Switching transistor drive voltage control circuit, method and power converter

Abstract

The present application relates to a switching tube drive voltage control circuit, method, and power converter. The switching tube drive voltage control circuit in one aspect is used to connect to each switching tube in the power converter, and includes: a sampling circuit, a first feedback circuit, a power supply circuit, and a drive circuit. Among them, the first sampling circuit is used to sample the AC side voltage of the power conversion circuit to obtain a target sampling voltage; the first feedback circuit is used to process the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage; the power supply circuit is used to output a target power supply voltage based on the target feedback voltage; the drive circuit is used to output a target drive voltage based on the target power supply voltage to drive the conduction of the switching tube. Using the above-mentioned switching tube drive voltage control circuit can improve the conversion efficiency of the power converter.

Description

Technical Field

[0001] The present application relates to the technical field of power conversion, and in particular, to a switching tube drive voltage control circuit, method, and power converter. Background Art

[0002] A power converter is a power conversion device used to convert electrical energy from one form to another to achieve energy transmission and control under different power requirements. The working principle of the power converter is to make the switching tube continuously "turn on" and "turn off" through a control circuit. When the switching tube performs pulse modulation on the input voltage, power conversion such as DC-AC voltage conversion or DC-DC voltage conversion is achieved.

[0003] In the related art, the magnitude of the drive voltage for turning on the gate of the switching tube is fixed, resulting in a low conversion efficiency of the power converter. Summary of the Invention

[0004] Based on this, it is necessary to provide a switching tube drive voltage control circuit, method, and power converter that can improve the conversion efficiency of the power converter for the above technical problems.

[0005] In a first aspect, the present application provides a switching tube drive voltage control circuit for connecting to each switching tube in a power converter. The switching tube drive voltage control circuit includes: a first sampling circuit, a first feedback circuit, a power supply circuit, and a drive circuit, where,

[0006] The first sampling circuit is used to sample the AC-side voltage of the power conversion circuit to obtain a target sampling voltage;

[0007] The first feedback circuit is used to process the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage, where the first mapping relationship includes that the magnitude of the feedback voltage corresponding to the first sampling voltage is not greater than the magnitude of the feedback voltage corresponding to the second sampling voltage, and the magnitude of the first sampling voltage is greater than the magnitude of the second sampling voltage;

[0008] The power supply circuit is used to output a target power supply voltage based on the target feedback voltage, and the relationship between the magnitude of the target power supply voltage and the magnitude of the target feedback voltage is negatively correlated;

[0009] The drive circuit is used to output a target drive voltage based on the target power supply voltage to drive the conduction of the switching tube, where the switching frequency of the switching tube changes with the magnitude of the AC-side voltage.

[0010] In one of the embodiments, the first feedback circuit includes:

[0011] The first microcontroller, the input end of the first microcontroller is connected to the output end of the sampling circuit, and the output end of the first microcontroller is connected to the feedback input end of the power supply circuit.

[0012] In one of the embodiments, the output end of the first microcontroller includes the digital-to-analog output end of the first microcontroller;

[0013] The first microcontroller is configured to process based on the target sampling voltage according to the first mapping relationship, and output the target feedback voltage through the digital-to-analog output end.

[0014] In one of the embodiments, the output end of the first microcontroller includes a duty cycle output end; the feedback circuit further includes a first filter circuit, the input end of the first filter circuit is connected to the duty cycle output end, and the output end of the first filter circuit is connected to the feedback input end of the power supply circuit;

[0015] The first microcontroller is configured to process based on the target sampling voltage according to the first mapping relationship, and output the first duty cycle voltage through the duty cycle output end;

[0016] The first filter circuit is configured to filter the first duty cycle voltage to obtain the target feedback voltage.

[0017] In one of the embodiments, the first mapping relationship includes a linear relationship between the amplitude of the feedback voltage and the amplitude of the sampling voltage.

[0018] In one of the embodiments, the first mapping relationship includes a non-linear relationship between the amplitude of the feedback voltage and the amplitude of the sampling voltage.

[0019] In one of the embodiments, the first feedback circuit includes a rectifying circuit and a second filter circuit, wherein,

[0020] The rectifying circuit is configured to rectify and phase-shift the target sampling voltage to obtain a rectified voltage;

[0021] The second filter circuit is configured to filter and amplify the rectified voltage to obtain the target feedback voltage.

[0022] In one of the embodiments, the power supply circuit includes an auxiliary power chip, a first resistor, a second resistor, and a third resistor; wherein,

[0023] The output end of the auxiliary power chip is connected to the first end of the first resistor, and the feedback input end of the auxiliary power chip is connected to the second end of the first resistor, the first end of the second resistor, and the first end of the third resistor;

[0024] The second end of the second resistor is grounded;

[0025] The second end of the third resistor is connected to the output end of the feedback circuit.

[0026] In a second aspect, a switching transistor drive voltage control circuit provided by the present application is used to connect to each switching transistor in a power conversion circuit. The switching transistor drive voltage control circuit includes: a second feedback circuit, a power supply circuit, and a drive circuit. Among them,

[0027] The second feedback circuit is configured to obtain the target switching frequency of the switching transistor, and process it according to a second mapping relationship based on the target switching frequency to obtain a target feedback voltage. The second mapping relationship includes that the amplitude of the feedback voltage corresponding to the first switching frequency is not less than the amplitude of the feedback voltage corresponding to the second switching frequency, and the first switching frequency is greater than the second switching frequency;

[0028] The power supply circuit is configured to output a target power supply voltage based on the target feedback voltage. The relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated;

[0029] The drive circuit is configured to output a target drive voltage based on the target power supply voltage to drive the conduction of the switching transistor. Among them, the switching frequency of the switching transistor changes with the magnitude of the voltage on the AC side of the power conversion circuit.

[0030] In one of the embodiments, the second feedback circuit includes a programmable logic device and a third filter circuit. The output terminal of the third filter circuit is connected to the digital output terminal of the programmable logic device, and the output terminal of the third filter circuit is connected to the feedback input terminal of the power supply circuit; among them,

[0031] The programmable logic device is configured to obtain the target switching frequency, process it according to the second mapping relationship, and output a second duty cycle voltage through the digital output terminal;

[0032] The third filter circuit is configured to filter the second duty cycle voltage to obtain the target feedback voltage.

[0033] In a third aspect, the present application further provides a method for controlling the drive voltage of a switching transistor, including:

[0034] Obtaining a target sampling voltage corresponding to the voltage on the AC side of the power conversion circuit;

[0035] Performing a mapping process on the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage. The first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage;

[0036] Among them, the target feedback voltage is used to determine a target drive voltage for driving the conduction of the switching transistor based on the target feedback voltage. The relationship between the amplitude of the target drive voltage and the amplitude of the target feedback voltage is negatively correlated, and the switching frequency of the switching transistor changes with the magnitude of the voltage on the AC side.

[0037] In a fourth aspect, the present application further provides a method for controlling the driving voltage of a switching tube, including:

[0038] Obtaining the target switching frequency of the switching tube of the power conversion circuit;

[0039] Processing the target switching frequency according to a second mapping relationship to obtain a target feedback voltage, where the second mapping relationship includes that the amplitude of the feedback voltage corresponding to a first switching frequency is not less than the amplitude of the feedback voltage corresponding to a second switching frequency, and the first switching frequency is greater than the second switching frequency;

[0040] wherein, the target feedback voltage is used to determine a target driving voltage for driving the switching tube to conduct, the relationship between the amplitude of the target driving voltage and the amplitude of the target feedback voltage is negatively correlated, and the switching frequency of the switching tube changes with the magnitude of the voltage on the AC side of the power conversion circuit.

[0041] In a fifth aspect, the present application further provides a power converter, which includes the switching tube driving voltage control circuit of the first aspect or the second aspect and a power conversion circuit;

[0042] wherein, the switching tube driving voltage control circuit is connected to the driving ends of the switching tubes in the power conversion circuit.

[0043] The switch tube drive voltage control circuit, method, and power converter provided above. The switch tube drive voltage control circuit in one aspect is used to connect to each switch tube in the power conversion circuit and includes: a first sampling circuit, a first feedback circuit, a power supply circuit, and a drive circuit. Among them, the first sampling circuit is used to sample the AC-side voltage of the power conversion circuit to obtain a target sampling voltage; the first feedback circuit is used to process the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage. The first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage; the power supply circuit is used to output a target power supply voltage based on the target feedback voltage, and the relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated; the drive circuit is used to output a target drive voltage based on the target power supply voltage to drive the conduction of the switch tube. The switching frequency of the switch tube changes with the amplitude of the AC-side voltage. In this way, by sampling the AC-side voltage of the power conversion circuit and performing the first processing through the first feedback circuit, a feedback voltage that is overall negatively correlated with the first sampling voltage is obtained, and then the power supply circuit with the feedback voltage control function is used to perform the second processing based on the target feedback voltage to obtain a target power supply voltage that is negatively correlated with the target feedback voltage. In this way, a positive correlation relationship is established between the drive circuit and the amplitude of the AC-side voltage of the power conversion circuit through the first sampling circuit, the first feedback circuit, and the power supply circuit, so that the target drive voltage output by the drive circuit for driving the switch tube can dynamically adjust positively correlated with the amplitude of the AC-side voltage, dynamically reduce the drive loss and conduction loss, and improve the conversion efficiency of the power converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 It is a structural block diagram of a switch drive voltage control circuit in an embodiment;

[0046] Figure 2 It is a structural block diagram of a switch drive voltage control circuit in another embodiment;

[0047] Figure 3 It is a structural block diagram of a switch drive voltage control circuit in another embodiment;

[0048] Figure 4Exemplary schematic diagram of voltage waveforms of the AC side voltage and the driving voltage in an embodiment;

[0049] Figure 5 Exemplary schematic diagram of voltage waveforms of the AC side voltage, the feedback voltage, and the driving voltage in an embodiment;

[0050] Figure 6 Structural block diagram of a switch driving voltage control circuit in another embodiment;

[0051] Figure 7 Structural block diagram of a switch driving voltage control circuit in another embodiment;

[0052] Figure 8 Structural block diagram of a switch driving voltage control circuit in another embodiment;

[0053] Figure 9 Flow schematic diagram of a switch driving voltage control method in an embodiment;

[0054] Figure 10 Flow schematic diagram of a switch driving voltage control method in another embodiment;

[0055] Figure 11 Internal structure diagram of a computer device in an embodiment. Detailed implementation manners

[0056] In order to make the objectives, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs. The terms used in the specification of the present application herein are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0058] It can be understood that the terms "first", "second", etc. used in the present application can be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present application, the first resistor can be called the second resistor, and similarly, the second resistor can be called the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0059] It can be understood that in the following embodiments, "connection", if there is an electrical signal or data transmission between the connected circuits, modules, units, etc., should be understood as "electrical connection", "communication connection", etc.

[0060] It can be understood that the term "based on" used in this application is used to describe one or more factors that affect a determination, and does not exclude other factors that may affect the determination. For example, the phrase "determining A based on B" means that the determination of A can be completely based on or at least partially based on factor B, that is, B is a factor affecting the determination of A, but does not exclude that the determination of A is also based on C.

[0061] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that terms such as "comprising" or "having" specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0062] The switching drive voltage control circuit provided by the embodiment of this application is used in a power converter in which the switching tube is actively driven. Exemplarily, the power converter is a DC-AC converter adopting a dual active bridge (DAB for short) topology. Among them, the DAB DC-AC converter is a power conversion topology structure with a dual active bridge, including eight power tubes, of which four switching tubes form a full-bridge circuit on the DC side, and the other four switching tubes form a half-bridge circuit on the AC side.

[0063] Among them, the switching tube can also be called a power tube; the switching tube involved in the embodiment of this application is a switching tube that is turned on by voltage drive, including but not limited to MOS tubes (Metal-Oxide-Semiconductor Field-Effect Transistor) and IGBTs (Insulated Gate Bipolar Transistor).

[0064] First, the principle on which the switching tube drive voltage control circuit provided by this embodiment is based will be introduced to facilitate a clear understanding of this solution.

[0065] Taking a MOS transistor as an example, when the gate drive voltage reaches the turn-on threshold of the MOS transistor, the MOS transistor can be turned on. Among them, within the tolerance range of the MOS transistor, the higher the gate drive voltage, the smaller the on-resistance of the MOS transistor, and the corresponding on-loss of the MOS transistor is smaller. However, a higher drive voltage does not require the drive circuit of the MOS transistor to provide more energy, and the corresponding drive loss of the MOS transistor is larger. Through a large number of experimental studies, the applicant found that the on-loss of the MOS transistor is more obvious when the output power of the power converter is larger (i.e., the output current), and the drive loss is more obvious when the switching frequency is higher.

[0066] In a power converter with an active drive switch tube, the control logic of the power converter determines that the larger the amplitude of the AC-side voltage, the larger the instantaneous power of the power converter, and the smaller the switching frequency of the switch tube; among them, when the AC-side voltage is near the peak point, the output power of the power converter is relatively high, and the switching frequency of the MOS transistor is relatively low. When the AC-side voltage is near the zero-crossing point, the output power of the power converter is relatively low, and the switching frequency of the MOS transistor is relatively high; taking a micro-inverter based on the DAB topology in the grid-connected working state as an example, near the peak point of the grid voltage, the switching frequencies of the MOS transistors in the micro-inverter are relatively low, and the output power of the power converter is high. Near the zero-crossing point of the grid voltage, the switching frequencies of the MOS transistors in the inverter are relatively high, and the output power of the power converter is low; that is, within one AC cycle, the switching frequency of the MOS transistor is negatively correlated with the absolute value of the AC-side voltage, and the working current of the MOS transistor is positively correlated with the absolute value of the AC-side voltage.

[0067] Based on this, the present application provides a switch tube drive voltage control circuit through the following embodiments. When the amplitude of the AC-side voltage is relatively high, the drive voltage is increased. At this time, the switching frequency of the MOS transistor is relatively low, the drive loss is not obvious, and the conduction current is relatively high, so the conduction loss is more obvious. Considering that the higher the drive voltage, the smaller the conduction loss and the larger the drive loss, the overall loss of the MOS transistor is relatively small at this time, and the efficiency of the power converter is relatively high; when the amplitude of the AC-side voltage is relatively low, the drive voltage is decreased. At this time, the switching frequency of the MOS transistor is relatively high, the drive loss is more obvious, and the conduction current is relatively small, so the conduction loss is not obvious. Considering the characteristics that the lower the drive voltage, the larger the conduction loss and the smaller the drive loss, the overall loss of the MOS transistor is relatively small at this time, and the efficiency of the power converter is relatively high; in this way, the conduction loss and drive loss of the MOS transistor are dynamically reduced, the overall loss of the power conversion circuit is reduced, and finally the efficiency of the power converter is improved.

[0068] In an exemplary embodiment, the provided switch tube drive voltage control circuit 100 is used to connect to each switch tube in the power conversion circuit. Please refer to Figure 1 and the switch tube drive voltage control circuit 100 includes a first sampling circuit 110, a first feedback circuit 120, a power supply circuit 130, and a drive circuit 140.

[0069] Among them, the first sampling circuit 110 is used to sample the AC-side voltage of the power conversion circuit to obtain a target sampling voltage.

[0070] Exemplarily, the AC side of the power converter can be connected to the power grid, and the AC-side voltage is the grid voltage; exemplarily, the AC side of the power converter can also be connected to an AC load, and the AC-side voltage is the load voltage.

[0071] Exemplarily, the first sampling circuit 110 can be a current transformer and a resistor, which are used to sample the AC-side current according to a ratio of 1:N, and then convert it into a target sampling voltage through the resistor. Where N is the turns ratio of the current transformer. Additionally exemplarily, the first sampling circuit 110 can include a voltage sampling chip.

[0072] The first feedback circuit 120 is used to process the target sampling voltage according to the first mapping relationship to obtain a target feedback voltage. Among them, the first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage; the power supply circuit 130 is used to output a target power supply voltage based on the target feedback voltage; the relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated. The drive circuit 140 is used to output a target drive voltage based on the target power supply voltage to drive the switch tube to conduct. Among them, the switching frequency of the switch tube changes with the amplitude of the AC-side voltage. Specifically, the greater the amplitude of the AC-side voltage, the greater the instantaneous power of the power conversion circuit, and the smaller the switching frequency. Among them, the drive circuit 140 is connected to the power conversion circuit 200 in the power converter to provide a drive voltage for each switch tube in the power conversion circuit 200. Exemplarily, the power conversion circuit 200 is a DAB topology circuit.

[0073] Exemplarily, the drive circuit 140 can be connected to a programmable logic device in the power converter to control the switching frequency of each switch tube.

[0074] Among them, the input end of the first feedback circuit 120 is connected to the first sampling circuit 110, and the output end of the first feedback circuit 120 is connected to the feedback input end of the power supply circuit 130, so that the power supply circuit 130 can adjust the output voltage of the power supply circuit 130 based on the output of the first feedback circuit 120.

[0075] Among them, the target feedback voltage is obtained by processing the target sampling voltage according to the first mapping relationship. The change trend between the target feedback voltage and the target sampling voltage is opposite, that is, the larger the amplitude of the sampling voltage, the smaller the amplitude of the feedback voltage. The relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated, that is, the smaller the target feedback voltage, the larger the target power supply voltage. In this way, through the first feedback circuit 120 and the power supply circuit 130, the amplitude of the target power supply voltage input to the drive circuit 140 is positively correlated with the amplitude of the target sampling voltage, so that the amplitude of the target drive voltage output by the drive circuit 140 to the switching tube is positively correlated with the amplitude of the target sampling voltage, realizing that when the amplitude of the AC-side voltage is large, the drive voltage of the switching tube is large, and when the amplitude of the AC-side voltage is small, the drive voltage of the switching tube is low, dynamically reducing the conduction loss and drive loss of the MOS tube.

[0076] Among them, the first sampling voltage and the second sampling voltage refer to any two voltages with different amplitudes that the first sampling circuit 110 can output. The first sampling voltage refers to the sampling voltage with a larger amplitude, and the second sampling voltage refers to the sampling voltage with a smaller amplitude. The first sampling voltage and the second sampling voltage in the embodiments of the present application are used to illustrate the mapping relationship between the sampling voltage and the feedback voltage included in the first mapping relationship.

[0077] In a possible implementation manner, the first mapping relationship includes a linear relationship between the amplitude of the feedback voltage and the amplitude of the sampling voltage. In this implementation manner, the first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is less than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage, that is, the first mapping relationship means that the larger the sampling voltage, the smaller the amplitude of the feedback voltage.

[0078] Exemplarily, the first mapping relationship is V o =A - B*|V ac |, where V o represents the feedback voltage, V ac represents the sampling voltage, and A and B are preset mapping parameters. Exemplarily, A = 2.35 and B = 0.00163; in this example, the mapping parameters A and B are debugged by the applicant according to the hardware parameters of the power supply circuit, the electrical characteristics of the switching tube, and the actual test results in the test, and are not used as limitations on the mapping parameters. It can be understood that those skilled in the art can debug and determine the mapping parameters according to specific implementation situations including but not limited to the hardware parameters of the power supply circuit and / or the electrical characteristics of the switching tube.

[0079] In a possible implementation, the first mapping relationship includes a non-linear relationship between the amplitude of the feedback voltage and the amplitude of the sampling voltage. In this implementation, the amplitude of the sampling voltage is divided into multiple amplitude intervals, and each amplitude interval corresponds to a different feedback voltage. The sampling voltages within the same amplitude interval correspond to the same feedback voltage; overall, the sampling voltage and the feedback voltage are negatively correlated. Exemplarily, the first mapping relationship includes a piecewise function. Additionally exemplarily, the first mapping relationship includes a list mapping relationship.

[0080] In a possible implementation, the first feedback circuit 120 is implemented using a pure hardware circuit. In another possible implementation, the first feedback circuit 120 includes a first microcontroller 121, that is, it is implemented through a combination of software and hardware. Among them, the full English name of the microcontroller is Microcontroller Unit, abbreviated as MCU.

[0081] Among them, the power supply circuit 130 adjusts the output power supply voltage according to the input feedback voltage. Among them, the larger the amplitude of the input feedback voltage, the smaller the amplitude of the output power supply voltage, and the smaller the amplitude of the input feedback voltage, the smaller the amplitude of the output power supply voltage. This power supply voltage refers to the power supply voltage input to the drive circuit 140.

[0082] In a possible implementation, please refer to Figure 2 and Figure 3 , the power supply circuit 130 includes an auxiliary power supply chip 131 with voltage feedback characteristics and the peripheral circuit corresponding to this auxiliary power supply chip 131. Among them, as shown in Figure 2 and Figure 3 , V out is the power supply voltage output by the power supply circuit 130, V o refers to the feedback voltage, and FB refers to the feedback pin of the auxiliary power supply chip 131. Please refer to Figure 2 and Figure 3 , the peripheral circuit includes a first resistor R1, a second resistor R2, and a third resistor R FB . Among them, the output terminal of the auxiliary power supply chip 131 is connected to the first end of the first resistor R1, the feedback input terminal of the auxiliary power supply chip 131 is connected to the second end of the first resistor R1, the first end of the second resistor R2, and the first end of the third resistor R FB , the second end of the second resistor R2 is grounded, and the second end of the third resistor R3 is connected to the output terminal of the first feedback circuit 120.

[0083] The power supply voltage V out output by the power supply circuit 130 is regulated by the voltage of its feedback pin and can provide a gate drive voltage for the MOS transistor through the drive circuit 140.

[0084] Exemplarily, the auxiliary source chip 131 is a BUCK (step-down) power chip.

[0085] The switching transistor driving voltage control circuit 100 provided in the above embodiment is used to be connected to each switching transistor in the power converter, and includes: a first sampling circuit 110, a first feedback circuit 120, a power supply circuit 130, and a driving circuit 140. Among them, the first sampling circuit 110 is used to sample the AC-side voltage of the power conversion circuit to obtain a target sampling voltage; the first feedback circuit 120 is used to process the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage. The first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage; the power supply circuit 130 is used to output a target power supply voltage based on the target feedback voltage, and the relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated; the driving circuit 140 is used to output a target driving voltage based on the target power supply voltage to drive the conduction of the switching transistor. The switching frequency of the switching transistor changes with the amplitude of the AC-side voltage. In this way, by sampling the AC-side voltage of the power conversion circuit, the first feedback circuit 120 performs the first processing to obtain a feedback voltage that is overall negatively correlated with the sampling voltage, and then the power supply circuit 130 with the feedback voltage control function performs the second processing based on the target feedback voltage to obtain a target power supply voltage that is negatively correlated with the target feedback voltage. In this way, a positive correlation relationship is established between the driving voltage and the amplitude of the AC-side voltage of the power conversion circuit through the first sampling circuit 110, the first feedback circuit 120, and the power supply circuit 130, so that the target driving voltage output by the driving circuit 140 for driving the switching transistor can dynamically adjust positively correlated with the amplitude of the AC-side voltage, dynamically reducing the driving loss and conduction loss, and improving the conversion efficiency of the power converter.

[0086] Exemplarily, applying the switching transistor driving voltage control circuit 100 provided in the above embodiment to the grid-connected operation process of a micro-inverter based on the DAB topology structure, please refer to Figure 4 ., at the peak point A of the grid voltage, the switching frequency of the switching transistor is low at this time, the output current is large, and the conduction loss is dominant. The driving voltage is increased to reduce the conduction loss; at the zero-crossing point B of the grid voltage, the switching frequency of the MOS transistor is high at this time, the output current of the micro-inverter is small, and the driving loss is dominant. The driving voltage is reduced to reduce the driving loss.

[0087] Please refer to Figure 5 ., which is an exemplary schematic diagram of the change trends among the AC-side voltage, the feedback voltage, and the driving voltage. When the first mapping relationship is a non-linear relationship, the waveforms of the feedback voltage and the driving voltage can be stepped, and the change trend of the feedback voltage is opposite to the change trend of the amplitude of the AC-side voltage.

[0088] In an exemplary embodiment, please refer to Figure 2 and Figure 3 , based on the embodiment shown in Figure 1 , the first feedback circuit 120 in the switching transistor drive voltage control circuit 100 provided includes a first microcontroller 121. Among them, the input end of the first microcontroller 121 is connected to the output end of the first sampling circuit 110, and the output end of the first microcontroller 121 is connected to the feedback input end of the power supply circuit 130.

[0089] In a possible implementation manner, please refer to Figure 2 , the output end of the first microcontroller 121 includes the digital-to-analog output end of the first microcontroller 121, that is, the DA (Digital-to-Analog) pin. In this implementation manner, the first microcontroller 121 is configured to process based on the target sampling voltage according to the first mapping relationship, and output the target feedback voltage through the digital-to-analog output end. Among them, the target feedback voltage is an analog signal.

[0090] In this implementation manner, using the DA pin on the first microcontroller 121 to directly output the target feedback voltage in the form of an analog signal, without an additional filtering circuit, the hardware cost is low, and the circuit topology is simple.

[0091] In a possible implementation manner, please refer to Figure 3 , the output end of the first microcontroller 121 includes a duty cycle output end, and the first feedback circuit 120 further includes a first filtering circuit. Among them, the input end of the first filtering circuit is connected to the duty cycle output end, and the output end of the first filtering circuit is connected to the input end of the first feedback circuit 120. Among them, the first microcontroller 121 is configured to process based on the target sampling voltage according to the first mapping relationship, and output the first duty cycle voltage through the duty cycle output end; the first filtering circuit is configured to filter the first duty cycle voltage to obtain the target feedback voltage.

[0092] Exemplarily, please refer to Figure 3 , the first filtering circuit includes an RC (resistor-capacitor) filtering circuit. As Figure 3 shown, the first filtering circuit includes a resistor R3 and a capacitor C1.

[0093] Exemplarily, the duty cycle output end of the first microcontroller 121 can be the general purpose input output (GPIO) pin of the first microcontroller 121: Again exemplarily, the duty cycle output end of the first microcontroller 121 can be the PWM (Pulse Width Modulator) output pin of the first microcontroller 121, as Figure 3 shown.

[0094] Among them, the first duty cycle voltage output by the duty cycle output terminal is in the form of a PWM wave, that is, in the form of a digital signal, and is converted into a target feedback voltage in the form of an analog signal through the first filter circuit.

[0095] In this embodiment, the duty cycle output terminal of the first microcontroller 121 first outputs the first duty cycle voltage in the form of a digital signal, and then filters it into the target feedback voltage in the analog form through the first filter circuit, which can reduce the resource occupation of the first microcontroller 121 and avoid the shortage of DA pin resources on the first microcontroller 121. Further, the switching transistor drive voltage control circuit 100 provided in this embodiment can be implemented using a first microcontroller 121 without a DA pin, improving the flexibility of the scheme application.

[0096] The switching transistor drive voltage control circuit 100 provided in the above embodiment implements the first feedback circuit 120 based on the first microcontroller 121. The first microcontroller 121 can read the real-time state of the voltage on the AC side of the power converter through the first sampling circuit 110, connect to the feedback input terminal of the power supply circuit 130, and inject a feedback voltage into the power supply circuit 130 to adjust the power supply voltage output by the power supply circuit 130. In this embodiment, the mapping from the sampled voltage to the feedback voltage is implemented by combining the first microcontroller 121 with software, and the accuracy is relatively high. The specific parameters in the first mapping relationship can be flexibly adjusted according to the hardware parameters of the switching transistors in the power conversion part of the power converter or the corresponding hardware parameters of the power supply circuit 130. The switching transistor drive voltage control circuit 100 provided in this embodiment has good scalability.

[0097] In a possible implementation manner of this embodiment, the target drive voltage can be automatically adjusted by the first microcontroller 121 to find the highest efficiency point. Exemplarily, based on the waveform of the target power supply voltage currently output by the drive circuit 140, by setting a corresponding closed-loop control algorithm in the first microcontroller 121, the current efficiency of the power converter is calculated, so that the drive voltage is within the safe range and the optimal target drive voltage is found by itself; for example, the Figure 4 maximum amplitude and minimum amplitude of the drive voltage waveform can be adjusted.

[0098] In a possible implementation manner of this embodiment, the first mapping relationship includes a first mapping relationship A and a first mapping relationship B, which respectively correspond to different switching tubes. It can be understood that the mapping parameters in the first mapping relationship A and the first mapping relationship B are determined based on the electrical characteristics of different switching tubes; the first feedback circuit 120 based on the first microcontroller 121 can determine the mapping relationship that needs to be used currently from the first mapping relationship A and the first mapping relationship B based on the characteristics of the AC-side voltage; or, the first feedback circuit 120 based on the first microcontroller 121 can switch the mapping relationship to be used currently in response to the user's input; further, the first mapping relationship can include multiple different first mapping relationships, and the first microcontroller 121 is used to switch the required mapping relationship during specific use, improving the scalability of the switching tube drive voltage circuit.

[0099] In a possible implementation manner of this embodiment, the first microcontroller 121 is further configured to, in the process of processing the target sampling voltage according to the first mapping relationship to obtain the target feedback voltage, specifically configured to obtain the initial feedback voltage based on the target sampling voltage and the first mapping relationship. If the amplitude of the initial feedback voltage is greater than or equal to the preset feedback voltage threshold, the initial feedback voltage is used as the target feedback voltage. If the initial feedback voltage is greater than the preset feedback voltage threshold, the target feedback voltage is obtained based on the preset feedback voltage threshold. In this way, when the AC-side voltage increases abnormally, such as when the grid voltage has a high penetration or cumulative surge, the target feedback voltage output by the first feedback circuit 120 will not be too small, and the target power supply voltage output by the power supply circuit 130 will not be too large, which is equivalent to setting an upper limit for the drive voltage of the switching tube and improving the safety of the circuit operation.

[0100] In an exemplary embodiment, please refer to Figure 6 , the first feedback circuit 120 in the provided switching drive voltage control circuit includes a rectification circuit 122 and a second filtering circuit 123. Among them, the rectification circuit 122 is configured to rectify and phase-shift the target sampling voltage to obtain the rectified voltage; the second filtering circuit 123 is configured to filter and amplify the rectified voltage to obtain the target feedback voltage.

[0101] Exemplarily, the rectification circuit 122 includes a full-bridge rectification circuit and a phase-shift circuit composed of four diodes.

[0102] Among them, the full-bridge rectification circuit rectifies the target sampling voltage to obtain a waveform with the same amplitude change as the AC-side voltage. In order to obtain the rectified voltage with a change trend opposite to that of the AC-side voltage, the phase-shift circuit shifts the phase of the rectified voltage by 180°, or an integer multiple of 180°.

[0103] Exemplarily, the second filtering circuit 123 includes an RC filtering circuit and an amplifying circuit. The RC filtering circuit filters and smooths the rectified voltage to obtain the filtered voltage of the analog signal waveform. The amplifying circuit amplifies the filtered voltage to adjust the amplitude of the filtered voltage and obtain the target feedback voltage determined by the first mapping relationship. Among them, the amplification factor of the amplifying circuit can be greater than 1 or less than 1. Exemplarily, the amplification factor can be determined according to the electrical parameter characteristics of the auxiliary power chip, the rectifying circuit 122, and the switching transistor used in the power supply circuit 130.

[0104] In a possible implementation manner, in addition to the full-bridge rectifying circuit and the phase-shifting circuit, the rectifying circuit 122 further includes an isolation circuit. The input end of the isolation circuit is connected to the output end of the first sampling circuit 110, and the output end of the isolation circuit is connected to the full-bridge rectifying circuit. Exemplarily, the isolation circuit includes two inverters connected in sequence.

[0105] In this implementation manner, the adoption of the isolation circuit can prevent the relevant interference between the first sampling circuit 110 and the rectifying circuit 122 and improve the reliability of the operation of the switching drive voltage control circuit.

[0106] In an exemplary embodiment, the first feedback circuit 120 includes a buck circuit, a rectifying circuit, and a filtering circuit. The voltage amplitude on the AC side of the power converter is generally 0V - 390V, which is relatively large. In this embodiment, the sampled target AC voltage is first bucked by the buck circuit to obtain the bucked voltage, and then rectified, phase-shifted, and filtered.

[0107] In an exemplary embodiment, please refer to Figure 7 , a switching transistor drive voltage control circuit 300 is provided for connecting to each switching transistor in the power converter circuit 200. As Figure 7 shown, the switching transistor drive voltage control circuit 300 includes a second feedback circuit 310, a power supply circuit 130, and a drive circuit 140. It can be understood that the switching transistor drive voltage control circuit 300 provided in this embodiment adopts a different feedback circuit topology, the same power supply circuit topology, and drive circuit topology as the switching transistor drive voltage control circuit 300 provided in the foregoing embodiment.

[0108] Among them, the second feedback circuit 310 is configured to obtain the target switching frequency of the switching transistor, and process it according to the second mapping relationship based on the target switching frequency to obtain the target feedback voltage; the second mapping relationship includes that the amplitude of the feedback voltage corresponding to the first switching frequency is not less than the amplitude of the feedback voltage corresponding to the second switching frequency, and the first switching frequency is greater than the second switching frequency. Wherein, the switching frequency of the switching transistor changes with the amplitude of the AC-side voltage of the power conversion circuit. Specifically, the greater the amplitude of the AC-side voltage, the greater the instantaneous power of the power conversion circuit, and the smaller the switching frequency. The power supply circuit 130 is configured to output a target power supply voltage based on the target feedback voltage, and the relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated. The driving circuit 140 is configured to output a target driving voltage based on the target power supply voltage to drive the conduction of the switching transistor.

[0109] In a possible implementation manner, the second mapping relationship includes a linear relationship between the switching frequency and the amplitude of the sampling voltage. In this implementation manner, the second mapping relationship includes that the amplitude of the feedback voltage corresponding to the first switching frequency is greater than the amplitude of the feedback voltage corresponding to the second switching frequency, that is, the second mapping relationship means that the lower the switching frequency, the smaller the amplitude of the feedback voltage.

[0110] In a possible implementation manner, the second mapping relationship includes a non-linear relationship between the switching frequency and the amplitude of the sampling voltage. In this implementation manner, the switching frequencies are divided into multiple frequency intervals according to numerical values, and different feedback voltages correspond to different frequency intervals, and the switching frequencies within the same frequency interval correspond to the same feedback voltage. In this implementation manner, there is a situation where the switching frequency changes while the amplitude of the feedback voltage remains unchanged. Overall, the switching frequency and the feedback voltage show a positively correlated mapping relationship. Exemplarily, the second mapping relationship includes a piecewise function; and exemplarily, the second mapping relationship includes a list mapping relationship.

[0111] In the power conversion circuit 200 of this embodiment, the switching frequency of each switching tube varies with the amplitude of the AC-side voltage of the power conversion circuit. Among them, when the amplitude of the AC-side voltage is relatively large, the switching frequency of the switching tube is relatively low. For example, near the peak value of the AC-side voltage, the switching frequency of the switching tube is the lowest; when the amplitude of the AC-side voltage is relatively small, the switching frequency of the switching tube is relatively high. For example, near the zero-crossing point of the AC-side voltage, the switching frequency of the switching tube is the highest. Based on this, in this embodiment, the amplitude of the driving voltage of the switching tube is directly adjusted according to the switching frequency of the switching tube. That is, the second feedback circuit 310 directly obtains the switching frequency used to control the switching tube, and outputs a feedback voltage according to the switching frequency to adjust the power supply voltage output by the power supply circuit 130, so that the driving voltage output by the driving circuit 140 changes with the switching frequency of the switching tube. Among them, the switching frequency is first processed by the second feedback circuit 310 to obtain a feedback voltage that is positively correlated with the switching frequency, and then the power supply circuit 130 with a feedback voltage control function is used to perform a second processing based on the feedback voltage to obtain a power supply voltage that is negatively correlated with the feedback voltage. By establishing a negative correlation between the driving voltage and the switching frequency of the switching tube of the power conversion circuit through the second feedback circuit 310 and the power supply circuit 130, the target driving voltage used to drive the switching tube output by the driving circuit 140 can be dynamically adjusted negatively with the switching frequency of the switching tube, dynamically reducing the driving loss and conduction loss, and improving the conversion efficiency of the power converter.

[0112] In an exemplary embodiment, based on Figure 7 the embodiment shown, please refer to Figure 8 , the second feedback circuit includes a programmable logic device 311 and a third filter circuit; the output terminal of the third filter circuit is connected to the digital output terminal of the programmable logic device, and the output terminal of the third filter circuit is connected to the feedback input terminal of the power supply circuit 130.

[0113] Among them, the programmable logic device 311 is used to obtain the target switching frequency, and process it according to the second mapping relationship, and output the second duty cycle voltage through the digital output terminal. Among them, the programmable logic device 311 is also used to process according to the AC-side voltage of the power conversion circuit to obtain the switching frequency of the switching tube.

[0114] Exemplarily, the programmable logic device 311 is implemented by a CPLD (Complex Programmable Logic Device). Additionally exemplarily, the programmable logic device 311 is implemented by an FPGA (Field Programmable Gate Array).

[0115] In a possible implementation manner, please refer to Figure 8, the input end of the programmable logic device 311 is used to connect to the output end of the second microcontroller 410. The input end of the second microcontroller 410 is connected to the output end of the second sampling circuit 420. The input end of the second sampling circuit 420 is connected to the AC-side output end of the power conversion circuit 200 and is used to sample the AC-side voltage of the power conversion circuit 200. The second microcontroller 410 is used to process the AC-side voltage output by the second sampling circuit 420 and output the AC-side voltage in the form of a digital signal, so that the programmable logic device 311 can process the AC-side voltage in the form of a digital signal to obtain the switching frequency of the switching tube.

[0116] The third filtering circuit is used to filter the second duty ratio voltage to obtain the target feedback voltage. In a possible implementation manner, the topological structure of the third filtering circuit is the same as that of the first filtering circuit, which is a sampling RC filtering circuit. As Figure 8 shown, the third filtering circuit includes a resistor R4 and a capacitor C2. In this embodiment, the third filtering circuit converts the second duty ratio voltage output from the digital output end of the programmable logic device 311 into the target feedback voltage in the form of an analog signal.

[0117] In the switching tube driving voltage control circuit provided in the above embodiment, the second feedback circuit is implemented by using the programmable logic device 311 for calculating the switching frequency and the third filtering circuit, without separately setting a sampling circuit and a processing device for the second feedback circuit, simplifying the circuit structure and improving the processing efficiency of the second feedback circuit.

[0118] In an exemplary embodiment, the second feedback circuit 310 includes a third microcontroller, and the third microcontroller is used to obtain the switching frequency of the switching tube. Exemplarily, the third microcontroller is used to connect to the output end of the programmable logic device. In this embodiment, the programmable logic device is used to determine the switching frequency of the switching tube based on the AC-side voltage. The output end of the programmable logic device is connected to each switching tube in the power conversion circuit and to the input end of the third microcontroller.

[0119] Optionally, the output end of the third microcontroller includes a digital-to-analog output end, and the digital-to-analog output end of the third microcontroller is connected to the feedback input end of the power supply circuit 130. Wherein, the third microcontroller is used to process based on the target switching frequency according to the second mapping relationship and output the target feedback voltage through the digital-to-analog output end.

[0120] In a possible implementation manner of this embodiment, the third microcontroller and Figure 8 the second microcontroller in it are the same controller.

[0121] In an exemplary embodiment, a method for controlling the driving voltage of a switching tube is provided; in this embodiment, it is assumed that this method is used for Figures 2 to 3Taking the first microcontroller 121 as an example for illustration, it can be understood that the method provided in this embodiment can also be used in other controllers or computer devices connected to the power supply circuit 130 and the first sampling circuit 110. Please refer to Figure 9 , the method includes steps 902 to 902, where:

[0122] Step 902, obtaining a target sampling voltage corresponding to the AC side voltage of the power conversion circuit.

[0123] Exemplarily, a real-time sampling voltage corresponding to the AC side voltage of the power conversion circuit is obtained through the first sampling circuit 110 connected to the first microcontroller 121.

[0124] Step 904, performing a mapping process on the target sampling voltage according to the first mapping relationship to obtain a target feedback voltage.

[0125] Wherein, the first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage.

[0126] Wherein, the target feedback voltage is used to determine a target drive voltage for driving the switch tube to conduct. The relationship between the amplitude of the target drive voltage and the amplitude of the target feedback voltage is negatively correlated, and the switching frequency of the switch tube changes with the magnitude of the AC side voltage.

[0127] In an exemplary embodiment, based on Figure 9 the embodiment shown, this embodiment relates to the process of performing a mapping process on the target sampling voltage according to the first mapping relationship to obtain a target feedback voltage: processing the target sampling voltage according to the first mapping relationship to obtain the amplitude of the target feedback voltage; obtaining the first duty cycle voltage based on the amplitude of the target feedback voltage; and performing a filtering process on the first duty cycle voltage to obtain the target feedback voltage.

[0128] In an exemplary embodiment, a method for controlling the drive voltage of a switch tube is provided; this embodiment takes the method being used in Figure 8 the second feedback circuit 310 shown as an example for illustration. It can be understood that the method provided in this embodiment can also be used in other circuits or computer devices that can calculate or obtain the switching frequency of the switch tube and are connected to the power supply circuit. Please refer to Figure 10 , the method includes steps 1002 and 1004, where:

[0129] Step 1002, obtaining the target switching frequency of the switch tube of the power conversion circuit.

[0130] Exemplarily, the programmable logic device 311 performs calculation processing based on the AC side voltage to obtain the target switching frequency of the switching tube.

[0131] Step 1004, process the target switching frequency according to the second mapping relationship to obtain the target feedback voltage. The second mapping relationship includes that the amplitude of the feedback voltage corresponding to the first switching frequency is not less than the amplitude of the feedback voltage corresponding to the second switching frequency, and the first switching frequency is greater than the second switching frequency.

[0132] Wherein, the target feedback voltage is used to determine the target drive voltage for driving the switching tube to conduct. The relationship between the amplitude of the target drive voltage and the amplitude of the target feedback voltage is negatively correlated, and the switching frequency of the switching tube changes with the amplitude of the AC side voltage of the power conversion circuit.

[0133] Optionally, the programmable logic device 311 processes the target switching frequency according to the second mapping relationship to obtain the amplitude of the target feedback voltage, and obtains the second duty cycle voltage based on the amplitude of the target feedback voltage; the third filter circuit filters the second duty cycle voltage to obtain the target feedback voltage.

[0134] In an exemplary embodiment, a computer device is provided. The computer device can be the first microcontroller 121 in the power converter, or the programmable logic device 311 in the power converter, or the third microcontroller; its internal structure diagram can be as Figure 11 shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O), and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the data that needs to be stored and called when executing the pole welding control method. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, at least some steps of a switching tube drive voltage control method are implemented.

[0135] Those skilled in the art can understand, Figure 8The structure shown is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0136] In one embodiment, a computer device is further provided, including a memory and a processor. A computer program is stored in the memory, and when the processor executes the computer program, the steps in the above method embodiments are implemented.

[0137] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0138] In one embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0139] In an exemplary embodiment, a power converter is provided. The power converter includes the switch tube drive voltage control circuit 100 and the power conversion circuit 200 provided in the above embodiment, wherein the switch tube drive voltage control circuit 100 is connected to the drive ends of the switch tubes in the power conversion circuit 200.

[0140] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memories can include read-only memory (ROM), magnetic tapes, floppy disks, flash memories, optical memories, high-density embedded non-volatile memories, resistive random access memories (ReRAM), magnetoresistive random access memories (MRAM), ferroelectric random access memories (FRAM), phase change memories (PCM), graphene memories, etc. Volatile memories can include random access memory (RAM) or external cache memories, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided in the present application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided in the present application can be general-purpose processors, central processors, graphics processors, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0141] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0142] The above-described embodiments merely represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A switch tube driving voltage control circuit, characterized in that: The switch tube driving voltage control circuit is used to connect to each switch tube in the power conversion circuit, and the switch tube driving voltage control circuit includes: a first sampling circuit, a first feedback circuit, a power supply circuit and a drive circuit, wherein the first feedback circuit is respectively connected to the first sampling circuit and the power supply circuit, and the drive circuit is respectively connected to the power supply circuit and the power conversion circuit; The first sampling circuit is used to sample the AC side voltage of the power conversion circuit to obtain a target sampling voltage; The first feedback circuit is used to process the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage, wherein the first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage; The power supply circuit is used to output a target power supply voltage based on the target feedback voltage, and the relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated; The driving circuit is used to output a target driving voltage based on the target power supply voltage to drive the switch tube to be turned on, wherein the switching frequency of the switch tube varies with the amplitude of the AC side voltage.

2. The switch tube driving voltage control circuit according to claim 1, characterized in that: The first feedback circuit comprises: A first microcontroller, wherein an input end of the first microcontroller is connected to an output end of the first sampling circuit, and an output end of the first microcontroller is connected to a feedback input end of the power supply circuit.

3. The switch tube driving voltage control circuit according to claim 2, characterized in that: The output terminal of the first microcontroller includes a digital-to-analog output terminal of the first microcontroller; The first microcontroller is used to process the target sampling voltage according to the first mapping relationship and output the target feedback voltage through the digital-to-analog output terminal.

4. The switch tube driving voltage control circuit according to claim 2, characterized in that: The output end of the first microcontroller includes a duty cycle output end; the first feedback circuit also includes a first filter circuit, the input end of the first filter circuit is connected to the duty cycle output end, and the output end of the first filter circuit is connected to the feedback input end of the power supply circuit; The first microcontroller is used for processing the target sampled voltage according to the first mapping relationship, and outputting a first duty cycle voltage through the duty cycle output terminal; The first filtering circuit is used to filter the first duty cycle voltage to obtain the target feedback voltage.

5. The switch tube driving voltage control circuit according to claim 1, characterized in that: The first mapping relationship includes a linear relationship between the amplitude of the feedback voltage and the amplitude of the sampling voltage.

6. The switch tube driving voltage control circuit according to claim 1, characterized in that: The first mapping relationship includes a nonlinear relationship between the amplitude of the feedback voltage and the amplitude of the sampling voltage.

7. The switch tube driving voltage control circuit according to claim 1, characterized in that: The first feedback circuit includes a rectifier circuit and a second filter circuit, wherein: The rectifier circuit is used to perform rectification and phase shift processing on the target sampling voltage to obtain a rectified voltage; The second filtering circuit is used to filter and amplify the rectified voltage to obtain the target feedback voltage.

8. The switch tube driving voltage control circuit according to claim 1, characterized in that: The power supply circuit includes an auxiliary source chip, a first resistor, a second resistor and a third resistor; wherein, The output end of the auxiliary source chip is connected to the first end of the first resistor, and the feedback input end of the auxiliary source chip is connected to the second end of the first resistor, the first end of the second resistor, and the first end of the third resistor; The second end of the second resistor is grounded; The second end of the third resistor is connected to the output end of the first feedback circuit.

9. A switch tube driving voltage control circuit, characterized in that: The switch tube drive voltage control circuit is used to connect to each switch tube in the power conversion circuit, and the switch tube drive voltage control circuit includes: a second feedback circuit, a power supply circuit and a drive circuit, wherein: The second feedback circuit is used to obtain a target switching frequency of the switch tube, and process the target switching frequency according to a second mapping relationship to obtain a target feedback voltage, wherein the second mapping relationship includes that an amplitude of the feedback voltage corresponding to the first switching frequency is not less than an amplitude of the feedback voltage corresponding to the second switching frequency, and the first switching frequency is greater than the second switching frequency; The power supply circuit is used to output a target power supply voltage based on the target feedback voltage, and the relationship between the amplitude of the target power supply voltage and the amplitude of the target feedback voltage is negatively correlated; The driving circuit is used to output a target driving voltage based on the target power supply voltage to drive the switch tube to be turned on, wherein the switching frequency of the switch tube varies with the amplitude of the AC side voltage of the power conversion circuit.

10. The switch tube driving voltage control circuit according to claim 9, characterized in that: The second feedback circuit includes a programmable logic device and a third filter circuit, the output end of the third filter circuit is connected to the digital output end of the programmable logic device, and the output end of the third filter circuit is connected to the feedback input end of the power supply circuit; wherein, The programmable logic device is used to obtain the target switching frequency, and process according to the second mapping relationship based on the target switching frequency, and output a second duty cycle voltage through the digital output terminal; The third filtering circuit is used to filter the second duty cycle voltage to obtain the target feedback voltage.

11. A method for controlling a switch tube driving voltage, characterized in that: Applied to the switch tube driving voltage control circuit according to any one of claims 1 to 8, the method comprises: Obtaining a target sampling voltage corresponding to an AC side voltage of a power conversion circuit; Mapping the target sampling voltage according to a first mapping relationship to obtain a target feedback voltage, wherein the first mapping relationship includes that the amplitude of the feedback voltage corresponding to the first sampling voltage is not greater than the amplitude of the feedback voltage corresponding to the second sampling voltage, and the amplitude of the first sampling voltage is greater than the amplitude of the second sampling voltage; Among them, the target feedback voltage is used to determine the target driving voltage for driving the switching tube to conduct based on the target feedback voltage, the relationship between the amplitude of the target driving voltage and the amplitude of the target feedback voltage is negatively correlated, and the switching frequency of the switching tube changes with the amplitude of the AC side voltage.

12. A method for controlling a switch tube driving voltage, characterized in that: Applied to the switch tube drive voltage control circuit according to any one of claims 9 to 10, the method comprises: Obtaining a target switching frequency of a power conversion circuit switch tube; Processing the target switching frequency according to a second mapping relationship to obtain a target feedback voltage, wherein the second mapping relationship includes that an amplitude of the feedback voltage corresponding to the first switching frequency is not less than an amplitude of the feedback voltage corresponding to the second switching frequency, and the first switching frequency is greater than the second switching frequency; Among them, the target feedback voltage is used to determine the target driving voltage for driving the switching tube to conduct based on the target feedback voltage, the relationship between the amplitude of the target driving voltage and the amplitude of the target feedback voltage is negatively correlated, and the switching frequency of the switching tube changes with the amplitude of the AC side voltage of the power conversion circuit.

13. A power converter, characterized in that: The power converter comprises a switch tube driving voltage control circuit and a power conversion circuit as described in any one of claims 1 to 10; Wherein, the switch tube driving voltage control circuit is connected to the driving end of each switch tube in the power conversion circuit.

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