Re: The Next Coil

From: 	Greg Leyh[SMTP:lod-at-pacbell-dot-net]
Sent: 	Friday, August 01, 1997 5:25 PM
To: 	Tesla List
Subject: 	Re: The Next Coil

Tesla List wrote:

> >I do believe that DC Tesla coils are inherently more efficient for two
> >reasons:
> >
> > A)  Better power factor
> >
> > B)  With DC, _every_ firing of the primary ckt is at full energy, keeping
> >     the streamers continuously ionized
> >
> > -GL
> Greg,
> Do you think that the use of AC along with a synchronous gap would
> match the DC efficiency?  Maybe 120 BPS is a little slow, but using
> 3 phase AC with a sync gap, 360 BPS would be obtained and may
> be good?

Hmmm...  It's true that the '3 phase - sync gap - 360 BPS' system would
have a better power factor, but such a scheme would require three
primary capacitor banks and a rather novel commutating arrangement on
the rotary gap.  I wrestled with this design choice on my present coil,
and decided that a diode set would be easier to deal with than three
primary capacitor banks and a three phase rotary gap.  It's also very
convenient to control the thruput power using the rotary gap speed, 
which eliminates the need for high power variacs.