CN112510987A

CN112510987A - IGBT drive circuit with PFC overcurrent protection, power factor correction device and equipment

Info

Publication number: CN112510987A
Application number: CN202011435469.XA
Authority: CN
Inventors: 胡威
Original assignee: GD Midea Air Conditioning Equipment Co Ltd; Foshan Shunde Midea Electric Science and Technology Co Ltd
Current assignee: GD Midea Air Conditioning Equipment Co Ltd; Foshan Shunde Midea Electric Science and Technology Co Ltd
Priority date: 2020-12-07
Filing date: 2020-12-07
Publication date: 2021-03-16

Abstract

The invention discloses an IGBT drive circuit with PFC overcurrent protection, a power factor correction device and household electrical appliance equipment, wherein the drive circuit comprises: the driving chip is used for generating a driving signal according to a PFC control signal received by the input pin and outputting the driving signal to the IGBT through the output pin so as to drive the IGBT to be switched on or switched off; the output end of the PFC current detection unit is connected with a current feedback pin of the driving chip, and the PFC current detection unit is used for detecting PFC current so as to output current detection voltage to the current feedback pin; the driving chip is also used for comparing the current detection voltage with a preset overcurrent protection voltage and closing the output pin when the current detection voltage is determined to be greater than or equal to the preset overcurrent protection voltage according to the comparison result. Therefore, the use number of components can be effectively reduced, the circuit design is simplified, and the reliability and the control precision of the circuit are improved.

Description

IGBT drive circuit with PFC overcurrent protection, power factor correction device and equipment

Technical Field

The invention relates to the technical field of power electronics, in particular to an IGBT (insulated gate bipolar transistor) driving circuit with PFC (power factor correction) overcurrent protection, a power factor correction device and household electrical appliance equipment.

Background

At present, for overcurrent protection of an IGBT driving circuit, a PFC overcurrent protection circuit is mainly built through a comparator to protect a power device IGBT, but the use number of components and parts is increased, the design complexity of the circuit is increased, and the reliability of the circuit is reduced.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, a first objective of the present invention is to provide an IGBT driving circuit with PFC overcurrent protection, which integrates an overcurrent protection circuit into a driving chip, so as to effectively reduce the number of components, simplify the circuit design, and improve the reliability and control accuracy of the circuit.

The second objective of the present invention is to provide a power factor correction device.

A third object of the present invention is to provide a home appliance.

In order to achieve the above object, an embodiment of a first aspect of the present invention provides an IGBT driving circuit with PFC overcurrent protection, including: the driving chip is used for generating a driving signal according to a PFC control signal received by the input pin and outputting the driving signal to the IGBT through the output pin so as to drive the IGBT to be switched on or switched off; the output end of the PFC current detection unit is connected with a current feedback pin of the driving chip, and the PFC current detection unit is used for detecting PFC current so as to output current detection voltage to the current feedback pin; the driving chip is also used for comparing the current detection voltage with a preset overcurrent protection voltage and closing the output pin when the current detection voltage is determined to be greater than or equal to the preset overcurrent protection voltage according to the comparison result.

According to the IGBT driving circuit with the PFC overcurrent protection, the driving chip generates the driving signal according to the PFC control signal received by the input pin, the driving signal is output to the IGBT through the output pin so as to drive the IGBT to be switched on or switched off, the PFC current is detected through the PFC current detection unit so as to output the current detection voltage to the current feedback pin of the driving chip, the current detection voltage is compared with the preset overcurrent protection voltage through the driving chip, and the output pin is closed when the current detection voltage is determined to be larger than or equal to the preset overcurrent protection voltage according to the comparison result. Therefore, the overcurrent protection circuit is integrated into the drive chip, so that the use number of components can be effectively reduced, the circuit design is simplified, and the reliability and the control precision of the circuit are improved.

According to one embodiment of the invention, an EN/FLT pin of the driving chip is connected to the MCU, and the driving chip also outputs a PFC overcurrent interruption signal to the MCU through the EN/FLT pin when the current detection voltage is determined to be greater than or equal to the preset overcurrent protection voltage, so that the MCU turns off the PFC control signal according to the PFC overcurrent interruption signal.

According to an embodiment of the present invention, a driving chip includes: the positive input end of the comparison unit is connected with the current feedback pin, the negative input end of the comparison unit is connected to a preset overcurrent protection voltage supply end, and the comparison unit outputs an overcurrent protection signal when the current detection voltage is greater than or equal to the preset overcurrent protection voltage; and the logic processing unit generates a driving signal according to a PFC control signal received by the input pin, outputs the driving signal through the output pin, and outputs a closing signal to close the output pin when receiving an overcurrent protection signal.

According to an embodiment of the present invention, the driving chip further includes a first switching tube and a first resistor, a control end of the first switching tube is connected to the second output end of the logic processing unit, a first end of the first switching tube is connected to one end of the first resistor and has a first node, a second end of the first switching tube is connected to a first reference ground, another end of the first resistor is connected to a first preset power supply, and the first node is connected to an EN/FLT pin of the driving chip, wherein the logic processing unit further controls the first switching tube to be turned on according to the overcurrent protection signal, so as to output the PFC overcurrent interruption signal to the MCU through the EN/FLT pin.

According to an embodiment of the present invention, the IGBT driving circuit with PFC overcurrent protection further includes a delay filtering unit connected between the EN/FLT pin and the MCU, and the delay filtering unit is further charged according to a second preset power supply after the PFC control signal is turned off, so as to input an enable signal to a third input terminal of the logic processing unit through the EN/FLT pin.

According to one embodiment of the present invention, a delay filtering unit includes: one end of the second resistor is connected to a second preset power supply; one end of the first capacitor is connected with the other end of the second resistor and is provided with a second node, the other end of the first capacitor is grounded, and the second node is connected with the EN/FLT pin; one end of the third resistor is connected with the second node, and the other end of the third resistor is connected to the MCU; and one end of the second capacitor is connected with the other end of the third resistor, and the other end of the second capacitor is grounded.

According to an embodiment of the present invention, the above IGBT driving circuit with PFC overcurrent protection further includes a first filtering unit connected between the input pin and the MCU, and the first filtering unit includes: one end of the fourth resistor is connected to the MCU, and the other end of the fourth resistor is connected with the input pin; one end of the fifth resistor is connected with one end of the fourth resistor, and the other end of the fifth resistor is grounded; and one end of the third capacitor is connected with the other end of the fourth resistor, and the other end of the third capacitor is grounded.

According to an embodiment of the present invention, the above IGBT driving circuit with PFC overcurrent protection further includes a driving adjustment unit connected between the output pin and the G pole of the IGBT, and the driving adjustment unit includes: one end of the sixth resistor is connected with the output pin, and the other end of the sixth resistor is connected with the G pole of the IGBT; the seventh resistor is connected with the sixth resistor in parallel; one end of the eighth resistor is connected with the output pin; the cathode of the first diode is connected with the other end of the eighth resistor, and the anode of the first diode is connected with the G electrode of the IGBT; the anode of the voltage stabilizing tube is connected to the COM pin of the driving chip and the E pole of the IGBT and then grounded, and the cathode of the voltage stabilizing tube is connected with the G pole of the IGBT; and a ninth resistor connected between the G pole and the E pole of the IGBT.

According to an embodiment of the present invention, a PFC current detection unit includes: one end of the current detection resistor is connected with the E pole of the IGBT and then grounded, and the other end of the current detection resistor is connected to the bridge stack negative pole end of the rectifier bridge stack and is provided with a third node; one end of the tenth resistor is connected with the third node, and the other end of the tenth resistor is connected with the current feedback pin; one end of the eleventh resistor is connected with the other end of the tenth resistor, and the other end of the eleventh resistor is grounded; and the fourth capacitor is connected with the eleventh resistor in parallel.

In order to achieve the above object, a second embodiment of the present invention provides a power factor correction device, which includes the above IGBT driving circuit with PFC overcurrent protection.

According to the power factor correction device provided by the embodiment of the invention, the IGBT drive circuit with the PFC overcurrent protection can effectively reduce the use number of components, simplify the circuit design and improve the reliability and control precision of the circuit.

In order to achieve the above object, a third aspect of the present invention provides a household electrical appliance, including the above power factor correction device.

According to the household appliance provided by the embodiment of the invention, through the power factor correction device, the use number of components can be effectively reduced, the circuit design is simplified, and the reliability and the control precision of the circuit are improved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a schematic structural diagram of an IGBT driving circuit with PFC overcurrent protection according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an IGBT driving circuit with PFC overcurrent protection according to another embodiment of the present invention;

FIG. 3 is a schematic diagram of an internal structure of a driver chip according to an embodiment of the invention;

FIG. 4 is a block diagram of a power factor correction device according to one embodiment of the present invention;

fig. 5 is a block diagram of a home device according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

The following describes an IGBT drive circuit with PFC overcurrent protection, a power factor correction device, and a home appliance according to an embodiment of the present invention with reference to the drawings.

Fig. 1 is a schematic structural diagram of an IGBT driving circuit with PFC overcurrent protection according to an embodiment of the present invention, and as shown in fig. 1, the IGBT driving circuit with PFC overcurrent protection includes: a driver chip 10 and a PFC current detection unit 20.

The input pin IN of the driving chip 10 is connected to the MCU, the output pin OUT of the driving chip 10 is connected to the G pole of the IGBT, and the driving chip 10 is used for generating a driving signal according to a PFC control signal received by the input pin IN and outputting the driving signal to the IGBT through the output pin OUT so as to drive the IGBT to be switched on or switched off; the output end of the PFC current detection unit 20 is connected to the current feedback pin OCP of the driver chip 10, and the PFC current detection unit 20 is configured to detect a PFC current to output a current detection voltage to the current feedback pin OCP; the driving chip 10 is further configured to compare the current detection voltage with a preset over-current protection voltage, and close the output pin OUT when the current detection voltage is determined to be greater than or equal to the preset over-current protection voltage according to the comparison result.

Specifically, when the IGBT is subjected to drive control, the MCU outputs a PFC control signal to an input pin IN of the driver chip 10, and the driver chip 10 generates a drive signal such as a PWM signal according to the PFC control signal after receiving the PFC control signal, and outputs the drive signal to a G pole of the IGBT through an output pin OUT to control the IGBT to be turned on or off; meanwhile, the PFC current detection unit 20 detects the PFC current in real time, for example, detects a current between a bridge rectifier (not specifically shown in fig. 1) and an E pole of the IGBT in real time to serve as the PFC current, and outputs a current detection voltage corresponding to the PFC current, and feeds the current detection voltage back to the current feedback pin OCP of the driver chip 10, and the driver chip 10 compares the current detection voltage with a preset overcurrent protection voltage after receiving the current detection voltage, wherein if the current detection voltage is greater than or equal to the preset overcurrent protection voltage, the output of the driving signal to the output pin OUT is stopped, so that the IGBT stops working, and the IGBT is prevented from being impacted by a large current, and the IGBT is subjected to overcurrent protection.

In the above embodiment, through with the overcurrent protection circuit integration to driver chip in, can effectively reduce the use quantity of components and parts, simplify circuit design, improve the reliability of circuit, simultaneously through the inside reference voltage that sets up of driver chip promptly overcurrent protection voltage, when can effectively avoiding obtaining reference voltage through bleeder circuit partial pressure, because of the problem that the control accuracy is low that receives the divider resistance influence to lead to, control accuracy has effectively been improved, and carry out overcurrent protection through driver chip, the time delay is little, can realize the timely protection to IGBT.

In one embodiment, an EN/FLT pin of the driver chip 10 is connected to the MCU, and the driver chip 10 further outputs a PFC overcurrent interruption signal to the MCU through the EN/FLT pin when it is determined that the current detection voltage is greater than or equal to the preset overcurrent protection voltage, so that the MCU turns off the PFC control signal according to the PFC overcurrent interruption signal.

That is to say, when the current detection voltage is greater than or equal to the preset overcurrent protection voltage, the driving chip 10 outputs the PFC overcurrent interrupt signal to the MCU through the EN/FLT pin while stopping outputting the driving signal to the IGBT, and the MCU stops outputting the PFC control signal to the driving chip 10 after receiving the PFC overcurrent interrupt signal, so that on one hand, the resource occupation of the MCU can be reduced, such as continuous generation of the PFC control signal, and on the other hand, when the built-in program of the driving chip is abnormal, the driving signal is continuously generated according to the PFC control signal to control the IGBT, which results in the overcurrent protection failure.

In one embodiment, as shown with reference to fig. 2, the driving chip 10 includes: the current detection circuit comprises a comparison unit 11 and a logic processing unit 12, wherein a positive input end of the comparison unit 11 is connected with a current feedback pin OCP, a negative input end of the comparison unit 11 is connected to a preset overcurrent protection voltage supply end Vocth, and the comparison unit 11 outputs an overcurrent protection signal when a current detection voltage is greater than or equal to a preset overcurrent protection voltage; a first input end of the logic processing unit 12 is connected to an output end of the comparing unit 11, a second input end of the logic processing unit 12 is connected to the input pin IN, a first output end of the logic processing unit 12 is connected to the output pin OUT, the logic processing unit 12 generates a driving signal according to a PFC control signal received by the input pin IN, outputs the driving signal through the output pin OUT, and outputs a shutdown signal to shut down the output pin OUT when receiving an overcurrent protection signal.

In an embodiment, with continued reference to fig. 2, the driving chip 10 further includes a first switch Q1 and a first resistor R1, a control terminal of the first switch Q1 is connected to the second output terminal of the logic processing unit 12, a first terminal of the first switch Q1 is connected to one terminal of the first resistor R1 and has a first node J1, a second terminal of the first switch Q1 is connected to a first reference ground, another terminal of the first resistor R1 is connected to a first preset power supply, for example, +3.3V, and the first node J1 is connected to an EN/FLT pin of the driving chip 10, wherein the logic processing unit 12 further controls the first switch Q1 to be turned on according to an overcurrent protection signal to output an overcurrent PFC interrupt signal to the MCU through the EN/FLT pin.

Specifically, referring to fig. 2, after receiving the PFC control signal through the input pin IN, the driver chip 10 may first perform amplification processing on the PFC control signal through an internal amplifier, and then input the PFC control signal to the first input terminal of the logic processing unit 12, so that the logic processing unit 12 generates a driving signal, and outputs the driving signal to the output pin OUT through an output circuit formed by the second switching tube Q2 and the third switching tube Q3, so as to perform driving control on the IGBT. Meanwhile, the driving chip 10 receives a current detection voltage corresponding to the PFC current through the current feedback pin OCP, compares the current detection voltage with a preset overcurrent protection voltage provided by a preset overcurrent protection voltage providing terminal Vocth through the comparing unit 11, and outputs an overcurrent protection signal to the second input terminal of the logic processing unit 12 when the current detection voltage is greater than or equal to the preset overcurrent protection voltage, at which time the logic processing unit 12 stops outputting the driving signal to the output pin OUT; meanwhile, under the action of the overcurrent protection signal, the first switching tube Q1 is turned on, the first node J1 is at a low level, that is, the EN/FLT pin outputs the PFC overcurrent interruption signal, and the MCU stops outputting the PFC control signal to the driver chip 10 according to the PFC overcurrent interruption signal.

Therefore, the preset overcurrent protection voltage is arranged in the driving chip, the current detection voltage and the preset overcurrent protection voltage are compared through the internal comparator to judge whether the overcurrent protection value is reached, and when the overcurrent protection value is reached, the internal logic circuit calculates and judges to timely close the driving signal (without passing through the external delay circuit), so that the impact time of the current on the IGBT is effectively reduced, and the IGBT can be more effectively protected.

In an embodiment, referring to fig. 2 to fig. 3, the above-mentioned IGBT driving circuit with PFC overcurrent protection further includes a delay filtering unit 30 connected between the EN/FLT pin and the MCU, and the delay filtering unit 30 is further charged according to a second preset power supply, for example, +5V, after the PFC control signal is turned off, so as to input an enable signal to the third input terminal of the logic processing unit 12 through the EN/FLT pin.

In one embodiment, referring to fig. 3, the delay filtering unit 30 includes: a second resistor R2, a first capacitor C1, a third resistor R3 and a second capacitor C2, wherein one end of the second resistor R2 is connected to a second preset power supply, such as + 5V; one end of the first capacitor C1 is connected with the other end of the second resistor R2 and is provided with a second node J2, the other end of the first capacitor C1 is grounded, and the second node J2 is connected with an EN/FLT pin; one end of a third resistor R3 is connected with a second node J2, and the other end of the third resistor R3 is connected to the MCU; one end of the second capacitor C2 is connected to the other end of the third resistor R3, and the other end of the second capacitor C2 is grounded.

Specifically, referring to fig. 2, when the current detection voltage is greater than or equal to the preset overcurrent protection voltage, the comparing unit 11 outputs an overcurrent protection signal to the second input end of the logic processing unit 12, the logic processing unit 12 controls the first switching tube Q1 to be turned on according to the overcurrent protection signal, at this time, the EN/FLT pin of the driving chip 10 outputs a PFC overcurrent interruption signal, that is, a low level signal, and the PFC overcurrent interruption signal is transmitted to the MCU through the delay circuit formed by the second resistor R2 and the first capacitor C1 and the RC filter circuit formed by the third resistor R3 and the second capacitor C2, wherein when the discharging of the first capacitor C1 and the second capacitor C2 is completed, the PF pin of the MCU is pulled down, the MCU detects the PFC overcurrent interruption signal, and at this time, the MCU performs an operation process to turn off the PFC control signal.

After the first capacitor C1 and the second capacitor C2 are discharged, the level of the EN/FLT pin of the driver chip 10 is pulled down to the lowest value, and then the first capacitor C1 and the second capacitor C2 are charged under the action of a second preset power supply, such as +5V, to reach the set value of the high level of the driver chip 10, the EN/FLT pin resumes enabling, but at this time, the MCU has stopped outputting the PFC control signal and remains for a period of time (the time for maintaining off is longer than the time for resuming enabling of the EN/FLT pin), so the circuit still cannot operate.

IN one embodiment, referring to fig. 3, the IGBT driving circuit with PFC overcurrent protection further includes a first filtering unit 40 connected between the input pin IN and the MCU, where the first filtering unit 40 includes: the circuit comprises a fourth resistor R4, a fifth resistor R5 and a third capacitor C3, wherein one end of the fourth resistor R4 is connected to the MCU, and the other end of the fourth resistor R4 is connected with an input pin IN; one end of the fifth resistor R5 is connected with one end of the fourth resistor R4, and the other end of the fifth resistor R5 is grounded; one end of the third capacitor C3 is connected to the other end of the fourth resistor R4, and the other end of the third capacitor C3 is grounded. Therefore, the first filtering unit 40 filters the PFC control signal output by the MCU, so that the stability of the PFC control signal can be ensured, and the reliability of control is further ensured.

In one embodiment, referring to fig. 3, the IGBT driving circuit with PFC overcurrent protection further includes a driving adjusting unit 50 connected between the output pin OUT and the G pole of the IGBT for adjusting the switching speed of the IGBT. Further, the driving adjustment unit 50 includes: a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a first diode D1, a voltage regulator DZ and a ninth resistor R9. One end of the sixth resistor R6 is connected with the output pin OUT, and the other end of the sixth resistor R6 is connected with the G pole of the IGBT; the seventh resistor R7 is connected in parallel with the sixth resistor R6; one end of the eighth resistor R8 is connected to the output pin OUT; the cathode of the first diode D1 is connected with the other end of the eighth resistor R8, and the anode of the first diode D1 is connected with the G pole of the IGBT; the anode of the voltage-regulator tube DZ is connected to the COM pin of the driving chip 10 and the E pole of the IGBT and then grounded, and the cathode of the voltage-regulator tube DZ is connected with the G pole of the IGBT; the ninth resistor R9 is connected between the G pole and the E pole of the IGBT.

In one embodiment, referring to fig. 3, the PFC current detection unit 20 includes: a current detection resistor Ri, a tenth resistor R10, an eleventh resistor R11 and a fourth capacitor C4, wherein one end of the current detection resistor Ri is connected with the E pole of the IGBT and then grounded, and the other end of the current detection resistor Ri is connected to the bridge stack negative pole end of the rectifier bridge stack BR and is provided with a third node J3; one end of a tenth resistor R10 is connected to the third node J3, and the other end of the tenth resistor R10 is connected to the current feedback pin OCP; one end of the eleventh resistor R11 is connected with the other end of the tenth resistor R10, and the other end of the eleventh resistor R11 is grounded; the fourth capacitor C4 is connected in parallel with the eleventh resistor R11. Optionally, the current detection resistor Ri is a non-inductive resistor. The resistance values of the tenth resistor R10 and the eleventh resistor R11 are calculated and adjusted according to the preset overcurrent protection voltage.

Specifically, the current detection resistor Ri is configured to sample a PFC current (the PFC current is a current between the bridge cathode end of the bridge BR and the E pole of the IGBT), convert a PFC current signal into a voltage signal, and input the voltage signal into the driver chip 10 through the current feedback pin OCP of the driver chip 10 after passing through the voltage division circuit formed by the tenth resistor R10 and the eleventh resistor R11 and the RC filter circuit formed by the tenth resistor R10, the eleventh resistor R11 and the fourth capacitor C4, so as to compare the voltage signal with a preset overcurrent protection voltage set inside the driver chip 10 to determine whether the voltage signal reaches an overcurrent protection value. The overcurrent protection circuit comprises a reference voltage circuit, a resistor and a current detection circuit, wherein the reference voltage circuit is used for obtaining the overcurrent protection voltage, the current detection circuit is used for detecting the current of the current detection circuit, and the current detection circuit is used for comparing and judging the current with the preset overcurrent protection voltage set in the driving chip.

In summary, according to the IGBT driving circuit with PFC overcurrent protection of the embodiment of the invention, the driving chip generates the driving signal according to the PFC control signal received by the input pin, and outputs the driving signal to the IGBT through the output pin to drive the IGBT to be turned on or off, and the PFC current detection unit detects the PFC current to output the current detection voltage to the current feedback pin of the driving chip, and compares the current detection voltage with the preset overcurrent protection voltage through the driving chip, and closes the output pin when the current detection voltage is determined to be greater than or equal to the preset overcurrent protection voltage according to the comparison result. Therefore, the overcurrent protection circuit is integrated into the drive chip, so that the use number of components can be effectively reduced, the circuit design is simplified, and the reliability, the control precision and the protection timeliness of the circuit are improved.

Fig. 4 is a block diagram of a power factor correction device according to an embodiment of the present invention, and referring to fig. 4, the power factor correction device 1000 includes the above-mentioned IGBT driving circuit 100 with PFC overcurrent protection.

According to the power factor correction device provided by the embodiment of the invention, the IGBT drive circuit with the PFC overcurrent protection can effectively reduce the use number of components, simplify the circuit design and improve the reliability, control precision and protection timeliness of the circuit.

Fig. 5 is a block diagram of a home device according to an embodiment of the present invention, and referring to fig. 5, the home device 10000 includes the power factor correction apparatus 1000.

According to the household appliance provided by the embodiment of the invention, through the power factor correction device, the use number of components can be effectively reduced, the circuit design is simplified, and the reliability, the control precision and the protection timeliness of the circuit are improved.

It should be noted that the logic and/or steps represented in the flowcharts or otherwise described herein, such as an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. An IGBT drive circuit with PFC overcurrent protection, characterized by comprising:

the input pin of the driving chip is connected to the MCU, the output pin of the driving chip is connected to the G pole of the IGBT, and the driving chip is used for generating a driving signal according to the PFC control signal received by the input pin and outputting the driving signal to the IGBT through the output pin so as to drive the IGBT to be switched on or switched off;

the output end of the PFC current detection unit is connected with a current feedback pin of the driving chip, and the PFC current detection unit is used for detecting PFC current so as to output current detection voltage to the current feedback pin;

the driving chip is further used for comparing the current detection voltage with a preset overcurrent protection voltage and closing the output pin when the current detection voltage is determined to be greater than or equal to the preset overcurrent protection voltage according to a comparison result.

2. The IGBT driving circuit with PFC overcurrent protection according to claim 1, wherein an EN/FLT pin of the driving chip is connected to the MCU, and the driving chip further outputs a PFC overcurrent interruption signal to the MCU through the EN/FLT pin when determining that the current detection voltage is greater than or equal to the preset overcurrent protection voltage, so that the MCU turns off the PFC control signal according to the PFC overcurrent interruption signal.

3. The IGBT driving circuit with PFC overcurrent protection according to claim 1 or 2, wherein the driving chip comprises:

the positive input end of the comparison unit is connected with the current feedback pin, the negative input end of the comparison unit is connected to a preset overcurrent protection voltage supply end, and the comparison unit outputs an overcurrent protection signal when the current detection voltage is greater than or equal to the preset overcurrent protection voltage;

a first input end of the logic processing unit is connected with an output end of the comparison unit, a second input end of the logic processing unit is connected to the input pin, a first output end of the logic processing unit is connected to the output pin, the logic processing unit generates the driving signal according to the PFC control signal received by the input pin, outputs the driving signal through the output pin, and outputs a closing signal to close the output pin when receiving the overcurrent protection signal.

4. The IGBT driving circuit with PFC overcurrent protection according to claim 3, wherein the driving chip further comprises a first switching tube and a first resistor, a control end of the first switching tube is connected with the second output end of the logic processing unit, a first end of the first switching tube is connected with one end of the first resistor and has a first node, a second end of the first switching tube is connected to a first reference ground, the other end of the first resistor is connected to a first preset power supply, and the first node is connected to an EN/FLT pin of the driving chip, wherein the logic processing unit further controls the first switching tube to be conducted according to the overcurrent protection signal so as to output a PFC overcurrent interruption signal to the MCU through the EN/FLT pin.

5. The IGBT driving circuit with PFC overcurrent protection of claim 4, further comprising a delay filtering unit connected between the EN/FLT pin and the MCU, wherein the delay filtering unit is further charged according to a second preset power supply after the PFC control signal is turned off, so as to input an enable signal to a third input end of the logic processing unit through the EN/FLT pin.

6. The IGBT drive circuit with PFC overcurrent protection of claim 5, wherein the delay filter unit comprises:

one end of the second resistor is connected to the second preset power supply;

one end of the first capacitor is connected with the other end of the second resistor and is provided with a second node, the other end of the first capacitor is grounded, and the second node is connected with the EN/FLT pin;

one end of the third resistor is connected with the second node, and the other end of the third resistor is connected to the MCU;

and one end of the second capacitor is connected with the other end of the third resistor, and the other end of the second capacitor is grounded.

7. The IGBT drive circuit with PFC overcurrent protection of any one of claims 1-6, further comprising a first filtering unit connected between the input pin and the MCU, the first filtering unit comprising:

one end of the fourth resistor is connected to the MCU, and the other end of the fourth resistor is connected with the input pin;

one end of the fifth resistor is connected with one end of the fourth resistor, and the other end of the fifth resistor is grounded;

and one end of the third capacitor is connected with the other end of the fourth resistor, and the other end of the third capacitor is grounded.

8. The IGBT drive circuit with PFC overcurrent protection of any one of claims 1-6, further comprising a drive regulation unit connected between the output pin and the G pole of the IGBT, the drive regulation unit comprising:

one end of the sixth resistor is connected with the output pin, and the other end of the sixth resistor is connected with the G pole of the IGBT;

a seventh resistor connected in parallel with the sixth resistor;

one end of the eighth resistor is connected with the output pin;

a cathode of the first diode is connected with the other end of the eighth resistor, and an anode of the first diode is connected with a G electrode of the IGBT;

the anode of the voltage-stabilizing tube is connected to the COM pin of the driving chip and the E pole of the IGBT and then grounded, and the cathode of the voltage-stabilizing tube is connected with the G pole of the IGBT;

a ninth resistor connected between the G pole and the E pole of the IGBT.

9. The IGBT driving circuit with PFC overcurrent protection according to claim 8, wherein the PFC current detection unit includes:

one end of the current detection resistor is connected with the E pole of the IGBT and then grounded, and the other end of the current detection resistor is connected to the bridge stack negative pole end of the rectifier bridge stack and is provided with a third node;

one end of the tenth resistor is connected with the third node, and the other end of the tenth resistor is connected with the current feedback pin;

one end of the eleventh resistor is connected with the other end of the tenth resistor, and the other end of the eleventh resistor is grounded;

a fourth capacitor in parallel with the eleventh resistor.

10. A power factor correction device, characterized by comprising an IGBT drive circuit with PFC overcurrent protection according to any one of claims 1 to 9.

11. A household appliance comprising a power factor correction device according to claim 10.