Comparator-based IGBT (Insulated Gate Bipolar Translator) driver power supply

Abstract

The invention discloses a PWM power supply circuit based on a comparator. The PWM power supply circuit comprises an input protection circuit, a PWM generation circuit, a DC / AC conversion circuit and an output circuit, the input protection circuit is used for performing input filtering, overcurrent and overvoltage protection and reverse connection protection on the input DC24V power supply; the PWM generation circuit is used for generating a PWM control signal with adjustable frequency, duty ratio, voltage and current, and sending the PWM control signal to the DC / AC conversion circuit; the DC / AC conversion circuit is used for performing power amplification on the PWM control signal to realize half-bridge inversion DC / AC; and the output circuit is used for carrying out AC / DC conversion and realizing stable voltage output. The comparator is used for generating a PWM control signal, the stability of the system is improved, the hysteresis control voltage threshold value is improved to 16V / 8V, and the anti-interference characteristic of the system is effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of control of electronic and automation equipment, and in particular relates to an IGBT driver power supply based on a comparator. Background Art

[0002] At present, IGBT is widely used in rail transit subway trains, mainly in inverters, DC / DC, chargers and other modules, as power switching devices in DC / AC conversion. In addition, IGBT as a switching device can also be used as a pre-charging module in the auxiliary inverter system to replace the pre-charging contactor.

[0003] Since the pre-charging module in the auxiliary inverter system is located on the positive input line of the inverter and is directly connected to the external high-voltage power supply, the working electromagnetic environment is harsh. The previous adjustable pulse width module solution cannot adapt to the harsh working environment of high electromagnetic interference of the pre-charging module; therefore, it is necessary to utilize the high gain and fast response characteristics of the voltage comparator to design a power supply to improve the reliability of the power supply. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide an IGBT driver power supply based on a comparator to solve the problem of the IGBT driver power supply in the pre-charging module resisting strong electromagnetic interference.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A comparator-based IGBT driver power supply of the present invention comprises: an input protection circuit, a PWM generation circuit, a DC / AC conversion circuit and an output circuit;

[0007] Input protection circuit, used for input filtering, over-current and over-voltage protection, and reverse connection protection of the input DC24V power supply;

[0008] PWM generating circuit, used to generate PWM control signal with adjustable frequency, duty cycle, voltage and current, and send the PWM control signal to DC / AC conversion circuit;

[0009] DC / AC conversion circuit, used to amplify the power of PWM control signal to realize half-bridge inverter DC / AC;

[0010] The output circuit is used to perform AC / DC conversion and achieve stable voltage output.

[0011] Furthermore, the input protection circuit includes: a common mode filter circuit, a differential mode filter circuit and an overvoltage protection circuit;

[0012] The common mode filter circuit includes: capacitor C18 and capacitor C19; pin 2 of capacitor C18 is connected to an external DC24V power supply, pin 1 of capacitor C18 is connected to pin 2 of capacitor C19 and external protection ground PGND, and pin 1 of capacitor C19 is connected to an external 0V power supply and GND;

[0013] The differential mode filter circuit includes: a resistor R11 and a capacitor C13; a pin 2 of the resistor R11 is connected to an external input power supply +24V, a pin 1 of the resistor R11 is connected to a pin 1 of the capacitor C13, and a pin 2 of the capacitor C13 is connected to GND;

[0014] The overvoltage protection circuit is composed of a TVS tube D1. Pin 2 of the TVS tube D1 is connected to pin 1 of the resistor R11 and VC1_24V respectively, and pin 1 of the TVS tube D1 is connected to GND.

[0015] Furthermore, the PWM generation circuit includes: an RC filter circuit, a duty cycle adjustment circuit, a hysteresis threshold adjustment circuit and an output waveform adjustment circuit;

[0016] The RC filter circuit includes: a resistor R12 and a capacitor C11; pin 2 of the resistor R12 is connected to VC1_24V, pin 1 of the resistor R12 is connected to pin 2 of the capacitor C11, and pin 1 of the capacitor C11 is connected to GND;

[0017] The duty cycle adjustment circuit includes: a comparator U11C, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a capacitor C12 and a diode D12; Pin 2 of the resistor R13 is connected to Pin 2 of the capacitor C11, Pin 1 of the resistor R13 is respectively connected to Pin 2 of the resistor R14 and Pin 9 of the comparator U11C, and Pin 1 of the resistor R14 is connected to GND; Pin 1 of the resistor R17 is connected to Pin 2 of the capacitor C11, Pin 2 of the resistor R17 is connected to Pin 14 of the comparator U11C, Pin 1 of the resistor R16 is respectively connected to Pin 3 of the diode D12 and Pin 2 of the resistor R17, and Pin 2 of the resistor R16 is respectively connected to Pin 1 of the diode D12 and Pin 2 of the resistor R15; Pin 1 of the resistor R15 is connected to Pin 1 of the capacitor C12 and Pin 8 of the comparator U11C, and Pin 2 of the capacitor C12 is connected to GND;

[0018] The hysteresis threshold adjustment circuit includes: a comparator U11B, a resistor R19, a resistor R110, a resistor R18, a resistor R1, a resistor R112, a capacitor C14 and a diode D13; the pin 1 of the resistor R1 is connected to the pin 2 of the capacitor C11, the pin 2 of the resistor R1 is connected to the pin 2 of the comparator U11B, the pin 3 of the diode D13, and the pin 2 of the resistor R112; the pins 1 and 2 of the diode D13 are connected to the pin 1 of the resistor R112, the comparator U11B ... Pin 9 of the comparator U11C is connected; Pin 2 of the resistor R18 is connected to Pin 2 of the resistor R17, and Pin 1 of the resistor R18 is connected to Pin 5 of the comparator U11B; Pin 2 of the resistor R19 is connected to Pin 2 of the capacitor C11, and Pin 1 of the resistor R19 is connected to Pin 4 of the comparator U11B; Pin 2 of the resistor R110 is connected to Pin 2 of the capacitor C14 and Pin 1 of the resistor R19 respectively, and Pin 1 of the resistor R110 and Pin 1 of the capacitor C14 are connected to GND;

[0019] The output waveform adjustment circuit includes: a comparator U11A, a resistor R114, a resistor R113, a resistor R115 and a capacitor C15; pin 1 of the resistor R114 is connected to pin 2 of the capacitor C11, pin 2 of the resistor R114 is connected to pin 2 of the capacitor R115, pin 1 of the resistor R115 is connected to GND, capacitor C15 is connected in parallel with the resistor R115, pin 2 of the capacitor C15 is respectively connected to pin 2 of the resistor R115 and pin 7 of the comparator U11A, and pin 1 of the capacitor C15 is connected to GND; pin 1 of the resistor R113 is connected to pin 2 of the resistor R1, and pin 2 of the resistor R113 is connected to pin 6 of the comparator U11A.

[0020] Furthermore, the DC / AC conversion circuit includes: a voltage stabilizing filter circuit, a power amplifier circuit, and a field effect transistor drive circuit;

[0021] The voltage stabilizing filter circuit includes: a voltage stabilizing tube D4, a resistor R116, a resistor R117 and a capacitor C17; the pin 2 of the voltage stabilizing tube D4 is connected to VC1_24V, the pin 1 of the voltage stabilizing tube D4 is connected to the pin 1 of the resistor R116, and the pin 2 of the resistor R116 is connected to GND; the pin 2 of the resistor R117 is connected to the pin 1 of the resistor R116, the pin 1 of the resistor R117 is connected to the pin 1 of the capacitor C17, and the pin 2 of the capacitor C17 is connected to GND;

[0022] The power amplifier circuit includes: resistor R118, resistor R119, resistor R120, resistor R121, transistor Q11, transistor Q12, transistor Q13, transistor Q14, voltage regulator D15 and voltage regulator D16; pin 2 of resistor R118 is connected to pin 1 of capacitor C17, pin 1 of resistor R118 is connected to pin 1 of comparator U11A, pin 1 of resistor R119 is connected to pin 1 of comparator U11A, pin 2 of resistor R119 is respectively connected to pin 1 of transistor Q11 and pin 1 of transistor Q12; pin 2 of transistor Q11 is connected to pin 2 of transistor Q12, pin 3 of transistor Q11 is connected to pin 1 of resistor R120, pin 2 of resistor R120 is connected to pin 1 of transistor Q11 and pin 1 of transistor Q12. Connected to pin 1 of capacitor C17; pin 3 of transistor Q12 is connected to pin 2 of resistor R121, and pin 1 of resistor R121 is connected to GND; pin 1 of transistor Q13 is connected to pin 1 of resistor R120, pin 3 of transistor Q13 is connected to pin 1 of capacitor C17, and pin 2 of transistor Q13 is respectively connected to pin 2 of transistor Q14 and pin 2 of transistor Q11; pin 1 of transistor Q14 is connected to pin 2 of resistor R121, and pin 3 of transistor Q14 is connected to GND; pin 2 of voltage regulator D15 is connected to pin 1 of capacitor C17, and pin 1 of voltage regulator D15 is respectively connected to pin 2 of voltage regulator D16 and pin 2 of transistor Q13; pin 1 of voltage regulator D16 is connected to GND;

[0023] The field effect transistor driving circuit includes: capacitor C8, capacitor C29, capacitor C210, resistor R222, resistor R223, resistor R224, resistor R225, resistor R226, transformer L21, diode D27, diode D28, voltage regulator D29, voltage regulator D210, voltage regulator D211, voltage regulator D212, transistor Q25 and transistor Q26; pin 2 of capacitor C8 is connected to pin 1 of capacitor C17, and pin 1 of capacitor C8 is connected to pin 6 of transformer L21. Connect, the 10th pin of transformer L21 is connected to the 1st pin of resistor R222, the 2nd pin of resistor R222 is connected to the 2nd pin of voltage regulator tube D16; the 2nd pin of resistor R223 is connected to the 2nd pin of transformer L21, the 1st pin of resistor R223 is connected to the 1st pin of transformer L21; the 1st pin of resistor R224 is connected to the 4th pin of transformer L21, the 2nd pin of resistor R224 is connected to the 5th pin of transformer L21 and GND respectively; the 1st pin of resistor R223 is connected to the 2nd pin of R225 respectively, the diode D The 1st and 2nd pins of the resistor R224 are connected to the 2nd pin of the resistor R226, the 1st pin of the diode D28 and the 2nd pin of the diode D28, the 1st pin of the resistor R226 is connected to the 3rd pin of the diode D28, the 1st pin of the voltage regulator D210 and the 3rd pin of the transistor Q25, respectively; the 2nd pin of the resistor R223 is also connected to the 1st pin of the voltage regulator D210 and the 3rd pin of the transistor Q25, respectively; the 1st pin of the resistor R224 is connected to the 2nd pin of the resistor R226, the 1st pin of the diode D28 and the 2nd pin of the diode D28, the 1st pin of the resistor R226 is connected to the 3rd pin of the diode D28 and the 1st pin of the voltage regulator D211, respectively. Pin 2 of the voltage regulator D211 is connected to pin 2 of the voltage regulator D212, and pin 1 of the voltage regulator D212 is connected to GND; pin 2 of the transistor Q25 is connected to VC1_24V, pin 3 of the transistor Q25 is connected to pin 2 of the transistor Q26, and pin 3 of the transistor Q26 is connected to GND; pin 2 of the capacitor C29 is connected to VC1_24V, pin 1 of the capacitor C29 is connected to pin 1 of the capacitor C210, and pin 2 of the capacitor C210 is connected to GND.

[0024] Further, the output circuit includes: an isolation transformer T31, a diode DA3, a diode DA4, a diode DA5, a diode DA6, a diode DA7, a diode DA8, a diode DB1, a diode DB2, a diode D9, a diode D10, a voltage regulator D7, a voltage regulator D8, a resistor R31, a resistor R32, a resistor RA36, a capacitor C33, a capacitor C31, a capacitor C13, a capacitor C12, a capacitor C16, a capacitor C348, a capacitor C15, a capacitor C32, a capacitor C336, a three-terminal voltage regulator U31 and a three-terminal voltage regulator U32;

[0025] Pin 5 of the isolation transformer T31 is connected to pin 2 of the resistor R223, pin 3 of the isolation transformer T31 is connected to pin 1 of the capacitor C29, pin 8 of the isolation transformer T31 is connected to pin 1 of the diode DA4 and pin 2 of the diode DA3, pin 9 of the isolation transformer T31 is connected to pin 1 of the diode DA5 and pin 2 of the diode DA6, pin 7 of the isolation transformer T31 is connected to pin 1 of the diode DB2 and pin 2 of the diode DB1, pin 1 of the isolation transformer T31 is connected to pin 1 of the diode DA7 and pin 2 of the diode DA8, pin 2 and pin 6 of the isolation transformer T31 are connected to GND2; pin 2 of the diode DA4 is connected to pin 1 of the diode DA7 and pin 2 of the diode DA8, pin 2 and pin 6 of the isolation transformer T31 are connected to GND2; pin 2 of the diode DA4 is connected to pin 1 of the diode DA5 and pin 2 of the diode DA6, respectively. Connected to pin 2 of diode DA5 and pin 1 of resistor R32, pin 1 of diode DA3 is respectively connected to pin 1 of diode DA6 and pin 2 of diode DB2; pin 2 of diode DB2 is also connected to pin 2 of diode DA7; pin 1 of diode DB1 is connected to pin 1 of diode DA8; pin 1 of resistor R31 is respectively connected to pin 1 of resistor R32 and pin 2 of diode DA5, pin 2 of resistor R31 is respectively connected to pin 2 of resistor R32, pin 1 of resistor RA36, pin 2 of capacitor C16, and pin 1 of capacitor C33 +36V power supply; pin 2 of resistor RA36, pin 1 of capacitor C16, and pin 2 of capacitor C33 are all connected to GND2;

[0026] After the pin 1 of capacitor C13, the pin 1 of capacitor C31 and the pin 1 of three-terminal voltage regulator U31 are connected, they are connected to the pin 2 of diode DB2; the pin 2 of capacitor C13 and the pin 2 of capacitor C31 are both connected to GND2; the pin 2 of three-terminal voltage regulator U31 is connected to the pin 1 of diode D9, the pin 2 of diode D9 is connected to the pin 1 of diode D10, and the pin 2 of diode D10 is connected to GND2; the pin 3 of three-terminal voltage regulator U31 is respectively connected to the pin 2 of capacitor C12, the pin 1 of capacitor C348 and the +15V power supply; the pin 1 of capacitor C12 and the pin 2 of capacitor C348 are both connected to GND2; Pin 1 of capacitor C15, pin 2 of capacitor C32, pin 1 of diode DB1, and pin 2 of three-terminal voltage regulator U32 are connected, and pin 2 of capacitor C15 and pin 1 of capacitor C32 are connected to GND2; pin 2, pin 3, pin 6, and pin 7 of the three-terminal voltage regulator U32 are connected together; pin 5 of the three-terminal voltage regulator U32 is connected to pin 2 of the voltage regulator D8, pin 1 of the voltage regulator D8 is connected to pin 2 of the voltage regulator D7, and pin 1 of the voltage regulator D7 is connected to GND2; pin 1 of the three-terminal voltage regulator U32 is respectively connected to the -15V power supply and pin 2 of capacitor C336, and pin 1 of capacitor C336 is connected to GND2.

[0027] Furthermore, the IGBT driver power supply is powered by a 24V-0V DC power supply, the input current limit is 2A, and the input voltage limit is 28V.

[0028] Furthermore, the PWM generating circuit is powered by an internal VC1_24V power supply, which is powered by a secondary RC low-pass filter, and the hysteresis threshold is set to 16V and 8V, the PWM duty cycle is 50%, and the period is 10us.

[0029] Furthermore, the DC / AC conversion circuit is powered by an internal VC1_24V power supply, which, after voltage stabilization, supplies power to the DC / AC conversion circuit, further ensuring the voltage stability and anti-interference capability of the DC / AC control circuit.

[0030] Furthermore, the output current of the output circuit is 500mA and the total output power is 15W.

[0031] The PWM signal in the present invention is generated by a voltage comparator, and a higher voltage hysteresis threshold is set to improve the anti-interference characteristics of the PWM signal. A DC24V power supply is used, so the threshold voltage is set to 16V / 8V. The frequency, duty cycle, voltage, current and other parameters of the PWM signal are adjusted according to specific needs, and it has protection functions such as power reverse, input overvoltage, and output overcurrent.

[0032] Beneficial effects of the present invention:

[0033] In the present invention, a comparator is used to generate a PWM control signal, which improves the stability of the system, increases the hysteresis control voltage threshold to 16V / 8V, and effectively improves the anti-interference characteristic of the system.

[0034] The present invention meets the power supply requirement of the IGBT driver in the current pre-charging module and further expands the application scope of the IGBT. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a principle block diagram of the power supply of the present invention.

[0036] Figure 2 This is the input protection circuit schematic diagram of the present invention.

[0037] Figure 3 This is a schematic diagram of the PWM generating circuit in the present invention.

[0038] Figure 4 This is a schematic diagram of the DC / AC conversion circuit in the present invention.

[0039] Figure 5 This is the schematic diagram of the output circuit in the present invention. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0041] Reference Figures 1 to 5 As shown, a comparator-based IGBT driver power supply of the present invention includes: an input protection circuit, a PWM generation circuit, a DC / AC conversion circuit and an output circuit;

[0042] Input protection circuit, used for input filtering, over-current and over-voltage protection, and reverse connection protection of the input DC24V power supply;

[0043] PWM generating circuit, used to generate PWM control signal with adjustable frequency, duty cycle, voltage and current, and send the PWM control signal to DC / AC conversion circuit;

[0044] DC / AC conversion circuit, used to amplify the power of PWM control signal to realize half-bridge inverter DC / AC;

[0045] The output circuit is used to perform AC / DC conversion and achieve stable voltage output.

[0046] Specifically, the input protection circuit includes: a common mode filter circuit, a differential mode filter circuit and an overvoltage protection circuit;

[0047] The common mode filter circuit includes: capacitor C18 and capacitor C19; pin 2 of capacitor C18 is connected to the external DC24V power supply, pin 1 of capacitor C18 is connected to pin 2 of capacitor C19 and external protection ground PGND respectively, and pin 1 of capacitor C19 is connected to the external 0V power supply and GND respectively; the common mode filter circuit is used to filter out high frequency common mode interference in the 24V power supply;

[0048] The differential mode filter circuit includes: a resistor R11 and a capacitor C13; the 2nd pin of the resistor R11 is connected to the external input power supply +24V, the 1st pin of the resistor R11 is connected to the 1st pin of the capacitor C13, and the 2nd pin of the capacitor C13 is connected to GND; the differential mode filter circuit is used to filter out the high-frequency differential mode interference in the power supply, so that the internal 24V voltage is more stable;

[0049] The overvoltage protection circuit is composed of TVS tube D1. Pin 2 of TVS tube D1 is connected to pin 1 of resistor R11 and VC1_24V respectively, and pin 1 of TVS tube D1 is connected to GND. TVS tube D1 is used for overvoltage protection. It limits the voltage of VC1_24V to below 28V and can also prevent reverse connection. Its forward conduction characteristic is 100A / 3.5V, which causes R11 to fuse to protect subsequent circuits.

[0050] Specifically, the PWM generation circuit includes: an RC filter circuit, a duty cycle adjustment circuit, a hysteresis threshold adjustment circuit and an output waveform adjustment circuit;

[0051] The RC filter circuit includes: resistor R12 and capacitor C11; pin 2 of resistor R12 is connected to VC1_24V, pin 1 of resistor R12 is connected to pin 2 of capacitor C11, and pin 1 of capacitor C11 is connected to GND; it supplies power to the internal circuit of PWM, and after low-pass filtering, the voltage is more stable, and it can prevent the comparator from being damaged due to the potential of the input pin exceeding the voltage range of the chip power pin, which can improve the reliability of the power supply;

[0052] The duty cycle adjustment circuit includes: a comparator U11C, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a capacitor C12 and a diode D12; Pin 2 of the resistor R13 is connected to Pin 2 of the capacitor C11, Pin 1 of the resistor R13 is respectively connected to Pin 2 of the resistor R14 and Pin 9 of the comparator U11C, and Pin 1 of the resistor R14 is connected to GND; Pin 1 of the resistor R17 is connected to Pin 2 of the capacitor C11, Pin 2 of the resistor R17 is connected to Pin 14 of the comparator U11C, Pin 1 of the resistor R16 is respectively connected to Pin 3 of the diode D12 and Pin 2 of the resistor R17, and Pin 2 of the resistor R16 is respectively connected to Pin 1 of the diode D12 and Pin 2 of the resistor R15; Pin 1 of the resistor R15 is connected to Pin 1 of the capacitor C12 and Pin 8 of the comparator U11C, and Pin 2 of the capacitor C12 is connected to Pin 1 of the capacitor C12. The pin is connected to GND; when the 14th pin of the comparator U11C outputs a high level, the capacitor C12 is charged through the resistor R17, the diode D12 and the resistor R15, and the potential of the 8th pin of the comparator U11C continues to rise. When the potential of the 8th pin is higher than the potential of the 9th pin, the 14th pin of the comparator U11C reverses and outputs a low level; the capacitor C12 is discharged through the resistor R15 and the resistor R16, and the potential of the 8th pin of the comparator U11C continues to decrease. When it is lower than the potential of the 9th pin, the 14th pin of the comparator U11C reverses and outputs a high level again; this goes back and forth to output the PWM control signal; by adjusting the parameters of the resistor R15, the resistor R16, the resistor R17 and the capacitor C12, the high level time and the low level time of the 14th pin of the comparator U11C are adjusted to achieve the purpose of adjusting the PWM duty cycle and period, and the voltage hysteresis value of the 9th pin is set to 16 / 8V;

[0053] The hysteresis threshold adjustment circuit includes: a comparator U11B, a resistor R19, a resistor R110, a resistor R18, a resistor R1, a resistor R112, a capacitor C14 and a diode D13; a pin 1 of the resistor R1 is connected to a pin 2 of the capacitor C11, and a pin 2 of the resistor R1 is respectively connected to a pin 2 of the comparator U11B, a pin 3 of the diode D13, and a pin 2 of the resistor R112; pins 1 and 2 of the diode D13 are both connected to a pin 1 of the resistor R112 and a pin 9 of the comparator U11C; a pin 2 of the resistor R18 is connected to a pin 2 of the resistor R17, and a pin 1 of the resistor R18 is connected to a pin 5 of the comparator U11B; a pin 2 of the resistor R19 is connected to a pin 3 of the diode D13, and a pin 2 of the diode D13; a pin 1 of the resistor R19 is connected to a pin 2 of the resistor R17, and a pin 1 of the resistor R18 is connected to a pin 5 of the comparator U11B; a pin 2 ...9. Connected to pin 2 of capacitor C11, pin 1 of resistor R19 is connected to pin 4 of comparator U11B; pin 2 of resistor R110 is connected to pin 2 of capacitor C14 and pin 1 of resistor R19 respectively, and pin 1 of resistor R110 and pin 1 of capacitor C14 are connected to GND; the potential of pin 4 of comparator U11B is set to 12V, when pin 14 of comparator U11C outputs high level, pin 2 of comparator U11B outputs high level, and the potential of pin 9 of comparator U11C is 16V, when pin 14 of comparator U11C outputs low level, pin 2 of comparator U11B outputs low level, and the potential of pin 9 of comparator U11C is 8V;

[0054] The output waveform adjustment circuit includes: a comparator U11A, a resistor R114, a resistor R113, a resistor R115 and a capacitor C15; pin 1 of the resistor R114 is connected to pin 2 of the capacitor C11, pin 2 of the resistor R114 is connected to pin 2 of the capacitor R115, pin 1 of the resistor R115 is connected to GND, capacitor C15 is connected in parallel with resistor R115, pin 2 of the capacitor C15 is respectively connected to pin 2 of the resistor R115 and pin 7 of the comparator U11A, and pin 1 of the capacitor C15 is connected to GND; pin 1 of the resistor R113 is connected to pin 2 of the resistor R1, and pin 2 of the resistor R113 is connected to pin 6 of the comparator U11A; when pin 2 of the comparator U11B outputs a high level, pin 1 of the comparator U11A outputs a low level, and when pin 2 of the comparator U11B outputs a low level, pin 1 of the comparator U11A outputs a high level, thereby realizing the functions of PWM wave inversion and shaping;

[0055] Specifically, the DC / AC conversion circuit includes: a voltage stabilizing filter circuit, a power amplifier circuit, and a field effect transistor drive circuit;

[0056] The voltage stabilizing filter circuit includes: a voltage stabilizing tube D4, a resistor R116, a resistor R117 and a capacitor C17; the pin 2 of the voltage stabilizing tube D4 is connected to VC1_24V, the pin 1 of the voltage stabilizing tube D4 is connected to the pin 1 of the resistor R116, and the pin 2 of the resistor R116 is connected to GND; the pin 2 of the resistor R117 is connected to the pin 1 of the resistor R116, the pin 1 of the resistor R117 is connected to the pin 1 of the capacitor C17, and the pin 2 of the capacitor C17 is connected to GND; the resistor R117 and the capacitor C17 form an RC filter circuit, which supplies power to the internal circuit of the DC / AC, and after low-pass filtering, the voltage is more stable;

[0057] The power amplifier circuit includes: resistor R118, resistor R119, resistor R120, resistor R121, transistor Q11, transistor Q12, transistor Q13, transistor Q14, voltage regulator D15 and voltage regulator D16; pin 2 of resistor R118 is connected to pin 1 of capacitor C17, pin 1 of resistor R118 is connected to pin 1 of comparator U11A, pin 1 of resistor R119 is connected to pin 1 of comparator U11A, pin 2 of resistor R119 is respectively connected to pin 1 of transistor Q11 and pin 1 of transistor Q12; pin 2 of transistor Q11 is connected to pin 2 of transistor Q12, pin 3 of transistor Q11 is connected to pin 1 of resistor R120, pin 2 of resistor R120 is connected to pin 1 of transistor Q11 and pin 1 of transistor Q12. Connected to pin 1 of capacitor C17; pin 3 of transistor Q12 is connected to pin 2 of resistor R121, and pin 1 of resistor R121 is connected to GND; pin 1 of transistor Q13 is connected to pin 1 of resistor R120, pin 3 of transistor Q13 is connected to pin 1 of capacitor C17, and pin 2 of transistor Q13 is respectively connected to pin 2 of transistor Q14 and pin 2 of transistor Q11; pin 1 of transistor Q14 is connected to pin 2 of resistor R121, and pin 3 of transistor Q14 is connected to GND; pin 2 of voltage regulator D15 is connected to pin 1 of capacitor C17, and pin 1 of voltage regulator D15 is respectively connected to pin 2 of voltage regulator D16 and pin 2 of transistor Q13; pin 1 of voltage regulator D16 is connected to GND;

[0058] The field effect transistor driving circuit includes: capacitor C8, capacitor C29, capacitor C210, resistor R222, resistor R223, resistor R224, resistor R225, resistor R226, transformer L21, diode D27, diode D28, voltage regulator D29, voltage regulator D210, voltage regulator D211, voltage regulator D212, transistor Q25 and transistor Q26; pin 2 of capacitor C8 is connected to pin 1 of capacitor C17, and pin 1 of capacitor C8 is connected to pin 6 of transformer L21. Connect, the 10th pin of transformer L21 is connected to the 1st pin of resistor R222, the 2nd pin of resistor R222 is connected to the 2nd pin of voltage regulator tube D16; the 2nd pin of resistor R223 is connected to the 2nd pin of transformer L21, the 1st pin of resistor R223 is connected to the 1st pin of transformer L21; the 1st pin of resistor R224 is connected to the 4th pin of transformer L21, the 2nd pin of resistor R224 is connected to the 5th pin of transformer L21 and GND respectively; the 1st pin of resistor R223 is connected to the 2nd pin of R225 respectively, the diode D The 1st and 2nd pins of the resistor R224 are connected to the 2nd pin of the resistor R226, the 1st pin of the diode D28 and the 2nd pin of the diode D28, the 1st pin of the resistor R226 is connected to the 3rd pin of the diode D28, the 1st pin of the voltage regulator D210 and the 3rd pin of the transistor Q25, respectively; the 2nd pin of the resistor R223 is also connected to the 1st pin of the voltage regulator D210 and the 3rd pin of the transistor Q25, respectively; the 1st pin of the resistor R224 is connected to the 2nd pin of the resistor R226, the 1st pin of the diode D28 and the 2nd pin of the diode D28, the 1st pin of the resistor R226 is connected to the 3rd pin of the diode D28 and the 1st pin of the voltage regulator D211, respectively. Pin 2 of the voltage regulator D211 is connected to pin 2 of the voltage regulator D212, and pin 1 of the voltage regulator D212 is connected to GND; pin 2 of the transistor Q25 is connected to VC1_24V, pin 3 of the transistor Q25 is connected to pin 2 of the transistor Q26, and pin 3 of the transistor Q26 is connected to GND; pin 2 of the capacitor C29 is connected to VC1_24V, pin 1 of the capacitor C29 is connected to pin 1 of the capacitor C210, and pin 2 of the capacitor C210 is connected to GND;

[0059] Resistors R118 and R119 form a base control circuit of transistors Q11 and Q12. When PWM is at a high level, transistor Q11 is turned on and transistor Q12 is turned off. When PWM is at a low level, transistor Q11 is turned off and transistor Q12 is turned on. Transistor Q11 and resistor R120 form a first-stage upper bridge arm amplifier circuit. After transistor Q11 is turned on, transistor Q13 is controlled to be turned on. Similarly, transistor Q12 and resistor R121 control transistor Q14 to be turned on. Zener diodes D15 and D16 protect transistors Q13 and Q14 from overvoltage breakdown and play a role in freewheeling. The alternating switching on of transistors Q11 and Q12 generates alternating current in the primary coil of transformer L21 and induces alternating current in the secondary coil; the alternating switching on of field effect transistors Q25 and Q26 are controlled respectively to generate alternating current in the primary coil of the output transformer; capacitors C29, C210 and field effect transistors Q25 and Q26 form a half-bridge inverter circuit, which converts DC24V direct current into alternating current and inputs it into the primary coil of the output transformer; voltage regulators D29 and D210 protect the VGE voltage of transistor Q25 from not exceeding ±20V, and resistor R225 and diode D27 control the switching rate of transistor Q25. Voltage regulators D211 and D212 protect the VGE voltage of transistor Q26 from not exceeding ±20V, and resistor R226 and diode D28 control the switching rate of transistor Q26; resistors R223 and R224 are load resistors.

[0060] Specifically, the output circuit includes: an isolation transformer T31, a diode DA3, a diode DA4, a diode DA5, a diode DA6, a diode DA7, a diode DA8, a diode DB1, a diode DB2, a diode D9, a diode D10, a voltage regulator D7, a voltage regulator D8, a resistor R31, a resistor R32, a resistor RA36, a capacitor C33, a capacitor C31, a capacitor C13, a capacitor C12, a capacitor C16, a capacitor C348, a capacitor C15, a capacitor C32, a capacitor C336, a three-terminal voltage regulator U31 and a three-terminal voltage regulator U32;

[0061] Pin 5 of the isolation transformer T31 is connected to pin 2 of the resistor R223, pin 3 of the isolation transformer T31 is connected to pin 1 of the capacitor C29, pin 8 of the isolation transformer T31 is connected to pin 1 of the diode DA4 and pin 2 of the diode DA3, pin 9 of the isolation transformer T31 is connected to pin 1 of the diode DA5 and pin 2 of the diode DA6, pin 7 of the isolation transformer T31 is connected to pin 1 of the diode DB2 and pin 2 of the diode DB1, pin 1 of the isolation transformer T31 is connected to pin 1 of the diode DA7 and pin 2 of the diode DA8, pin 2 and pin 6 of the isolation transformer T31 are connected to GND2; pin 2 of the diode DA4 is connected to pin 1 of the diode DA7 and pin 2 of the diode DA8, pin 2 and pin 6 of the isolation transformer T31 are connected to GND2; pin 2 of the diode DA4 is connected to pin 1 of the diode DA5 and pin 2 of the diode DA6, respectively. Connected to pin 2 of diode DA5 and pin 1 of resistor R32, pin 1 of diode DA3 is respectively connected to pin 1 of diode DA6 and pin 2 of diode DB2; pin 2 of diode DB2 is also connected to pin 2 of diode DA7; pin 1 of diode DB1 is connected to pin 1 of diode DA8; pin 1 of resistor R31 is respectively connected to pin 1 of resistor R32 and pin 2 of diode DA5, pin 2 of resistor R31 is respectively connected to pin 2 of resistor R32, pin 1 of resistor RA36, pin 2 of capacitor C16, and pin 1 of capacitor C33 +36V power supply; pin 2 of resistor RA36, pin 1 of capacitor C16, and pin 2 of capacitor C33 are all connected to GND2;

[0062] After the pin 1 of capacitor C13, the pin 1 of capacitor C31 and the pin 1 of three-terminal voltage regulator U31 are connected, they are connected to the pin 2 of diode DB2; the pin 2 of capacitor C13 and the pin 2 of capacitor C31 are both connected to GND2; the pin 2 of three-terminal voltage regulator U31 is connected to the pin 1 of diode D9, the pin 2 of diode D9 is connected to the pin 1 of diode D10, and the pin 2 of diode D10 is connected to GND2; the pin 3 of three-terminal voltage regulator U31 is respectively connected to the pin 2 of capacitor C12, the pin 1 of capacitor C348 and the +15V power supply; the pin 1 of capacitor C12 and the pin 2 of capacitor C348 are both connected to GND2; Pin 1 of capacitor C15, pin 2 of capacitor C32, pin 1 of diode DB1, and pin 2 of three-terminal voltage regulator U32 are connected, and pin 2 of capacitor C15 and pin 1 of capacitor C32 are connected to GND2; pin 2, pin 3, pin 6, and pin 7 of three-terminal voltage regulator U32 are connected together; pin 5 of three-terminal voltage regulator U32 is connected to pin 2 of voltage regulator tube D8, pin 1 of voltage regulator tube D8 is connected to pin 2 of voltage regulator tube D7, and pin 1 of voltage regulator tube D7 is connected to GND2; pin 1 of three-terminal voltage regulator U32 is respectively connected to -15V power supply and pin 2 of capacitor C336, and pin 1 of capacitor C336 is connected to GND2;

[0063] Isolation transformer T31 isolates the DC24V power supply from the output circuit; diodes DA3~DA6 form a full-bridge rectifier circuit, which outputs a DC36V voltage after passing through an RC filter circuit composed of resistors R32, R31, RA36, C16, and C33; diodes DB2, DA7, DB1, and DA8 form a full-wave rectifier circuit, which outputs a positive and negative 20V voltage, capacitors C13, C31, C15, and C32 form a low-pass filter circuit, and three-terminal regulators U31 and U32 output ±15V voltage. Diodes D9 and D10 are used to protect the three-terminal regulator U31, and regulator tubes D7 and D8 are used to protect the three-terminal regulator U32; capacitors C12, C348, and C336 are output filter capacitors.

[0064] The IGBT driver power supply is powered by a 24V-0V DC power supply, the input current limit is 2A, and the input voltage limit is 28V.

[0065] The PWM generating circuit is powered by an internal VC1_24V power supply, which is powered by a secondary RC low-pass filter. The hysteresis threshold is set to 16V and 8V, the PWM duty cycle is 50%, and the period is 10us.

[0066] Among them, the DC / AC conversion circuit is powered by an internal VC1_24V power supply, which, after voltage stabilization, supplies power to the DC / AC conversion circuit, further ensuring the voltage stability and anti-interference ability of the DC / AC control circuit.

[0067] The output current of the output circuit is 500mA and the total output power is 15W.

[0068] The present invention has many specific application paths. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements can be made without departing from the principle of the present invention. These improvements should also be regarded as the protection scope of the present invention.

Claims

1. A comparator-based IGBT driver power supply, characterized in that: include: Input protection circuit, PWM generation circuit, DC / AC conversion circuit and output circuit; Input protection circuit, used for input filtering, over-current and over-voltage protection, and reverse connection protection of the input DC24V power supply; PWM generating circuit, used to generate PWM control signal with adjustable frequency, duty cycle, voltage and current, and send the PWM control signal to DC / AC conversion circuit; DC / AC conversion circuit, used to amplify the power of PWM control signal to realize half-bridge inverter DC / AC; The output circuit is used to perform AC / DC conversion and achieve stable voltage output.

2. The comparator-based IGBT driver power supply according to claim 1, characterized in that: The input protection circuit includes: a common mode filter circuit, a differential mode filter circuit and an overvoltage protection circuit; The common mode filter circuit includes: capacitor C18 and capacitor C19; pin 2 of capacitor C18 is connected to an external DC24V power supply, pin 1 of capacitor C18 is connected to pin 2 of capacitor C19 and external protection ground PGND, and pin 1 of capacitor C19 is connected to an external 0V power supply and GND; The differential mode filter circuit includes: a resistor R11 and a capacitor C13; a pin 2 of the resistor R11 is connected to an external input power supply +24V, a pin 1 of the resistor R11 is connected to a pin 1 of the capacitor C13, and a pin 2 of the capacitor C13 is connected to GND; The overvoltage protection circuit is composed of a TVS tube D1. Pin 2 of the TVS tube D1 is connected to pin 1 of the resistor R11 and VC1_24V respectively, and pin 1 of the TVS tube D1 is connected to GND.

3. The comparator-based IGBT driver power supply according to claim 2, characterized in that: The PWM generating circuit comprises: an RC filtering circuit, a duty cycle adjusting circuit, a hysteresis threshold adjusting circuit and an output waveform adjusting circuit; The RC filter circuit includes: a resistor R12 and a capacitor C11; pin 2 of the resistor R12 is connected to VC1_24V, pin 1 of the resistor R12 is connected to pin 2 of the capacitor C11, and pin 1 of the capacitor C11 is connected to GND; The duty cycle adjustment circuit includes: a comparator U11C, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a capacitor C12 and a diode D12; Pin 2 of the resistor R13 is connected to Pin 2 of the capacitor C11, Pin 1 of the resistor R13 is respectively connected to Pin 2 of the resistor R14 and Pin 9 of the comparator U11C, and Pin 1 of the resistor R14 is connected to GND; Pin 1 of the resistor R17 is connected to Pin 2 of the capacitor C11, Pin 2 of the resistor R17 is connected to Pin 14 of the comparator U11C, Pin 1 of the resistor R16 is respectively connected to Pin 3 of the diode D12 and Pin 2 of the resistor R17, and Pin 2 of the resistor R16 is respectively connected to Pin 1 of the diode D12 and Pin 2 of the resistor R15; Pin 1 of the resistor R15 is connected to Pin 1 of the capacitor C12 and Pin 8 of the comparator U11C, and Pin 2 of the capacitor C12 is connected to GND; The hysteresis threshold adjustment circuit includes: a comparator U11B, a resistor R19, a resistor R110, a resistor R18, a resistor R1, a resistor R112, a capacitor C14 and a diode D13; the pin 1 of the resistor R1 is connected to the pin 2 of the capacitor C11, the pin 2 of the resistor R1 is connected to the pin 2 of the comparator U11B, the pin 3 of the diode D13, and the pin 2 of the resistor R112; the pins 1 and 2 of the diode D13 are connected to the pin 1 of the resistor R112, the comparator U11B ... Pin 9 of the comparator U11C is connected; Pin 2 of the resistor R18 is connected to Pin 2 of the resistor R17, and Pin 1 of the resistor R18 is connected to Pin 5 of the comparator U11B; Pin 2 of the resistor R19 is connected to Pin 2 of the capacitor C11, and Pin 1 of the resistor R19 is connected to Pin 4 of the comparator U11B; Pin 2 of the resistor R110 is connected to Pin 2 of the capacitor C14 and Pin 1 of the resistor R19 respectively, and Pin 1 of the resistor R110 and Pin 1 of the capacitor C14 are connected to GND; The output waveform adjustment circuit includes: a comparator U11A, a resistor R114, a resistor R113, a resistor R115 and a capacitor C15; pin 1 of the resistor R114 is connected to pin 2 of the capacitor C11, pin 2 of the resistor R114 is connected to pin 2 of the capacitor R115, pin 1 of the resistor R115 is connected to GND, capacitor C15 is connected in parallel with the resistor R115, pin 2 of the capacitor C15 is respectively connected to pin 2 of the resistor R115 and pin 7 of the comparator U11A, and pin 1 of the capacitor C15 is connected to GND; pin 1 of the resistor R113 is connected to pin 2 of the resistor R1, and pin 2 of the resistor R113 is connected to pin 6 of the comparator U11A.

4. The comparator-based IGBT driver power supply according to claim 3, characterized in that: The DC / AC conversion circuit includes: a voltage stabilizing filter circuit, a power amplifier circuit, and a field effect transistor drive circuit; The voltage stabilizing filter circuit includes: a voltage stabilizing tube D4, a resistor R116, a resistor R117 and a capacitor C17; the pin 2 of the voltage stabilizing tube D4 is connected to VC1_24V, the pin 1 of the voltage stabilizing tube D4 is connected to the pin 1 of the resistor R116, and the pin 2 of the resistor R116 is connected to GND; the pin 2 of the resistor R117 is connected to the pin 1 of the resistor R116, the pin 1 of the resistor R117 is connected to the pin 1 of the capacitor C17, and the pin 2 of the capacitor C17 is connected to GND; The power amplifier circuit includes: resistor R118, resistor R119, resistor R120, resistor R121, transistor Q11, transistor Q12, transistor Q13, transistor Q14, voltage regulator D15 and voltage regulator D16; pin 2 of resistor R118 is connected to pin 1 of capacitor C17, pin 1 of resistor R118 is connected to pin 1 of comparator U11A, pin 1 of resistor R119 is connected to pin 1 of comparator U11A, pin 2 of resistor R119 is respectively connected to pin 1 of transistor Q11 and pin 1 of transistor Q12; pin 2 of transistor Q11 is connected to pin 2 of transistor Q12, pin 3 of transistor Q11 is connected to pin 1 of resistor R120, pin 2 of resistor R120 is connected to pin 1 of transistor Q11 and pin 1 of transistor Q12. Connected to pin 1 of capacitor C17; pin 3 of transistor Q12 is connected to pin 2 of resistor R121, and pin 1 of resistor R121 is connected to GND; pin 1 of transistor Q13 is connected to pin 1 of resistor R120, pin 3 of transistor Q13 is connected to pin 1 of capacitor C17, and pin 2 of transistor Q13 is respectively connected to pin 2 of transistor Q14 and pin 2 of transistor Q11; pin 1 of transistor Q14 is connected to pin 2 of resistor R121, and pin 3 of transistor Q14 is connected to GND; pin 2 of voltage regulator D15 is connected to pin 1 of capacitor C17, and pin 1 of voltage regulator D15 is respectively connected to pin 2 of voltage regulator D16 and pin 2 of transistor Q13; pin 1 of voltage regulator D16 is connected to GND; The field effect transistor driving circuit includes: capacitor C8, capacitor C29, capacitor C210, resistor R222, resistor R223, resistor R224, resistor R225, resistor R226, transformer L21, diode D27, diode D28, voltage regulator D29, voltage regulator D210, voltage regulator D211, voltage regulator D212, transistor Q25 and transistor Q26; pin 2 of capacitor C8 is connected to pin 1 of capacitor C17, and pin 1 of capacitor C8 is connected to pin 6 of transformer L21. Connect, the 10th pin of transformer L21 is connected to the 1st pin of resistor R222, the 2nd pin of resistor R222 is connected to the 2nd pin of voltage regulator tube D16; the 2nd pin of resistor R223 is connected to the 2nd pin of transformer L21, the 1st pin of resistor R223 is connected to the 1st pin of transformer L21; the 1st pin of resistor R224 is connected to the 4th pin of transformer L21, the 2nd pin of resistor R224 is connected to the 5th pin of transformer L21 and GND respectively; the 1st pin of resistor R223 is connected to the 2nd pin of R225 respectively, the diode D The 1st and 2nd pins of the resistor R224 are connected to the 2nd pin of the resistor R226, the 1st pin of the diode D28 and the 2nd pin of the diode D28, the 1st pin of the resistor R226 is connected to the 3rd pin of the diode D28, the 1st pin of the voltage regulator D210 and the 3rd pin of the transistor Q25, respectively; the 2nd pin of the resistor R223 is also connected to the 1st pin of the voltage regulator D210 and the 3rd pin of the transistor Q25, respectively; the 1st pin of the resistor R224 is connected to the 2nd pin of the resistor R226, the 1st pin of the diode D28 and the 2nd pin of the diode D28, the 1st pin of the resistor R226 is connected to the 3rd pin of the diode D28 and the 1st pin of the voltage regulator D211, respectively. Pin 2 of the voltage regulator D211 is connected to pin 2 of the voltage regulator D212, and pin 1 of the voltage regulator D212 is connected to GND; pin 2 of the transistor Q25 is connected to VC1_24V, pin 3 of the transistor Q25 is connected to pin 2 of the transistor Q26, and pin 3 of the transistor Q26 is connected to GND; pin 2 of the capacitor C29 is connected to VC1_24V, pin 1 of the capacitor C29 is connected to pin 1 of the capacitor C210, and pin 2 of the capacitor C210 is connected to GND.

5. The comparator-based IGBT driver power supply according to claim 4, characterized in that: The output circuit includes: an isolation transformer T31, a diode DA3, a diode DA4, a diode DA5, a diode DA6, a diode DA7, a diode DA8, a diode DB1, a diode DB2, a diode D9, a diode D10, a voltage regulator D7, a voltage regulator D8, a resistor R31, a resistor R32, a resistor RA36, a capacitor C33, a capacitor C31, a capacitor C13, a capacitor C12, a capacitor C16, a capacitor C348, a capacitor C15, a capacitor C32, a capacitor C336, a three-terminal voltage regulator U31 and a three-terminal voltage regulator U32; Pin 5 of the isolation transformer T31 is connected to pin 2 of the resistor R223, pin 3 of the isolation transformer T31 is connected to pin 1 of the capacitor C29, pin 8 of the isolation transformer T31 is respectively connected to pin 1 of the diode DA4 and pin 2 of the diode DA3, pin 9 of the isolation transformer T31 is respectively connected to pin 1 of the diode DA5 and pin 2 of the diode DA6, pin 7 of the isolation transformer T31 is respectively connected to pin 1 of the diode DB2 and pin 2 of the diode DB1, pin 1 of the isolation transformer T31 is respectively connected to pin 1 of the diode DA7 and pin 2 of the diode DA8, and pins 2 and 6 of the isolation transformer T31 are connected to GND2; Pin 2 of diode DA4 is connected to pin 2 of diode DA5 and pin 1 of resistor R32 respectively; pin 1 of diode DA3 is connected to pin 1 of diode DA6 and pin 2 of diode DB2 respectively; pin 2 of diode DB2 is also connected to pin 2 of diode DA7; Pin 1 of diode DB1 is connected to pin 1 of diode DA8; pin 1 of resistor R31 is respectively connected to pin 1 of resistor R32 and pin 2 of diode DA5; pin 2 of resistor R31 is respectively connected to pin 2 of resistor R32, pin 1 of resistor RA36, pin 2 of capacitor C16, and pin 1 of capacitor C33 +36V power supply; pin 2 of resistor RA36, pin 1 of capacitor C16, and pin 2 of capacitor C33 are all connected to GND2; After the pin 1 of capacitor C13, the pin 1 of capacitor C31 and the pin 1 of three-terminal voltage regulator U31 are connected, they are connected to the pin 2 of diode DB2; the pin 2 of capacitor C13 and the pin 2 of capacitor C31 are both connected to GND2; the pin 2 of three-terminal voltage regulator U31 is connected to the pin 1 of diode D9, the pin 2 of diode D9 is connected to the pin 1 of diode D10, and the pin 2 of diode D10 is connected to GND2; Pin 3 of the three-terminal voltage regulator U31 is connected to pin 2 of capacitor C12, pin 1 of capacitor C348, and +15V power supply respectively; pin 1 of capacitor C12 and pin 2 of capacitor C348 are both connected to GND2; Pin 1 of capacitor C15, pin 2 of capacitor C32, pin 1 of diode DB1, and pin 2 of three-terminal regulator U32 are connected, and pin 2 of capacitor C15 and pin 1 of capacitor C32 are connected to GND2; Pins 2, 3, 6, and 7 of the three-terminal regulator U32 are connected together; The 5th pin of the three-terminal voltage regulator U32 is connected to the 2nd pin of the voltage regulator tube D8, the 1st pin of the voltage regulator tube D8 is connected to the 2nd pin of the voltage regulator tube D7, and the 1st pin of the voltage regulator tube D7 is connected to GND2; Pin 1 of the three-terminal regulator U32 is connected to the -15V power supply and pin 2 of the capacitor C336 respectively, and pin 1 of the capacitor C336 is connected to GND2.

6. The comparator-based IGBT driver power supply according to claim 1, characterized in that: The IGBT driver power supply is powered by a 24V-0V DC power supply, with an input current limit of 2A and an input voltage limit of 28V.

7. The comparator-based IGBT driver power supply according to claim 1, characterized in that: The PWM generating circuit is powered by an internal VC1_24V power supply, which is powered by a secondary RC low-pass filter. The hysteresis threshold is set to 16V and 8V, the PWM duty cycle is 50%, and the period is 10us.

8. The comparator-based IGBT driver power supply according to claim 1, characterized in that: The DC / AC conversion circuit is powered by a VC1_24V power supply, which, after voltage stabilization, supplies power to the DC / AC conversion circuit.

9. The comparator-based IGBT driver power supply according to claim 1, characterized in that: The output current of the output circuit is 500mA, and the total output power is 15W.

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