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RE: Self-Resonant SSTC topologies
Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com>
A poster asked what was the prejudice against using IGBTs in SSTCs. As far
as I know, IGBTs were simply too slow until about 6 months ago. They could
not be used in SSTCs without special soft-switching schemes like Vladimiro
Mazzilli's Royer SSTC.
But the technology has advanced very quickly, and the newest ones from
Fairchild are almost as fast as MOSFETs, free from dynamic latchup, and have
a MOSFET-like square safe operating area too. This means they can just be
dropped into an ordinary H-bridge and driven as if they were MOSFETs.
Also K.C. said:
>Be sure to provide a big enough container for receiving your
>burned-out transistors. I'd suggest a 55 gal. oil drum.
If you go about things carefully, build your H-bridge with good bypassing
and low-inductance layout, tune carefully to avoid leading power factor, and
gradually work up to your design power, checking waveforms as you go,
there's really no need to massacre legions of transistors. (Unless you
decide to overdrive everything to get bigger sparks.)
But I supposee us second-generation SSTCers are kind of spoilt. People like
Richie Burnett, Gary Johnson, Jan Wagner, Alan Sharp, and K.C. have already
done the pioneering, made the mistakes for us, and written nice websites
telling us what not to do.