Re: DRSSTC Primary Circuit Feedback Control

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Jimmy Hynes <jphynes@xxxxxxxxx>

Hi Terry,

The little IGBTs should be practical anyway. Based on some
measurements taken on my DRSSTC, I'm convinced that a half bridge of
little TO-247 IGBTs could get me to 5'.

You have to be a little careful with primary feedback, because if it
isn't tuned, the secondary won't be sucking much out, and it will
build up more than normal


On Mon, 06 Dec 2004 19:41:22 -0700, Tesla list <tesla@xxxxxxxxxx> wrote:
> Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>
>
> Hi All,
>
> I was looking at DRSSTC stuff today and I became worried that using the
> secondary base current for feedback control may place unneeded stress and
> the IGBTs...  So I am thinking of using the primary LC loop current instead
> to get "`exact" zero current crossing switching with very good timing.
>
> I wrote up an explanation of the idea here:
>
> http://hot-streamer.com/TeslaCoils/MyCoils/drsstc/DRSSTC-PriFeed.pdf
>
> With zero current crossing switching, the stress and dissipation on the
> IGBTs should be far less and using cheap TO-247 style IGBTs (IRG4PF50WD -
> $8) should be very practical.
>
> Cheers,
>
>        Terry
>
>