Re: New SSTC and topology in need of review

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

Original poster: John Keith <jskeith-at-interaccess-dot-com> 

Hi George,

    This circuit sounds very interesting. Would you please consider postig
it, either here or to the High Voltage list?

Thanks,
John K.


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, December 15, 2003 5:55 PM
Subject: Re: New SSTC and topology in need of review


 > Original poster: "gtyler" <gtyler-at-drummond-dot-org.za>
 >
 > Hi, That's basically what I am talking about: A royer cct is a push-pull
 > topology with a tuned load (no mag. current) fead from a choke to give a
 > constant cycle to cycle current into a centre tap.
 > There is a capacitor from drain to drain, i.e. across the load. In my
 > induction Bearing heater the current from 220V mains is 25A rms but the
 > load sees 40A at 800V or 32Kva. All this with 2 cheap IGBTs.
 >
 > George
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Monday, December 15, 2003 4:59 PM
 > Subject: Re: New SSTC and topology in need of review
 >
 >
 >  > Original poster: dhmccauley-at-spacecatlighting-dot-com
 >  >
 >  >
 >  > This is similar to the circuit I have been working on except I'm not
 > using a
 >  > transformer to step up the voltage.
 >  > My current design (which is the one Steve Ward referred to) basically
 > is a
 >  > push-pull MOSFET switch acting purely linearly (not in saturation)
 >  > and designed to modulate the output of a MOT up to 500kHz or more.
 >  >
 >  > The circuit works almost flawlessly in linear mode producing a
 > sinewave
 >  > output up to 2400VAC -at- 500kHz, but because it is linear, the MOSFETs
 >  > dissipate
 >  > significant heat.  I'm currently trying to use the same type circuit
 > to act
 >  > in saturation mode for a nice square wave output, but am currently
 > having
 >  > some difficulties
 >  > with the gate switching.
 >  >
 >  > I'm about finished one month of my three month tesla coil hiatus (need
 > a
 >  > scheduled break!), so probably in March i'll pick up the many projects
 > I've
 >  > left off this year.
 >  >
 >  > Dan
 >  >
 >  >
 >  >  >      Interesting cct. However,would it not be simpler to use a
 > lower
 >  >  > voltage output and a transformer to give a higher voltage if you
 > need
 >  >  > it. This started me thinking, I have a royer type circuit that
 > produces
 >  >  > 800V rms SINE WAVE across a load at some 25A using igbts. (IR4GPH50
 >  >  > 1200v DEVICES).
 >  >  >
 >  >  > George
 >  >  >
 >  >  >
 >  >  >
 >  >  >
 >  >  >
 >  >
 >  >
 >  >
 >
 >