Re: The OLTC II lives!

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

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

Hi Ken,

At 10:37 AM 1/29/2004, you wrote:
>Admirable work, Steve!  And aren't you lucky to have a cooperative EE
>department nearby.  Mine is nearby all right (U.C. Berkeley) but without
>doubt that's about all--for this graduate of half a century ago.
>
>I note that you employ a "breakout" point.  What effect do you get
>without that?  I'd found, with my sstc when it was working, that I would
>get very much more sparking when the sparks issued directly from the 6" x
>24" smooth toroid rather than from a point (you may recall having seen a
>photo on hot-streamer/temp).
>
>No doubt that difference has much to do with the differing modes of
>operation:  In mine, I had to build up the secondary voltage over 20-30
>cycles before breakout whereas with yours, I'm sure most all of the power
>into the secondary is crammed into the first few cycles.
>
>I wonder if this difference would tend to support my conjecture that the
>relatively rapid rate of rise in a "spark-gap" type of coil enables a
>higher voltage to appear at the top electrode than would otherwise be the
>case.  That would be due to the physical inertia of air molecules in
>"getting out of the way" of the path of the spark, thus delaying the
>gross reduction in secondary Q resultant from the spark.
>
>Can any pundits (in addition to yourself!) shed light on this?
>
>Ken Herrick


In my case,  I found that the high coupling really helped get the energy to 
the topload fast in order to avoid losses.  If the coupling was low, all 
the energy would get eaten up by the losses in the secondary coil and 
such.  For a true CW coil, this is not an issue since there is always more 
power available.  The OLTC just has the energy stored in the primary caps 
to work with.

Cheers,

         Terry