Power-on and power-off locking protection circuit of servo driver IGBT module

The invention discloses a servo driver IGBT module power-on and power-off locking protection circuit, which comprises an optical coupler, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor, a first voltage stabilizing diode, a first triode, a second triode, a third triode and an MOS tube. According to the invention, a digital signal power supply threshold value is set by the second resistor and the first voltage stabilizing diode, the first triode is switched off when the digital signal power supply does not reach thedigital signal power supply threshold value, the first voltage stabilizing diode is broken down when the digital signal power supply rises to the digital signal power supply threshold value, and thefirst triode is switched on, so that the on/off of the optocoupler is controlled through the on/off of the first triode so as to protect the optocoupler; and a comparison threshold value is set by thefifth resistor, the first