Realize drive circuit with interlocking and non-interlocking drive signals

Abstract

A driving circuit capable of realizing interlocking and non-interlocking of driving signals comprises: a control unit, a driving signal conversion unit and a driving signal output unit connected in sequence, wherein: the driving signal conversion unit is composed of two parallel level conversion units and two triodes, and the driving signal output unit is composed of two parallel driving output modules, wherein: the control unit is connected to the driving signal conversion unit, and outputs a switch signal and a driving signal to the driving signal conversion module according to a detected torque signal, a speed signal and an active discharge signal sent by a vehicle controller, and the outputs of the two parallel level conversion units in the driving signal conversion unit are combined and added and then outputted as IGBT driving switch signals to the two driving output modules in the driving signal output unit. The present invention controls the operation of a Schmitt trigger or a level conversion chip by controlling a chip to output high and low levels to two triodes, thereby controlling the output of interlocking driving signals and non-interlocking driving signals of the driving circuit, and achieving the effect of controlling the interlocking and non-interlocking of the driving circuit.

Description

Technical Field

[0001] The present invention relates to a technology in the field of IGBT drive circuits, in particular to a drive circuit for realizing interlocking and non-interlocking of drive signals. Background Art

[0002] At present, there is a discharge scheme in the controller of new energy vehicles that discharges through the IGBT bridge arm directly. This scheme saves structural space and reduces costs without using external discharge resistors. However, this discharge circuit has a disadvantage that the drive circuit that needs to discharge through the bridge arm cannot be interlocked, which makes it easy for the bridge arm to damage the controller during normal operation. Once the discharge circuit is damaged, the active discharge function cannot be realized. The existing drive circuit driving schemes are mainly two schemes: drive signal interlocking scheme and drive signal non-interlocking scheme. The two drive schemes cannot realize the switching interlocking and non-interlocking functions on the same drive circuit. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention proposes a driving circuit for realizing interlocking and non-interlocking of driving signals, and controls the output of interlocking driving signals and non-interlocking driving signals of the driving circuit by means of a control unit to start / shut down the first and second level conversion units respectively, thereby achieving the effect of controlling the interlocking and non-interlocking of the driving circuit.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention comprises: a control unit, a drive signal conversion unit and a drive signal output unit which are connected in sequence, wherein: the drive signal conversion unit is composed of two parallel level conversion units and two triodes, and the drive signal output unit is composed of two parallel drive output modules, wherein: the control unit is connected to the drive signal conversion unit, and outputs a switch signal and a drive signal to the drive signal conversion module according to a detected torque signal, a speed signal and an active discharge signal sent by a received vehicle controller, and the outputs of the two parallel level conversion units in the drive signal conversion unit are combined and added and then output as IGBT drive switch signals to the two drive output modules in the drive signal output unit.

[0006] The merging and adding means that: the first output terminal and the second output terminal of the first level conversion unit and the second level conversion unit are added respectively as the first and second inputs of the first driving output module; the third output terminal and the fourth output terminal of the first level conversion unit and the second level conversion unit are added respectively as the first and second inputs of the second driving output module.

[0007] The level conversion unit adopts but is not limited to a Schmitt trigger.

[0008] Technical Effects

[0009] Compared with the prior art, the present invention controls the operation of the Schmitt trigger or the level conversion chip by controlling the chip to output high and low levels to the first transistor and the second transistor, thereby controlling the output of the interlocking drive signal and the non-interlocking drive signal of the drive circuit, thereby achieving the effect of controlling the interlocking and non-interlocking of the drive circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the system structure of the present invention;

[0011] Figure 2a and Figure 2b This is a circuit diagram of this embodiment;

[0012] Figure 3 This is a block diagram of the interlocking drive operation of the present invention;

[0013] Figure 4 This is a non-interlocking drive operation block diagram of the present invention;

[0014] In the figure: control unit 1, first transistor 2, second transistor 3, first Schmitt trigger 4, second Schmitt trigger 5, first drive circuit 6, second drive circuit 7, first resistor 8, second resistor 9, third resistor 10, fourth resistor 11, fifth resistor 12, sixth resistor 13, seventh resistor 14, eighth resistor 15, first capacitor 16, second capacitor 17, third capacitor 18, fourth capacitor 19, fifth capacitor 20, sixth capacitor 21, level conversion circuit 22. DETAILED DESCRIPTION

[0015] like Figure 1 , Figure 2a and Figure 2bAs shown, a driving circuit for realizing interlocking and non-interlocking of driving signals involved in this embodiment comprises: a control unit 1, a first transistor 2, a second transistor 3, a first Schmitt trigger 4, a second Schmitt trigger 5, a first driving circuit 6 and a second driving circuit 7, wherein: the PWM port of the control unit 1 is respectively connected to the A port of the first Schmitt trigger 4 and the second Schmitt trigger 5; the base, collector and emitter of the first transistor 2 are respectively connected to the I / O port, VCC and the VCC port of the first Schmitt trigger 4 of the control unit 1; the base, collector and emitter of the second transistor 3 are respectively connected to the I / O port, VCC and the VCC port of the control unit 1 VCC is connected to the VCC port of the second Schmitt trigger 5; the first Y port of the first Schmitt trigger 4 is respectively connected to the first Y port of the second Schmitt trigger 5 and the IN+ port of the first drive circuit 6; the second Y port of the first Schmitt trigger 4 is respectively connected to the second Y port of the second Schmitt trigger 5 and the IN- of the first drive circuit 6; the third Y port of the second Schmitt trigger 5 is respectively connected to the third Y port of the first Schmitt trigger 4 and the IN+ port of the second drive circuit 7; the fourth Y port of the second Schmitt trigger 5 is respectively connected to the fourth Y port of the first Schmitt trigger 4 and the IN- port of the second drive circuit 7.

[0016] A second resistor 9 is connected in series between the base of the first transistor 2 and the PWM port of the control unit 1 , a first capacitor 16 is connected in parallel between the second resistor 9 and the base of the first transistor 3 , and the other end of the first capacitor 16 is connected to GND.

[0017] A fifth resistor 12 is connected in series between the base of the second transistor 3 and the PWM port of the control unit 1 , a fourth capacitor 19 is connected in parallel between the fifth resistor 12 and the base of the second transistor 3 , and the other end of the fourth capacitor 19 is connected to GND.

[0018] A first resistor 8 is connected in series between the VCC port of the first Schmitt trigger 4 and the emitter of the first transistor 2 .

[0019] A third resistor 10 is connected in series between the first A port of the first Schmitt trigger 4 and the IN+ port of the first drive circuit 6, and a second capacitor 17 is connected in parallel between the third resistor 10 and the IN+ port of the first drive circuit 6, and the other end of the second capacitor 17 is connected to GND.

[0020] A fourth resistor 11 is connected in series between the second A port of the first Schmitt trigger 4 and the IN- port of the first drive circuit 6, a third capacitor 18 is connected in parallel between the fourth resistor 11 and IN- of the first drive circuit 6, and the other end of the third capacitor 18 is connected to GND.

[0021] A sixth resistor 13 is connected in series between the VCC port of the second Schmitt trigger 5 and the emitter of the second transistor 7 .

[0022] A seventh resistor 14 is connected in series between the third A port of the second Schmitt trigger 5 and IN+ of the second drive circuit 7, a fifth capacitor 20 is connected in parallel between the seventh resistor 14 and IN+ of the second drive circuit 7, and the other end of the fifth capacitor 20 is connected to GND.

[0023] An eighth resistor 15 is connected in series between the fourth A port of the second Schmitt trigger 5 and the IN-port of the second drive circuit 7, a sixth capacitor 21 is connected in parallel between the eighth resistor 15 and the IN-port of the second drive circuit 7, and the other end of the sixth capacitor 21 is connected to GND.

[0024] This embodiment relates to a control method of the above device, which specifically includes:

[0025] like Figure 3 As shown, when the circuit is working normally, the drive circuit needs to be interlocked to prevent direct damage to the IGBT. The control unit receives the normal working signal from the vehicle controller, outputs a high level to the first transistor, outputs a low level to the second transistor, and outputs a PWM control signal to the first Schmitt trigger and the second Schmitt trigger respectively; the first transistor is turned on when receiving a high level signal, and supplies 5V voltage to the first Schmitt trigger, at which time the first Schmitt trigger works normally; the second transistor is turned off when receiving a low level and has no output, at which time the second Schmitt trigger does not work; the PWM control signal output by the control unit passes through the first Schmitt trigger to form a drive interlock signal to control the operation of the drive circuit;

[0026] like Figure 4 As shown, when the circuit needs direct discharge, the drive circuit needs to release the interlock signal. The control unit receives the active discharge signal from the vehicle controller, and judges the torque signal and the speed signal. When the torque signal and the speed signal meet the requirements of active discharge, the control unit outputs a low level to the first transistor, a high level to the second transistor, and outputs a PWM control signal to the first Schmitt trigger and the second Schmitt trigger respectively; the second transistor is turned on after receiving the high level signal, and the 5V voltage is supplied to the second Schmitt trigger, and the second Schmitt trigger works normally at this time; the first transistor is turned off after receiving the low level and has no output, and the first Schmitt trigger does not work at this time; the PWM control signal output by the control unit passes through the second Schmitt trigger to form a non-interlocked drive signal to control the drive circuit to work, and the drive circuit can perform direct discharge.

[0027] The Schmitt trigger can also be replaced by a level conversion chip, and its primary power supply voltage can be 3.3 V or 5 V. According to the output voltage of the control chip and the input voltage requirement of the driver chip, the conversion between levels can be achieved through the level conversion chip or the Schmitt trigger.

[0028] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. A control method for a drive circuit that realizes interlocking and non-interlocking of drive signals, characterized in that: The driving circuit comprises: a control unit, a driving signal conversion unit and a driving signal output unit connected in sequence, wherein: the driving signal conversion unit is composed of two parallel level conversion units and two triodes, and the driving signal output unit is composed of two parallel driving output modules, wherein: the control unit is connected to the driving signal conversion unit, and outputs a switch signal and a driving signal to the driving signal conversion module according to a detected torque signal, a speed signal and an active discharge signal sent by a vehicle controller, and the outputs of the two parallel level conversion units in the driving signal conversion unit are combined and added, and then outputted as IGBT driving switch signals to the two driving output modules in the driving signal output unit; The merging and adding means that: the first output terminal and the second output terminal of the first level conversion unit and the second level conversion unit are added respectively as the first and second inputs of the first driving output module; the third output terminal and the fourth output terminal of the first level conversion unit and the second level conversion unit are added respectively as the first and second inputs of the second driving output module; The level conversion unit adopts a Schmitt trigger; The control method is as follows: when the circuit is working normally, the drive circuit needs to be interlocked to prevent the IGBT from being damaged by direct conduction, and the control unit outputs a high level to the first transistor, a low level to the second transistor, and outputs a PWM control signal to the first Schmitt trigger and the second Schmitt trigger respectively; the first transistor is turned on when receiving a high level signal, and supplies 5V voltage to the first Schmitt trigger, and the first Schmitt trigger works normally at this time; the second transistor is turned off when receiving a low level and has no output, and the second Schmitt trigger does not work at this time; the PWM control signal output by the control unit passes through the first Schmitt trigger to form a drive interlock signal to control the operation of the drive circuit; When the circuit needs direct discharge, the control chip receives the active discharge signal from the vehicle controller and judges the speed detection signal and the torque detection signal. When the speed and the torque are within the range allowed for active discharge, the drive circuit needs to release the interlocking signal, and the control unit outputs a low level to the first transistor, a high level to the second transistor, and outputs a PWM control signal to the first Schmitt trigger and the second Schmitt trigger respectively; the second transistor is turned on after receiving the high level signal, and supplies 5V voltage to the second Schmitt trigger, and the second Schmitt trigger works normally at this time; the first transistor is turned off after receiving the low level and has no output, and the first Schmitt trigger does not work at this time; the PWM control signal output by the control unit passes through the second Schmitt trigger to form a non-interlocked drive signal to control the drive circuit to work, and the drive circuit performs direct discharge.

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