a first switching frequency based on the first error value, the second error value, the proportional coefficient, and the integral coefficient, so that the resonant converter outputs a first adjustment voltage when operating at the first switching frequency.

[0146] Exemplarily, S703 can be implemented as follows: the control circuit performs a subtraction on the first error value and the second error value to obtain a first difference; multiplies the first error value by the proportional coefficient to obtain a first product; multiplies the first difference by the integral coefficient to obtain a second product; determines the sum of the first product and the second product as the first switching frequency; the control circuit controls the resonant converter to operate at the first switching frequency; and the resonant converter outputs a first adjustment voltage when operating at the first switching frequency.

[0147] S704 : When the first adjustment voltage converges to the target output voltage, the control circuit determines the first switching frequency as the target switching frequency.

[0148] Exemplarily, S704 may be implemented as follows: the control circuit determines whether the first adjustment voltage converges to the target output voltage; and when the first adjustment voltage converges to the target output voltage, determines the first switching frequency as the target switching frequency.

[0149] S705. When the first adjustment voltage does not converge to the target output voltage, the control circuit re-executes the steps of determining the first error value based on the current first output voltage of the resonant converter and the target output voltage, and determining the second error value based on the previous second output voltage of the resonant converter and the target output voltage, until the first adjustment voltage converges to the target output voltage, and determines the first switching frequency when the first adjustment voltage converges to the target output voltage as the target switching frequency.

[0150] Exemplarily, S705 can be implemented as follows: the control circuit determines whether the first adjustment voltage converges to the target output voltage; if the first adjustment voltage does not converge to the target output voltage, re-execute S702 to S705 until the first adjustment voltage converges to the target output voltage; and determine the first switching frequency when the first adjustment voltage converges to the target output voltage as the target switching frequency.

[0151] Next, the process of determining the target switching frequency of the resonant converter based on the output parameter, the target output voltage of the resonant converter, and the proportional-integral algorithm in S602 will be described.

[0152] In the case where the input parameters include input voltage and input current, and the output parameters include output voltage and output current, referring to the content shown in FIG. 8 , the process may include but is not limited to the following S801 to S804 .

[0153] S801. The control circuit determines the maximum number of iterations M and the maximum number of iterations N of the golden jackal algorithm.

[0154] Both M and N are integers greater than 1.

[0155] The embodiment of the present application does not limit the specific values ​​of the maximum number of iterations M and the maximum number of iterations N of the golden jackal algorithm, which can be configured according to actual conditions.

[0156] Exemplarily, the Golden Jackal algorithm module of the control circuit pre-stores the maximum number of iterations M and N of the Golden Jackal algorithm. The maximum number of iterations M and N can be obtained based on empirical or experimental values, or based on a specific algorithm. Accordingly, S801 can be implemented as follows: the control circuit obtains the maximum number of iterations M and N of the Golden Jackal algorithm from the Golden Jackal algorithm module.

[0157] S802 : The control circuit performs the i-th iteration to obtain the i-th target conversion efficiency.

[0158] The i-th iteration includes: determining N pairs of intermittent control parameters; determining the conversion efficiency corresponding to each pair of intermittent control parameters based on the input voltage, input current, output voltage, and output current of the resonant converter under each pair of the N pairs of intermittent control parameters, to obtain N first conversion efficiencies; and determining the maximum value of the N first conversion efficiencies as the i-th target conversion efficiency.

[0159] The initial value of i is 1, and i is a positive integer less than or equal to M.

[0160] The intermittent control parameters include an intermittent control duty cycle and an intermittent control period.

[0161] The intermittent control duty cycle can be obtained by randomly taking a value within the range of the minimum intermittent control duty cycle and the maximum intermittent control duty cycle; the intermittent control period can be obtained by randomly taking a value within the range of the minimum intermittent control period and the maximum intermittent control period.

[0162] The first conversion efficiency refers to the ratio of the output power to the input power of the resonant converter, where the output power is equal to the product of the output voltage and the output current, and the input power is equal to the product of the input voltage and the input current.

[0163] Exemplarily, S802 may be implemented as follows: the control circuit performs an i-th iteration to obtain an i-th target conversion efficiency. The i-th iteration includes: obtaining N pairs of intermittent control parameters by randomly selecting values ​​within the range of a minimum intermittent control duty cycle and a maximum intermittent control duty cycle, and randomly selecting values ​​within the range of a minimum intermittent control period and a maximum intermittent control period; traversing the N pairs of intermittent control parameters, and for each pair of intermittent control parameters, determining the conversion efficiency corresponding to the pair of intermittent control parameters based on the input voltage, input current, output voltage, and output current of the resonant converter under the pair of intermittent control parameters to obtain a first conversion efficiency. After the traversal is completed, N first conversion efficiencies are obtained; and determining the maximum value of the N first conversion efficiencies as the i-th target conversion efficiency.

[0164] In practice, during the first iteration, N pairs of intermittent control parameters corresponding to the first iteration can be obtained by randomly selecting values ​​within the range of the minimum intermittent control duty cycle and the maximum intermittent control duty cycle, as well as randomly selecting values ​​within the range of the minimum intermittent control period and the maximum intermittent control period; during the i-th iteration (i is greater than 1 and less than or equal to M), N pairs of intermittent control parameters corresponding to the i-th iteration can be obtained through the i-1-th iteration of the golden jackal algorithm.

[0165] S803 , the control circuit increases the value of i by 1 and then re-executes the i-th iteration until the value of i is greater than M, thereby obtaining M target conversion efficiencies.

[0166] Exemplarily, S803 may be implemented as follows: the control circuit increases i by 1, and then re-executes step S802 , and repeats this cycle until i is greater than M; after the execution is completed, M target conversion efficiencies are obtained.

[0167] S804 : The control circuit determines the intermittent control duty ratio and the intermittent control period corresponding to the maximum value among the M target conversion efficiencies as the target intermittent control duty ratio and the target intermittent control period.

[0168] Exemplarily, S804 may be implemented as follows: the control circuit determines a maximum value among the M target conversion efficiencies; and determines the intermittent control duty ratio and intermittent control period corresponding to the maximum value as the target intermittent control duty ratio and target intermittent control period.

[0169] The control method of the resonant converter provided in the embodiment of the present application may further include a process in which the output voltage of the resonant converter converges to the changed target output voltage.

[0170] In the case where the target output voltage changes, referring to the content shown in FIG. 9 , the process may include but is not limited to the following S901 to S902 .

[0171] S901 : The control circuit obtains the changed target output voltage.

[0172] For example, assuming that the set target output voltage has changed and is different from the original target output voltage, correspondingly, S901 may be implemented as: the control circuit obtains the changed target output voltage.

[0173] S902: The control circuit uses the changed target output voltage as a new target output voltage and re-executes the detection of the input signal and the output signal of the resonant converter until the output voltage of the resonant converter converges to the changed target output voltage.

[0174] Exemplarily, S902 may be implemented as follows: the control circuit uses the changed target output voltage as a new target output voltage and re-executes S701 to S705 until the output voltage of the resonant converter converges to the changed target output voltage.

[0175] The control circuit of the resonant converter provided in this application is described below through a detailed embodiment.

[0176] Currently, isolated bidirectional direct current to direct current (DC / DC) converters are widely used in fields such as renewable energy, electric vehicles, and energy storage systems. Bidirectional CLLC resonant converters, with their excellent soft-switching characteristics and high efficiency and power density, have become highly favored among isolated DC / DC converters and have become a research hotspot in recent years. However, the resonant circuit of a bidirectional CLLC resonant converter suffers from low efficiency under light load conditions. Furthermore, the actual parameter values ​​of the components in the resonant circuit often differ from their nominal parameter values. Therefore, an adaptive control algorithm is needed that can not only obtain high-precision control parameters for optimal efficiency under all load conditions of the resonant circuit, but also eliminate the impact of the error between the actual and nominal parameter values ​​of the components on the control parameters, thereby obtaining the optimal control parameters.

[0177] In addition, dynamic response is also an important indicator for evaluating the control algorithm of the resonant converter. The complex control algorithm makes it take a long time for the controller to calculate the optimal intermittent control duty cycle and intermittent control period when the load changes. During this period, the switching loss generated by the resonant converter is large and the conversion efficiency is low. Therefore, it is necessary to reduce the intermittent control duty cycle d (equivalent to the above intermittent control duty cycle) and the intermittent control period T. m The calculation time (equivalent to the above-mentioned intermittent control period) is also an important optimization direction for improving the conversion efficiency of the resonant converter.

[0178] In related technologies, the calculation formula of the intermittent control duty cycle d corresponding to the optimal efficiency is generally derived by the fundamental equivalent analysis method, and the intermittent control period T is roughly taken as m This solution has two disadvantages. First, since the fundamental wave analysis method is usually based on a simplified circuit model and ignores the characteristics of high-order harmonics and nonlinear components, it cannot accurately reflect the actual performance of the circuit. Therefore, the intermittent control duty cycle d corresponding to the calculated optimal efficiency has errors. Second, the intermittent control period T m Choosing too large or too small will reduce the efficiency. Roughly selecting an intermittent control cycle is not equivalent to selecting the intermittent control cycle corresponding to the optimal efficiency.

[0179] Next, the operating principle of the bidirectional CLLC resonant converter is described.

[0180] As shown in Figure 10, T is the duty cycle of the primary inverter of the bidirectional CLLC resonant converter, T m is the intermittent control period, d is the intermittent control duty cycle, and the intermittent control waveforms 1001 and 1002 are the working voltage U of the primary inverter respectively. ab , working current I R1The intermittent control waveforms 1003 and 1004 are the working voltage U of the secondary inverter respectively. cd , working current I R2 The output voltage waveform 1005 is the output voltage U of the bidirectional CLLC resonant converter. o Waveform diagram.

[0181] FIG11 is an optional topology circuit diagram of a bidirectional CLLC resonant converter provided in an embodiment of the present application. As shown in FIG11 , the primary side of the bidirectional CLLC resonant converter 110 includes: a power supply U in , power switches Q1~Q4; the resonant circuit of the bidirectional CLLC resonant converter 110 includes inductor L1, inductor L2, inductor L m , capacitor C1, capacitor C2; the secondary side of the bidirectional CLLC resonant converter 110 includes power switches Q5~Q8, capacitor C o 、Load R L The bidirectional CLLC resonant converter 110 has two working states: m In the stage, power switches Q1, Q4, Q2 and Q3 are turned on alternately, U ab Advance I R1 The primary inverter works in the soft switching state. At this time, the electric energy is transferred from the primary side of the resonant converter to the secondary side. The rectifier is connected to the output filter capacitor C o Charging, while the load R L Power supply, output voltage U o Continue to rise; in dT m ~T m In this stage, the power switch tubes Q1~Q4 are all turned off, the primary side inverter no longer works, and the power is transmitted to the secondary side. At this time, the output filter capacitor C o Discharging to load R L Provide electrical energy, output voltage U o Continue to decline.

[0182] The embodiment of the present application provides a control system for optimizing the efficiency of a bidirectional CLLC resonant converter based on the golden jackal algorithm (hereinafter referred to as the control system). As shown in FIG12 , the control system 120 is composed of a CLLC resonant topology circuit 1201 (equivalent to the above-mentioned resonant converter), a measurement circuit 1202 (equivalent to the above-mentioned detection module), a drive circuit 1203 (equivalent to the above-mentioned drive module), an auxiliary power supply circuit 1204 (equivalent to the above-mentioned power supply module), and a control circuit 1205 (equivalent to the above-mentioned control module) with an embedded microcontroller as the core. When the load changes, the output voltage is maintained stable by changing the operating frequency of the primary inverter, and the golden jackal algorithm is used to optimize the intermittent control duty cycle d and the intermittent control period T. m To improve the working efficiency of the resonant converter.

[0183] The auxiliary power supply circuit 1204 provides a stable operating voltage V for other circuits except the CLLC resonant topology circuit 1201. low Measuring circuit 1202, the measured input voltage V of the CLLC resonant converter in 、Input current I in , output voltage V o , output current I o The output is sent to the control circuit 1205 with the embedded microcontroller as the core; the control circuit 1205 with the embedded microcontroller as the core outputs the control signal to the drive circuit 1203 after calculation; the drive circuit 1203 controls the opening and closing of the four switch tubes Q1~Q4 of the primary side inverter and the four switch tubes Q5~Q8 of the secondary side according to the control signal.

[0184] As shown in Figure 12, the control circuit 1205, which is based on an embedded microcontroller, includes an analog-to-digital (A / D) conversion module 12051 (equivalent to the aforementioned A / D conversion module), a variable frequency proportional integral (PI) control module 12052 (equivalent to the aforementioned PI algorithm module), a Golden Jackal algorithm intermittent control module 12053 (equivalent to the aforementioned Golden Jackal algorithm module), and a pulse width modulation generation module 12054 (equivalent to the aforementioned pulse generation module). The input signal of the A / D conversion module 12051 is the output signal of the measurement circuit 1202. The A / D conversion module 12051 converts the converted output voltage V o The signal is output to the variable frequency PI control module 12052, which converts the converted input voltage V in 、Input current I in , output voltage V o , output current I o The frequency signal (equivalent to the target switching frequency) output by the variable frequency PI control module 12052 and the intermittent control duty cycle d signal (equivalent to the target intermittent control duty cycle) corresponding to the optimal efficiency output by the intermittent control module 12053 of the golden jackal algorithm are output, and the switching period T m The signals (equivalent to the target intermittent control period) are respectively output to the pulse width modulation generation module 12054, and the output signals PWM1, PWM2, and PWM3 (equivalent to the first PWM signal, the second PWM signal, and the third PWM signal) of the pulse width modulation generation module 12054 are output to the driving circuit 1203.

[0185] As shown in Figure 13, driver circuit 1203 includes an AND gate module 12031 (equivalent to the aforementioned AND gate module) and a driver module 12032 (equivalent to the aforementioned driver submodule). AND gate module 12031 includes a power supply VCC, resistors R1 and R2, and diodes D1 through D4. The output signal of pulse width modulation generation module 12054 serves as the input signal to AND gate module 12031. After processing by AND gate module 12031, the output signal is fed to driver module 12032 to control the intermittent operation of the resonant converter's switches.

[0186] The specific logic flow with the embedded microcontroller as the core is shown in FIG14 , including S1401 to S1407 .

[0187] S1401, start.

[0188] S1402. Configure the peripheral parameters of the control circuit. First, configure the peripheral parameters related to the control circuit with the embedded microcontroller as the core, including the operating modes of the A / D conversion module, interrupts, and timer-related peripherals. Among them, the timer 1 interrupt is used to execute the operation process of the variable frequency PI control module, output the frequency signal and feed it back to the pulse width modulation generation module. The pulse width modulation generation module generates the corresponding PWM signal based on the frequency signal output by the variable frequency PI control module; the timer 2 interrupt is used to execute the operation process of the Golden Jackal algorithm intermittent control module, outputting the intermittent control duty cycle d signal corresponding to the optimal efficiency and the switching period T m signal to optimize the efficiency of the resonant converter; Timer 3 is used by the pulse width modulation generation module, and the intermittent control duty cycle d signal and the switching period T corresponding to the optimal efficiency output by the intermittent control module of the golden jackal algorithm are used. m signal, generates the corresponding PWM signal; configures the A / D conversion module to work in Direct Memory Access (DMA) mode.

[0189] S1403, initialize the parameters of the variable frequency PI control module. Initialize the relevant parameters of the variable frequency PI control module according to the system preset values, including the target output voltage value V out 、The current actual output voltage V o The target output voltage V out The error value e t , the actual output voltage before the last adjustment V o and the target output voltage V out The error value e t-1 , the proportional coefficient kp multiplied by the error value, the integral coefficient ki multiplied by the accumulated amount of the error value, etc., and the initial value of the intermittent control duty cycle d is set to 1, the intermittent control period T mThe initial value of is set to 5ms. The frequency value fs (equivalent to the target switching frequency) can be calculated by the variable frequency PI control module.

[0190] S1404, initialize the parameters of the intermittent control module of the golden jackal algorithm. The relevant parameters include the number of individuals in the population N, the individual dimension Dim, the maximum number of iterations T, the population iteration count value t, the number of individuals in the population count value n, the upper limit d of the intermittent control duty cycle d max , lower bound d min , intermittent control period T m The upper bound T mmax , lower bound T mmin The specific values ​​of the above parameters can be set based on experience or experimental values, or based on a specific algorithm. For example, you can set N to 30, Dim to 2, T to 50 times, d max 0.8, d min 0.1, T mmax 5ms, T mmin The initial value of t is 1 and the initial value of n is 1.

[0191] S1405: Adjust the switching frequency through the variable frequency PI control module. The variable frequency PI control module uses the interrupt of timer 1 to perform its calculation process and adjusts the frequency of the pulse width modulation generation module based on the obtained frequency value fs.

[0192] S1406, determine whether the load of the resonant converter has changed, if so, execute S1407, if not, continue to execute S1406. The measurement circuit is used to detect in real time whether the load of the resonant converter has changed, that is, the actual output voltage value V o Multiply by the actual output current value I o The obtained output power is checked to see if it changes. If the load does not change, the load is monitored again in the next intermittent control cycle to see if it changes.

[0193] S1407, determine whether the output voltage of the resonant converter is stable, if so, execute S1408, if not, continue to execute S1407. The actual output voltage V of the resonant converter is detected in real time by the measuring circuit. o Is it stable, that is, the actual output voltage V o Whether the target output voltage V is reached out If so, the intermittent control module of the golden jackal algorithm is used for iterative calculation.

[0194] S1408. Determine whether t is greater than the maximum number of iterations T. If so, execute S1409; if not, continue to execute S1414.

[0195] S1409. Determine whether n is greater than the number of individuals in the population N. If so, execute S1410; if not, continue to execute S1412.

[0196] S1410, calculate the fitness of the nth individual in the tth generation. Determine the position coordinate Y of the nth individual in the tth generation population n (The horizontal axis is the intermittent control duty cycle d n , the vertical axis is the intermittent control period T mn ), the fitness of the nth individual in the tth generation is the efficiency of the resonant converter at the position coordinates of the nth individual in the tth generation. Specifically, the efficiency corresponding to the switching frequency can be obtained by dividing the output power of the resonant converter at the position coordinates of the nth individual in the tth generation by the input power. This efficiency is used as the fitness of the nth individual in the tth generation. The output power is equal to the actual output voltage value V o Multiply by the actual output current value I o The input power is equal to the input voltage value V i Multiply by the input current value I i The product of .

[0197] The position coordinates of N individuals corresponding to the first iteration can be calculated using the following formula (2):

[0198] Formula (2);

[0199] Among them, Y is the position coordinate, the horizontal axis is the intermittent control duty cycle d, and the vertical axis is the intermittent control period T m .

[0200] By using the above formula (2) to calculate N times, the position coordinates of N individuals can be obtained. When calculating the intermittent control duty cycle d of the horizontal coordinate, Ymax is d max 、Ymin is d min ; In the calculation of the vertical coordinate intermittent control period T m When Ymax is T mmax 、Ymin is T mmin .

[0201] At the tth iteration (t is greater than 1 and less than or equal to the maximum number of iterations T), the position coordinates of the N individuals corresponding to the tth iteration can be obtained through the t-1th iteration of the golden jackal algorithm. See S1412 for detailed description.

[0202] S1411, increase n by 1, and return to execute S1409 until n is greater than the number of individuals in the population N. After the execution is completed, N efficiencies can be obtained, and the maximum value of the N efficiencies is used as the fitness corresponding to the t-th iteration.

[0203] S1412, update the position coordinates of the t-th generation individual, and increase t by 1, return to execute S1408, until t is greater than the maximum number of iterations T. After the t-th iteration, compare the fitness corresponding to the t-th iteration with the fitness corresponding to the t-1-th iteration, and retain the larger fitness. After the entire iterative process is completed, the maximum fitness can be obtained. The intermittent control duty cycle d and intermittent control period T corresponding to the maximum fitness are m , which is the intermittent control duty cycle d and intermittent control period Tm corresponding to the optimal efficiency.

[0204] The updated position coordinates of the t-th generation individual are calculated using the following formulas (3) to (9), specifically: finding the Y with the highest fitness in the t-th iteration M (t) and the second highest Y FM (t) The position coordinates of the individual, for each individual in the t-th iteration process, calculate the individual's Levy motion random number LF n (t) and escape energy E n (t), use the following formula (3) to formula (9) to calculate the new position Y of the individual n (t+1), the new intermittent control duty cycle d and intermittent control period T can be obtained. m .

[0205] Formula (3);

[0206] Where μ and v are random numbers in the range of (0, 1), and beta is a default constant of 1.5. σ is given by the following formula (4):

[0207] Formula (4);

[0208] Among them, beta is a default constant, which is 1.5.

[0209] Formula (5);

[0210] Where r is a random number in the range of (0, 1), c1 is a constant of 1.5, t is the current number of iterations, and T is the maximum number of iterations.

[0211] Formula (6);

[0212] Where rl represents a random number based on Levy distribution.

[0213] Formula (7);

[0214] Among them, Prey(t) is the position coordinate of the iterated individual, and Y1(t) is the updated position coordinate of the individual with the highest fitness.

[0215] Formula (8);

[0216] Among them, Prey(t) is the position coordinate of the iterated individual, and Y2(t) is the updated position coordinate of the individual with the second highest fitness.

[0217] Formula (9);

[0218] S1413, determine the intermittent control parameters corresponding to the optimal efficiency. After the entire iterative process is completed, the position coordinates of the individual with the highest fitness, that is, the highest efficiency, among all individuals in the population can be obtained, that is, the intermittent control duty cycle d and intermittent control period T corresponding to the optimal efficiency. m , which is used as the intermittent control duty cycle and intermittent control period when the resonant converter achieves the optimal efficiency under the current load conditions.

[0219] S1414, end.

[0220] The beneficial effects of the present application include: 1. The golden jackal algorithm is used to optimize efficiency, which optimizes the intermittent control duty cycle d and intermittent control period T caused by the inability of simplified mathematical models to accurately describe complex system characteristics and component parameter errors. m There is an error, and the optimal efficiency point can be found; 2. PI variable frequency control is used to adjust the switching frequency of the resonant converter to stabilize the output voltage, with fast dynamic response and stable output voltage; 3. The control circuit is simple, reliable, and low-cost, and does not require the complex control of a dedicated integrated circuit. It can be seen that this solution can obtain the intermittent control duty cycle d and intermittent control period T corresponding to the optimal efficiency of the CLLC resonant converter under different loads without the need to derive complex mathematical models and complex calculations through the intelligent optimization algorithm, namely the golden jackal algorithm. m .

[0221] In a third aspect, the present application further provides a storage medium having a computer program stored thereon. When the computer program on the storage medium is executed, any one of the control methods for the resonant converter provided in the embodiments of the present application is implemented.

[0222] It should be noted that the description of the above storage medium and device embodiments is similar to the description of the above method embodiments and has similar beneficial effects as the method embodiments. For technical details not disclosed in the storage medium and device embodiments of this application, please refer to the description of the method embodiments of this application for understanding.

[0223] It should be understood that “one embodiment” or “an embodiment” mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, “in one embodiment” or “in some embodiments” appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean 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 the present application. The above-mentioned serial numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments.

[0224] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0225] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0226] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0227] In addition, all functional units in the embodiments of the present application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the above-mentioned integrated units can be implemented in the form of hardware or in the form of hardware plus software functional units.

[0228] Those skilled in the art will understand that all or part of the steps of the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, and other media that can store program codes.

[0229] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0230] The above is merely an embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A control circuit for a resonant converter, characterized in that, The control circuit includes a resonant converter, a detection module, a control module, and a drive module that are connected in sequence to form a closed loop; The detection module is configured to: detect the input signal and the output signal of the resonant converter; The control module is configured to: determine the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period of the resonant converter based on the input signal, the output signal, and the target output voltage of the resonant converter; generate a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; and transmit the first PWM signal, the second PWM signal, and the third PWM signal to the drive module; The drive module is configured to: control the switching tube in the resonant converter to work intermittently based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

2. The control circuit according to claim 1, characterized in that The control module includes an analog-to-digital conversion module, an algorithm control module, and a pulse generation module that are connected in sequence; The analog-to-digital conversion module is configured to: convert the received input signal and output signal into input parameters and output parameters respectively; The algorithm control module is configured to: determine the target switching frequency based on the output parameter, the target output voltage, and the proportional-integral algorithm; determine the target intermittent control duty cycle and the target intermittent control period based on the input parameter, the output parameter, and the golden jackal algorithm; The pulse generation module is configured to: generate the first PWM signal, the second PWM signal, and the third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; and transmit the first PWM signal, the second PWM signal, and the third PWM signal to the drive module.

3. The control circuit according to claim 2, wherein The algorithm control module includes a proportional-integral algorithm module and a golden jackal algorithm module; When the output parameter includes the output voltage, the proportional-integral algorithm module is configured to: process the current first output voltage of the resonant converter, the previous second output voltage of the resonant converter, the target output voltage, and the proportional coefficient and integral coefficient of the proportional-integral algorithm to obtain the target switching frequency; When the input parameter includes the input voltage and input current, and the output parameter includes the output voltage and output current, the golden jackal algorithm module is configured to: process the input voltage, input current, output voltage, and output current of the resonant converter under each pair of intermittent control parameters in at least two pairs of intermittent control parameters to obtain the target intermittent control duty cycle and the target intermittent control period; the intermittent control parameters include the intermittent control duty cycle and the intermittent control period.

4. The control circuit according to claim 1, characterized in that, The drive module includes an AND gate module and a drive sub-module; The AND gate module is configured to perform an AND operation on the first PWM signal and the third PWM signal to obtain a first target signal; perform an AND operation on the second PWM signal and the third PWM signal to obtain a second target signal; and transmit the first target signal and the second target signal to the drive sub-module; The drive sub-module is configured to intermittently control the first switch tube and the second switch tube in the resonant converter based on the first target signal; and intermittently control the third switch tube and the fourth switch tube in the resonant converter based on the second target signal.

5. The control circuit according to claim 1, wherein The control circuit further includes a power supply module; the power supply module is respectively connected to the detection module, the control module, and the drive module; The power supply module is configured to supply power to the detection module, the control module, and the drive module.

6. A control method for a resonant converter, characterized in that, The method includes: Detecting an input signal and an output signal of the resonant converter, and respectively converting the input signal and the output signal into input parameters and output parameters; Determining a target switching frequency of the resonant converter based on the output parameters, a target output voltage of the resonant converter, and a proportional-integral algorithm; Determining a target intermittent control duty cycle and a target intermittent control period of the resonant converter based on the input parameters, the output parameters, and a golden jackal algorithm; Generating a first pulse width modulation (PWM) signal, a second PWM signal, and a third PWM signal based on the target switching frequency, the target intermittent control duty cycle, and the target intermittent control period; Controlling the switching tubes in the resonant converter to intermittently operate based on the first PWM signal, the second PWM signal, and the third PWM signal, so that the output voltage of the resonant converter converges to the target output voltage.

7. The control method according to claim 6, wherein When the output parameters include an output voltage, the determining the target switching frequency of the resonant converter based on the output parameters, the target output voltage of the resonant converter, and a proportional-integral algorithm includes: Determining a proportional coefficient and an integral coefficient of the proportional-integral algorithm; Determining a first error value based on a current first output voltage of the resonant converter and the target output voltage, and determining a second error value based on a previous second output voltage of the resonant converter and the target output voltage; Determining a first switching frequency based on the first error value, the second error value, the proportional coefficient, and the integral coefficient, so that the resonant converter outputs a first adjusted voltage when operating at the first switching frequency; When the first adjusted voltage converges to the target output voltage, determining the first switching frequency as the target switching frequency; In the case where the first regulated voltage does not converge to the target output voltage, re - execute the steps of determining the first error value based on the current first output voltage and the target output voltage of the resonant converter, and determining the second error value based on the previous second output voltage and the target output voltage of the resonant converter, until the first regulated voltage converges to the target output voltage, and then determine the first switching frequency when the first regulated voltage converges to the target output voltage as the target switching frequency.

8. The control method according to claim 6, characterized in that In the case where the input parameters include the input voltage and the input current, and the output parameters include the output voltage and the output current, determining the target intermittent control duty cycle and the target intermittent control period of the resonant converter based on the input parameters, the output parameters, and the golden jackal algorithm includes: Determine the maximum number of iterations M and the maximum number of iterations N of the golden jackal algorithm; Execute the i - th iteration to obtain the i - th target conversion efficiency; the i - th iteration includes: determining N pairs of intermittent control parameters; the intermittent control parameters include the intermittent control duty cycle and the intermittent control period; based on the input voltage, input current, output voltage, and output current of the resonant converter under each pair of the N pairs of intermittent control parameters, determine the conversion efficiency corresponding to each pair of the intermittent control parameters to obtain N first conversion efficiencies; determine the maximum value among the N first conversion efficiencies as the i - th target conversion efficiency; After increasing i by 1, re - execute the i - th iteration until i is greater than M to obtain M target conversion efficiencies; Determine the intermittent control duty cycle and the intermittent control period corresponding to the maximum value among the M target conversion efficiencies as the target intermittent control duty cycle and the target intermittent control period; Wherein, both M and N are integers greater than 1; the initial value of i is 1, and i is a positive integer less than or equal to M.

9. The control method according to claim 6, characterized in that In the case where the target output voltage changes, the method further includes: Obtain the changed target output voltage; Take the changed target output voltage as the new target output voltage, and re - execute the steps of detecting the input signal and the output signal of the resonant converter until the output voltage of the resonant converter converges to the changed target output voltage.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method according to any one of claims 6 to 9.

Images