H bridge transistors on one heat sink?

Hi!
I am making an h bridge which will generate sine pwm at the output. Im using 4 igbts for h bridge and these are to be mounted on heat sink. Here i have a problem. If i connect all igbts to one heat sink they will create electrical short circuit since drain of all the igbts will be electrically connected to heat sink. Do i need separate heat sink for all igbts? Any solution for this problem? I used thermal pads too but the metallic screw connecting igbt still connects the heat sink.

You can buy insulating kits for most kinds of transistor to solve this problem. TO 220 mounting kit is one example, but as you don't say which transistor you are using I can't say which is the correct kit for it.

Rishi_kesh:
Hi!
I am making an h bridge which will generate sine pwm at the output. Im using 4 igbts for h bridge and these are to be mounted on heat sink. Here i have a problem. If i connect all igbts to one heat sink they will create electrical short circuit since drain of all the igbts will be electrically connected to heat sink. Do i need separate heat sink for all igbts? Any solution for this problem? I used thermal pads too but the metallic screw connecting igbt still connects the heat sink.

You forgot to get the proper mounting kit with insulating top-hat washer…

My igbt is TO 220 package. So i need insulating kit for it. Thanks, i will buy it.