How to over come dv/dt effect on IGBT

[nareshgtr]

dv/dt

Dear Friends,
I am new to the power electronics. I designed 3-phase bridge using SGP23n60UFD IGBTs, FAN3788 used as driver circuit. Due to dv/dt the lower IGBT is turning on (shoot through). The IGBTs going bad. How to over come dv/dt effect.
Regards
V. Naresh Kumar

 

[Dmitron]

dv/dt parasitic inductance

I use a schematic(resistor + transistor in emitter), wich turn off the transistor than current becomes big.

 

[FvM]

overcome dt

I have no personal experience with the said FAN7388 driver, but according to the specification, it should be able to operate the IGBTs safely without additonal precautions.

How do you know, that shoot through is actually damaging the IGBTs? Are you able to measure the IGBT currents? I would rather expect a problem of overvoltages caused by parasitic inductances and inappropriate wiring.

 

[cachapo]

why dv/dt in power electronics

Hi nareshgtr,

you can try putting a low value resistor (just a few ohms) in the gate of the upper IGBT, in order to slow its turn on.

Another option : choose a driver that gives lower current to the gate of the IGBT.

Good luck.