Re: Please help ! IGBT exploded ...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Sean Taylor <sstaylor-at-uiuc.edu> 

On Mon, 08 Mar 2004 19:52:16 -0700, Tesla list <tesla-at-pupman-dot-com> wrote:

>Original poster: "Rajesh Seenivasan" <rajeshkvs-at-hotmail-dot-com> Hi Mike,
>
>The bottom transistor on one leg of the H bridge exploded. (It shows short).
>The gate drive waveform of top and bottom igbts crossed each other at 0
>volts
>and increased from 0 to +/-5 volts in 800ns (very slow rising edge ?).
>I had 3.3 ohm resistor in series with gate.

Sorry, forgot to mention, +/-5 volts is a pretty low voltage for a gate 
drive - should get to at least 10V, and totally switch from one voltage to 
the opposite (on to off or off to on) in under several hundred nS - 
depending on how good your driver is at achieving ZCS.  Try using a good 
high current gate driver chip like the TC4420, or TC4421/2, or there's a 
couple TI chips, but I've never used them.  I can't remember the part 
number off the top of my head, though I think Steve Ward's site (on 
hot-streamer) has the info . . .

Sean Taylor
Urbana, IL