Re: LTR cap BPS?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>



Hi Ed,

Very good question.  The firing only on positive cycles (or negative) was
first observed by me with a scope on the SG and my first thought was DC
flowing.  The simulations also show the same phenomenum and the model was a
linear one (no saturation effects modeled).  I would need to simulate this
again to refresh my memory,  but if I remember correctly, this mode would
flop to the other polarity in time.  I suspect that the steadystate and
transient responses ganged up to cause this for a period of time and then it
drifted into another mode.  At the time I was doing the simulations, I
thought I had a theory on why this was happening but it escapes me now.

Gerry R.



> Original poster: Ed Phillips <evp@xxxxxxxxxxx>
>
> "It also should be realized that
> the firing of a static gap is somewhat chaotic due to transient
> responses in
> the charging circuit due to the gap firings (easy to see with a
> simulation)
> and any breakrates can be obtained by changing either the gap setting
> and/or
> the Cp value.  It doesnt necessarily lock onto 120 BPS.  With a given
> design
> and gap setting you often will get some half cycles that do not fire and
> other half cycles that fire multiple times,  You can also get periods of
> time where only the positive cycle (or negative) will fire"
>
> I've never used a scope to look at the NST voltage while a gap is
> firing, but see all of this behavior in my EWB simulations.  The most
> interesting thing is the firing on only positive or negative cycles.  To
> me that implies that there is DC flowing from the transformer and that
> there should be core saturation effects associated with that which the
> simulation doesn't include.  Any thoughts on the subject?
>
> Ed
>
>