Feedforward control circuit, feedforward control method, device, medium and product

Abstract

The present invention provides a feedforward control circuit, a feedforward control method, a device, a medium, and a product, which are applied to the field of power conversion technology. In the feedforward control circuit, the first input terminal and the second input terminal of the control circuit are respectively connected to the input terminal and the output terminal of the four-tube buck-boost converter, and are used to determine the current working mode of the four-tube buck-boost converter according to the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter, and output a corresponding pulse width modulation signal based on the current working mode; the two input terminals of the half-bridge drive circuit are respectively connected to the two output terminals of the control circuit, and the four output terminals of the half-bridge drive circuit are connected to the four control terminals of the four-tube buck-boost converter, and are used to generate a corresponding drive signal according to the pulse width modulation signal. The present invention outputs corresponding pulse width modulation signals for different working modes of the four-tube buck-boost converter to offset the influence of input voltage disturbance on the output voltage.

Description

Technical Field

[0001] The present invention relates to the field of power conversion technology, and in particular to a feedforward control circuit, a feedforward control method, a device, a medium and a product. Background Art

[0002] Four-tube buck-boost converters are often used in storage servers to charge battery modules. The battery modules are used to temporarily back up the system when the alternating current (AC) power is lost, and to write cache to the hard disk, thus ensuring that system data is not lost. Figure 1 As shown, a conventional four-transistor buck-boost converter has three operating modes: when the output voltage sampling value VOUT is less than the input voltage sampling value VIN, the circuit operates in the buck mode (buck), MOS transistors Q11 and Q12 are alternately turned on, MOS transistor Q13 is always turned on, and MOS transistor Q14 is always turned off; when the output voltage sampling value VOUT is close to the input voltage sampling value VIN, the circuit operates in the buck-boost mode (buck), MOS transistors Q11 and Q12 are alternately turned on in the first half of a cycle, and MOS transistors Q13 and Q14 are alternately turned on in the second half; when the output voltage sampling value VOUT is greater than the input voltage sampling value VIN, the circuit operates in the boost mode (boost), MOS transistors Q13 and Q14 are alternately turned on, MOS transistor Q11 is always turned on, and MOS transistor Q12 is always turned off.

[0003] When the input voltage fluctuates, the conventional buck circuit's voltage feedforward control method can offset the impact of input voltage fluctuations on the output voltage by compensating for the pulse width modulation (PWM) duty cycle. However, since the four-tube buck-boost converter has three operating modes, the conventional buck circuit's voltage feedforward control method is no longer suitable. Therefore, the feedforward control design must be tailored to the four-tube buck-boost converter's different operating modes.

[0004] It can be seen that how to find a feedforward control circuit suitable for a four-tube buck-boost converter in different operating modes is a problem that those skilled in the art need to solve. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a feedforward control circuit, feedforward control method, device, medium and product, which can solve the problem that the voltage feedforward control method of a conventional buck circuit is no longer suitable for the feedforward control of a four-tube buck-boost converter with three operating modes.

[0006] To solve the above technical problems, on the one hand, an embodiment of the present invention provides a feedforward control circuit, comprising: a control circuit and a half-bridge drive circuit;

[0007] The first input terminal and the second input terminal of the control circuit are respectively connected to the input terminal and the output terminal of the four-tube buck-boost converter, and are used to determine the current operating mode of the four-tube buck-boost converter according to the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter, and output a corresponding pulse width modulation signal based on the current operating mode;

[0008] The first input terminal and the second input terminal of the half-bridge drive circuit are respectively connected to the first output terminal and the second output terminal of the control circuit, and the four output terminals of the half-bridge drive circuit are respectively connected to the four control terminals of the four-tube buck-boost converter, so as to generate corresponding drive signals according to the pulse width modulation signal to control the four-tube buck-boost converter.

[0009] In some embodiments, the control circuit includes: a first analog-to-digital converter, a second analog-to-digital converter, a single-chip microcontroller, a first modulation circuit, and a second modulation circuit;

[0010] The input end of the first analog-to-digital converter is connected to the input end of the four-tube buck-boost converter as the first input end of the control circuit, and the output end of the first analog-to-digital converter is connected to the first input end of the single-chip microcontroller;

[0011] The input end of the second analog-to-digital converter is connected to the output end of the four-tube buck-boost converter as the second input end of the control circuit, and the output end of the second analog-to-digital converter is connected to the second input end of the single-chip microcontroller;

[0012] The first output terminal of the single-chip microcontroller is connected to the input terminal of the first modulation circuit, and the second output terminal of the single-chip microcontroller is connected to the input terminal of the second modulation circuit;

[0013] The output end of the first modulation circuit is connected to the first input end of the half-bridge driving circuit as the first output end of the control circuit;

[0014] The output end of the second modulation circuit serves as the second output end of the control circuit and is connected to the second input end of the half-bridge driving circuit.

[0015] In some embodiments, a half-bridge driving circuit includes: a first half-bridge driver and a second half-bridge driver;

[0016] The input end of the first half-bridge driver is connected to the first output end of the control circuit as the first input end of the half-bridge drive circuit, the first output end of the first half-bridge driver is connected to the first control end of the four-tube buck-boost converter as the first output end of the half-bridge drive circuit, and the second output end of the first half-bridge driver is connected to the second control end of the four-tube buck-boost converter as the second output end of the half-bridge drive circuit;

[0017] The input end of the second half-bridge driver is connected to the second output end of the control circuit as the second input end of the half-bridge drive circuit, the first output end of the second half-bridge driver is connected to the third control end of the four-tube buck-boost converter as the third output end of the half-bridge drive circuit, and the second output end of the second half-bridge driver is connected to the fourth control end of the four-tube buck-boost converter as the fourth output end of the half-bridge drive circuit.

[0018] In some embodiments, the invention further includes: a first voltage dividing circuit and a second voltage dividing circuit;

[0019] Wherein, a first end of the first voltage divider circuit is connected to the input end of the four-tube buck-boost converter, a second end of the first voltage divider circuit is connected to the first input end of the control circuit, and a third end of the first voltage divider circuit is grounded;

[0020] The first end of the second voltage divider circuit is connected to the output end of the four-tube buck-boost converter, the second end of the second voltage divider circuit is connected to the second input end of the control circuit, and the third end of the second voltage divider circuit is grounded.

[0021] In some embodiments, the first voltage divider circuit includes: a first resistor and a second resistor;

[0022] Wherein, the first end of the first resistor is connected to the input end of the four-tube buck-boost converter as the first end of the first voltage divider circuit;

[0023] The second end of the first resistor is connected to the first end of the second resistor, and together serve as the second end of the first voltage divider circuit and are connected to the first input end of the control circuit;

[0024] The second end of the second resistor serves as the third end of the first voltage divider circuit and is grounded.

[0025] In some embodiments, the second voltage divider circuit includes: a third resistor and a fourth resistor;

[0026] The first end of the third resistor is connected to the output end of the four-tube buck-boost converter as the first end of the second voltage divider circuit;

[0027] The second end of the third resistor is connected to the first end of the fourth resistor, and together serve as the second end of the second voltage divider circuit and are connected to the second input end of the control circuit;

[0028] The second end of the fourth resistor is grounded as the third end of the second voltage divider circuit.

[0029] On the other hand, the present invention further provides a feedforward control method, which uses the above-mentioned feedforward control circuit, comprising:

[0030] Obtaining input voltage sampling values ​​and output voltage sampling values ​​of the four-tube buck-boost converter;

[0031] Determine the current working mode of the four-tube buck-boost converter according to the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter;

[0032] Based on the current working mode, a corresponding pulse width modulation signal is output; the pulse width modulation signal is output to the half-bridge drive circuit to generate a corresponding drive signal to control the four-tube buck-boost converter.

[0033] In some embodiments, determining the current operating mode of the four-tube buck-boost converter according to the difference between the input voltage sampling value and the output voltage of the four-tube buck-boost converter includes:

[0034] When the difference between the input voltage sampling value and the output voltage sampling value is within the preset error range, the operation mode of the four-tube buck-boost converter is the buck-boost mode;

[0035] When the difference between the input voltage sampling value and the output voltage sampling value is greater than the upper limit of the preset error range, the operation mode of the four-tube buck-boost converter is the buck mode;

[0036] When the difference between the input voltage sampling value and the output voltage sampling value is smaller than the lower limit of the preset error region, the operation mode of the four-tube buck-boost converter is the boost mode.

[0037] In some embodiments, when the operating mode is the buck mode, the first duty cycle corresponding to the pulse width modulation signal is inversely proportional to the input voltage sampling value;

[0038] When the working mode is the boost mode, the duty cycle difference between the standard value and the second duty cycle corresponding to the pulse width modulation signal is proportional to the input voltage sampling value;

[0039] When the working mode is the buck-boost mode, in the first half cycle, the first duty cycle is inversely proportional to the input voltage sampling value; in the second half cycle, the duty cycle difference is proportional to the input voltage sampling value.

[0040] In some embodiments, when the operating mode is the buck mode, outputting a corresponding pulse width modulation signal based on the current operating mode includes:

[0041] Obtain the current input voltage sampling value and the previous input voltage sampling value, and determine the corresponding voltage ratio according to the current input voltage sampling value and the previous input voltage sampling value;

[0042] Obtaining an initial first duty cycle corresponding to a pulse width modulation signal corresponding to the last input voltage sampling value;

[0043] Determining a first duty cycle after feedforward compensation corresponding to the voltage ratio and the initial first duty cycle;

[0044] The output duty cycles are respectively a first duty cycle after feedforward compensation and a pulse width modulation signal of zero.

[0045] In some embodiments, when the operating mode is the boost mode, outputting a corresponding pulse width modulation signal based on the current operating mode includes:

[0046] Obtain the current input voltage sampling value and the previous input voltage sampling value, and determine the corresponding voltage ratio according to the current input voltage sampling value and the previous input voltage sampling value;

[0047] Obtaining an initial second duty cycle corresponding to the pulse width modulation signal corresponding to the last input voltage sampling value, and determining a corresponding initial duty cycle difference according to the standard value and the initial second duty cycle;

[0048] Determining a second duty cycle after feedforward compensation corresponding to a difference between the standard value, the voltage ratio, and the initial duty cycle;

[0049] The output duty cycle is a pulse width modulation signal having a standard value and a second duty cycle after feedforward compensation.

[0050] In some embodiments, when the operating mode is the buck-boost mode, outputting a corresponding pulse width modulation signal based on the current operating mode includes:

[0051] Obtain the current input voltage sampling value and the previous input voltage sampling value, and determine the corresponding voltage ratio according to the current input voltage sampling value and the previous input voltage sampling value;

[0052] Obtaining an initial first duty cycle and an initial second duty cycle corresponding to a pulse width modulation signal corresponding to the last input voltage sampling value, and determining a corresponding initial duty cycle difference according to a standard value and the initial second duty cycle;

[0053] Determining a first duty cycle after feedforward compensation corresponding to the voltage ratio and the initial first duty cycle;

[0054] Determining a second duty cycle after feedforward compensation corresponding to a difference between the standard value, the voltage ratio, and the initial duty cycle;

[0055] In the first half cycle, the output duty cycle is respectively the first duty cycle after feedforward compensation and a pulse width modulation signal of zero;

[0056] In the second half cycle, a pulse width modulation signal with a duty cycle of a standard value and a second duty cycle after feedforward compensation is output.

[0057] In another aspect, the present invention further provides an electronic device, comprising:

[0058] memory for storing computer programs;

[0059] A processor is used to execute a computer program to implement the steps of the above-mentioned feedforward control method.

[0060] On the other hand, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above-mentioned feedforward control method when executed by a processor.

[0061] On the other hand, the present invention further provides a computer program product, comprising a computer program / instruction, which implements the steps of the above feedforward control method when executed by a processor.

[0062] As can be seen from the above technical solution, a feedforward control circuit includes: a control circuit and a half-bridge drive circuit; wherein the first input terminal and the second input terminal of the control circuit are respectively connected to the input terminal and the output terminal of the four-tube buck-boost converter, and are used to determine the current operating mode of the four-tube buck-boost converter based on the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter, and output a corresponding pulse width modulation signal based on the current operating mode; the first input terminal and the second input terminal of the half-bridge drive circuit are respectively connected to the first output terminal and the second output terminal of the control circuit, and the four output terminals of the half-bridge drive circuit are respectively connected to the four control terminals of the four-tube buck-boost converter, and are used to generate corresponding drive signals based on the pulse width modulation signal to control the four-tube buck-boost converter. As can be seen from this, the control circuit in the present invention samples the input voltage sampling value and the output voltage sampling value in each switching cycle, and outputs corresponding pulse width modulation signals for the three different operating modes of the four-tube buck-boost converter to offset the impact of the input voltage disturbance on the output voltage, thereby achieving the purpose of maintaining the output voltage stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0064] Figure 1 A circuit diagram of a four-tube buck-boost converter provided by the prior art;

[0065] Figure 2 A structural diagram of a feedforward control circuit provided by an embodiment of the present invention;

[0066] Figure 3 A circuit diagram of a four-tube buck-boost converter provided by an embodiment of the present invention;

[0067] Figure 4 A circuit diagram of a feedforward control circuit provided by an embodiment of the present invention;

[0068] Figure 5 A flow chart of a feedforward control method provided by an embodiment of the present invention;

[0069] Figure 6 A specific flow chart of a feedforward control method provided by an embodiment of the present invention;

[0070] Figure 7 A structural diagram of an electronic device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0071] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0072] The terms "including" and "having," as used in the present description and accompanying drawings, and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements and may include steps or elements that are not listed.

[0073] In order to enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0074] Next, a feedforward control circuit, a feedforward control method, a device, a medium, and a product provided by an embodiment of the present invention are described in detail.

[0075] Figure 2 A structural diagram of a feedforward control circuit provided by an embodiment of the present invention is shown in FIG. Figure 2 As shown, it includes: a control circuit 1 and a half-bridge drive circuit 2. In addition, Figure 2The system also includes a four-tube buck-boost converter 3. The connection relationship is as follows: the first and second input terminals of the control circuit 1 are connected to the input and output terminals of the four-tube buck-boost converter 3, respectively; the first and second input terminals of the half-bridge drive circuit 2 are connected to the first and second output terminals of the control circuit 1, respectively; and the four output terminals of the half-bridge drive circuit 2 are connected to the four control terminals of the four-tube buck-boost converter 3, respectively.

[0076] In an embodiment, the four-tube buck-boost converter 3 provided by the present invention is as follows: Figure 3 As shown, it includes a first MOS transistor Q1, a second MOS transistor Q2, a third MOS transistor Q3, a fourth MOS transistor Q4 and an inductor L1. The connection relationship is as follows: the gate of the first MOS transistor Q1 is connected to the first output terminal of the half-bridge drive circuit 2 as the first control terminal of the four-tube buck-boost converter 3, the drain of the first MOS transistor Q1 is connected to the first input terminal of the control circuit 1 as the input terminal of the four-tube buck-boost converter 3, the source of the first MOS transistor Q1 is connected to the drain of the second MOS transistor Q2 and the first terminal of the inductor L1; the gate of the second MOS transistor Q2 is connected to the second output terminal of the half-bridge drive circuit 2 as the second control terminal of the four-tube buck-boost converter 3; the gate of the third MOS transistor Q3 is connected to the second output terminal of the half-bridge drive circuit 2. The third control terminal of the four-tube buck-boost converter 3 is connected to the third output terminal of the half-bridge drive circuit 2. The drain of the third MOS transistor Q3 is connected to the second input terminal of the control circuit 1 as the output terminal of the four-tube buck-boost converter 3. The source of the third MOS transistor Q3 is connected to the drain of the fourth MOS transistor Q4 and the second end of the inductor L1. The gate of the fourth MOS transistor Q4 is connected to the fourth output terminal of the half-bridge drive circuit 2 as the fourth control terminal of the four-tube buck-boost converter 3. The source of the second MOS transistor Q2 is connected to the source of the fourth MOS transistor Q4 and is grounded.

[0077] In this embodiment, the first and second input terminals of the control circuit 1 are respectively connected to the input terminal (the drain of the first MOS transistor Q1) and the output terminal (the drain of the third MOS transistor Q3) of the four-transistor buck-boost converter 3, and are used to collect the input voltage sample value VIN and the output voltage sample value VOUT of the four-transistor buck-boost converter 3. The current operating mode of the four-transistor buck-boost converter 3 is then determined based on the difference between the input voltage sample value VIN and the output voltage sample value VOUT. Different operating modes employ different adjustment schemes when the input voltage fluctuates, and thus output a corresponding pulse-width modulation signal based on the current operating mode. Essentially, in different operating modes, when the input voltage fluctuates, to ensure output voltage stability, a pulse-width modulation signal is used to compensate for fluctuations in the input voltage. This offsets the impact of the input voltage disturbance on the output voltage, thereby maintaining output voltage stability.

[0078] The first input terminal and the second input terminal of the half-bridge driver circuit 2 are respectively connected to the first output terminal and the second output terminal of the control circuit 1. The half-bridge driver circuit 2 obtains two sets of pulse width modulation signals output by the first output terminal and the second output terminal of the control circuit 1. Then, the half-bridge driver circuit 2 generates four sets of drive signals (Q1_GATE, Q2_GATE, Q3_GATE, and Q1_GATE) based on the two sets of pulse width modulation signals. The half-bridge driver circuit 2 is connected to the four control terminals (the gate of the first MOS transistor Q1, the gate of the second MOS transistor Q2, the gate of the third MOS transistor Q3, and the gate of the fourth MOS transistor Q4) of the four-transistor buck-boost converter 3, and inputs a corresponding set of drive signals thereto. The half-bridge driver circuit 2 controls the on / off states of the MOS transistors (the first MOS transistor Q1, the second MOS transistor Q2, the third MOS transistor Q3, and the fourth MOS transistor Q4), thereby adjusting the duty cycle of the signal passing through the four-transistor buck-boost converter 3. After the duty cycle of the signal is adjusted, the product or ratio of the input voltage sampling value VIN and the adjusted duty cycle is equal to the output voltage sampling value VOUT.

[0079] The current working mode of the four-tube buck-boost converter 3 is determined according to the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT: when the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT is within the preset error range, the working mode of the four-tube buck-boost converter is the buck-boost mode. It can also be understood that when the input voltage sampling value VIN and the output voltage sampling value VOUT are close, the working mode of the four-tube buck-boost converter is the buck-boost mode; when the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT is greater than the preset error range, the four-tube buck-boost converter is in the buck-boost mode. When the upper limit value of the domain range is reached, the working mode of the four-tube buck-boost converter is the buck mode, which can also be understood as the input voltage sampling value VIN is greater than the output voltage sampling value VOUT, and the working mode of the four-tube buck-boost converter is the buck mode; when the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT is less than the lower limit value of the preset error area range, the working mode of the four-tube buck-boost converter is the boost mode, which can also be understood as the input voltage sampling value VIN is less than the output voltage sampling value VOUT, and the working mode of the four-tube buck-boost converter is the buck-boost mode.

[0080] For example, two pulse-width modulation signals, PWM1 and PWM2, have corresponding duty cycles of D1 and D2. PWM1 controls the first MOS transistor Q1 and / or the second MOS transistor Q2; PWM2 controls the third MOS transistor Q3 and / or the fourth MOS transistor Q4. When the four-transistor buck-boost converter 3 operates in buck mode, the first MOS transistor Q1 and the second MOS transistor Q2 alternately conduct, the third MOS transistor Q3 is always on, and the fourth MOS transistor Q4 is always off. Based on the first and fourth MOS transistors Q1 and Q2, the duty cycle of PWM2 is zero. The control circuit 1 adjusts the output voltage by varying the duty cycle D1 of PWM1. According to the buck circuit's output voltage calculation formula (VOUT = VIN * D1), to maintain a constant output voltage when the input voltage is disturbed, the value of D1 can be varied in the opposite direction of the input voltage to keep the product of the two constant. However, the specific duty cycle adjustment compensation amplitude needs to be determined based on the current input voltage sampling value, the previous input voltage sampling value, and the current duty cycle.

[0081] As can be seen from the above technical solution, a feedforward control circuit includes: a control circuit and a half-bridge drive circuit; wherein the first input terminal and the second input terminal of the control circuit are respectively connected to the input terminal and the output terminal of the four-tube buck-boost converter, and are used to determine the current operating mode of the four-tube buck-boost converter based on the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter, and output a corresponding pulse width modulation signal based on the current operating mode; the first input terminal and the second input terminal of the half-bridge drive circuit are respectively connected to the first output terminal and the second output terminal of the control circuit, and the four output terminals of the half-bridge drive circuit are respectively connected to the four control terminals of the four-tube buck-boost converter, and are used to generate corresponding drive signals based on the pulse width modulation signal to control the four-tube buck-boost converter. As can be seen from this, the control circuit in the present invention samples the input voltage sampling value and the output voltage sampling value in each switching cycle, and outputs corresponding pulse width modulation signals for the three different operating modes of the four-tube buck-boost converter to offset the impact of the input voltage disturbance on the output voltage, thereby achieving the purpose of maintaining the output voltage stability.

[0082] In some embodiments, as Figure 4As shown, the control circuit 1 includes: a first analog-to-digital converter ADC1, a second analog-to-digital converter ADC2, a single-chip microcontroller MCU, a first modulation circuit 11, and a second modulation circuit 12. The connection relationship at this time is as follows: the input end of the first analog-to-digital converter ADC1 is connected to the input end of the four-tube buck-boost converter 3 as the first input end of the control circuit 1, and the output end of the first analog-to-digital converter ADC1 is connected to the first input end of the single-chip microcontroller MCU; the input end of the second analog-to-digital converter ADC2 is connected to the output end of the four-tube buck-boost converter 3 as the second input end of the control circuit 1, and the output end of the second analog-to-digital converter ADC2 is connected to the second input end of the single-chip microcontroller MCU; the first output end of the single-chip microcontroller MCU is connected to the input end of the first modulation circuit 11, and the second output end of the single-chip microcontroller MCU is connected to the input end of the second modulation circuit 12; the output end of the first modulation circuit 11 is connected to the first input end of the half-bridge drive circuit 2 as the first output end of the control circuit 1; and the output end of the second modulation circuit 12 is connected to the second input end of the half-bridge drive circuit 2 as the second output end of the control circuit 1.

[0083] like Figure 4 As shown, the half-bridge driver circuit 2 includes: a first half-bridge driver DRIVER1 and a second half-bridge driver DRIVER2. The connection relationship is as follows: the input end of the first half-bridge driver DRIVER1 is connected to the first output end of the control circuit 1 as the first input end of the half-bridge driver circuit 2; the first output end of the first half-bridge driver DRIVER1 is connected to the first control end of the four-tube buck-boost converter 3 as the first output end of the half-bridge driver circuit 2; the second output end of the first half-bridge driver DRIVER1 is connected to the second control end of the four-tube buck-boost converter 3 as the second output end of the half-bridge driver circuit 2; the input end of the second half-bridge driver DRIVER2 is connected to the second output end of the control circuit 1 as the second input end of the half-bridge driver circuit 2; the first output end of the second half-bridge driver DRIVER2 is connected to the third control end of the four-tube buck-boost converter 3 as the third output end of the half-bridge driver circuit 2; and the second output end of the second half-bridge driver DRIVER2 is connected to the fourth control end of the four-tube buck-boost converter 3 as the fourth output end of the half-bridge driver circuit 2.

[0084] Based on the above structure, Figure 4As shown, the control circuit 1 further includes: a first voltage divider circuit and a second voltage divider circuit. The first voltage divider circuit includes: a first resistor R1 and a second resistor R2; the second voltage divider circuit includes: a third resistor R3 and a fourth resistor R4. The connection relationship is as follows: the first end of the first resistor R1 serves as the first end of the first voltage divider circuit and is connected to the input end of the four-tube buck-boost converter 3; the second end of the first resistor R1 is connected to the first end of the second resistor R2, and together they serve as the second end of the first voltage divider circuit and are connected to the first input end of the control circuit 1; the second end of the second resistor R2 serves as the third end of the first voltage divider circuit and is grounded; the first end of the third resistor R3 serves as the first end of the second voltage divider circuit and is connected to the output end of the four-tube buck-boost converter 3; the second end of the third resistor R3 is connected to the first end of the fourth resistor R4, and together they serve as the second end of the second voltage divider circuit and are connected to the second input end of the control circuit 1; the second end of the fourth resistor R4 serves as the third end of the second voltage divider circuit and is grounded.

[0085] In this embodiment, the four-transistor buck-boost converter 3 is digitally controlled by a single-chip microcontroller (MCU). The input voltage sample value VIN is connected to the input of the first analog-to-digital converter ADC1 after being divided by a first resistor R1 and a second resistor R2. The output voltage sample value VOUT is connected to the input of the second analog-to-digital converter ADC2 after being divided by a third resistor R3 and a fourth resistor R4. The single-chip microcontroller MCU sends a pulse-width modulated signal to a first half-bridge driver DRIVER1 and a second half-bridge driver DRIVER2. Each half-bridge driver outputs a pair of complementary drive signals to the upper and lower transistors of the same bridge arm. Q1_GATE and Q2_GATE are complementary drive signals that respectively drive the first and second MOS transistors Q1 and Q2, and Q3_GATE and Q4_GATE are complementary drive signals that respectively drive the third and fourth MOS transistors Q3 and Q4.

[0086] The duty cycle is defined as the percentage of the switch on-time, Ton, within a switching cycle, Tsw. For the left bridge arm (buck circuit), the first MOS transistor Q1 is on and the second MOS transistor Q2 is off, representing Ton. During this time, energy is being stored in inductor L1. The first MOS transistor Q1 is off and the second MOS transistor Q2 is on, representing Toff. For the right bridge arm (boost circuit), the fourth MOS transistor Q4 is on and the third MOS transistor Q3 is off, representing Ton. During this time, energy is being stored in inductor L1. The fourth MOS transistor Q4 is off and the third MOS transistor Q3 is on, representing Toff. The duty cycle of PWM1 is D1, and the duty cycle of PWM2 is D2.

[0087] In summary, the two sets of pulse width modulation signals are PWM1 and PWM2, and the corresponding duty cycles are D1 and D2. PWM1 controls the first MOS transistor Q1 and / or the second MOS transistor Q2; PWM2 controls the third MOS transistor Q3 and / or the fourth MOS transistor Q4.

[0088] The overall principle is as follows: When the four-transistor boost / buck converter 3 operates in step-down (buck) mode, the first and second MOS transistors Q1 and Q2 alternately conduct, the third MOS transistor Q3 is always on, and the fourth MOS transistor Q4 is always off. Based on the first and fourth MOS transistors Q1 and Q4, the duty cycle of PWM2 is zero. The control circuit 1 adjusts the output voltage by varying the duty cycle D1 of PWM1. According to the buck circuit's output voltage calculation formula (VOUT = VIN * D1), to maintain a constant output voltage when the input voltage is disturbed, the value of D1 can be varied so that it changes in the opposite direction of the input voltage, thereby keeping the product of the two constant.

[0089] When the four-transistor buck-boost converter 3 operates in boost mode, the third and fourth MOS transistors Q3 and Q4 alternately conduct, the first MOS transistor Q1 remains on, and the second MOS transistor Q2 remains off. Based on the first and fourth MOS transistors, the duty cycle of PWM1 is 1. Control circuit 1 adjusts the output voltage by varying the duty cycle D2 of PWM2. According to the boost circuit's output voltage calculation formula (VOUT = VIN / (1-D2), to maintain a constant output voltage when the input voltage fluctuates, D2 can be varied so that 1-D2 changes in the same direction as the input voltage, thereby maintaining the product of the two constant.

[0090] When the four-transistor buck-boost converter 3 operates in buck-boost mode, the first MOS transistor Q1 and the second MOS transistor Q2 are alternately conductive in the first half of a switching cycle, and the third MOS transistor Q3 and the fourth MOS transistor Q4 are alternately conductive in the second half. This means the circuit operates in buck mode in the first half of the switching cycle and in boost mode in the second half. Control circuit 1 adjusts the output voltage by varying duty cycles D1 and D2, respectively. In other words, duty cycles D1 and D2 can be adjusted according to the buck and boost calculation formulas, respectively, to offset the effects of input voltage disturbances.

[0091] It should be noted that the embodiment provided by the present invention is only one possible implementation method, but is not limited to this implementation method and can be set according to user needs.

[0092] In addition, since the present invention primarily prevents the output voltage of the four-tube buck-boost converter 3 from being affected by input voltage fluctuations in different operating modes, a feedforward control circuit is provided. However, during operation, components may overheat or age. Therefore, a removable, portable detection device can also be provided, which has two functions. When the detection device is connected to the output and input terminals of the four-tube buck-boost converter 3, the current input voltage and the voltage waveform corresponding to the output voltage are acquired and compared in real time. In principle, the output voltage should remain stable. If the waveform corresponding to the output voltage is unstable, it indicates that there is a problem with the compensation amplitude of the feedforward compensation for the duty cycles of PWM1 and PWM2. The cause of the compensation amplitude problem is then predicted based on the current usage time of each component and the current voltage signal. This is most likely due to component aging or overheating.

[0093] After predicting the cause of the compensation amplitude problem, the detection device is connected to the feedforward compensation circuit and the circuit is first tested based on the cause of the problem. If the analysis of the cause of the problem is found to be incorrect during the test, the entire feedforward compensation circuit is then fully analyzed and tested, thereby achieving the goal of circuit testing and quickly determining the cause of the problem. For example, if the cause of the compensation amplitude problem is predicted to be excessive component temperature, the temperature parameters of each component are first obtained to identify the component whose temperature parameters do not meet the standard. If all temperature components meet the standard, the various operating parameters of each component in the current circuit are obtained and analyzed.

[0094] As can be seen, the present invention first analyzes the impact of input voltage variations on the output voltage of a four-tube buck-boost converter operating in buck, boost, and buck-boost modes. It then performs feedforward compensation on the duty cycles of PWM1 and PWM2, ensuring that the compensated duty cycles offset the impact of input voltage variations and maintain a stable output voltage.

[0095] On the other hand, the present invention also provides a feedforward control method, which is applied to the above feedforward control circuit, such as Figure 5 As shown, the following steps are included:

[0096] S10: Obtaining input voltage sampling values ​​and output voltage sampling values ​​of the four-tube buck-boost converter.

[0097] S11: Determine a current operating mode of the four-tube buck-boost converter according to a difference between an input voltage sampling value and an output voltage sampling value of the four-tube buck-boost converter.

[0098] S12: Outputting a corresponding pulse width modulation signal based on the current working mode; outputting the pulse width modulation signal to the half-bridge drive circuit to generate a corresponding drive signal to control the four-tube buck-boost converter.

[0099] In one embodiment, a feedforward control circuit includes a control circuit and a half-bridge drive circuit. The circuits are connected as follows: the first and second input terminals of the control circuit are connected to the input and output terminals of a four-tube buck-boost converter, respectively; the first and second input terminals of the half-bridge drive circuit are connected to the first and second output terminals of the control circuit, respectively; and the four output terminals of the half-bridge drive circuit are connected to the four control terminals of the four-tube buck-boost converter, respectively. The control circuit is configured to collect input voltage sampling values ​​VIN and output voltage sampling values ​​VOUT of the four-tube buck-boost converter. The current operating mode of the four-tube buck-boost converter is then determined based on the difference between the input voltage sampling values ​​VIN and the output voltage sampling values ​​VOUT. Different operating modes employ different adjustment schemes when the input voltage fluctuates, thereby outputting a pulse-width modulation signal corresponding to the current operating mode. This pulse-width modulation signal primarily performs feedforward compensation when the input voltage fluctuates, offsetting the impact of input voltage disturbances on the output voltage and maintaining output voltage stability. The first input terminal and the second input terminal of the half-bridge drive circuit are respectively connected to the first output terminal and the second output terminal of the control circuit 1, and two groups of pulse width modulation signals output by the first output terminal and the second output terminal of the control circuit 1 are obtained. Then, four groups of drive signals are generated according to the two groups of pulse width modulation signals, and one group of corresponding drive signals is input to the four control terminals of the four-tube buck-boost converter respectively to control the conduction and shutdown of the MOS tube, thereby achieving the purpose of adjusting the duty cycle of the signal passing through the four-tube buck-boost converter. After the duty cycle of the signal is adjusted, the product or ratio of the input voltage sampling value VIN and the adjusted duty cycle is equal to the output voltage sampling value VOUT.

[0100] Among them, step S11: determining the current operating mode of the four-tube buck-boost converter based on the difference between the input voltage sampling value and the output voltage of the four-tube buck-boost converter is specifically implemented as follows: when the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT is within a preset error range, the operating mode of the four-tube buck-boost converter is the buck-boost mode; when the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT is greater than the upper limit of the preset error range, the operating mode of the four-tube buck-boost converter is the buck mode; when the difference between the input voltage sampling value VIN and the output voltage sampling value VOUT is less than the lower limit of the preset error range, the operating mode of the four-tube buck-boost converter is the boost mode.

[0101] In each switching cycle, the input voltage sampling value VIN and the output voltage sampling value VOUT are sampled once. The initial duty cycle can be calculated based on the error between the output voltage sampling value VOUT and the output voltage set value Vset after PID adjustment (Proportional Integral Derivative, proportional unit, integration, differentiation). The calculation result is that the duty cycle of PWM1 is D1 and the duty cycle of PWM2 is D2.

[0102] In buck mode, the first and second MOS transistors Q1 and Q2 are alternately turned on, the third MOS transistor Q3 is always on, and the fourth MOS transistor Q4 is always off. Therefore, the duty cycle D2 of PWM2 is 0. The MCU adjusts the output voltage by changing the duty cycle D1 of PWM1. Feedforward control is added to the duty cycle D1 of PWM1, so:

[0103] ;

[0104] In the above formula, Indicates the current input voltage sampling value, Indicates the last input voltage sampling value, Indicates the duty cycle of PWM1 after feedforward control compensation. In the above formula, if the input voltage does not change, then the current sampling value is equal to the previous sampling value, and the formula becomes , and the result is the same as that without feedforward control compensation; but if the input voltage changes, the feedforward compensation The input voltage sampling value will be The size is inversely proportional. According to the output voltage calculation formula of the buck circuit VOUT=VIN*D1, after feedforward compensation, The influence of the input voltage change is offset, so that the output voltage sampling value VOUT remains unchanged.

[0105] In boost mode, the third MOS transistor Q3 and the fourth MOS transistor Q4 are turned on alternately, the first MOS transistor Q1 is always on, and the second MOS transistor Q2 is always off. Therefore, the duty cycle of PWM1 is 1 (standard value). The MCU adjusts the output voltage by changing the duty cycle D2 of PWM2. Feedforward control is added to the duty cycle D2 of PWM2, so:

[0106] ;

[0107] In the above formula, Indicates the current input voltage sampling value, Indicates the last input voltage sampling value, Indicates the duty cycle of PWM2 after feedforward control compensation. In the formula, if the input voltage does not change, then the current sampling value is equal to the previous sampling value, and the formula becomes , and the result is the same as that without feedforward control compensation; but if the input voltage changes, the feedforward compensation The input voltage sampling value will be The size is proportional to the boost circuit output voltage calculation formula VOUT=VIN / (1-D2). The influence of the input voltage change is offset, so that the output voltage sampling value VOUT remains unchanged.

[0108] For the buck-boost mode, the first MOS transistor Q1 and the second MOS transistor Q2 are turned on alternately in the first half of a cycle, and the third MOS transistor Q3 and the fourth MOS transistor Q4 are turned on alternately in the second half of the cycle. It can be considered that the circuit operates in buck mode in the first half of the switching cycle and in boost mode in the second half. Therefore, the duty cycles D1 and D2 are changed to adjust the output voltage. Substituting the PWM1 duty cycle D1 and the PWM2 duty cycle D2 into the above two formulas, the duty cycle after feedforward compensation is obtained. and In the first half of the switching cycle, the inverter works in buck mode. If the input voltage changes, the feedforward compensation The input voltage sampling value will be The magnitude is inversely proportional to the input voltage, which offsets the effect of input voltage changes. In the second half of the switching cycle, the boost mode is used. If the input voltage changes, the feedforward compensation The input voltage sampling value will be The magnitudes of the two are directly proportional, offsetting the effects of input voltage changes. Therefore, the two can offset the effects of input voltage disturbances, thereby maintaining the output voltage sampling value VOUT unchanged.

[0109] In summary, the overall process of the feedforward control method provided by the present invention is as follows: Figure 6 As shown, the following steps are included:

[0110] S20: Acquire input voltage sampling value and output voltage sampling value.

[0111] S21: Determine whether the difference between the input voltage sampling value and the output voltage sampling value is greater than an upper limit of a preset error range.

[0112] S22: If yes, the operating mode of the four-tube buck-boost converter is buck mode.

[0113] S23: The error between the output voltage sampling value and the output voltage setting value is calculated and then PID adjusted to obtain the duty cycle D1.

[0114] S24: Calculate the duty cycle after feedforward compensation based on duty cycle D1 , and enter step S32.

[0115] S25: If not, determine whether the difference between the input voltage sampling value and the output voltage sampling value is less than the lower limit of the preset error range.

[0116] S26: If yes, the operating mode of the four-tube buck-boost converter is the boost mode.

[0117] S27: The error between the output voltage sampling value and the output voltage setting value is calculated and then PID-adjusted to obtain the duty cycle D2.

[0118] S28: Calculate the duty cycle after feedforward compensation based on duty cycle D2 , and enter step S32.

[0119] S29: If not, the operating mode of the four-tube buck-boost converter is the buck-boost mode.

[0120] S30: The error between the output voltage sampling value and the output voltage setting value is adjusted by PID and then calculated to obtain duty ratios D1 and D2.

[0121] S31: Calculate the duty cycle after feedforward compensation based on duty cycles D1 and D2 and .

[0122] S32: End.

[0123] Since steps S20 to S32 are a summary of the above embodiments, the present invention will not elaborate on them here.

[0124] As can be seen from the above technical solution, a feedforward control method is applied to a feedforward control circuit, including: obtaining an input voltage sampling value and an output voltage sampling value of a four-tube buck-boost converter; determining the current operating mode of the four-tube buck-boost converter based on the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter; outputting a corresponding pulse width modulation signal based on the current operating mode; and outputting the pulse width modulation signal to a half-bridge drive circuit to generate a corresponding drive signal to control the four-tube buck-boost converter. It can be seen that the feedforward control method of the present invention samples the input voltage sampling value and the output voltage sampling value in each switching cycle, and outputs corresponding pulse width modulation signals for the three different operating modes of the four-tube buck-boost converter, so as to offset the influence of the input voltage disturbance on the output voltage and achieve the purpose of maintaining the output voltage stability.

[0125] Figure 7 A structural diagram of an electronic device provided by an embodiment of the present invention, such as Figure 7 As shown, the electronic device includes: a memory 60 for storing computer programs;

[0126] The processor 61 is configured to implement the steps of the feedforward control method of the above embodiment when executing a computer program.

[0127] The electronic device provided in this embodiment may include but is not limited to a smart phone, a tablet computer, a laptop computer, or a desktop computer.

[0128] The processor 61 may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor 61 may be implemented using at least one of the following hardware forms: a digital signal processing (DSP), a field-programmable gate array (FPGA), or a programmable logic array (PLA). The processor 61 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a central processing unit (CPU); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 61 may be integrated with a graphics processing unit (GPU), which is responsible for rendering and drawing content required to be displayed on the display screen. In some embodiments, the processor 61 may also include an artificial intelligence (AI) processor for handling computational operations related to machine learning.

[0129] The memory 60 may include one or more computer-readable storage media, which may be non-transitory. The memory 60 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 60 is at least used to store the following computer program 601, wherein, after the computer program is loaded and executed by the processor 61, it can implement the relevant steps of the feedforward control method disclosed in any of the aforementioned embodiments. In addition, the resources stored in the memory 60 may also include an operating system 602 and data 603, etc., and the storage method may be temporary storage or permanent storage. Among them, the operating system 602 may include Windows, Unix, Linux, etc.

[0130] In some embodiments, the electronic device may further include a display screen 62 , an input / output interface 63 , a communication interface 64 , a power supply 65 , and a communication bus 66 .

[0131] Those skilled in the art will understand that Figure 7 The structure shown in the figure does not constitute a limitation of the electronic device, and may include more or fewer components than shown in the figure.

[0132] It is understood that if the feedforward control method in the above embodiment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the current technology, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and executes all or part of the steps of the various embodiments of the present invention. The aforementioned storage medium includes: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, a magnetic disk, or an optical disk, and other media that can store program code.

[0133] Based on this, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the feedforward control method described above are implemented.

[0134] Based on this, an embodiment of the present invention further provides a computer program product, including a computer program / instruction, which implements the steps of the above-mentioned feedforward control method when executed by a processor.

[0135] The above describes in detail a feedforward control circuit, feedforward control method, device, medium, and product provided by the embodiments of the present invention. The various embodiments are described in a progressive manner in this specification, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between the various embodiments can be referenced to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For relevant details, refer to the description of the methods.

[0136] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0137] The above is a detailed introduction to a feedforward control circuit, feedforward control method, device, medium and product provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A feedforward control circuit, characterized in that: include: Control circuit and half-bridge drive circuit; The first input terminal and the second input terminal of the control circuit are respectively connected to the input terminal and the output terminal of the four-tube buck-boost converter, and are used to determine the current operating mode of the four-tube buck-boost converter according to the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter, and output a corresponding pulse width modulation signal based on the current operating mode; The first input terminal and the second input terminal of the half-bridge drive circuit are respectively connected to the first output terminal and the second output terminal of the control circuit, and the four output terminals of the half-bridge drive circuit are respectively connected to the four control terminals of the four-tube buck-boost converter, and are used to generate corresponding drive signals according to the pulse width modulation signal to control the four-tube buck-boost converter; wherein: The determining the current operating mode of the four-tube buck-boost converter according to the difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter includes: When the difference between the input voltage sampling value and the output voltage sampling value is within a preset error range, the operation mode of the four-tube buck-boost converter is the buck-boost mode; When the difference between the input voltage sampling value and the output voltage sampling value is greater than the upper limit of the preset error range, the operating mode of the four-tube buck-boost converter is the buck mode; When the difference between the input voltage sampling value and the output voltage sampling value is less than the lower limit of the preset error range, the operation mode of the four-tube buck-boost converter is the boost mode; When the operating mode is the step-down mode, the first duty cycle of the pulse width modulation signal after feed-forward compensation is inversely proportional to the current input voltage sampling value; wherein the first duty cycle after feed-forward compensation is obtained based on a voltage ratio corresponding to a previous input voltage sampling value and a current input voltage sampling value, combined with an initial first duty cycle; When the operating mode is the boost mode, a duty cycle difference between the standard value and the second duty cycle after feed-forward compensation corresponding to the pulse width modulation signal is proportional to the current input voltage sampling value; wherein the duty cycle difference is obtained based on a voltage ratio corresponding to the current input voltage sampling value and the previous input voltage sampling value, and a difference between the standard value and the initial second duty cycle; When the working mode is the buck-boost mode, in the first half cycle, the first duty cycle after the feedforward compensation is inversely proportional to the current input voltage sampling value; in the second half cycle, the duty cycle difference is proportional to the current input voltage sampling value.

2. The feedforward control circuit according to claim 1, characterized in that: The control circuit includes: a first analog-to-digital converter, a second analog-to-digital converter, a single-chip microcontroller, a first modulation circuit and a second modulation circuit; The input end of the first analog-to-digital converter is connected to the input end of the four-tube buck-boost converter as the first input end of the control circuit, and the output end of the first analog-to-digital converter is connected to the first input end of the single-chip microcontroller; The input end of the second analog-to-digital converter is connected to the output end of the four-tube buck-boost converter as the second input end of the control circuit, and the output end of the second analog-to-digital converter is connected to the second input end of the single-chip microcontroller; The first output terminal of the single-chip microcontroller is connected to the input terminal of the first modulation circuit, and the second output terminal of the single-chip microcontroller is connected to the input terminal of the second modulation circuit; The output end of the first modulation circuit is connected to the first input end of the half-bridge driving circuit as the first output end of the control circuit; The output end of the second modulation circuit serves as the second output end of the control circuit and is connected to the second input end of the half-bridge driving circuit.

3. The feedforward control circuit according to claim 1, wherein: The half-bridge driving circuit includes: a first half-bridge driver and a second half-bridge driver; The input end of the first half-bridge driver is connected to the first output end of the control circuit as the first input end of the half-bridge drive circuit, the first output end of the first half-bridge driver is connected to the first control end of the four-tube buck-boost converter as the first output end of the half-bridge drive circuit, and the second output end of the first half-bridge driver is connected to the second control end of the four-tube buck-boost converter as the second output end of the half-bridge drive circuit; The input end of the second half-bridge driver is connected to the second output end of the control circuit as the second input end of the half-bridge drive circuit, the first output end of the second half-bridge driver is connected to the third control end of the four-tube buck-boost converter as the third output end of the half-bridge drive circuit, and the second output end of the second half-bridge driver is connected to the fourth control end of the four-tube buck-boost converter as the fourth output end of the half-bridge drive circuit.

4. The feedforward control circuit according to claim 2, characterized in that: Also includes: a first voltage dividing circuit and a second voltage dividing circuit; Wherein, the first end of the first voltage divider circuit is connected to the input end of the four-tube buck-boost converter, the second end of the first voltage divider circuit is connected to the first input end of the control circuit, and the third end of the first voltage divider circuit is grounded; A first end of the second voltage divider circuit is connected to the output end of the four-tube buck-boost converter, a second end of the second voltage divider circuit is connected to the second input end of the control circuit, and a third end of the second voltage divider circuit is grounded.

5. The feedforward control circuit according to claim 4, characterized in that: The first voltage divider circuit includes: a first resistor and a second resistor; Wherein, the first end of the first resistor is connected to the input end of the four-tube buck-boost converter as the first end of the first voltage divider circuit; The second end of the first resistor is connected to the first end of the second resistor, and together serve as the second end of the first voltage divider circuit and are connected to the first input end of the control circuit; The second end of the second resistor serves as the third end of the first voltage divider circuit and is grounded.

6. The feedforward control circuit according to claim 4, characterized in that: The second voltage divider circuit includes: a third resistor and a fourth resistor; Wherein, the first end of the third resistor serves as the first end of the second voltage divider circuit and is connected to the output end of the four-tube buck-boost converter; The second end of the third resistor is connected to the first end of the fourth resistor, and together serve as the second end of the second voltage divider circuit and are connected to the second input end of the control circuit; The second end of the fourth resistor serves as the third end of the second voltage divider circuit and is grounded.

7. A feedforward control method, characterized in that: The feedforward control circuit according to claim 1 comprises: Obtaining input voltage sampling values ​​and output voltage sampling values ​​of the four-tube buck-boost converter; Determining a current operating mode of the four-tube buck-boost converter according to a difference between the input voltage sampling value and the output voltage sampling value of the four-tube buck-boost converter; A corresponding pulse width modulation signal is output based on the current working mode; and the pulse width modulation signal is output to a half-bridge drive circuit to generate a corresponding drive signal to control the four-tube buck-boost converter.

8. The feedforward control method according to claim 7, characterized in that: When the operating mode is the step-down mode, outputting a corresponding pulse width modulation signal based on the current operating mode includes: Obtaining a current input voltage sampling value and a previous input voltage sampling value, and determining a corresponding voltage ratio according to the current input voltage sampling value and the previous input voltage sampling value; Obtaining an initial first duty cycle corresponding to the pulse width modulation signal corresponding to the last input voltage sampling value; Determining the first duty cycle after feed-forward compensation corresponding to the voltage ratio and the initial first duty cycle; The pulse width modulation signal whose duty cycles are respectively the first duty cycle after feedforward compensation and zero is output.

9. The feedforward control method according to claim 7, characterized in that: When the operating mode is the boost mode, outputting a corresponding pulse width modulation signal based on the current operating mode includes: Obtaining a current input voltage sampling value and a previous input voltage sampling value, and determining a corresponding voltage ratio according to the current input voltage sampling value and the previous input voltage sampling value; Obtaining an initial second duty cycle corresponding to the pulse width modulation signal corresponding to the last input voltage sampling value, and determining a corresponding initial duty cycle difference according to the standard value and the initial second duty cycle; Determining the second duty cycle after feed-forward compensation corresponding to the difference between the standard value, the voltage ratio, and the initial duty cycle; The pulse width modulation signal having a duty cycle of the standard value and the second duty cycle after feedforward compensation is output.

10. The feedforward control method according to claim 7, characterized in that: When the operating mode is the buck-boost mode, outputting a corresponding pulse width modulation signal based on the current operating mode includes: Obtaining a current input voltage sampling value and a previous input voltage sampling value, and determining a corresponding voltage ratio according to the current input voltage sampling value and the previous input voltage sampling value; Obtaining an initial first duty cycle and an initial second duty cycle corresponding to the pulse width modulation signal corresponding to the last input voltage sampling value, and determining a corresponding initial duty cycle difference according to the standard value and the initial second duty cycle; Determining the first duty cycle after feed-forward compensation corresponding to the voltage ratio and the initial first duty cycle; Determining the second duty cycle after feed-forward compensation corresponding to the difference between the standard value, the voltage ratio, and the initial duty cycle; In the first half cycle, the pulse width modulation signal having the duty cycles being the first duty cycle after feedforward compensation and zero is output; In the second half cycle, the pulse width modulation signal having a duty cycle of the standard value and the second duty cycle after feedforward compensation is output.

11. An electronic device, characterized in that: include: memory for storing computer programs; A processor, configured to execute the computer program to implement the steps of the feedforward control method according to any one of claims 7 to 10.

12. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the feedforward control method according to any one of claims 7 to 10 are implemented.

13. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the feedforward control method according to any one of claims 7 to 10 are implemented.

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