A photoelectric conversion device for IGBT drive signal transmission

Abstract

The present invention discloses a photoelectric conversion device for IGBT drive signal transmission, the device includes a power supply filter circuit, a voltage conversion circuit, a pulse signal conversion circuit, and a fault signal conversion circuit, the power supply filter circuit is respectively connected to the power supply ends of the voltage conversion circuit, the pulse signal conversion circuit, and the fault signal conversion circuit, the voltage conversion circuit is connected to the low voltage power supply end of the pulse signal conversion circuit after reducing the voltage, and the pulse signal conversion circuit is sent to the IGBT drive circuit after inverting and shaping the optical pulse signal emitted by the controller. The present invention solves the problem that the current drive pulse signal is transmitted using a transmission line, and during the transmission process, the interference source will interfere with the pulse signal through the parasitic capacitance and parasitic inductance of the transmission line, which may cause the IGBT to be mis-conducted, causing a short circuit and damaging the device.

Description

Technical Field

[0001] The present invention relates to the technical field of IGBT drive signal transmission, and in particular to a photoelectric conversion device for IGBT drive signal transmission. Background Art

[0002] With the development of IGBT technology, IGBT has been widely used as a mainstream power device in the fields of industry, power grid, transportation, aerospace, etc. The driving signal is sent by the controller to drive the IGBT to work. During the transmission of the driving pulse signal, if the transmission line is long, the interference source will interfere with the pulse signal through the parasitic capacitance and parasitic inductance of the transmission line, which may cause the IGBT to be mis-conducted, resulting in a short circuit and damage to the device. Summary of the invention

[0003] In response to the above technical problems, the present invention provides a photoelectric conversion device for IGBT drive signal transmission, which can avoid the current drive pulse signal being transmitted via a transmission line. During the transmission process, the interference source will interfere with the pulse signal through the parasitic capacitance and parasitic inductance of the transmission line, which may cause the IGBT to be misconnected, resulting in a short circuit and damage to the device.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows:

[0005] A photoelectric conversion device for IGBT drive signal transmission includes a power supply filter circuit, a voltage conversion circuit, a pulse signal conversion circuit, and a fault signal conversion circuit. The power supply filter circuit is connected to the power supply ends of the voltage conversion circuit, the pulse signal conversion circuit, and the fault signal conversion circuit respectively. The voltage conversion circuit is connected to the low voltage power supply end of the pulse signal conversion circuit after reducing the voltage. The pulse signal conversion circuit inverts and shapes the optical pulse signal sent by the controller and sends it to the IGBT drive circuit. The fault signal conversion circuit converts the fault electrical signal sent by the IGBT drive circuit into an optical signal and sends it to the regulator.

[0006] The power supply filter circuit comprises a capacitor C3, the capacitor C3 is connected to the power supply, and a capacitor C5 is connected in parallel to the capacitor C3.

[0007] The capacitor C5 is connected in parallel with a power indication circuit, which includes a resistor R8 and a light emitting diode V2. The resistor R8 and the light emitting diode V2 are connected in series.

[0008] The voltage conversion circuit includes resistors R6, R7 and a voltage regulator tube V1. One end of the resistor R6 is connected to the power supply, and the other end of the resistor R6 is connected in series with R7 and the voltage regulator tube V1 in sequence. The voltage regulator tube V1 is connected in parallel with a capacitor C6, and the capacitor C6 is connected in parallel with a capacitor C4.

[0009] The pulse signal conversion circuit includes a first receiving sub-circuit and a Schmitt trigger U4 with an inverter. The first receiving sub-circuit is connected to the Schmitt trigger U4 with an inverter, the power supply end of the first receiving sub-circuit is connected to the power supply filter circuit, the low-voltage power supply end of the first receiving sub-circuit is connected to the voltage conversion circuit, the power supply end of the Schmitt trigger U4 with an inverter is connected to the power supply filter circuit, the power supply end of the Schmitt trigger U4 with an inverter is connected to the power supply filter circuit, a decoupling capacitor C10 is connected to the power supply end of the Schmitt trigger U4 with an inverter, and the Schmitt trigger U4 with an inverter is connected to the driving circuit of the IGBT.

[0010] The first receiving sub-circuit includes an optical fiber receiver U2, a capacitor C1 and a resistor R4. The capacitor C1 is connected to the optical fiber receiver U2, and the capacitor C1 is connected to the voltage conversion circuit. The optical fiber receiver U2 is connected to the power supply filter circuit through the resistor R4, and the optical fiber receiver U2 is connected to the Schmitt trigger U4 with an inverter.

[0011] The first receiving subcircuit is also connected to a first pulse indicating circuit, which includes a transistor Q1, a light-emitting diode V3 and a resistor R11. The base of the transistor Q1 is connected to the first receiving subcircuit, the collector of the transistor Q1 is connected to the power supply filter circuit through the resistor R11, and the emitter of the transistor Q1 is connected to the light-emitting diode V3.

[0012] The pulse signal conversion circuit also includes a second receiving sub-circuit, which includes an optical fiber receiver U3, a capacitor C2 and a resistor R5. The capacitor C2 is connected to the optical fiber receiver U3, and the capacitor C2 is connected to the voltage conversion circuit. The optical fiber receiver U3 is connected to the power supply filter circuit through the resistor R5, and the optical fiber receiver U3 is connected to the Schmitt trigger U4 with an inverter.

[0013] The second receiving sub-circuit is also connected to a second pulse indicating circuit, which includes a transistor Q2, a light-emitting diode V4 and a resistor R12. The base of the transistor Q2 is connected to the first receiving sub-circuit, the collector of the transistor Q2 is connected to the power supply filter circuit through the resistor R12, and the emitter of the transistor Q2 is connected to the light-emitting diode V4.

[0014] The fault signal conversion circuit includes a resistor R1 and an optical fiber receiver U1. The optical fiber receiver U1 is connected to the power supply filter circuit through the resistor R1. The optical fiber receiver U1 converts the fault electrical signal sent by the IGBT drive circuit into an optical signal and sends it to the regulator.

[0015] The beneficial effects of the present invention are as follows: the present invention filters the connected power supply through the power supply filter circuit and then connects to the voltage conversion circuit, the pulse signal conversion circuit and the fault signal conversion circuit respectively. Since the pulse signal conversion circuit requires the input of a low-voltage power supply, the power supply voltage is converted into a low-voltage power supply through the voltage conversion circuit and connected to the pulse signal conversion circuit. When the drive signal is transmitted, the pulse signal conversion circuit inverts and shapes the optical pulse signal emitted by the controller and sends it to the IGBT drive circuit to realize the photoelectric transmission of the drive signal. When the IGBT drive circuit fails, the fault signal conversion circuit converts the fault electrical signal sent by the IGBT drive circuit into an optical signal and sends it to the regulator. Therefore, the present invention realizes the optical fiber signal transmission between the control system and the drive circuit, effectively solves the isolation problem between the main circuit and the control circuit, greatly reduces the influence of electromagnetic interference, and realizes the long-distance transmission of the pulse signal. Among them, the power supply filtering circuit includes capacitors C3 and C5. After the power supply is filtered by capacitors C3 and C5, it is sent to other circuits. In order to display whether the power supply is normal in real time, a power supply indication circuit is connected in parallel to capacitor C5. The voltage conversion circuit includes resistors R6, R7 and a voltage regulator tube V1. The resistors R6, R7 and the voltage regulator tube V1 are used to convert the power supply voltage into the low voltage required by the pulse signal conversion circuit, and capacitors C4 and C6 can play a filtering role. The pulse signal conversion circuit includes a first receiving subcircuit and a Schmitt trigger U4 with an inverter. After the first receiving subcircuit obtains the inverted electrical pulse signal, it is sent to the Schmitt trigger U4 with an inverter. After U 4, the obtained pulse signal is sent to the driving circuit. In order to display in real time whether the pulse is output normally, the first receiving sub-circuit is also connected with a first pulse indicating circuit. In order to improve working efficiency, the pulse signal conversion circuit also includes a second receiving sub-circuit, so that the two receiving sub-circuits can work together. In order to display in real time whether the pulse is output normally, the second receiving sub-circuit is also connected with a second pulse indicating circuit. The fault signal conversion circuit includes a resistor R1 and an optical fiber receiver U1. When the IGBT fails, the fault electrical signal sent by the driving circuit is converted into an optical signal by the conversion circuit composed of the resistor R1 and the optical fiber receiver U1 and sent to the regulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the power supply filter circuit of the present invention;

[0017] Figure 2 is a schematic diagram of a voltage conversion circuit of the present invention;

[0018] Figure 3 It is a schematic diagram of a pulse signal conversion circuit of the present invention;

[0019] Figure 4It is a schematic diagram of the fault signal conversion circuit of the present invention. DETAILED DESCRIPTION

[0020] like Figure 1-Figure 4As shown, a photoelectric conversion device for IGBT drive signal transmission includes a power supply filter circuit, a voltage conversion circuit, a pulse signal conversion circuit, and a fault signal conversion circuit. The power supply filter circuit is connected to the power supply ends of the voltage conversion circuit, the pulse signal conversion circuit, and the fault signal conversion circuit respectively. The voltage conversion circuit reduces the voltage and is connected to the low voltage power supply end of the pulse signal conversion circuit. The pulse signal conversion circuit inverts and shapes the optical pulse signal sent by the controller and sends it to the IGBT drive circuit. The fault signal conversion circuit converts the fault electrical signal sent by the IGBT drive circuit into an optical signal and sends it to the regulator. The power supply filter circuit includes a capacitor C3, which is connected to the power supply. C3 is connected in parallel with a capacitor C5, and a power indication circuit is connected in parallel with the capacitor C5, the power indication circuit includes a resistor R8 and a light emitting diode V2, the resistor R8 is connected in series with the light emitting diode V2, the voltage conversion circuit includes resistors R6, R7 and a voltage regulator V1, one end of the resistor R6 is connected to the power supply, and the other end of the resistor R6 is connected in series with R7 and the voltage regulator V1 in sequence, a capacitor C6 is connected in parallel with the voltage regulator V1, and a capacitor C4 is connected in parallel with the capacitor C6, and a pulse signal conversion circuit includes a first receiving sub-circuit and a Schmitt trigger U4 with an inverter, the first receiving sub-circuit is connected to the Schmitt trigger U4 with an inverter, the power supply end of the first receiving sub-circuit is connected to the power supply filter circuit, and the first receiving sub-circuit The low voltage power supply end is connected to the voltage conversion circuit, the power supply end of the Schmitt trigger U4 with an inverter is connected to the power supply filter circuit, the power supply end of the Schmitt trigger U4 with an inverter is connected to a decoupling capacitor C10, the Schmitt trigger U4 with an inverter is connected to the IGBT drive circuit, the first receiving sub-circuit includes an optical fiber receiver U2, a capacitor C1 and a resistor R4, the capacitor C1 is connected to the optical fiber receiver U2, the capacitor C1 is connected to the voltage conversion circuit, the optical fiber receiver U2 is connected to the power supply filter circuit through the resistor R4, the optical fiber receiver U2 is connected to the Schmitt trigger U4 with an inverter, and the first receiving sub-circuit is also connected to a first pulse indication circuit, The first pulse indication circuit includes a transistor Q1, a light emitting diode V3 and a resistor R11, the base of the transistor Q1 is connected to the first receiving sub-circuit, the collector of the transistor Q1 is connected to the power supply filter circuit through the resistor R11, and the emitter of the transistor Q1 is connected to the light emitting diode V3. The pulse signal conversion circuit also includes a second receiving sub-circuit, the second receiving sub-circuit includes an optical fiber receiver U3, a capacitor C2 and a resistor R5, the optical fiber receiver U3 is connected to the capacitor C2, the capacitor C2 is connected to the voltage conversion circuit, the optical fiber receiver U3 is connected to the power supply filter circuit through the resistor R5, and the optical fiber receiver U3 is connected to the Schmitt trigger U4 with an inverter.The second receiving subcircuit is also connected to a second pulse indicating circuit, which includes a transistor Q2, a light emitting diode V4 and a resistor R12. The base of the transistor Q2 is connected to the first receiving subcircuit, the collector of the transistor Q2 is connected to the power filter circuit through the resistor R12, and the emitter of the transistor Q2 is connected to the light emitting diode V4. The fault signal conversion circuit includes a resistor R1 and an optical fiber receiver U1. The optical fiber receiver U1 is connected to the power filter circuit through the resistor R1. The optical fiber receiver U1 converts the fault electrical signal sent by the IGBT driving circuit into an optical signal and sends it to the regulator.

[0021] When the present invention is in use, a 15V power supply is used for power supply. After the 15V power supply is filtered by capacitors C3 and C5, it is sent to other circuits. The power supply indication circuit composed of resistor R8 and light-emitting diode V2 can display in real time whether the power supply is normal. The voltage conversion circuit uses resistors R6, R7 and voltage regulator tube V1 to convert the 15V voltage into the 5V voltage required by the pulse signal conversion circuit. C4 and C6 play a filtering role. In the pulse signal conversion circuit, the optical pulse signal emitted by the controller passes through the receiving circuit composed of optical fiber receiver U2, capacitor C1 and resistor R4 to obtain an inverted electrical pulse signal, which is then sent to the Schmidt contact with inverter. The transmitter U4, after being inverted and shaped by U4, sends the obtained pulse signal to the driving circuit, and the pulse indication circuit composed of the transistor Q1, the light-emitting diode V3, and the resistor R11 can display in real time whether the pulse is output normally. The optical fiber receiver U3, the capacitor C2, and the resistor R5 form the second receiving sub-circuit. The transistor Q2, the light-emitting diode V4, and the resistor R12 form the indication circuit of this pulse. The principle is the same as the first circuit. In the fault signal conversion circuit, when the IGBT fails, the fault electrical signal sent by the driving circuit is converted into an optical signal by the conversion circuit composed of the resistor R1 and the optical fiber receiver U1 and sent to the regulator.

[0022] The above are only embodiments of the present invention, and do not limit the patent protection scope of the present invention. In addition to the above embodiments, the present invention may also have other implementations, and any technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A photoelectric conversion device for IGBT drive signal transmission, characterized in that: The invention comprises a power supply filter circuit, a voltage conversion circuit, a pulse signal conversion circuit and a fault signal conversion circuit. The power supply filter circuit is respectively connected to the power supply ends of the voltage conversion circuit, the pulse signal conversion circuit and the fault signal conversion circuit. The voltage conversion circuit reduces the voltage and is connected to the low voltage power supply end of the pulse signal conversion circuit. The pulse signal conversion circuit inverts and shapes the optical pulse signal sent by the controller and sends it to the IGBT driving circuit. The fault signal conversion circuit converts the fault electrical signal sent by the IGBT driving circuit into an optical signal and sends it to the regulator. The pulse signal conversion circuit comprises a first receiving subcircuit and a Schmitt trigger U4 with an inverter. The first A receiving subcircuit is connected to a Schmitt trigger U4 with an inverter, a power supply end of the first receiving subcircuit is connected to the power supply filter circuit, a low-voltage power supply end of the first receiving subcircuit is connected to the voltage conversion circuit, a power supply end of the Schmitt trigger U4 with an inverter is connected to the power supply filter circuit, a decoupling capacitor C10 is connected to the power supply end of the Schmitt trigger U4 with an inverter, and the Schmitt trigger U4 with an inverter is connected to the driving circuit of the IGBT; the first receiving subcircuit includes an optical fiber receiver U2, a capacitor C1 and a resistor R4, a capacitor C1 is connected to the optical fiber receiver U2, and the capacitor C1 is connected to the voltage conversion circuit , the optical fiber receiver U2 is connected to the power supply filter circuit through the resistor R4, and the optical fiber receiver U2 is connected to the Schmitt trigger U4 with an inverter; the first receiving sub-circuit is also connected to a first pulse indication circuit, the first pulse indication circuit includes a transistor Q1, a light emitting diode V3 and a resistor R11, the base of the transistor Q1 is connected to the first receiving sub-circuit, the collector of the transistor Q1 is connected to the power supply filter circuit through the resistor R11, and the emitter of the transistor Q1 is connected to the light emitting diode V3; the pulse signal conversion circuit also includes a second receiving sub-circuit, the second receiving sub-circuit includes an optical fiber receiver U3, a capacitor C2 and resistor R5, the capacitor C2 on the optical fiber receiver U3 is connected, the capacitor C2 is connected to the voltage conversion circuit, the optical fiber receiver U3 is connected to the power supply filter circuit through the resistor R5, and the optical fiber receiver U3 is connected to the Schmitt trigger U4 with an inverter; the second receiving sub-circuit is also connected to a second pulse indication circuit, the second pulse indication circuit includes a transistor Q2, a light emitting diode V4 and a resistor R12, the base of the transistor Q2 is connected to the first receiving sub-circuit, the collector of the transistor Q2 is connected to the power supply filter circuit through the resistor R12, and the emitter of the transistor Q2 is connected to the light emitting diode V4;The fault signal conversion circuit includes a resistor R1 and an optical fiber receiver U1. The optical fiber receiver U1 is connected to the power filter circuit through the resistor R1. The optical fiber receiver U1 converts the fault electrical signal sent by the IGBT drive circuit into an optical signal and sends it to the regulator.

2. The photoelectric conversion device for IGBT drive signal transmission according to claim 1, characterized in that: The power supply filter circuit comprises a capacitor C3, the capacitor C3 is connected to the power supply, and a capacitor C5 is connected in parallel to the capacitor C3.

3. The photoelectric conversion device for IGBT drive signal transmission according to claim 2, characterized in that: The capacitor C5 is connected in parallel with a power indication circuit, which includes a resistor R8 and a light emitting diode V2. The resistor R8 and the light emitting diode V2 are connected in series.

4. The photoelectric conversion device for IGBT drive signal transmission according to claim 1, characterized in that: The voltage conversion circuit includes resistors R6, R7 and a voltage regulator tube V1. One end of the resistor R6 is connected to a power supply, and the other end of the resistor R6 is connected in series with R7 and the voltage regulator tube V1 in sequence. A capacitor C6 is connected in parallel to the voltage regulator tube V1, and a capacitor C4 is connected in parallel to the capacitor C6.

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