Driving circuit of inverter full-bridge circuit and inverter

Abstract

The utility model relates to a driving circuit of an inversion full-bridge circuit and an inverter, a power supply end of the driving circuit is connected with an external power supply through a voltage transformation module, and the driving circuit comprises a plurality of driving modules and a first circulation suppression module. The input end of each driving module is used for being connected with the secondary side of the voltage transformation module, the output end of each driving module is used for being correspondingly connected with the controlled end of each lower bridge arm power switch unit, the controlled end of each driving module is used for being connected with a driving control signal, and the voltage transformation module, the lower bridge arm power switch units and each driving module are in common ground connection; the first circulating current suppression module is connected between the voltage transformation module and the driving module. The driving circuit can avoid circulation crosstalk and reduce the turn-off loss of the power switch unit under the condition that the driving circuit of the inverter full-bridge circuit shares a power supply.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to a drive circuit and an inverter of an inverter full-bridge circuit. Background Art

[0002] In the field of power electronics, power switching units, such as insulated gate bipolar transistors (IGBTs), have the advantages of fast switching speed, low on-state voltage, and high reliability. Therefore, they are widely used in various power electronic devices, such as frequency converters, inverters, FACTS devices, etc.

[0003] When designing the drive circuit of the inverter full-bridge circuit, in order to ensure the stability and safety of the circuit, it is usually necessary to isolate the drive power supply of each power switch unit. However, in some cases, such as single board area limitation or reducing the complexity of the power supply, the drive power supply of the lower bridge arm power switch unit may use the same power supply. This method can effectively save single board space, reduce the number of isolation transformer modules, and reduce the difficulty of PCB layout and wiring.

[0004] However, the shared power supply method will cause the di / dt of a phase's power switch unit when it is turned on and off to generate an induced electromotive force with the parasitic inductance of the PCB wiring and copper busbar of the lower bridge arms of the other two phases, which will cause the grounding point level of the phase to change, breaking the balance of the grounding point potential of the lower tubes of the other two phases, resulting in circulating crosstalk, and further leading to increased turn-off losses of the power switch unit. Utility Model Content

[0005] Based on this, it is necessary to provide a driving circuit and an inverter for an inverter full-bridge circuit that can avoid circulating current crosstalk and reduce turn-off losses of a power switch unit.

[0006] In a first aspect, the present application provides a drive circuit for an inverter full-bridge circuit, wherein a power supply end of the drive circuit is connected to an external power supply through a transformer module, and the drive circuit comprises:

[0007] Multiple driving modules, the input end of each driving module is used to connect to the secondary side of the transformer module, the output end of each driving module is used to be connected to the controlled end of each lower bridge arm power switch unit respectively, the controlled end of the driving module is used to access the driving control signal, and the transformer module, the lower bridge arm power switch unit and each driving module are connected to a common ground;

[0008] The first circulating current suppression module is connected between the transformer module and the driving module.

[0009] In one embodiment, the first circulation suppression module includes:

[0010] A first circulating current suppression resistor, wherein a first end of the first circulating current suppression resistor is used to connect to a high potential end of a secondary side of the transformer module, and a second end of the first circulating current suppression resistor is connected to a first input end of the driving module;

[0011] A second circulating current suppression resistor, wherein the first end of the second circulating current suppression resistor is used to connect to the low potential end of the secondary side of the transformer module, and the second end of the second circulating current suppression resistor is connected to the second input end of the driving module.

[0012] In one embodiment, the driving circuit further includes:

[0013] A plurality of second circulating current suppression modules are provided, and each second circulating current suppression module is correspondingly connected between the ground terminal of each lower bridge arm power switch unit and the ground.

[0014] In one embodiment, the second circulating current suppression module includes a plurality of third circulating current suppression resistors connected in parallel, and each third circulating current suppression resistor is connected between the ground terminal of the corresponding lower bridge arm power switch unit and the ground.

[0015] In one embodiment, the driving module includes:

[0016] A filter unit, wherein a first input end of the filter unit is used to connect to a first end of a secondary side of the transformer module, and a second input end of the filter unit is used to connect to a second end of the secondary side of the transformer module;

[0017] A driving unit, wherein an input end of the driving unit is connected to an output end of the filtering unit, an output end of the driving unit is connected to a controlled end of the lower bridge arm power switch unit, and the controlled end of the driving unit is used to access a driving control signal;

[0018] The driving unit, the filtering unit, the voltage transformation module and the lower bridge arm power switch unit are connected to a common ground.

[0019] In one embodiment, the filter unit includes a plurality of first capacitors connected in parallel between a first input terminal of the filter unit and ground, and a plurality of second capacitors connected in parallel between a second input terminal of the filter unit and ground.

[0020] In one embodiment, the drive unit comprises:

[0021] A first switch tube, wherein the collector of the first switch tube is connected to the output end of the filter unit, and the base of the first switch tube is used to access the drive control signal;

[0022] The second switch tube has an emitter connected to the emitter of the first switch tube, a base of the second switch tube is used to access a driving control signal, and a collector of the second switch tube is grounded together with the filter unit.

[0023] In one embodiment, the driving circuit further includes:

[0024] The rectifier module is connected between the first circulating current suppression module and the secondary side of the transformer module.

[0025] In one embodiment, the rectifier module includes:

[0026] A first rectifier diode, wherein the positive electrode of the first rectifier diode is used to connect to the high potential end of the secondary side of the transformer module, and the negative electrode of the first rectifier diode is connected to the first input end of the first circulating current suppression module;

[0027] A second rectifier diode, the cathode of the second rectifier diode is used to connect to the low potential end of the secondary side of the transformer module, and the anode of the second rectifier diode is connected to the second input end of the first circulating current suppression module.

[0028] In a second aspect, the present application further provides an inverter, the inverter comprising:

[0029] An inverter full-bridge circuit, wherein the input end of the inverter full-bridge circuit is used to connect a bus capacitor;

[0030] Such as the driving circuit of the inverter full-bridge circuit in the above embodiment.

[0031] The driving circuit and inverter of the inverter full-bridge circuit have at least the following beneficial effects:

[0032] By connecting the first circulating current suppression module between the transformer module and the driving module, the loop current formed in the lower bridge arm when a phase is turned on and off is consumed, thereby reducing the value and time of the tail current, thereby avoiding circulating current crosstalk and reducing the turn-off loss of the power switch unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 is a schematic structural diagram of a driving circuit of an inverter full-bridge circuit in one embodiment;

[0035] Figure 2 is a schematic structural diagram of a driving circuit of an inverter full-bridge circuit in another embodiment;

[0036] Figure 3 A schematic diagram of a partial circuit structure of a driving circuit of an inverter full-bridge circuit in one embodiment;

[0037] Figure 4 It is a schematic diagram of a partial circuit structure of a second commutation inhibition module in a driving circuit of an inverter full-bridge circuit in an embodiment;

[0038] Figure 5 It is a schematic diagram of a turn-off time test curve of an inverter of a driving circuit that does not use the inverter full-bridge circuit of the present application in one embodiment;

[0039] Figure 6 The figure is a schematic diagram of a turn-off time test curve of an inverter using a drive circuit of the inverter full-bridge circuit of the present application in one embodiment. DETAILED DESCRIPTION

[0040] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0042] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0043] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0044] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0045] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0046] As described in the background technology, when designing the drive circuit of the inverter full-bridge circuit, in order to ensure the independence of each power switch unit (such as IGBT) and avoid mutual interference, an isolated drive power supply is generally used. However, for example, in a three-phase inverter module, due to the limitation of board space and the consideration of simplifying the power supply system, the drive power supplies of the three IGBTs in the lower bridge arm sometimes share the same power supply. This design method can effectively save board space, reduce the use of isolation transformer modules, and simplify the layout and wiring difficulty of the printed circuit board (PCB).

[0047] However, sharing the same power supply may cause some problems during operation. When one of the IGBTs is turned on or off, its current change rate (di / dt) will generate an induced electromotive force on the parasitic inductance of the PCB traces and copper busbars. This will affect the grounding point level of the phase, destroy the balance of the grounding point potential of the other two phases of the IGBT, and may cause circulating current crosstalk. This LC oscillation will affect the signals associated with the grounding point, such as the waveform of Vge (gate-to-emitter voltage) and blanking capacitor, which may cause the IGBT turn-off time to be extended, increase the turn-off loss, and even affect the shoot-through protection time in the shoot-through state. When the level change caused by di / dt is not too drastic, it can usually be ignored; however, when the change is very drastic, corresponding measures need to be taken, such as adding magnetic beads at the IGBT pins to suppress the oscillation, or changing to a three-way isolated power supply solution. Although adding magnetic beads can improve the circulating current phenomenon, the amplitude-frequency characteristics of the magnetic beads and the complexity of LC oscillation may cause other circuit safety issues. At the same time, the selection of magnetic beads is relatively complicated, which will increase the instability of the system and the time cost of R&D.

[0048] Based on the above reasons, Figure 1As shown, the present application provides a driving circuit of an inverter full-bridge circuit, the power supply end of the driving circuit is connected to an external power supply through a transformer module 30, and the driving circuit includes multiple driving modules 2 and a first circulating current suppression module 4. The input end of each driving module 2 is used to connect to the secondary side of the transformer module 30, and the output end of each driving module 2 is used to respectively connect to the controlled end of each lower bridge arm power switch unit 50, and the controlled end of the driving module 2 is used to access the driving control signal, and the transformer module 30, the lower bridge arm power switch unit 50 and each driving module 2 are connected to a common ground; the first circulating current suppression module 4 is connected between the transformer module 30 and the driving module 2.

[0049] Among them, the inverter full-bridge circuit 500 is mainly used to convert the DC power in the DC bus 70 into AC power and transmit it to the power grid 90, and mainly includes a lower bridge arm power switch unit 50 and an upper bridge arm power switch unit 52, wherein the setting position and connection relationship of the lower bridge arm power switch unit 50 and the upper bridge arm power switch unit 52 in the inverter full-bridge circuit 500 are well known to those skilled in the art and will not be repeated here. The drive module 2 refers to an electronic circuit for receiving a drive control signal (such as a PWM signal) and converting it into a signal suitable for controlling the lower bridge arm power switch unit 50 in the inverter full-bridge circuit. Each drive module 2 may include components such as an amplifier, a comparator, an optical coupler isolator, and a gate driver to ensure that the drive signal can effectively control the conduction and shutdown of the lower bridge arm power switch unit 50. The first circulating current suppression module 4 refers to a circuit part for suppressing the circulating current phenomenon that may occur in the inverter full-bridge circuit. The first circulating current suppression module 4 may include an inductor, a capacitor, a diode or other passive components, and possible active components such as transistors, which work together to reduce or eliminate the circulating current, thereby improving the performance and reliability of the entire inverter full-bridge circuit.

[0050] For example, Figure 2 As shown, Figure 2 FIG. 1 is a schematic diagram of the structure of an inverter full-bridge circuit in a specific embodiment, and the inverter full-bridge circuit is taken as an example for explanation, wherein the lower bridge arm power switch unit 50 is an insulated gate bipolar transistor IGBT. Figure 2 It can be seen that the power supply end of the driving module 2 of the three lower bridge arm IGBTs is connected to the low potential end T2_net10 and the high potential end T2_net12 of the secondary side of the transformer module 30, and the three lower bridge arm IGBTs are connected to a common ground through the grounding end T2_net11, thereby realizing the sharing of the driving power supply.

[0051] When the above circuit is running, when the power switch unit of a phase in the inverter full-bridge circuit is turned on or off, the current change rate (di / dt) at the time of turning on and off and the parasitic inductance of the copper busbar between the three-phase lower bridge arms generate an induced electromotive force, which will cause the grounding point level of the phase to change, breaking the balance of the grounding point potential of the lower bridge arms of the other two phases, resulting in circulating current crosstalk, causing the inverter full-bridge circuit to be turned off too long, resulting in increased IGBT turn-off loss. For example, Figure 2 As shown in the figure, when the insulated gate bipolar transistor (IGBT) VT5 double pulse (+15V and -8V in the figure) is turned on, the induced electromotive force of the inductor Le5 is positive at the top and negative at the bottom, and the potential at point b is broken (the original potential at point a = the potential at point b = the potential at point c), so there will be current from point a and point c flowing to point b. There are only inductors and capacitors in the entire circulating loop, and the oscillation of LC increases the value and time of the tail current generated by the IGBT when it is turned off, thereby increasing the turn-off loss of the IGBT. Based on this, Figure 1 As shown, by adding a first circulating current suppression module 4 to the circulating current loop (i.e., connecting a first circulating current suppression module 4 to the voltage output trunk line of the secondary side of the transformer module 30), energy is consumed in the first circulating current suppression module 4, thereby reducing the LC oscillation time and thus reducing the duration of the tail current, thereby avoiding circulating current crosstalk and reducing the turn-off loss of the lower bridge arm power switch unit 50.

[0052] The driving circuit of the above-mentioned inverter full-bridge circuit consumes the loop current formed in the lower bridge arm when a phase is turned on and off by connecting the first circulating current suppression module 4 between the transformer module 30 and the driving module 2, thereby reducing the value and time of the tail current, thereby avoiding circulating current crosstalk and reducing the turn-off loss of the lower bridge arm power switch unit 50.

[0053] In an exemplary embodiment, Figure 3 As shown, the first circulating current suppression module 4 includes: a first circulating current suppression resistor R2 and a second circulating current suppression resistor R3. The first end of the first circulating current suppression resistor R2 is used to connect the high potential end of the secondary side of the transformer module 30, and the second end of the first circulating current suppression resistor R2 is connected to the first input end of the driver module 2; the first end of the second circulating current suppression resistor R3 is used to connect the low potential end of the secondary side of the transformer module 30, and the second end of the second circulating current suppression resistor R3 is connected to the second input end of the driver module 2.

[0054] Exemplarily, a first circulating current suppression resistor R2 is connected between the high potential end and the ground end of the secondary side of the transformer module 30, and a second circulating current suppression resistor R3 is connected between the low potential end and the ground end of the secondary side of the transformer module 30, so that when the double pulse is turned on, the loop current formed between the high potential end and the ground end, and the loop current formed between the low potential end and the ground end can be respectively consumed by the first circulating current suppression resistor R2 and the second circulating current suppression resistor R3. Wherein, in some embodiments, the resistance value range of the first circulating current suppression resistor R2 and the second circulating current suppression resistor R3 is 2-10 ohms, so as to avoid the influence of the IGBT driving voltage due to the excessive resistance, and the suppression of the circulating current resistor due to the excessive resistance. If the output average current of the transformer module 30 is Io, the power that the resistor can withstand should be greater than 5*Io*Io*R, and the overall power of the resistor can be matched by connecting and paralleling, leaving a certain margin to ensure that the circulating current suppression resistor will not generate too much voltage drop and heat.

[0055] In the present embodiment, a specific and implementable method is provided for the first circulating current suppression module 4, and by connecting the first and second circulating current suppression resistors R3 between the secondary high potential end and the low potential end and the ground end of the transformer module 30, the loop current formed when the double pulses are turned on can be effectively suppressed, and at the same time, it helps to prevent power loss and unnecessary heat caused by circulating current, thereby improving the efficiency and stability of the system.

[0056] In an exemplary embodiment, the driving circuit further includes: a plurality of second circulating current suppression modules 6. Each second circulating current suppression module 6 is respectively connected between the ground terminal of each lower bridge arm power switch unit 50 and the ground.

[0057] For example, in the above embodiment, after the first circulating current suppression module 4 is used, the circulating current has been greatly reduced. On this basis, the second circulating current suppression module 6 is provided to further suppress the circulating current phenomenon. Figure 2 Taking the inverter full-bridge circuit shown as an example, a second circulating current suppression module 6 can be added to the E-pole pin of the IGBT. Secondly, after the action of the first circulating current suppression module 4, the selection of the electrical parameters (such as power and resistance) of the second circulating current suppression module 6 is clearer. For example, in some embodiments, the resistance value of the second circulating current suppression module 6 ranges from 0.2 to 0.6 ohms, and the specific selection should match the size of the driving resistance in the specification and the actual measurement results, so that when the second circulating current suppression module 6 works with the first circulating current suppression module 4, it can better suppress the loop current, increase the system stability, and reduce the heat loss of the lower bridge arm power switch unit 50.

[0058] In this embodiment, on the basis of the first circulating current suppression module 4, a second circulating current suppression module 6 is further added between the ground terminal of the lower bridge arm power switch unit 50 and the ground, so that the loop current can be better suppressed under the combined action of the two, thereby increasing the system stability while reducing the heat loss of the lower bridge arm power switch unit 50.

[0059] In an exemplary embodiment, Figure 4 As shown, the second circulating current suppression module 6 includes third circulating current suppression resistors, and each third circulating current suppression resistor is connected between the ground terminal of the corresponding lower bridge arm power switch unit 50 and the ground.

[0060] For example, Figure 4 The circuit diagram shown is used as an example to illustrate. Figure 4 FIG. 1 is a partial structural diagram of an inverter full-bridge circuit in some embodiments. Figure 4 As shown, the third circulating current suppression resistor may refer to resistor R6, and the suppression of the circulating current is achieved by connecting the resistor R6 to the E-pole pin of the IGBT. Figure 4 The circuit structure shown is only for illustration and is not intended to be a specific limitation. Figure 4 The meaning, function and connection relationship of other electronic components therein can be directly known by those skilled in the art from the figure, and will not be described in detail here.

[0061] In an exemplary embodiment, Figure 3 As shown, the driving module 2 includes a filter unit 22 and a driving unit 24. The first input end of the filter unit 22 is used to connect to the first end of the secondary side of the transformer module 30, and the second input end of the filter unit 22 is used to connect to the second end of the secondary side of the transformer module 30; the input end of the driving unit 24 is connected to the output end of the filter unit 22, and the output end of the driving unit 24 is connected to the controlled end of the lower bridge arm power switch unit 50, and the controlled end of the driving unit 24 is used to access the driving control signal; wherein the driving unit 24, the filter unit 22, the transformer module 30 and the lower bridge arm power switch unit 50 are connected to the ground.

[0062] Exemplarily, the double pulses output from both ends of the transformer module 30 are input to the drive unit 24 after the noise is filtered out by the filter unit 22. The drive unit 24 selects the pulse signal input to the controlled end of the lower bridge arm power switch unit 50 according to the received drive control signal, thereby realizing the normal operation of the inverter full-bridge circuit.

[0063] In this embodiment, the double pulse signal output from the secondary side of the transformer module 30 is filtered by the filter unit 22 to remove clutter and noise in the signal, improve the signal quality, and ensure that the signal received by the drive unit 24 is clean and stable, thereby improving the working stability and reliability of the entire circuit. The drive unit 24 can select a suitable pulse signal to control the lower bridge arm power switch unit 50 according to the received pulse width modulation (PWM) drive signal, so as to accurately control the switching action of the power switch and improve the efficiency and performance of the inverter full-bridge circuit.

[0064] In an exemplary embodiment, Figure 3 As shown, the filter unit 22 includes a plurality of first capacitors connected in parallel between a first input terminal of the filter unit 22 and ground, and a plurality of second capacitors connected in parallel between a second input terminal of the filter unit 22 and ground.

[0065] For example, Figure 3 The circuit structure diagram shown in FIG. 1 is used as an example for explanation, wherein the first capacitor includes capacitor C2 and capacitor C4; the second capacitor includes capacitor C3 and capacitor C5. Since the input power of the driving module 2 is a double pulse input, a plurality of first capacitors connected in parallel and a plurality of second capacitors connected in parallel are respectively provided at the two input ends of the double pulses to filter the high pulse signal and the low pulse signal respectively, thereby ensuring the quality of the input signal.

[0066] In an exemplary embodiment, Figure 3 As shown, the driving unit 24 includes a first switch tube Q4 and a second switch tube Q5. The collector of the first switch tube Q4 is connected to the output end of the filter unit 22, and the base of the first switch tube Q4 is used to access the driving control signal; the emitter of the second switch tube Q5 is connected to the emitter of the first switch tube Q4, and the base of the second switch tube Q5 is used to access the driving control signal, and the collector of the second switch tube Q5 and the filter unit 22 are grounded together.

[0067] Exemplarily, the first switch tube Q4 and the second switch tube Q5 are selectively turned on according to the received driving control signal, so as to pull the controlled end of the lower bridge arm power switch unit 50 to different potentials, thereby realizing the driving control of the lower bridge arm power switch unit 50. Regarding how to realize the driving control of the lower bridge arm power switch unit 50 through the first switch tube Q4 and the second switch tube Q5 in this embodiment, those skilled in the art can understand it by Figure 2 The circuit structure schematic diagram shown is known and will not be repeated here.

[0068] In an exemplary embodiment, Figure 3 As shown, the driving circuit further includes a rectifier module 8. The rectifier module 8 is connected between the first circulating current suppression module 4 and the secondary side of the transformer module 30.

[0069] Exemplarily, by setting a rectifier module 8 between the first circulating current suppression module 4 and the transformer module 30, the AC signal output from the secondary side of the transformer module 30 can be rectified and converted into a DC signal to provide a stable DC power supply for subsequent circuits and loads. Secondly, through the rectification process, the fluctuation and noise of the output signal can be reduced and the quality of the power supply can be improved, which is crucial for the stable operation of electronic equipment. In addition, the rectifier module 8 ensures that the current on the first circulating current suppression module 4 is unidirectional, thereby improving the efficiency and effect of circulating current suppression.

[0070] In an exemplary embodiment, Figure 3 As shown, the rectifier module 8 includes a first rectifier diode D2 and a second rectifier diode D3. The positive electrode of the first rectifier diode D2 is used to connect the high potential end of the secondary side of the transformer module 30, and the negative electrode of the first rectifier diode D2 is connected to the first input end of the first circulating current suppression module 4; the negative electrode of the second rectifier diode D3 is used to connect the low potential end of the secondary side of the transformer module 30, and the positive electrode of the second rectifier diode D3 is connected to the second input end of the first circulating current suppression module 4.

[0071] For example, Figure 3 As shown, the first rectifier diode D2 allows the positive half-cycle current of the high potential end to pass through, while the second rectifier diode D3 allows the negative half-cycle current of the low potential end to pass through, thereby obtaining a unidirectional current at the input end of the first circulating current suppression module 4; the rectifier diode is combined with the circulating current suppression module to effectively suppress the loop current. The rectifier diode ensures that the current on the circulating current suppression resistor is unidirectional, thereby improving the efficiency and effect of circulating current suppression. Secondly, on the secondary side of the transformer module 30, due to the presence of inductance, when the current is suddenly interrupted, a very high reverse voltage will be generated, and the rectifier diode can effectively prevent this voltage from damaging the subsequent circuit.

[0072] In an exemplary embodiment, the present application further provides an inverter, which includes an inverter full-bridge circuit and a driving circuit of the inverter full-bridge circuit as in the above embodiment. The input end of the inverter full-bridge circuit is used to connect a bus capacitor.

[0073] For example, Figure 5 and Figure 6 As shown, the drive circuit of the inverter full-bridge circuit in the above embodiment can effectively reduce the turn-off time of the lower bridge arm power switch unit, for example, Figure 5 The ΔX=3.4us shown is reduced to ΔX=1.68us.

[0074] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0075] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A driving circuit for an inverter full-bridge circuit, characterized in that: The power supply end of the driving circuit is connected to an external power supply through a transformer module, and the driving circuit comprises: A plurality of driving modules, wherein the input end of each driving module is used to connect to the secondary side of the transformer module, the output end of each driving module is used to be respectively connected to the controlled end of each lower bridge arm power switch unit, the controlled end of the driving module is used to access the driving control signal, and the transformer module, the lower bridge arm power switch unit and each driving module are connected to a common ground; A first circulating current suppression module is connected between the transformer module and the driving module.

2. The driving circuit of the inverter full-bridge circuit according to claim 1, characterized in that: The first circulation suppression module includes: a first circulating current suppression resistor, wherein a first end of the first circulating current suppression resistor is used to connect to a high potential end of a secondary side of the transformer module, and a second end of the first circulating current suppression resistor is connected to a first input end of the driving module; A second circulating current suppression resistor, wherein the first end of the second circulating current suppression resistor is used to connect to the low potential end of the secondary side of the transformer module, and the second end of the second circulating current suppression resistor is connected to the second input end of the driving module.

3. The driving circuit of the inverter full-bridge circuit according to claim 1, characterized in that: The driving circuit further includes: A plurality of second circulating current suppression modules, each of which is correspondingly connected between the ground terminal of each lower bridge arm power switch unit and the ground.

4. The driving circuit of the inverter full-bridge circuit according to claim 3, characterized in that: The second circulating current suppression module includes a plurality of third circulating current suppression resistors connected in parallel, and each of the third circulating current suppression resistors is connected between the ground terminal of the corresponding lower bridge arm power switch unit and the ground.

5. The driving circuit of the inverter full-bridge circuit according to claim 1, characterized in that: The driving module comprises: A filter unit, wherein a first input end of the filter unit is used to connect to a first end of a secondary side of the transformer module, and a second input end of the filter unit is used to connect to a second end of the secondary side of the transformer module; A driving unit, wherein an input end of the driving unit is connected to an output end of the filtering unit, an output end of the driving unit is connected to a controlled end of the lower bridge arm power switch unit, and the controlled end of the driving unit is used to access the driving control signal; Wherein, the driving unit, the filtering unit, the voltage transformation module and the lower bridge arm power switch unit are connected to a common ground.

6. The driving circuit of the inverter full-bridge circuit according to claim 5, characterized in that: The filter unit includes a plurality of first capacitors connected in parallel between a first input terminal of the filter unit and ground, and a plurality of second capacitors connected in parallel between a second input terminal of the filter unit and ground.

7. The driving circuit of the inverter full-bridge circuit according to claim 5, characterized in that: The driving unit comprises: a first switch tube, wherein the collector of the first switch tube is connected to the output end of the filter unit, and the base of the first switch tube is used to access the drive control signal; A second switch tube, wherein the emitter of the second switch tube is connected to the emitter of the first switch tube, the base of the second switch tube is used to access the drive control signal, and the collector of the second switch tube is grounded together with the filter unit.

8. The driving circuit of the inverter full-bridge circuit according to any one of claims 1 to 7, characterized in that: The driving circuit further includes: A rectifier module is connected between the first circulating current suppression module and the secondary side of the transformer module.

9. The driving circuit of the inverter full-bridge circuit according to claim 8, characterized in that: The rectifier module comprises: a first rectifier diode, wherein the anode of the first rectifier diode is used to connect to the high potential end of the secondary side of the transformer module, and the cathode of the first rectifier diode is connected to the first input end of the first circulating current suppression module; A second rectifier diode, wherein the cathode of the second rectifier diode is used to connect to the low potential end of the secondary side of the transformer module, and the anode of the second rectifier diode is connected to the second input end of the first circulating current suppression module.

10. An inverter, characterized in that: The inverter comprises: An inverter full-bridge circuit, wherein the input end of the inverter full-bridge circuit is used to connect a bus capacitor; A driving circuit for an inverter full-bridge circuit as claimed in any one of claims 1 to 9.

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