Re: three phase coiling

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

Original poster: Greg Leyh <lod-at-pacbell-dot-net> 

Solid-state primary switching might be the best way to get the timing 
resolution you require for accurate 3-phase RF control.  I'll have a better 
idea within a few weeks what degree of control such a 'phasing' knob has on 
the output arcs of a twin coil.  The phasing control for the ALF prototype 
will have a resolution of about 200nS, on a 16uS period Fo.

-GL


>Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net>
>I've been running some interesting simulations, in respect of having 3
>basically identical (but slightly different) coils running simultaneously,
>near each other, to see if you could get triangular or Wye sparks.
>
>The first cut is to try and force the coils to run 120 deg out of phase with
>each other (RF phase, not AC charging).  I worked out some LC networks and
>such that can do this (you basically create something that looks like a
>phase shift oscillator network), but I suspect that as the sparks grow, the
>loading will change the frequency enough to perturb the situation.
>
>[snip]
>
>I suspect that any sort of spark gap system will have enough jitter in it
>that precisely synchronized firing (we're talking tenths of microseconds,
>here) is unlikely to occur.  In fact, one can help things along a bit by
>providing some loose coupling with a phase shift between the primaries, and
>running a triggered/rotary gap  on one primary and static gaps on the
>others.  As the first coil fires, the voltage change in it will raise or
>lower the voltage on the other coil (depending on if it's leading or lagging
>coupling), and cause it to fire a bit early or late, making the RF out of
>phase.
>
>Comments?