Inverter protection circuit

Abstract

The utility model discloses an inverter protection circuit, which relates to the technical field of inverters and comprises a power supply module used for supplying power; the protection control module is used for electric energy transmission work; the inversion module is used for inversion adjustment; the voltage sampling module is used for voltage sampling; the voltage comparison module is used for overvoltage detection and normal power supply detection; the self-locking control module is used for outputting a high-level signal in a self-locking manner during overvoltage; and the logic control module is used for controlling the timing control module to perform timing work when the self-locking control module performs self-locking work and the power supply module normally supplies power, and controlling the reset work of the self-locking control module after timing is finished. According to the inverter protection circuit, overvoltage detection and normal power supply detection can be carried out, the self-locking control module controls the protection control module to carry out self-locking power-off work during overvoltage, and the logic control module triggers the timing control module to regularly control self-locking reset of the self-locking control module when the voltage drops back to normal power supply.

Description

Technical Field

[0001] The utility model relates to the technical field of inverters, in particular to an inverter protection circuit. Background Art

[0002] An inverter is a reverse transformer that converts direct current into alternating current. The input DC voltage is converted into pulsed alternating current through the inverter module in the inverter, and then converted into several AC voltages with different pulse amplitudes through the inverter transformer for output. To ensure the safety of the inverter, existing inverters use an input protection circuit composed of a comparator, a protection switch, a self-locking device, etc. at the input end to perform self-locking power-off protection when the input is overvoltage. A few inverters also have the function of self-locking and self-recovery, but usually when the input voltage is lower than the overvoltage limit, a delayed self-recovery power supply is performed. At this time, overvoltage is still likely to occur again, which affects the inverter protection effect. In addition, the energy consumption of the input protection circuit is high, so it needs to be improved. Utility Model Content

[0003] The embodiment of the utility model provides an inverter protection circuit to solve the problems raised in the above background technology.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] An inverter protection circuit includes: a power supply module, a protection control module, an inverter module, a voltage sampling module, a voltage comparison module, a self-locking control module, a logic control module and a timing control module;

[0006] A power module is used to receive direct current power and stabilize the direct current power;

[0007] A protection control module, connected to the power module, the self-locking control module and the inverter module, for transmitting the electric energy connected to the power module to the inverter module, for receiving the self-locking protection signal output by the self-locking control module and stopping the electric energy transmission work;

[0008] The inverter module is used to perform inversion and regulation on the input electric energy and provide electric energy to the electric load;

[0009] A voltage sampling module, connected to the power module, for sampling the voltage of the electric energy connected to the power module and outputting a first sampling signal;

[0010] A voltage comparison module, connected to the voltage sampling module, for setting a first voltage threshold and an overvoltage threshold, for outputting a first control signal when the first sampling signal is greater than the overvoltage threshold, and for outputting a second control signal when the first sampling signal is lower than the first voltage threshold;

[0011] A self-locking control module, connected to the voltage comparison module, the power supply module and the timing control module, for receiving a first control signal, for performing self-locking processing on the first control signal and outputting a self-locking protection signal, for receiving a timing reset signal output by the timing control module and stopping the self-locking operation;

[0012] a logic control module connected to the voltage comparison module, the power module, the self-locking control module and the timing control module, for receiving the electric energy processed by the power module, for performing logic calculation on the second control signal and the self-locking protection signal, and for transmitting the received electric energy to the timing control module when the self-locking control module performs self-locking work and the first sampling signal is lower than the first voltage threshold;

[0013] The timing control module is used to receive the electric energy transmitted by the logic control module and start the timing work, and is used to output a timing reset signal after the timing ends.

[0014] As a further solution of the utility model: the power module includes a power interface, a first capacitor and a voltage stabilizing device; the voltage sampling module includes a first resistor and a second resistor; the protection control module includes a first relay switch; the inverter module includes a first inverter device, a first inductor and a second capacitor;

[0015] Preferably, the first end of the power interface is connected to one end of the first capacitor, the first end of the first resistor, the input end of the voltage stabilizing device and the moving end of the first relay switch, the second end of the first resistor is grounded through the second resistor, the other end of the first capacitor, the second input end of the first inverter device and the second end of the power interface are all grounded, the fixed end of the first relay switch is connected to the first input end of the first inverter device, the first output end of the first inverter device is connected to one end of the second capacitor and one end of the power load through the first inductor, the second output end of the first inverter device is connected to the other end of the second capacitor and the other end of the power load, and the output end of the voltage stabilizing device is connected to the voltage comparison module, the self-locking control module and the protection control module.

[0016] As a further solution of the utility model: the voltage comparison module includes a third resistor, a fourth resistor, a second potentiometer, a first comparator, a first potentiometer and a first diode;

[0017] Preferably, one end of the third resistor is connected to the output end of the voltage stabilizing device, the other end of the third resistor is connected to one end of the second potentiometer, the other end of the second potentiometer is grounded through a fourth resistor, the slider end of the second potentiometer is connected to the in-phase end of the first comparator, the inverting end of the first comparator is connected to one end of the first potentiometer and the second end of the first resistor, the output end of the first comparator is connected to the logic control module, the other end of the first potentiometer and the slider end are both connected to the cathode of the first diode, and the anode of the first diode is connected to the self-locking control module.

[0018] As a further solution of the utility model: the self-locking control module includes a second diode, a third diode, a first logic chip, a fifth resistor and a second switch tube;

[0019] Preferably, the anode of the second diode is connected to the anode of the first diode, the cathode of the second diode is connected to the first input terminal of the first logic chip and the cathode of the third diode, the anode of the third diode is connected to the output terminal of the first logic chip, the second input terminal of the first logic chip is connected to the collector of the second switch tube and is connected to the output terminal of the voltage stabilizing device through the fifth resistor, the emitter of the second switch tube is grounded, and the base of the second switch tube is connected to the timing control module.

[0020] As a further solution of the utility model: the protection control module also includes a third switch tube, a first relay and a sixth resistor;

[0021] Preferably, the base of the third switch tube is connected to the output end of the first logic chip, the emitter of the third switch tube is grounded, the collector of the third switch tube is connected to one end of the first relay, and the other end of the first relay is connected to the output end of the voltage stabilizing device through a sixth resistor.

[0022] As a further solution of the utility model: the logic control module includes a second logic chip and a first switch tube;

[0023] Preferably, the first input terminal and the second input terminal of the second logic chip are respectively connected to the output terminal of the first comparator and the output terminal of the first logic chip, the output terminal of the second logic chip is connected to the base of the first switching tube, the collector of the first switching tube is connected to the output terminal of the voltage stabilizing device, and the emitter of the first switching tube is connected to the timing control module.

[0024] As a further solution of the utility model: the timing control module includes a third capacitor, a fourth diode, a seventh resistor, a fourth capacitor and a first timer;

[0025] Preferably, one end of the third capacitor, the fourth end and the eighth end of the first timer are all connected to the emitter of the first switching tube, the other end of the third capacitor is connected to the cathode of the fourth diode, one end of the seventh resistor, the second end and the sixth end of the first timer, the fifth end of the first timer is grounded through the fourth capacitor, the first end of the first timer, the other end of the seventh resistor and the anode of the first diode are all grounded, and the third end of the first timer is connected to the base of the second switching tube.

[0026] Compared with the prior art, the beneficial effects of the utility model are as follows: the inverter protection circuit of the utility model comprises a voltage sampling module cooperating with a voltage comparison module to perform overvoltage detection and normal power supply detection on the electric energy of the input protection control module; when overvoltage occurs, the self-locking control module controls the protection control module to perform self-locking power-off operation; and when the voltage drops back to normal power supply, the logic control module triggers the timing control module to time the self-locking reset of the self-locking control module, and the timing control module performs timing operation only when the output of the logic control module is at a high level, thereby reducing circuit loss; after the self-locking control module is reset, it will supply electric energy to the inverter module again, thereby improving the protection effect on the inverter module. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments of the utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 The present invention provides a schematic block diagram of an inverter protection circuit.

[0029] Figure 2 A circuit diagram of an inverter protection circuit provided in an example of the utility model.

[0030] Figure 3 This is a connection circuit diagram of a timing control module provided by an example of the utility model. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0032] In one embodiment, see Figure 1 , an inverter protection circuit, comprising: a power module 1, a protection control module 2, an inverter module 3, a voltage sampling module 4, a voltage comparison module 5, a self-locking control module 6, a logic control module 7 and a timing control module 8;

[0033] Specifically, the power module 1 is used to access direct current power and perform voltage stabilization on the direct current power;

[0034] The protection control module 2 is connected to the power module 1, the self-locking control module 6 and the inverter module 3, and is used to transmit the electric energy connected to the power module 1 to the inverter module 3, and is used to receive the self-locking protection signal output by the self-locking control module 6 and stop the electric energy transmission work;

[0035] The inverter module 3 is used to perform inversion and regulation processing on the input electric energy and provide electric energy to the electric load;

[0036] A voltage sampling module 4, connected to the power module 1, for sampling the voltage of the electric energy connected to the power module 1 and outputting a first sampling signal;

[0037] A voltage comparison module 5, connected to the voltage sampling module 4, for setting a first voltage threshold and an overvoltage threshold, for outputting a first control signal when the first sampling signal is greater than the overvoltage threshold, and for outputting a second control signal when the first sampling signal is lower than the first voltage threshold;

[0038] A self-locking control module 6 is connected to the voltage comparison module 5, the power supply module 1 and the timing control module 8, and is used to receive a first control signal, to perform self-locking processing on the first control signal and output a self-locking protection signal, and to receive a timing reset signal output by the timing control module 8 and stop the self-locking operation;

[0039] The logic control module 7 is connected to the voltage comparison module 5, the power module 1, the self-locking control module 6 and the timing control module 8, and is used to receive the electric energy processed by the power module 1, and is used to perform logic calculations on the second control signal and the self-locking protection signal, and transmit the received electric energy to the timing control module 8 when the self-locking control module 6 performs self-locking work and the first sampling signal is lower than the first voltage threshold;

[0040] The timing control module 8 is used to receive the electric energy transmitted by the logic control module 7 and start the timing work, and to output the timing reset signal after the timing ends.

[0041] In a specific embodiment, the power supply module 1 may adopt a power supply circuit composed of a power supply interface, a voltage stabilizer, etc. to access the required DC power, and filter and stabilize the DC power; the protection control module 2 may adopt a protection control circuit composed of relays, transistors, etc. to receive the power output of the power supply module 1 and control the power state of the input inverter module 3; the inverter module 3 may adopt an inverter circuit composed of an inverter device, an inductor, a capacitor, etc. to achieve inverter regulation of the power; the voltage sampling module 4 may adopt a voltage sampling circuit composed of a resistor voltage divider circuit to perform voltage sampling on the power output of the power supply module 1; the voltage comparison module 5 may adopt a diode, a comparator, etc. The voltage comparison circuit can perform overvoltage detection and normal power supply detection on the sampled signal; the above-mentioned self-locking control module 6 can adopt a self-locking control circuit composed of logic chips, transistors, etc., which can self-lock the input high level and reset the signal output by the timing control module 8; the above-mentioned logic control module 7 can adopt a logic control circuit composed of logic chips, etc., which can control the operation of the timing control module 8 when the self-locking control module 6 is self-locking and the first sampling signal is lower than the first voltage threshold; the above-mentioned timing control module 8 can adopt a timing control circuit composed of a timer, etc., which starts the timing operation when power is supplied, and continuously outputs a high-level timing reset signal after the timing ends.

[0042] In another embodiment, see Figure 1 , Figure 2 and Figure 3 The power module 1 includes a power interface, a first capacitor C1 and a voltage stabilizing device; the voltage sampling module 4 includes a first resistor R1 and a second resistor R2; the protection control module 2 includes a first relay switch K1-1; the inverter module 3 includes a first inverter device T1, a first inductor L1 and a second capacitor C2;

[0043] Specifically, the first end of the power interface is connected to one end of the first capacitor C1, the first end of the first resistor R1, the input end of the voltage stabilizing device and the moving end of the first relay switch K1-1, the second end of the first resistor R1 is grounded through the second resistor R2, the other end of the first capacitor C1, the second input end of the first inverter device T1 and the second end of the power interface are all grounded, the fixed end of the first relay switch K1-1 is connected to the first input end of the first inverter device T1, the first output end of the first inverter device T1 is connected to one end of the second capacitor C2 and one end of the power load through the first inductor L1, the second output end of the first inverter device T1 is connected to the other end of the second capacitor C2 and the other end of the power load, and the output end of the voltage stabilizing device is connected to the voltage comparison module 5, the self-locking control module 6 and the protection control module 2.

[0044] In a specific embodiment, the voltage stabilizing device may adopt an LM317 voltage stabilizer; the first relay switch K1-1 may adopt a normally closed switch; the first inverter T1 may adopt a single-phase inverter and a three-phase inverter, but is not limited to a single-phase inverter and a three-phase inverter.

[0045] Further, the voltage comparison module 5 includes a third resistor R3, a fourth resistor R4, a second potentiometer RP2, a first comparator A1, a first potentiometer RP1 and a first diode D1;

[0046] Specifically, one end of the third resistor R3 is connected to the output end of the voltage stabilizing device, the other end of the third resistor R3 is connected to one end of the second potentiometer RP2, the other end of the second potentiometer RP2 is grounded through the fourth resistor R4, the slider end of the second potentiometer RP2 is connected to the in-phase end of the first comparator A1, the inverting end of the first comparator A1 is connected to one end of the first potentiometer RP1 and the second end of the first resistor R1, the output end of the first comparator A1 is connected to the logic control module 7, the other end and the slider end of the first potentiometer RP1 are both connected to the cathode of the first diode D1, and the anode of the first diode D1 is connected to the self-locking control module 6.

[0047] In a specific embodiment, the third resistor R3, the fourth resistor R4 and the second potentiometer RP2 provide a first voltage threshold, which can satisfy the electric energy regulated by the first inverter device T1, and will not be elaborated here; the first comparator A1 can adopt an LM197 comparator; the first potentiometer RP1 and the first diode D1 provide an overvoltage threshold, and when the sampled signal is greater than the overvoltage threshold, the first diode D1 is broken down.

[0048] Furthermore, the self-locking control module 6 includes a second diode D2, a third diode D3, a first logic chip J1, a fifth resistor R5 and a second switch tube VT2;

[0049] Specifically, the anode of the second diode D2 is connected to the anode of the first diode D1, the cathode of the second diode D2 is connected to the first input terminal of the first logic chip J1 and the cathode of the third diode D3, the anode of the third diode D3 is connected to the output terminal of the first logic chip J1, the second input terminal of the first logic chip J1 is connected to the collector of the second switch tube VT2 and is connected to the output terminal of the voltage stabilizing device through the fifth resistor R5, the emitter of the second switch tube VT2 is grounded, and the base of the second switch tube VT2 is connected to the timing control module 8.

[0050] In a specific embodiment, the first logic chip J1 can be used as a logic chip to cooperate with the second diode D2, the third diode D3 and the fifth resistor R5 for signal self-locking; the second switch tube VT2 can be used as an NPN transistor to reset the first logic chip J1.

[0051] Furthermore, the protection control module 2 also includes a third switch tube VT3, a first relay K1 and a sixth resistor R6;

[0052] Specifically, the base of the third switch tube VT3 is connected to the output end of the first logic chip J1, the emitter of the third switch tube VT3 is grounded, the collector of the third switch tube VT3 is connected to one end of the first relay K1, and the other end of the first relay K1 is connected to the output end of the voltage stabilizing device through the sixth resistor R6.

[0053] In a specific embodiment, the third switch tube VT3 can be an NPN transistor; the first relay K1 controls the closing and opening of the first relay switch K1 - 1 by magnetic attraction.

[0054] Furthermore, the logic control module 7 includes a second logic chip J2 and a first switch tube VT1;

[0055] Specifically, the first input terminal and the second input terminal of the second logic chip J2 are respectively connected to the output terminal of the first comparator A1 and the output terminal of the first logic chip J1, the output terminal of the second logic chip J2 is connected to the base of the first switch tube VT1, the collector of the first switch tube VT1 is connected to the output terminal of the voltage stabilizing device, and the emitter of the first switch tube VT1 is connected to the timing control module 8.

[0056] In a specific embodiment, the second logic chip J2 can be an AND logic chip; the first switch tube VT1 can be an NPN transistor.

[0057] Further, the timing control module 8 includes a third capacitor C3, a fourth diode D4, a seventh resistor R7, a fourth capacitor C4 and a first timer U1;

[0058] Specifically, one end of the third capacitor C3, the fourth end and the eighth end of the first timer U1 are all connected to the emitter of the first switch tube VT1, the other end of the third capacitor C3 is connected to the cathode of the fourth diode D4, one end of the seventh resistor R7, the second end and the sixth end of the first timer U1, the fifth end of the first timer U1 is grounded through the fourth capacitor C4, the first end of the first timer U1, the other end of the seventh resistor R7 and the anode of the first diode are all grounded, and the third end of the first timer U1 is connected to the base of the second switch tube VT2.

[0059] In a specific embodiment, the first timer U1 can use a NE555 chip, and cooperate with the third capacitor C3, the fourth diode D4, the seventh resistor R7 and the fourth capacitor C4 to form a timing control circuit. When powered, it starts to output a low-level signal regularly, and outputs a high-level signal after the timing ends.

[0060] In an inverter protection circuit of the present embodiment, direct current power is connected to the power interface, the first resistor R1 and the second resistor R2 perform voltage sampling, the voltage stabilizing device performs voltage stabilizing regulation, and the connected power is transmitted to the first inverter device T1 through the first relay switch K1-1, and the first inverter device T1 performs inversion regulation to provide alternating current power to the power load. The third resistor R3, the fourth resistor R4 and the second potentiometer RP2 provide a first voltage threshold, and cooperate with the first comparator A1 to perform normal power supply detection. When the sampled signal is less than the first voltage threshold, it will indicate that the voltage input to the first inverter device T1 is in a safe range. When overvoltage occurs, the first diode D1 is broken down, so that the first input terminal of the first logic chip J1 is High level, the first logic chip J1 will self-lock. Even if the overvoltage disappears, if the sampled signal is not lower than the first voltage threshold, the first logic chip J1 will maintain a high level signal and control the third switch tube VT3 to turn on. The first relay K1 is energized and controls the first relay switch K1-1 to turn off until the sampled signal is lower than the first voltage threshold and the first logic chip J1 outputs a high level. The second logic chip J2 will control the first switch tube VT1 to turn on, control the first timer U1 to be energized, and control the second switch tube VT2 to turn on after the timing ends, so that the first logic chip J1 self-locks and resets, the third switch tube VT3 is turned off, the first relay switch K1-1 is closed again, the first switch tube VT1 is turned off, and the first timer U1 stops working.

[0061] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0062] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An inverter protection circuit, characterized in that: The inverter protection circuit includes: a power module, a protection control module, an inverter module, a voltage sampling module, a voltage comparison module, a self-locking control module, a logic control module and a timing control module; The power module is used to receive direct current power and perform voltage stabilization on the direct current power; The protection control module is connected to the power module, the self-locking control module and the inverter module, and is used to transmit the electric energy connected to the power module to the inverter module, and is used to receive the self-locking protection signal output by the self-locking control module and stop the electric energy transmission work; The inverter module is used to perform inversion and regulation processing on the input electric energy and provide electric energy to the electric load; The voltage sampling module is connected to the power module and is used to perform voltage sampling on the electric energy connected to the power module and output a first sampling signal; The voltage comparison module is connected to the voltage sampling module, and is used to set a first voltage threshold and an overvoltage threshold, and is used to output a first control signal when the first sampling signal is greater than the overvoltage threshold, and is used to output a second control signal when the first sampling signal is lower than the first voltage threshold; The self-locking control module is connected to the voltage comparison module, the power supply module and the timing control module, and is used to receive the first control signal, to perform self-locking processing on the first control signal and output a self-locking protection signal, and to receive a timing reset signal output by the timing control module and stop the self-locking operation; The logic control module is connected to the voltage comparison module, the power module, the self-locking control module and the timing control module, and is used to receive the electric energy processed by the power module, to perform logic calculations on the second control signal and the self-locking protection signal, and to transmit the received electric energy to the timing control module when the self-locking control module performs self-locking work and the first sampling signal is lower than the first voltage threshold; The timing control module is used to receive the electric energy transmitted by the logic control module and start the timing work, and is used to output a timing reset signal after the timing ends.

2. The inverter protection circuit according to claim 1, characterized in that: The power module includes a power interface, a first capacitor and a voltage stabilizing device; the voltage sampling module includes a first resistor and a second resistor; the protection control module includes a first relay switch; the inverter module includes a first inverter device, a first inductor and a second capacitor; The first end of the power interface is connected to one end of the first capacitor, the first end of the first resistor, the input end of the voltage stabilizing device and the moving end of the first relay switch, the second end of the first resistor is grounded through the second resistor, the other end of the first capacitor, the second input end of the first inverter device and the second end of the power interface are all grounded, the fixed end of the first relay switch is connected to the first input end of the first inverter device, the first output end of the first inverter device is connected to one end of the second capacitor and one end of the power load through the first inductor, the second output end of the first inverter device is connected to the other end of the second capacitor and the other end of the power load, and the output end of the voltage stabilizing device is connected to the voltage comparison module, the self-locking control module and the protection control module.

3. The inverter protection circuit according to claim 2, characterized in that: The voltage comparison module includes a third resistor, a fourth resistor, a second potentiometer, a first comparator, a first potentiometer and a first diode; One end of the third resistor is connected to the output end of the voltage stabilizing device, the other end of the third resistor is connected to one end of the second potentiometer, the other end of the second potentiometer is grounded through a fourth resistor, the slider end of the second potentiometer is connected to the in-phase end of the first comparator, the inverting end of the first comparator is connected to one end of the first potentiometer and the second end of the first resistor, the output end of the first comparator is connected to the logic control module, the other end of the first potentiometer and the slider end are both connected to the cathode of the first diode, and the anode of the first diode is connected to the self-locking control module.

4. The inverter protection circuit according to claim 3, characterized in that: The self-locking control module includes a second diode, a third diode, a first logic chip, a fifth resistor and a second switch tube; The anode of the second diode is connected to the anode of the first diode, the cathode of the second diode is connected to the first input terminal of the first logic chip and the cathode of the third diode, the anode of the third diode is connected to the output terminal of the first logic chip, the second input terminal of the first logic chip is connected to the collector of the second switch tube and is connected to the output terminal of the voltage stabilizing device through the fifth resistor, the emitter of the second switch tube is grounded, and the base of the second switch tube is connected to the timing control module.

5. The inverter protection circuit according to claim 4, characterized in that: The protection control module also includes a third switch tube, a first relay and a sixth resistor; The base of the third switch tube is connected to the output end of the first logic chip, the emitter of the third switch tube is grounded, the collector of the third switch tube is connected to one end of the first relay, and the other end of the first relay is connected to the output end of the voltage stabilizing device through a sixth resistor.

6. The inverter protection circuit according to claim 5, characterized in that: The logic control module includes a second logic chip and a first switch tube; The first input terminal and the second input terminal of the second logic chip are respectively connected to the output terminal of the first comparator and the output terminal of the first logic chip, the output terminal of the second logic chip is connected to the base of the first switch tube, the collector of the first switch tube is connected to the output terminal of the voltage stabilizing device, and the emitter of the first switch tube is connected to the timing control module.

7. The inverter protection circuit according to claim 6, characterized in that: The timing control module includes a third capacitor, a fourth diode, a seventh resistor, a fourth capacitor and a first timer; One end of the third capacitor, the fourth end and the eighth end of the first timer are all connected to the emitter of the first switch tube, the other end of the third capacitor is connected to the cathode of the fourth diode, one end of the seventh resistor, the second end and the sixth end of the first timer, the fifth end of the first timer is grounded through the fourth capacitor, the first end of the first timer, the other end of the seventh resistor and the anode of the first diode are all grounded, and the third end of the first timer is connected to the base of the second switch tube.

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