WO2024120289A1

WO2024120289A1 - Gate drive circuit, vehicle and active heating control method for gate drive circuit

Info

Publication number: WO2024120289A1
Application number: PCT/CN2023/135273
Authority: WO
Inventors: 王明强; 何召朋; 徐玮
Original assignee: 联合汽车电子有限公司
Priority date: 2022-12-05
Filing date: 2023-11-30
Publication date: 2024-06-13
Also published as: CN116215325A

Abstract

A gate drive circuit, a vehicle, and an active heating control method for the gate drive circuit. The gate drive circuit comprises a micro control unit (10), a drive unit (20), a turn-on branch (31), a turn-off branch (32), a first heating branch (33) and a second heating branch (34). In a heating working condition, the drive unit (20) receives a first control signal of the micro control unit (10), sends a heating drive signal to the first heating branch (33) and the second heating branch (34) to control the on and off of a power module, and drives the power module to heat a power battery of the vehicle. When the switching frequency of the power module of an inverter is not changed, the first heating branch (33) and the second heating branch (34) are introduced into the gate drive circuit, so that the turn-on time and turn-off time of the power module are prolonged, the switching loss of the inverter is increased, the electrically-driven active heating rate of the power battery of the electric vehicle in a low-temperature environment is increased, and the electrically-driven active heating effect of the power battery is optimized.

Description

Gate drive circuit, vehicle and active heating control method of gate drive circuit

Technical Field

The present application relates to the field of automotive electronic technology, and in particular to a gate drive circuit, a vehicle, and an active heating control method for the gate drive circuit.

Background technique

The heating technology of the power battery of pure electric vehicles in low temperature environments is directly related to the cruising range and user experience of pure electric vehicles. The electric drive active heating technology is easy to implement, the heating power is controllable, and the cost is low. It is one of the feasible solutions for low-temperature battery heating. The size of the heating power is the core technical indicator of the electric drive active heating, which affects the heating rate and the final effect. Therefore, maximizing the ability of electric drive active heating and providing the largest possible heating power are the key to whether this technology can be better promoted and applied.

However, the currently known electric drive active heating technology mainly uses the motor stator temperature to provide thermal energy to the power battery of the pure electric vehicle. However, the actual temperature rise of the motor stator is very close to the maximum temperature rise limit of the motor stator, and the motor stator heating power has encountered a bottleneck.

Summary of the invention

The present application provides a gate drive circuit, a vehicle and an active heating control method for the gate drive circuit, which can solve the problem of low rate and effect of active heating of the electric drive of the power battery of the current electric vehicle in a low temperature environment.

In a first aspect, an embodiment of the present application provides a gate drive circuit, comprising: a microcontroller unit, a drive unit, an opening branch, a closing branch, a first heating branch, and a second heating branch, wherein the drive unit is connected to the microcontroller unit, the opening branch and the first heating branch are connected in parallel, the closing branch and the second heating branch are connected in parallel, one end of the opening branch and the first heating branch connected in parallel, and one end of the closing branch and the second heating branch connected in parallel are respectively connected to the drive unit, and the other end of the opening branch and the first heating branch connected in parallel, and the other end of the closing branch and the second heating branch connected in parallel are both connected to a power module in an inverter of a subsequent circuit;

Wherein, the gate drive circuit is configured as follows:

In the heating condition, the driving unit receives the first control signal output by the microcontroller unit, and sends a heating driving signal to the first heating branch and the second heating branch according to the first control signal to control the opening and closing of the power module, and drives the power module to heat the power battery of the vehicle;

In a normal driving condition, the driving unit receives a second control signal output by the microcontroller unit, and sends a normal driving signal to the on branch and the off branch according to the second control signal to control the on and off of the power module.

Optionally, in the gate drive circuit, the opening branch includes: a first transistor and a first resistor; the closing branch includes: a second transistor and a second resistor; the first heating branch includes: a third resistor; the second heating branch includes: a fourth resistor; wherein,

The base and collector of the first transistor are respectively connected to the driving unit, the emitter of the first transistor is connected to one end of the first resistor, and the other end of the first resistor is connected to the power module;

The base and collector of the second transistor are respectively connected to the driving unit, the emitter of the second transistor is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

One end of the third resistor is connected to the collector of the first transistor, and the other end of the third resistor is connected to the power module;

One end of the fourth resistor is connected to the collector of the second transistor, and the other end of the fourth resistor is connected to the power module.

Optionally, in the gate drive circuit, the opening branch includes: a first transistor and a first resistor; the closing branch includes: a second transistor and a second resistor; the first heating branch includes: a third transistor and a third resistor; the second heating branch includes: a fourth transistor and a fourth resistor; wherein,

The base of the third triode is connected to the driving unit, the collector of the third triode is connected to the collector of the first triode, the emitter of the third triode is connected to one end of the third resistor, and the other end of the third resistor is connected to the power module;

The base of the fourth transistor is connected to the driving unit, the collector of the fourth transistor is connected to the collector of the second transistor, the emitter of the fourth transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to the power module.

Optionally, in the gate drive circuit, the drive unit includes: a first drive sub-unit and a second drive sub-unit, and the first drive sub-unit and the second drive sub-unit are respectively connected to the micro control unit.

The collector of the first transistor is connected to the first driving sub-unit, the base of the first transistor is connected to the second driving sub-unit, the emitter of the first transistor is connected to one end of the first resistor, and the other end of the first resistor is connected to the power module;

The collector of the second triode is connected to the first driving subunit, the base of the second triode is connected to the second driving subunit, the emitter of the second triode is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

The collector of the second transistor is connected to the first driving subunit, and the second transistor The base of the second transistor is connected to the second driving sub-unit, the emitter of the second transistor is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

The collector of the third triode is connected to the collector of the first triode, the base of the third triode is connected to the second driving sub-unit, the emitter of the third triode is connected to one end of the third resistor, and the other end of the third resistor is connected to the power module;

The collector of the fourth transistor is connected to the collector of the second transistor, the base of the fourth transistor is connected to the second driving subunit, the emitter of the fourth transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to the power module.

Optionally, in the gate drive circuit, the resistance of the second resistor is greater than the resistance of the first resistor.

Optionally, in the gate drive circuit, the resistance of the third resistor is greater than the resistance of the first resistor and the second resistor; the resistance of the fourth resistor is greater than the resistance of the first resistor and the second resistor; and the resistance of the fourth resistor is greater than the resistance of the third resistor.

Optionally, in the gate drive circuit, the first transistor, the second transistor, the third transistor and the fourth transistor are all NPN transistors.

In the second aspect, an embodiment of the present application further provides a vehicle, comprising: a power battery, an inverter and the gate drive circuit, wherein the inverter is arranged at the rear stage of the gate drive circuit, wherein the inverter comprises: a power module, and the power battery is arranged close to the power module to obtain thermal energy from the power module.

In a third aspect, an embodiment of the present application further provides an active heating control method for a gate drive circuit, comprising:

Determine whether the vehicle enters a heating condition or a normal driving condition;

If the vehicle enters the heating condition, the microcontroller unit of the gate drive circuit is used to send a first control signal to the drive unit of the gate drive circuit; according to the first control signal, the drive unit of the gate drive circuit is used to send a heating drive signal to the first heating branch and the second heating branch of the gate drive circuit; the first heating branch and the second heating branch are used to control the opening and closing of the power module in the inverter of the vehicle, and at the same time, the power module is driven to heat the power battery of the vehicle;

If the vehicle enters a normal driving condition, the microcontroller unit of the gate drive circuit sends a second control signal to the drive unit of the gate drive circuit; according to the second control signal, the microcontroller unit of the gate drive circuit sends a second control signal to the drive unit of the gate drive circuit; The driving unit of the gate driving circuit sends a normal driving signal to the opening branch and the closing branch of the gate driving circuit; the opening branch and the closing branch are used to control the opening and closing of the power module in the inverter of the vehicle.

The technical solution of this application has at least the following advantages:

The present application introduces a first heating branch and a second heating branch into the gate drive circuit. In the heating condition, the driving unit receives the first control signal output by the microcontroller unit, sends a heating driving signal to the first heating branch and the second heating branch to control the opening and closing of the power module, and drives the power module to heat the vehicle's power battery; in the normal driving condition, the driving unit receives the second control signal output by the microcontroller unit, and sends a normal driving signal to the opening branch and the closing branch to control the opening and closing of the power module. The present application uses the first heating branch and the second heating branch to extend the opening time and the closing time of the power module in the heating condition, increases the switching loss of the inverter, improves the rate of active electric drive heating of the power battery of the electric vehicle in a low temperature environment, optimizes the effect of active electric drive heating of the power battery, and solves the problem of low rate and effect of active electric drive heating of the power battery of the electric vehicle in a low temperature environment.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of the structure of a gate drive circuit according to a first embodiment of the present invention;

2 is a control program flow chart of an active heating control method for a gate drive circuit according to a first embodiment of the present invention;

3 is a schematic diagram of the structure of a gate drive circuit according to a second embodiment of the present invention;

4 is a control program flow chart of an active heating control method for a gate drive circuit according to a second embodiment of the present invention;

5 is a schematic diagram of the structure of a gate drive circuit according to a third embodiment of the present invention;

6 is a schematic diagram of the structure of a gate drive circuit according to a fourth embodiment of the present invention;

The reference numerals are described as follows:
10-micro control unit, 20-driving unit, 21-first driving sub-unit, 22-second driving sub-unit,
31 - opening branch, 32 - closing branch, 33 - first heating branch, 34 - second heating branch.

Detailed ways

The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it 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 it can be indirectly connected through an intermediate medium, it can also be the internal connection of two components, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

The inventors found that under the same working conditions, the motor stator's heating power encountered a bottleneck due to the limitation of the maximum temperature rise value, but the heating power of the inverter still has great potential for improvement. The inventors found that the loss of the inverter is mainly caused by the power module, and the losses mainly include: switching loss and conduction loss. When other conditions such as voltage and current are the same, the switching loss of the inverter depends on the length of the on-time and off-time. The longer the on-time and off-time, the greater the loss. The on-time and off-time of the inverter's heating power mainly depend on the previous gate. The design of the pole drive circuit.

Based on this, the present invention provides a variety of gate drive circuits, as detailed in the following embodiments.

Embodiment 1

The first embodiment of the present application provides a gate drive circuit, please refer to FIG1, FIG1 is a schematic diagram of the structure of the gate drive circuit of the first embodiment of the present invention, the gate drive circuit includes: a micro control unit (MCU) 10, a drive unit 20, an opening branch 31, a closing branch 32, a first heating branch 33 and a second heating branch 34, the drive unit 20 is connected to the micro control unit 10, the opening branch 31 and the first heating branch 33 are connected in parallel, and the closing branch 32 and the second heating branch 34 are connected in parallel. One end of the parallel opening branch 31 and the first heating branch 33, and one end of the parallel closing branch 32 and the second heating branch 34 are respectively connected to the drive unit 20, and the other end of the parallel opening branch 31 and the first heating branch 33, and the other end of the parallel closing branch 32 and the second heating branch 34 are all connected to the power module in the inverter of the subsequent circuit.

In this embodiment, the inverter includes a power module, and the power module may include multiple power switch tubes, and the multiple power switch tubes may constitute a full-bridge power module. One end of the gate-source capacitance (MOS junction capacitance) C is connected to the gate G of the power switch tube, and the other end is connected to the source S of the power switch tube.

Furthermore, the opening branch 31 includes: a first transistor Q1 and a first resistor R1; the closing branch 32 includes: a second transistor Q2 and a second resistor R2; the first heating branch 33 includes: a third resistor R3; the second heating branch 34 includes: a fourth resistor R4.

The base and collector of the first transistor Q1 are connected to the driving unit 20 respectively, the emitter of the first transistor Q1 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the gate of the power switch tube in the subsequent inverter;

The base and collector of the second transistor Q2 are respectively connected to the driving unit 20, the emitter of the second transistor Q2 is connected to one end of the second resistor R2, and the other end of the second resistor R2 is connected to the gate of the power switch tube;

One end of the third resistor R3 is connected in parallel with the collector of the first transistor Q1 and then connected to the driving unit 20, and the other end of the third resistor R3 is connected to the gate of the power switch tube;

One end of the fourth resistor R4 is connected to the collector of the second transistor Q2 in parallel and then connected to the driving unit 20 , and the other end of the fourth resistor R4 is connected to the gate of the power switch tube.

Preferably, the resistance of the second resistor R2 is greater than the resistance of the first resistor R1.

Preferably, the resistance of the third resistor R3 is greater than the resistance of the first resistor R1 and the second resistor R2; the resistance of the fourth resistor R4 is greater than the resistance of the first resistor R1 and the second resistor R2.

Furthermore, the resistance of the fourth resistor R4 is greater than the resistance of the third resistor R3.

In this embodiment, the resistance value of the first resistor R1 can be selected in the range of 3Ω to 18Ω, and the resistance value of the second resistor R2 can be selected in the range of 6Ω to 21Ω.

Furthermore, the first transistor Q1 and the second transistor Q2 are both NPN transistors.

In this embodiment, the gate drive circuit is configured as follows:

In the heating condition, the microcontroller unit 10 sends a first control signal to the drive unit 20, and the first control signal may be a multi-channel control signal. The drive unit 20 receives the first control signal output by the microcontroller unit 10, and according to the first control signal, turns off the first transistor Q1 of the opening branch 31 and turns off the second transistor Q2 of the closing branch 32, and sends a heating drive signal to the first heating branch 33 and the second heating branch 34 to control the opening and closing of the power module. At this time, the first heating branch 33 and the second heating branch 34 extend the opening time and the closing time of the power module, thereby generating switching loss, and using this part of the switching loss to heat the power battery of the vehicle;

In normal driving conditions, the microcontroller unit 10 sends a second control signal to the drive unit 20, and the second control signal can be a multi-channel control signal. The drive unit 20 receives the second control signal output by the microcontroller unit 10, and according to the second control signal, turns on the first transistor Q1 of the turn-on branch 31 and turns on the second transistor Q2 of the turn-off branch 32, and sends a normal driving signal to the turn-on branch 31 and the turn-off branch 32 as well as the first heating branch 33 and the second heating branch 34 to control the turning on and off of the power module. At this time, the first resistor R1 of the turn-on branch 31 and the third resistor R3 of the first heating branch 33 are connected in parallel as a turn-on resistor Ron with a smaller resistance, and the second resistor R2 of the turn-off branch 32 and the fourth resistor R4 of the second heating branch 34 are connected in parallel as a turn-off resistor Roff with a smaller resistance.

In this embodiment, the first resistor R1 and the third resistor R3 connected in parallel serve as a normal turn-on resistor Ron; the second resistor R2 and the fourth resistor R4 connected in parallel serve as a normal turn-off resistor Roff; the third resistor R3 serves as a delayed turn-on resistor Ron; and the fourth resistor R4 serves as a delayed turn-off resistor Roff.

Based on the same inventive concept, an embodiment of the present application also provides a vehicle, comprising: a power battery, an inverter and the gate drive circuit, wherein the inverter is arranged at the rear stage of the gate drive circuit, wherein the inverter comprises: a power module, and the power battery is arranged close to the power module to obtain the thermal energy of the power module.

Based on the same inventive concept, the embodiment of the present application further provides an active heating control method for a gate drive circuit. Referring to FIG. 2 , FIG. 2 is a control program flow chart of the active heating control method for a gate drive circuit according to the first embodiment of the present invention. The active heating control method for a gate drive circuit includes:

First, determine whether the vehicle is in a heating condition or a normal driving condition;

If the vehicle enters the heating condition, the microcontroller unit 10 of the gate drive circuit sends a first control signal to the drive unit 20 of the gate drive circuit; according to the first control signal, the first transistor Q1 of the opening branch 31 is turned off and the second transistor Q2 of the closing branch 32 is turned off, and the drive unit 20 of the gate drive circuit sends a heating drive signal to the first heating branch 33 and the second heating branch 34 of the gate drive circuit; the first heating branch 33 and the second heating branch 34 are used to control the delayed opening and delayed closing of the power module in the inverter of the vehicle, and at the same time, the power module is driven to heat the power battery of the vehicle;

If the vehicle enters a normal driving condition, the microcontroller unit 10 of the gate drive circuit is used to send a second control signal to the drive unit 20 of the gate drive circuit; according to the second control signal, the first transistor Q1 of the opening branch 31 is turned on and the second transistor Q2 of the closing branch 32 is turned on, and the drive unit 20 of the gate drive circuit is used to send a normal drive signal to the opening branch 31 and the closing branch 32 as well as the first heating branch 33 and the second heating branch 34 to control the opening and closing of the power module. At this time, the first resistor R1 of the opening branch 31 and the third resistor R3 of the first heating branch 33 are connected in parallel as an opening resistor Ron with a smaller resistance value, and the second resistor R2 of the closing branch 32 and the fourth resistor R4 of the second heating branch 34 are connected in parallel as an off resistor Roff with a smaller resistance value.

After research, the inventors found that the on-resistance Ron has a greater impact on the switching loss of the inverter than the off-resistance Roff. Under the condition of keeping the off-resistance Roff unchanged, the switching loss of the inverter can be increased to 143.24% by changing the resistance value of the on-resistance Ron. This is sufficient to prove that the gate drive circuit provided by the present invention can provide sufficient heat energy for the power battery of the vehicle in a short time in a low temperature environment.

Embodiment 2

The second embodiment of the present application provides a gate drive circuit, please refer to FIG3, FIG3 is a schematic diagram of the structure of the gate drive circuit of the second embodiment of the present invention, the gate drive circuit includes: a micro control unit (MCU) 10, a drive unit 20, an opening branch 31, a closing branch 32, a first heating branch 33 and a second heating branch 34, the drive unit 20 is connected to the micro control unit 10, the opening branch 31 and the first heating branch 33 are connected in parallel, and the closing branch 32 and the second heating branch 34 are connected in parallel. One end of the parallel opening branch 31 and the first heating branch 33, and one end of the parallel closing branch 32 and the second heating branch 34 are respectively connected to the drive unit 20, and the other end of the parallel opening branch 31 and the first heating branch 33, and the other end of the parallel closing branch 32 and the second heating branch 34 are connected to the power module in the inverter of the subsequent circuit.

Among them, the opening branch 31 includes: a first transistor Q1 and a first resistor R1; the closing branch 32 includes: a second transistor Q2 and a second resistor R2; the first heating branch 33 includes: a third transistor Q3 and a third resistor R3; the second heating branch 34 includes: a fourth transistor Q4 and a fourth resistor R4.

Specifically, the base and collector of the first transistor Q1 are connected to the driving unit 20 respectively, the emitter of the first transistor Q1 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the gate of the power switch tube;

The base of the third triode Q3 is connected to the driving unit 20, the collector of the third triode Q3 is connected to the collector of the first triode Q1, the emitter of the third triode Q3 is connected to one end of the third resistor R3, and the other end of the third resistor R3 is connected to the gate of the power switch tube;

The base of the fourth transistor Q4 is connected to the driving unit 20, the collector of the fourth transistor Q4 is connected to the collector of the second transistor Q2, the emitter of the fourth transistor Q4 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is connected to the gate of the power switch tube.

Further, the first transistor Q1, the second transistor Q2, the third transistor Q3 and the fourth transistor Q4 are all NPN transistors.

Based on the same inventive concept, the embodiment of the present application further provides an active heating control method for a gate drive circuit. Referring to FIG. 4 , FIG. 4 is a control program flow chart of the active heating control method for a gate drive circuit according to the second embodiment of the present invention. The active heating control method for a gate drive circuit includes:

If the vehicle enters the heating condition, the microcontroller unit 10 of the gate drive circuit sends a first control signal to the drive unit 20 of the gate drive circuit; according to the first control signal, the first transistor Q1 of the opening branch 31 is turned off, the second transistor Q2 of the closing branch 32 is turned off, and the third transistor Q3 of the first heating branch 33 is turned on, and the fourth transistor Q4 of the fourth heating branch 34 is turned on. At this time, the opening branch 31 and the closing branch 32 are both in the disconnected state, and the drive unit 20 of the gate drive circuit sends a heating drive signal to the first heating branch 33 and the second heating branch 34 of the gate drive circuit; the first heating branch 33 and the second heating branch 34 are used to control the opening and closing of the power module in the inverter of the vehicle, and at the same time, the power module is driven to heat the power battery of the vehicle;

If the vehicle enters a normal driving condition, the microcontroller unit 10 of the gate drive circuit sends a second control signal to the drive unit 20 of the gate drive circuit; according to the second control signal, the first transistor Q1 of the opening branch 31 is turned on, the second transistor Q2 of the closing branch 32 is turned on, and the third transistor Q3 of the first heating branch 33 is turned off, and the fourth transistor Q4 of the fourth heating branch 34 is turned off. At this time, the first heating branch 33 and the second heating branch 34 are both in the disconnected state, and the drive unit 20 of the gate drive circuit sends a normal drive signal to the opening branch 31 and the closing branch 32 to control the power mode. Block opening and closing.

In this embodiment, the first resistor R1 is used as a normal on-resistance Ron; the third resistor R3 can be used as a delayed on-resistance Ron; the second resistor R2 is used as a normal off-resistance Roff; and the fourth resistor R4 can be used as a delayed off-resistance Roff.

Embodiment 3

The third embodiment of the present application provides a gate drive circuit, please refer to Figure 5, Figure 5 is a schematic diagram of the structure of the gate drive circuit of the third embodiment of the present invention, the gate drive circuit includes: a micro control unit (MCU) 10, a drive unit 20, an opening branch 31, a closing branch 32, a first heating branch 33 and a second heating branch 34, the drive unit 20 is connected to the micro control unit 10, the opening branch 31 and the first heating branch 33 are connected in parallel, and the closing branch 32 and the second heating branch 34 are connected in parallel. One end of the parallel opening branch 31 and the first heating branch 33, and one end of the parallel closing branch 32 and the second heating branch 34 are respectively connected to the drive unit 20, and the other end of the parallel opening branch 31 and the first heating branch 33, and the other end of the parallel closing branch 32 and the second heating branch 34 are all connected to the power module in the inverter of the subsequent circuit.

The driving unit 20 includes: a first driving subunit 21 and a second driving subunit 22, and the first driving subunit 21 and the second driving subunit 22 are respectively connected to the micro control unit 10. The first driving subunit 21 is used to control the opening and closing of the power module, and the second driving subunit 22 is used to control the opening and closing of the first transistor Q1 of the opening branch 31, and the opening and closing of the second transistor Q2 of the closing branch 32.

Further, the opening branch 31 includes: a first transistor Q1 and a first resistor R1; the closing branch 32 includes: a second transistor Q2 and a second resistor R2; the first heating branch 33 includes: a third resistor R3; the second heating branch 34 includes: a fourth resistor R4; wherein,

The collector of the first transistor Q1 is connected to the first driving subunit 21, the base of the first transistor is connected to the second driving subunit 22, the emitter of the first transistor Q1 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the gate of the power switch tube;

The collector of the second transistor Q2 is connected to the first driving subunit 21, the base of the second transistor Q2 is connected to the second driving subunit 22, and the emitter of the second transistor Q2 is connected to the first driving subunit 21. The emitter is connected to one end of the second resistor R2, and the other end of the second resistor R2 is connected to the gate of the power switch tube;

One end of the third resistor R3 is connected to the collector of the first transistor Q1, and the other end of the third resistor R3 is connected to the gate of the power switch tube;

One end of the fourth resistor R4 is connected to the collector of the second transistor Q2, and the other end of the fourth resistor R4 is connected to the gate of the power switch tube.

Furthermore, both the first transistor Q1 and the second transistor Q2 are NPN transistors.

Based on the same inventive concept, an embodiment of the present application further provides an active heating control method for a gate drive circuit. Referring to FIG. 2 , the active heating control method for a gate drive circuit includes:

If the vehicle enters the heating condition, the microcontroller unit 10 of the gate drive circuit sends a first control signal to the first driver unit 21 and the second driver unit 22 of the gate drive circuit respectively; according to the first control signal, the second driver unit 22 controls the first transistor Q1 of the opening branch 31 to be turned off and the second transistor Q2 of the closing branch 32 to be turned off, and the first driver unit 21 sends a heating drive signal to the first heating branch 33 and the second heating branch 34 of the gate drive circuit; the first heating branch 33 and the second heating branch 34 are used to control the first transistor Q1 of the opening branch 31 to be turned off and the second transistor Q2 of the closing branch 32 to be turned off. The heating branch 34 controls the delayed opening and delayed closing of the power module in the inverter of the vehicle, and at the same time, drives the power module to heat the power battery of the vehicle;

If the vehicle enters a normal driving condition, the microcontroller unit 10 of the gate drive circuit is used to send a second control signal to the first driver unit 21 and the second driver unit 22 of the gate drive circuit respectively; according to the second control signal, the second driver unit 22 is used to control the first transistor Q1 of the opening branch 31 and the second transistor Q2 of the closing branch 32, and the first driver unit 21 of the gate drive circuit is used to send a normal drive signal to the opening branch 31 and the closing branch 32 as well as the first heating branch 33 and the second heating branch 34 to control the opening and closing of the power module. At this time, the first resistor R1 of the opening branch 31 and the third resistor R3 of the first heating branch 33 are connected in parallel as an opening resistor Ron with a smaller resistance value, and the second resistor R2 of the closing branch 32 and the fourth resistor R4 of the second heating branch 34 are connected in parallel as an off resistor Roff with a smaller resistance value.

Embodiment 4

The fourth embodiment of the present application provides a gate drive circuit, please refer to Figure 6, Figure 6 is a schematic diagram of the structure of the gate drive circuit of the fourth embodiment of the present invention, the gate drive circuit includes: a micro control unit (MCU) 10, a first driver unit 21, a second driver unit 22, an opening branch 31, a closing branch 32, a first heating branch 33 and a second heating branch 34, the first driver unit 21 and the second driver unit 22 are both connected to the micro control unit 10, the opening branch 31 and the first heating branch 33 are connected in parallel, and the closing branch 32 and the second heating branch 34 are connected in parallel. One end of the parallel opening branch 31 and the first heating branch 33, and one end of the parallel closing branch 32 and the second heating branch 34 are respectively connected to the first driver unit 21, and the other end of the parallel opening branch 31 and the first heating branch 33, and the other end of the parallel closing branch 32 and the second heating branch 34 are all connected to the power module in the inverter of the subsequent circuit.

Specifically, the collector of the first transistor Q1 is connected to the first driving subunit 21, the base of the first transistor Q1 is connected to the second driving subunit 22, and the first transistor The emitter of Q1 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the gate of the power switch tube;

The collector of the second transistor Q2 is connected to the first driving subunit 21, the base of the second transistor Q2 is connected to the second driving subunit 22, the emitter of the second transistor Q2 is connected to one end of the second resistor R2, and the other end of the second resistor R2 is connected to the gate of the power switch tube;

The collector of the third triode Q3 is connected to the collector of the first triode Q1, the base of the third triode Q3 is connected to the second driving subunit 22, the emitter of the third triode Q3 is connected to one end of the third resistor R3, and the other end of the third resistor R3 is connected to the gate of the power switch tube;

The collector of the fourth transistor Q4 is connected to the collector of the second transistor Q2, the base of the fourth transistor Q4 is connected to the second driving sub-unit 22, the emitter of the fourth transistor Q4 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is connected to the gate of the power switch tube.

Based on the same inventive concept, the embodiment of the present application further provides an active heating control method for a gate drive circuit. Referring to FIG. 4 , the active heating control method for a gate drive circuit includes:

If the vehicle enters the heating state, the microcontroller unit 10 of the gate drive circuit sends a first control signal to the first drive subunit 21 and the second drive subunit 22 of the gate drive circuit respectively. signal; according to the first control signal, the second driving subunit 22 is used to turn off the first transistor Q1 of the opening branch 31, turn off the second transistor Q2 of the closing branch 32, and turn on the third transistor Q3 of the first heating branch 33, and turn on the fourth transistor Q4 of the fourth heating branch 34. At this time, the opening branch 31 and the closing branch 32 are both in the disconnected state, and the first driving subunit 21 of the gate driving circuit is used to send a heating driving signal to the first heating branch 33 and the second heating branch 34 of the gate driving circuit; the first heating branch 33 and the second heating branch 34 are used to control the opening and closing of the power module in the inverter of the vehicle, and at the same time, the power module is driven to heat the power battery of the vehicle;

If the vehicle enters a normal driving condition, the microcontroller unit 10 of the gate drive circuit is used to send a second control signal to the first driver subunit 21 and the second driver subunit 22 of the gate drive circuit respectively; according to the second control signal, the second driver subunit 22 is used to open the first transistor Q1 of the opening branch 31, open the second transistor Q2 of the closing branch 32, and close the third transistor Q3 of the first heating branch 33, and close the fourth transistor Q4 of the fourth heating branch 34. At this time, the first heating branch 33 and the second heating branch 34 are both in the disconnected state, and the first driver subunit 21 of the gate drive circuit is used to send a normal drive signal to the opening branch 31 and the closing branch 32 to control the opening and closing of the power module.

In the present application, by introducing the first heating branch 33 and the second heating branch 34 into the gate drive circuit, in the heating condition, the driving unit 20 receives the first control signal output by the microcontroller unit 10, sends a heating driving signal to the first heating branch 33 and the second heating branch 34 to control the delayed opening and delayed closing of the power module, and drives the power module to heat the power battery of the vehicle. The present application utilizes the first heating branch 33 and the second heating branch 34 to extend the opening time and the closing time of the power module in the subsequent inverter, increase the switching loss of the inverter, improve the rate of active heating of the electric drive of the power battery of the electric vehicle in a low temperature environment, optimize the effect of active heating of the electric drive of the power battery, and solve the problem of low rate and effect of active heating of the electric drive of the power battery of the electric vehicle in a low temperature environment.

Obviously, the above embodiments are only examples for the purpose of clear explanation and are not intended to be limiting. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the protection scope of the invention of this application.

Claims

A gate drive circuit, characterized in that it comprises: a micro control unit, a drive unit, an opening branch, a closing branch, a first heating branch and a second heating branch, wherein the drive unit is connected to the micro control unit, the opening branch and the first heating branch are connected in parallel, the closing branch and the second heating branch are connected in parallel, one end of the opening branch and the first heating branch connected in parallel, and one end of the closing branch and the second heating branch connected in parallel are respectively connected to the drive unit, and the other end of the opening branch and the first heating branch connected in parallel, and the other end of the closing branch and the second heating branch connected in parallel are both connected to a power module in an inverter of a subsequent circuit;

Wherein, the gate drive circuit is configured as follows:

In the heating condition, the driving unit receives the first control signal output by the microcontroller unit, and sends a heating driving signal to the first heating branch and the second heating branch according to the first control signal to control the opening and closing of the power module, and drives the power module to heat the power battery of the vehicle;

In a normal driving condition, the driving unit receives a second control signal output by the microcontroller unit, and sends a normal driving signal to the on branch and the off branch according to the second control signal to control the on and off of the power module.
The gate drive circuit according to claim 1 is characterized in that the opening branch comprises: a first transistor and a first resistor; the closing branch comprises: a second transistor and a second resistor; the first heating branch comprises: a third resistor; the second heating branch comprises: a fourth resistor; wherein,

The base and collector of the first transistor are respectively connected to the driving unit, the emitter of the first transistor is connected to one end of the first resistor, and the other end of the first resistor is connected to the power module;

The base and collector of the second transistor are respectively connected to the driving unit. The emitter of the diode is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

One end of the third resistor is connected to the collector of the first transistor, and the other end of the third resistor is connected to the power module;

One end of the fourth resistor is connected to the collector of the second transistor, and the other end of the fourth resistor is connected to the power module.
The gate drive circuit according to claim 1 is characterized in that the opening branch comprises: a first transistor and a first resistor; the closing branch comprises: a second transistor and a second resistor; the first heating branch comprises: a third transistor and a third resistor; the second heating branch comprises: a fourth transistor and a fourth resistor; wherein,

The base and collector of the first transistor are respectively connected to the driving unit, the emitter of the first transistor is connected to one end of the first resistor, and the other end of the first resistor is connected to the power module;

The base and collector of the second transistor are respectively connected to the driving unit, the emitter of the second transistor is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

The base of the third triode is connected to the driving unit, the collector of the third triode is connected to the collector of the first triode, the emitter of the third triode is connected to one end of the third resistor, and the other end of the third resistor is connected to the power module;

The base of the fourth transistor is connected to the driving unit, the collector of the fourth transistor is connected to the collector of the second transistor, the emitter of the fourth transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to the power module.
The gate drive circuit according to claim 1, characterized in that the drive unit comprises: a first drive sub-unit and a second drive sub-unit, and the first drive sub-unit and the second drive sub-unit are respectively connected to the micro control unit.
The gate drive circuit according to claim 4 is characterized in that the opening branch comprises: a first transistor and a first resistor; the closing branch comprises: a second transistor and a second resistor; the first heating branch comprises: a third resistor; the second heating branch comprises: a fourth resistor; wherein,

The collector of the first transistor is connected to the first driving sub-unit, the base of the first transistor is connected to the second driving sub-unit, the emitter of the first transistor is connected to one end of the first resistor, and the other end of the first resistor is connected to the power module;

The collector of the second triode is connected to the first driving subunit, the base of the second triode is connected to the second driving subunit, the emitter of the second triode is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

One end of the third resistor is connected to the collector of the first transistor, and the other end of the third resistor is connected to the power module;

One end of the fourth resistor is connected to the collector of the second transistor, and the other end of the fourth resistor is connected to the power module.
The gate drive circuit according to claim 4 is characterized in that the opening branch includes: a first transistor and a first resistor; the closing branch includes: a second transistor and a second resistor; the first heating branch includes: a third transistor and a third resistor; the second heating branch includes: a fourth transistor and a fourth resistor; wherein,

The collector of the first transistor is connected to the first driving sub-unit, the base of the first transistor is connected to the second driving sub-unit, the emitter of the first transistor is connected to one end of the first resistor, and the other end of the first resistor is connected to the power module;

The collector of the second triode is connected to the first driving subunit, the base of the second triode is connected to the second driving subunit, the emitter of the second triode is connected to one end of the second resistor, and the other end of the second resistor is connected to the power module;

The collector of the third transistor is connected to the collector of the first transistor. The base of the transistor is connected to the second driving sub-unit, the emitter of the third transistor is connected to one end of the third resistor, and the other end of the third resistor is connected to the power module;

The collector of the fourth transistor is connected to the collector of the second transistor, the base of the fourth transistor is connected to the second driving subunit, the emitter of the fourth transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to the power module.
The gate drive circuit according to any one of claims 2-3 and 5-6 is characterized in that the resistance of the second resistor is greater than the resistance of the first resistor.
The gate drive circuit according to any one of claims 2-3 and 5-6 is characterized in that the resistance of the third resistor is greater than the resistance of the first resistor and the second resistor; the resistance of the fourth resistor is greater than the resistance of the first resistor and the second resistor; the resistance of the fourth resistor is greater than the resistance of the third resistor.
The gate drive circuit according to claim 3 or 6, characterized in that the first transistor, the second transistor, the third transistor and the fourth transistor are all NPN transistors.
A vehicle, characterized in that it comprises: a power battery, an inverter and a gate drive circuit as described in any one of claims 1 to 9, wherein the inverter is arranged at the rear stage of the gate drive circuit, wherein the inverter comprises: a power module, and the power battery is arranged close to the power module to obtain heat energy from the power module.
An active heating control method for a gate drive circuit, characterized by comprising:

Determine whether the vehicle enters a heating condition or a normal driving condition;

If the vehicle enters the heating condition, a microcontroller unit of the gate drive circuit according to any one of claims 1 to 9 is used to send a first control signal to a drive unit of the gate drive circuit; according to the first control signal, a heating drive signal is sent to a first heating branch and a second heating branch of the gate drive circuit by the drive unit of the gate drive circuit; the first heating branch and the second heating branch are used to control the opening and closing of a power module in an inverter of the vehicle, and at the same time, Driving the power module to heat a power battery of the vehicle;

If the vehicle enters a normal driving condition, the microcontroller unit of the gate drive circuit is used to send a second control signal to the drive unit of the gate drive circuit; according to the second control signal, the drive unit of the gate drive circuit is used to send a normal drive signal to the opening branch and the closing branch of the gate drive circuit; the opening branch and the closing branch are used to control the opening and closing of the power module in the inverter of the vehicle.