how solve short circuit problem and dip of igbt gate voltage

[Maloth Ramesh]

i have problem while simulating the pspice model of ir2136 and based inverter with sine-pwm technique with 20khz switching frequency first one is control circuit second one is power circuit
my problem is source voltage is short circuiting for a duration around 1micro second
the gate voltage is continually deceasing.
igbt type fgh40n60smd, snubber circuit diode is rhrp30120, zenor diode is 1n4744,
and the voltage across the ITRIP terminal is increasing within 500micro seconds of operation


thank you,

 

[FvM]

source voltage is short circuiting

means exactly what?

You have unsuitably low impedance snubbers, I think. It's also not clear if the deadtime generated by the IR2136 internally (provided it's correctly modelled) is sufficient. You may want to add deadtime in your pwm generator.

Regarding overcurrent detection, I don't see "return_gnd" connected to the control circuit.