IGBTs good for DRSSTC

EDY19, Sun Oct 01 2006, 04:24PM

I want to make a "simple" DRSSTC if that is not an oxymoron smile and have come across some IRG4pc40 IGBT's for a fairly good price. It says 600V 49A on the datasheet with a rise delay of 26ns, rise time of 18ns, fall time delay of 240ns and a fall time of 170ns. What would be a good frequency to shoot for with these IGBTs, I know reaching has a small DRSSTC based on them at 280kHz, and it looks pretty nice! On second thought, would these work decently in a SSTC, then I could 'upgrade' to a dual resonant in the future? I'm going for a SSTC similar to Steve Wards SSTC2, which originally uses IRFP260s
Re: IGBTs good for DRSSTC
Part Scavenger, Sun Oct 01 2006, 04:51PM

Could you give us a link to the datasheet? That would give us more info. That would also give a better idea of SSTC/DRSSTC switchover-ing. :)
Re: IGBTs good for DRSSTC
EDY19, Sun Oct 01 2006, 05:05PM

Here is the datasheet:
Link2
Re: IGBTs good for DRSSTC
Steve Ward, Sun Oct 01 2006, 10:42PM

Just be careful of the extra long turn off delays. You will most likely need to add your own dead-time so that you dont get cross-conduction of the half-bridge. The turn off is fairly slow, im not sure i'd run them much past 150khz. Its certainly possible to go for more, but then your switching becomes less and less ZCS, so that could be a potential problem. Make sure you get the IGBTs with the diode inside (part number should end in D). Otherwise you have to add your own diodes, which isnt nearly as convenient.

I dont know if id really recommend my SSTC2 design anymore. If you want a DRSSTC, just build it as a DRSSTC (you already have a pretty nice SSTC anyway, right?). Primary current feedback is far more reliable than secondary antenna feedback of the SSTC2. Also, the control logic is a little different for DRSSTCs, so converting from SSTC to DRSSTC is a pretty substantial change.
Re: IGBTs good for DRSSTC
EDY19, Mon Oct 02 2006, 02:03AM

I think I'm going to use Avalanches SSTC PLL PCB, I've always wanted a coil with audio capabilities, and use a full bridge of IRFP260s, keeping it a normal SSTC. I found that your SSTC2 Circuit worked fine, Steve, As I had 16 inch sparks with 170VDC and antenna feedback.