Re: the cure for racing sparks

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

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "Paul Nicholson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <paul-at-abelian.demon.co.uk>

> We just happen to have one of those :)
> 
> Modeling this situation, using dimensions for Marco's Thor system
> 
>  http://personal.inet.fi/atk/dncmrc/thor.htm
> 
> by way of an example, leads to the following time domain response.
> 
>  http://www.abelian.demon.co.uk/tssp/tmp/thor.wave.gif
> 
> with the animation
> 
>  http://www.abelian.demon.co.uk/tssp/tmp/thor.anim1.gif
> 
> This simulation assumes that there is no breakout until a certain
> topvolts threshold is reached.  At this point (40uS after firing)
> a discharge arc forms from topload to ground, and the arc is
> maintained for the rest of the event.
> 
> The resulting negative going transient propagates down the coil,
> rebounds from the bottom end, travels back to the top, where it
> again rebounds, and so on.   This is shown more clearly in this
> zoomed animation, which begins 100nS before the arc starts and
> shows the detail of the transient in slow motion,
> 
>  http://www.abelian.demon.co.uk/tssp/tmp/thor.anim2.gif
 
Nice simulations. The animated gifs appear to be or too large or
are confounding my browser in some way, but I could see the
idea. How is the model?
There is another effect that could be examined more
carefully: If a spark discharges the terminal while the energy
transfer is not complete, the secondary current may continue to
feed the arc for a long time. I have seen this happen in an
induction coil very clearly.

Antonio Carlos M. de Queiroz