Overvoltage suppression device and electronic equipment

Abstract

The utility model discloses an overvoltage suppression device and electronic equipment, and belongs to the technical field of variable frequency driving. The overvoltage suppression device is used for suppressing overvoltage of bus voltage on a bridge arm circuit of a power conversion circuit and comprises a voltage regulation circuit, a voltage sampling circuit and a control circuit, the voltage regulating circuit and the voltage sampling circuit are respectively connected with the bridge arm circuit, and the voltage sampling circuit is used for detecting bus voltage on the bridge arm circuit in real time; the input end of the control circuit is connected with the output end of the voltage sampling circuit, the output end of the control circuit is connected with the input end of the voltage regulation circuit, and the control circuit is used for controlling the voltage regulation circuit to regulate the voltage of the bridge arm circuit according to the bus voltage. According to the invention, the application scene of a three-level reverse charging bus voltage energy suppression scheme is broadened, and meanwhile, the circuit is simplified, so that the circuit is easy to debug and implement.

Description

Technical Field

[0001] The present application relates to the field of variable frequency drive technology, and in particular to an overvoltage suppression device and an electronic device. Background Art

[0002] In the application scenario of three-level inverter plus permanent magnet synchronous direct drive motor, there is a working condition where the belt is transported from top to bottom. Under this condition, if the bus reverse charging overvoltage suppression protection measures are not properly implemented, the inverter may easily shut down due to overvoltage, causing the on-site equipment to stop production. In addition, the inverter bus capacitor and power devices may be easily damaged due to voltage stress problems, eventually causing serious machine explosion problems.

[0003] In this regard, the existing three-level reverse charging bus voltage energy suppression solutions in the relevant technology mainly include the full bus voltage overvoltage energy suppression protection method and the four-quadrant inverter with energy feedback input power supply. However, the former is limited in the application of medium and high voltage inverters, especially medium and high power inverters, and the latter has complex circuits and controls, and will lead to an exponential increase in inverter cost, size and development cycle. Therefore, there is still an urgent need for a three-level reverse charging bus voltage energy suppression solution with unlimited application scenarios, simple circuits, and easy debugging and implementation. Utility Model Content

[0004] The main purpose of this application is to provide an overvoltage suppression device and an electronic device, aiming to broaden the application scenarios of the three-level reverse charging bus voltage energy suppression solution, while simplifying the circuit to make it easy to debug and implement.

[0005] To achieve the above-mentioned object, the present application provides an overvoltage suppression device, which is used to suppress the overvoltage of the bus voltage on the bridge arm circuit of the power conversion circuit, and the overvoltage suppression device includes: a voltage regulation circuit, a voltage sampling circuit and a control circuit;

[0006] The voltage regulating circuit and the voltage sampling circuit are respectively connected to the bridge arm circuit, and the voltage sampling circuit is used to detect the bus voltage on the bridge arm circuit in real time;

[0007] The input end of the control circuit is connected to the output end of the voltage sampling circuit, the output end of the control circuit is connected to the input end of the voltage regulating circuit, and the control circuit is used to control the voltage regulating circuit to regulate the voltage of the bridge arm circuit according to the bus voltage.

[0008] In one embodiment, the bridge arm circuit includes: an upper bridge arm and a lower bridge arm;

[0009] The upper bridge arm includes a first switch component and a second switch component, and the lower bridge arm includes a third switch component and a fourth switch component. The first switch component, the second switch component, the third switch component and the fourth switch component are connected in series in sequence, and the connection point between the second switch component and the third switch component is the midpoint of the bridge arm of the bridge arm circuit.

[0010] In one embodiment, the voltage sampling circuit includes: a first sampling terminal, a second sampling terminal and a third sampling terminal;

[0011] The first sampling end is connected to the first end of the first switch component, the second sampling end is connected to the midpoint of the bridge arm, and the third sampling end is connected to the second end of the fourth switch component.

[0012] In one embodiment, the voltage regulating circuit includes: an upper bridge arm voltage regulating circuit and a lower bridge arm voltage regulating circuit;

[0013] The upper bridge arm voltage regulating circuit is connected to the first switch component and the second switch component respectively, and the lower bridge arm voltage regulating circuit is connected to the third switch component and the fourth switch component respectively.

[0014] In one embodiment, the upper bridge arm voltage regulation circuit includes:

[0015] A first switch tube driving unit, wherein an output end of the first switch tube driving unit is connected to a controlled end of the first switch component;

[0016] a first power resistor, one end of the first power resistor being connected to the first end of the first switch component, and the other end of the first power resistor being connected to the second end of the first switch component and the first end of the second switch component;

[0017] A second switch tube driving unit, wherein the input end of the second switch tube driving unit is connected to the output end of the control circuit, and the output end of the second switch tube driving unit is connected to the controlled end of the second switch component.

[0018] In one embodiment, the lower bridge arm voltage regulation circuit includes:

[0019] A third switch tube driving unit, wherein an output end of the third switch tube driving unit is connected to a controlled end of the third switch component;

[0020] a second power resistor, one end of the second power resistor being connected to the first end of the third switch component, and the other end of the second power resistor being connected to the second end of the third switch component and the first end of the fourth switch component;

[0021] A fourth switch tube driving unit, wherein the input end of the fourth switch tube driving unit is connected to the output end of the control circuit, and the output end of the fourth switch tube driving unit is connected to the controlled end of the fourth switch component.

[0022] In one embodiment, the overvoltage suppression device further includes:

[0023] A current sampling circuit is connected to the voltage regulating circuit, the bridge arm circuit and the control circuit respectively.

[0024] In one embodiment, the overvoltage suppression device further includes:

[0025] A bus filter circuit, one end of the bus filter circuit is connected to the voltage sampling circuit, and the other end of the bus filter circuit is connected to the bridge arm circuit.

[0026] In one embodiment, the bus filter circuit includes a first bus filter capacitor, a first discharge resistor, a second bus filter capacitor and a second discharge resistor, the first end of the first bus filter capacitor is connected to the first end of the first discharge resistor, the second end of the first bus filter capacitor, the second end of the first discharge resistor, the first end of the second bus filter capacitor and the first end of the second discharge resistor are connected in common, and the second end of the second bus filter capacitor is connected to the second end of the second discharge resistor.

[0027] In addition, to achieve the above-mentioned purpose, the present application also provides an electronic device, which includes a power conversion circuit and the overvoltage suppression device as described above.

[0028] The present application proposes an overvoltage suppression device and electronic equipment, which overcomes many defects of the existing three-level reverse charging bus voltage energy suppression scheme in the related art. The overvoltage suppression device includes: a voltage regulation circuit, a voltage sampling circuit and a control circuit; the voltage regulation circuit and the voltage sampling circuit are respectively connected to the bridge arm circuit, and the voltage sampling circuit is used to detect the bus voltage on the bridge arm circuit in real time; the input end of the control circuit is connected to the output end of the voltage sampling circuit, and the output end of the control circuit is connected to the input end of the voltage regulation circuit. The control circuit controls the voltage regulation circuit to regulate the voltage of the bridge arm circuit according to the bus voltage. The present application controls the voltage regulation circuit to regulate the voltage of the bridge arm circuit through the control circuit, so that the resistor consumes this part of the energy, thereby solving the bus voltage overvoltage problem in the down-run power generation condition, and the circuit is simple, easy to debug and implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions will be 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 the structures shown in these drawings without paying any creative work.

[0030] Figure 1 A schematic diagram of the structure of an overvoltage suppression device provided in an embodiment of the present application;

[0031] Figure 2 A schematic diagram of the structure of a bridge arm circuit involved in an overvoltage suppression device provided in an embodiment of the present application;

[0032] Figure 3 A schematic diagram of the structure of a voltage regulating circuit involved in an overvoltage suppression device provided in an embodiment of the present application;

[0033] Figure 4 A detailed structural diagram of an overvoltage suppression device provided in an embodiment of the present application;

[0034] Figure 5 A detailed structural schematic diagram of another overvoltage suppression device provided in an embodiment of the present application.

[0035] Description of Figure Numbers:

[0036] Label name Label name 100 Voltage Regulator Circuit 101 Upper arm voltage regulation circuit 200 Voltage sampling circuit 102 Lower bridge arm voltage regulation circuit 300 Control Circuit P The first sampling terminal O The second sampling terminal N The third sampling terminal S1 to S4 IGBT switch tube D1 to D4 IGBT body diode G1 The first switch tube driving unit G2 The second switch tube driving unit G3 The third switch tube driving unit G4 Fourth switch tube driving unit Rp1 The first power resistor Rp2 Second power resistor H1, H2 Hall Current Sensor C1 First bus filter capacitor R1 The first discharge resistor C2 Second bus filter capacitor R2 Second discharge resistor

[0037] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0039] With the high voltage and high power of semiconductor devices such as IGBT, the application of permanent magnet synchronous direct drive motors in coal mining, metallurgy, ports and other industries has been accelerated. The corresponding three-level topology has better electrical performance such as overall efficiency and harmonics, and the three-level inverter plus permanent magnet synchronous direct drive motor has become more widely used in the industry. However, affected by the geographical environment of different application sites, there are belts transporting from top to bottom. The permanent magnet synchronous motor is prone to power generation after loading. The inverter bus voltage is reversed and the voltage increases. The greater the inverter power, the greater the power generation energy, which leads to a higher bus voltage of the inverter. If the bus reverse charging overvoltage suppression protection measures are not well implemented, the inverter is prone to overvoltage and shutdown, causing the on-site equipment to stop production, and the inverter bus capacitor and power devices are easily damaged due to voltage stress problems, and eventually a serious explosion problem occurs.

[0040] There are two main types of existing three-level reverse charging bus voltage energy suppression:

[0041] 1. Common bus overvoltage energy suppression technologies include full bus voltage overvoltage energy suppression protection, which is commonly used in 380V and 690V voltage inverters. The working bus voltage is low, the required suppression energy is small, and the IGBT voltage and current selection is simple; however, in medium and high input voltage inverters, the working bus voltage is high, and due to different operating conditions, it is usually a high-power motor belt transportation. During the down-transportation condition, the power generation is large, and the inverter bus reverse charging voltage is very high. The commonly used full bus voltage overvoltage energy suppression circuit has high requirements for the withstand voltage level of the IGBT. The increase in the withstand voltage of the IGBT module will bring design cost and size pressure. This method is limited in the application of medium and high voltage inverters, especially medium and high power inverters;

[0042] 2. The existing relatively superior bus overvoltage energy suppression technology is to use a four-quadrant inverter that can feed back energy to the input power supply. The rectifier side uses the IGBT bridge arm circuit with the same symmetrical structure as the inverter side. The same working principle as the inverter side, using the DSP controller, when the bus voltage is reverse-charged and over-voltage, the IGBT on-off combination is controlled by PWM waves to feed back the energy of the reverse-charged inverter bus to the power grid, and through the operation of the four quadrants, the bus is maintained within the rated voltage range. However, this protection method has a complex circuit. In addition to the controller on the inverter side, the inverter also needs to add a controller on the rectifier side, which makes the control complex. In addition, since the IGBT module is used on the rectifier side, the cost, size and development cycle of the inverter are doubled, and the product competitiveness is reduced;

[0043] Based on this, in order to solve the problem of medium and high voltage three-level inverters in belt transportation application scenarios in coal mines, metallurgy, ports and other working conditions, especially in the field with downstream power generation application conditions, the inverter bus is frequently shut down due to overvoltage protection due to reverse charging, or even the bus is seriously overvoltage and causes overvoltage stress damage to power devices. The embodiment of the present application proposes an overvoltage suppression device and electronic equipment, which overcomes the many defects of the existing three-level reverse charging bus voltage energy suppression scheme in the related art. The overvoltage suppression device includes: a voltage regulation circuit, a voltage sampling circuit and a control circuit; the voltage regulation circuit and the voltage sampling circuit are respectively connected to the bridge arm circuit, and the voltage sampling circuit is used to detect the bus voltage on the bridge arm circuit in real time; the input end of the control circuit is connected to the output end of the voltage sampling circuit, and the output end of the control circuit is connected to the input end of the voltage regulation circuit, and the control circuit is used to control the voltage regulation circuit according to the bus voltage to regulate the voltage of the bridge arm circuit. The embodiment of the present application controls the voltage regulation circuit through the control circuit to regulate the voltage of the bridge arm circuit, allowing the resistor to consume this part of the energy, thereby solving the bus voltage overvoltage problem occurring in the downstream power generation condition, and the circuit is simple and easy to debug and implement.

[0044] The overvoltage suppression device and electronic device provided in the embodiments of the present application are specifically described through the following embodiments, and the overvoltage suppression device is first described.

[0045] The present application embodiment provides an overvoltage suppression device, referring to Figure 1 , Figure 1 A schematic diagram of the structure of an overvoltage suppression device provided in an embodiment of the present application, wherein the overvoltage suppression device is used to suppress the overvoltage of the bus voltage on the bridge arm circuit of the power conversion circuit, and the overvoltage suppression device includes: a voltage regulation circuit 100, a voltage sampling circuit 200 and a control circuit 300;

[0046] The voltage regulating circuit 100 and the voltage sampling circuit 200 are respectively connected to the bridge arm circuit, and the voltage sampling circuit 200 is used to detect the bus voltage on the bridge arm circuit in real time;

[0047] The input end of the control circuit 300 is connected to the output end of the voltage sampling circuit 200, and the output end of the control circuit 300 is connected to the input end of the voltage regulating circuit 100. The control circuit 300 is used to control the voltage regulating circuit 100 to regulate the voltage of the bridge arm circuit according to the bus voltage.

[0048] It should be noted that, in this embodiment, the power conversion circuit can be a medium-high voltage three-level topology, the voltage regulation circuit 100 is used to drive the on and off of the switch tube in the bridge arm circuit, the voltage sampling circuit 200 is used to sample the bus voltage of the bridge arm circuit, and send the bus voltage to the control circuit 300. The control circuit 300 may include a DPS controller, which can know whether the bus voltage is overvoltage after receiving it, and output an appropriate PWM wave to the voltage regulation circuit 100 when it is overvoltage, so that the voltage regulation circuit 100 can change the channel state of each switch tube in the bridge arm circuit based on the PWM wave, thereby suppressing the problem of bus voltage overvoltage.

[0049] Reference Figure 2 , in some feasible embodiments, the bridge arm circuit includes: an upper bridge arm and a lower bridge arm;

[0050] The upper bridge arm includes a first switch component and a second switch component, and the lower bridge arm includes a third switch component and a fourth switch component. The first switch component, the second switch component, the third switch component and the fourth switch component are connected in series in sequence, and the connection point between the second switch component and the third switch component is the midpoint of the bridge arm of the bridge arm circuit.

[0051] It can be understood that, in this embodiment, the bridge arm circuit is composed of an upper bridge arm and a lower bridge arm. Figure 2 As shown, each switch component constituting the bridge arm may be an IGBT, that is, including IGBT switch tubes S1 to S4 and IGBT body diodes D1 to D4, the collector of the switch tube S1 is connected to the cathode of the diode D1, the emitter of the switch tube S1 is connected to the anode of the diode D1, the collector of the switch tube S2 and the cathode of the diode D2, the emitter of the switch tube S2 is connected to the anode of the diode D2, the collector of the switch tube S3 and the cathode of the diode D3, the emitter of the switch tube S3 is connected to the anode of the diode D3, the collector of the switch tube S4 and the cathode of the diode D4, and the emitter of the switch tube S4 is connected to the anode of the diode D4.

[0052] Reference Figure 3 In some feasible embodiments, the voltage regulating circuit 100 includes: an upper bridge arm voltage regulating circuit 101 and a lower bridge arm voltage regulating circuit 102;

[0053] The upper bridge arm voltage regulating circuit 101 is respectively connected to the first switch component and the second switch component, and the lower bridge arm voltage regulating circuit 102 is respectively connected to the third switch component and the fourth switch component.

[0054] In this embodiment, in order to ensure the control accuracy of the upper and lower bridge arms, corresponding voltage regulating circuits 100 are respectively provided for the upper bridge arm and the lower bridge arm. Figure 3It can be seen that the structures of the upper and lower bridge arm voltage regulating circuits 102 are basically the same, and only the setting positions are different.

[0055] As an example, the power circuits of the upper and lower bridge arm voltage regulation circuits 102 in this embodiment are symmetrical and consistent, and can work simultaneously or separately: when working simultaneously, bus voltage overvoltage suppression protection is realized; when working separately, bus voltage midpoint balance is adjusted.

[0056] In some feasible embodiments, the upper bridge arm voltage regulating circuit 101 includes:

[0057] A first switch tube driving unit G1, wherein an output end of the first switch tube driving unit G1 is connected to a controlled end of the first switch component;

[0058] A first power resistor Rp1, one end of the first power resistor Rp1 is connected to the first end of the first switch component, and the other end of the first power resistor Rp1 is connected to the second end of the first switch component and the first end of the second switch component;

[0059] A second switch tube driving unit G2, wherein the input end of the second switch tube driving unit G2 is connected to the output end of the control circuit 300, and the output end of the second switch tube driving unit G2 is connected to the controlled end of the second switch component.

[0060] In some feasible embodiments, the lower bridge arm voltage regulating circuit 102 includes:

[0061] A third switch tube driving unit G3, wherein an output end of the third switch tube driving unit G3 is connected to a controlled end of the third switch component;

[0062] a second power resistor Rp2, one end of the second power resistor Rp2 is connected to the first end of the third switch component, and the other end of the second power resistor Rp2 is connected to the second end of the third switch component and the first end of the fourth switch component;

[0063] A fourth switch tube driving unit G4, wherein the input end of the fourth switch tube driving unit G4 is connected to the output end of the control circuit 300, and the output end of the fourth switch tube driving unit G4 is connected to the controlled end of the fourth switch component.

[0064] It should be noted that, in this embodiment, the input ends of the first switch tube driving unit G1 and the third switch tube driving unit G3 can receive the control signal output by the control circuit 300, thereby controlling the conduction and shutdown of the S1 and S3 switch tubes; as an example, when the control signal output by the control circuit 300 is a low-level signal, the first switch tube driving unit G1 and the third switch tube driving unit G3 respectively provide stable negative voltage for the S1 and S3 switch tubes to keep the S1 and S3 switch tubes in the off state continuously, and the D1 and D3 body diodes work during freewheeling; the second switch tube driving unit G2 and the fourth switch tube driving unit G4 respectively provide working PWM waves for the S2 and S4 switch tubes, as well as VCE DESAT detection protection, to ensure that the S2 and S4 switch tubes can be reliably turned on or off; the first power resistor Rp1 and the second power resistor Rp2 are used to consume energy when the bus voltage is overvoltage.

[0065] Reference Figure 4 In some feasible embodiments, the voltage sampling circuit 200 includes: a first sampling terminal P, a second sampling terminal O and a third sampling terminal N;

[0066] The first sampling terminal P is connected to the first terminal of the first switch component, the second sampling terminal O is connected to the midpoint of the bridge arm, and the third sampling terminal N is connected to the second terminal of the fourth switch component.

[0067] It should be noted that, in this embodiment, the voltage adopting circuit is used to realize the sampling of the upper and lower bus voltages. Taking the first sampling terminal P, the second sampling terminal O and the third sampling terminal N as an example, the PO voltage is the upper bus voltage, that is, the voltage across the first switch component and the second switch component, and the ON voltage is the lower bus voltage, that is, the voltage across the third switch component and the fourth switch component.

[0068] Reference Figure 5 In some feasible embodiments, the overvoltage suppression device further includes:

[0069] A current sampling circuit is connected to the voltage regulating circuit 100 , the bridge arm circuit and the control circuit 300 , respectively.

[0070] It should be noted that, in this embodiment, a current sampling circuit may be further provided in the overvoltage suppression device to play the role of overcurrent protection. Specifically, a Hall current sensor (e.g. Figure 5 It can be realized by using H1 and H2 in the figure.

[0071] In some feasible embodiments, the overvoltage suppression device further includes:

[0072] A bus filter circuit, one end of which is connected to the voltage sampling circuit 200 , and the other end of which is connected to the bridge arm circuit.

[0073] It can be understood that, in this embodiment, in order to filter out interference, a bus filter circuit can be added between the voltage sampling circuit 200 and the bridge arm circuit.

[0074] Reference Figure 5 In some feasible embodiments, the bus filter circuit includes a first bus filter capacitor C1, a first discharge resistor R1, a second bus filter capacitor C2 and a second discharge resistor R2, the first end of the first bus filter capacitor C1 is connected to the first end of the first discharge resistor R1, the second end of the first bus filter capacitor C1, the second end of the first discharge resistor R1, the first end of the second bus filter capacitor C2 and the first end of the second discharge resistor R2 are connected in common, and the second end of the second bus filter capacitor C2 is connected to the second end of the second discharge resistor R2.

[0075] As an example, when the inverter is operating in the down-operation condition, when the DSP controller detects that the bus voltage is too high or overvoltage occurs through the upper and lower half bus voltage sampling circuits 200, the DSP controller will simultaneously output a PWM wave with a certain duty cycle to the second switch tube driving unit G2 and the fourth switch tube driving unit G4, and after isolation and amplification by the second switch tube driving unit G2 and the fourth switch tube driving unit G4, respectively drive the S2 and S4 switches to be turned on and off. During the conduction period of S2 and S4, the current in the upper bridge arm voltage regulation circuit 101 flows from the bus P through Rp1, S2, and returns to the bus O. In addition, the current in the lower bridge arm voltage regulation circuit 102 flows from the bus O through Rp2, S4, and returns to the bus N. The resistors Rp1 and Rp2 consume energy, thereby lowering the upper and lower bus voltages; during the shutdown period of S2 and S4, the parasitic inductance of the loop is in the switches S2 and S4. The voltage spike energy generated between the CE poles of S4 returns to the PO and ON bus voltages through D1, C1, D2 and D3, C2, D4 respectively, and is released; the DSP controller controls the switching time of S2 and S4 tubes by outputting appropriate duty cycle PWM waves, which can ensure that the bus voltage is stable within the normal working range and realize the bus voltage reverse charging overvoltage suppression function, thereby avoiding damage to power devices or machine explosion; when the inverter is working, the DSP controller detects that the deviation between the upper and lower half buses is large through the upper and lower half bus voltage sampling circuit 200. If the upper half bus PO voltage is higher than the lower half bus ON voltage, the DSP controller controls the output PWM wave to the second switch tube driving unit G2, opens the upper bridge arm voltage regulation circuit 101, and pulls down the half bus PO voltage, so that the PO voltage is close to or consistent with the ON voltage, ensuring the balance of the midpoint voltage.

[0076] This embodiment provides an overvoltage suppression device. In the application of down-stream power generation conditions, the voltage sampling circuit and the control circuit are used to give a suitable duty cycle PWM wave to control the opening or closing of the IGBT, thereby solving the problem of overvoltage or explosion of the bus voltage of the medium and high voltage three-level inverter due to reverse charging. Compared with other bus overvoltage energy suppression technologies, the overvoltage suppression device provided by this embodiment solves the problems of application scenarios where the bus voltage is too high and the application of IGBT voltage stress selection is limited. The device has the advantages of low cost, simple circuit and control debugging, easy implementation, small size, and strong product competitiveness. In addition, in the three-level topology, the midpoint voltage balance adjustment can also be achieved through upper and lower half bus voltage monitoring and IGBT PWM wave switch control.

[0077] In addition, an embodiment of the present application further provides an electronic device, which includes a power conversion circuit and the overvoltage suppression device provided in the above embodiment.

[0078] As an example, the electronic device may be a photovoltaic inverter, a wind power converter, a power storage converter (PCS, Power Conversion System), a high-voltage inverter, a UPS, an APF / SVG, a high-frequency power supply, or the like.

[0079] Since the electronic device proposed in this embodiment includes the overvoltage suppression device proposed in the above embodiments, it has the beneficial effects of the above embodiments. The specific working process and principle of the overvoltage suppression device are detailed in the overvoltage suppression devices provided in the above embodiments, which will not be described one by one here, and are all within the protection scope of this embodiment.

[0080] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0081] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In addition, the meaning of "and / or" appearing in the full text is to include three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B.

[0082] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0083] It should also be understood that the references to "one embodiment" or "some embodiments" described in the specification of the embodiments of the present application mean that one or more embodiments of the embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0084] It should be noted that the technical solutions of the various embodiments of the present application can be combined with each other, but it must be based on the fact that they can be implemented by technical personnel in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0085] The above are only optional embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An overvoltage suppression device, characterized in that: The overvoltage suppression device is used to suppress the bus voltage overvoltage on the bridge arm circuit of the power conversion circuit, and the overvoltage suppression device includes: a voltage regulation circuit, a voltage sampling circuit and a control circuit; The voltage regulating circuit and the voltage sampling circuit are respectively connected to the bridge arm circuit, and the voltage sampling circuit is used to detect the bus voltage on the bridge arm circuit in real time; The input end of the control circuit is connected to the output end of the voltage sampling circuit, and the output end of the control circuit is connected to the input end of the voltage regulation circuit. The control circuit is used to control the voltage regulation circuit to regulate the voltage of the bridge arm circuit according to the bus voltage.

2. The overvoltage suppression device according to claim 1, characterized in that: The bridge arm circuit includes: an upper bridge arm and a lower bridge arm; The upper bridge arm includes a first switch component and a second switch component, and the lower bridge arm includes a third switch component and a fourth switch component. The first switch component, the second switch component, the third switch component and the fourth switch component are connected in series in sequence, and the connection point between the second switch component and the third switch component is the midpoint of the bridge arm of the bridge arm circuit.

3. The overvoltage suppression device according to claim 2, characterized in that: The voltage sampling circuit includes: a first sampling terminal, a second sampling terminal and a third sampling terminal; The first sampling terminal is connected to the first terminal of the first switch component, the second sampling terminal is connected to the midpoint of the bridge arm, and the third sampling terminal is connected to the second terminal of the fourth switch component.

4. The overvoltage suppression device according to claim 2, wherein: The voltage regulating circuit includes: an upper bridge arm voltage regulating circuit and a lower bridge arm voltage regulating circuit; The upper bridge arm voltage regulation circuit is connected to the first switch component and the second switch component respectively, and the lower bridge arm voltage regulation circuit is connected to the third switch component and the fourth switch component respectively.

5. The overvoltage suppression device according to claim 4, characterized in that: The upper bridge arm voltage regulation circuit includes: a first switch tube driving unit, wherein an output end of the first switch tube driving unit is connected to a controlled end of the first switch component; a first power resistor, one end of the first power resistor being connected to the first end of the first switch component, and the other end of the first power resistor being connected to the second end of the first switch component and the first end of the second switch component; A second switch tube driving unit, wherein the input end of the second switch tube driving unit is connected to the output end of the control circuit, and the output end of the second switch tube driving unit is connected to the controlled end of the second switch component.

6. The overvoltage suppression device according to claim 4, characterized in that: The lower bridge arm voltage regulation circuit includes: a third switch tube driving unit, wherein an output end of the third switch tube driving unit is connected to a controlled end of the third switch component; a second power resistor, one end of the second power resistor being connected to the first end of the third switch component, and the other end of the second power resistor being connected to the second end of the third switch component and the first end of the fourth switch component; A fourth switch tube driving unit, wherein the input end of the fourth switch tube driving unit is connected to the output end of the control circuit, and the output end of the fourth switch tube driving unit is connected to the controlled end of the fourth switch component.

7. The overvoltage suppression device according to claim 1, wherein: The overvoltage suppression device further comprises: A current sampling circuit is connected to the voltage regulation circuit, the bridge arm circuit and the control circuit respectively.

8. The overvoltage suppression device according to claim 1, wherein: The overvoltage suppression device further comprises: A bus filter circuit, one end of the bus filter circuit is connected to the voltage sampling circuit, and the other end of the bus filter circuit is connected to the bridge arm circuit.

9. The overvoltage suppression device according to claim 8, characterized in that: The bus filter circuit includes a first bus filter capacitor, a first discharge resistor, a second bus filter capacitor and a second discharge resistor, the first end of the first bus filter capacitor is connected to the first end of the first discharge resistor, the second end of the first bus filter capacitor, the second end of the first discharge resistor, the first end of the second bus filter capacitor and the first end of the second discharge resistor are connected in common, and the second end of the second bus filter capacitor is connected to the second end of the second discharge resistor.

10. An electronic device, characterized in that: The electronic device includes a power conversion circuit and the overvoltage suppression device according to any one of claims 1 to 9.

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