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Re: Pole Pig Simulation

Hi Bart,

        I think the key here is to keep it "real" and keep the "current down".

In other words, try to use values and situations that are "real world" and not
some "wild fantasy" that good o'l MicroSim can cook up.  MicroSim can handle
500 tetra-amp impulses with ease, but really "we" are not going to do that ;-))

The ONLY goal of all this power factor "noise" is to find a PFC cap value that
will minimize the AC current draw.  Voltage to current phase angles don't mean
much when the waveforms look like spaghetti chopped with an ax.  The little
doctor from Westinghouse gave use nice equations for sine waves, but what we
are dealing with is more in the "CPU time on a 500MHz pentium" stuff...  No
simple equations will apply!

I would try an concentrate on a real system (that you may have right there) if
things get tough.  Don't try to do too many variables.  Try and see the "big
picture" in all this modeling and how it can help us.  It is easy to get lost. 
I am just doing four NSTs with a static gap right now and then tackle the SRSG
with that nasty timing optimization next.  Pretty gnarly going here just on the
"easy stuff"...

However, the results are astounding and very valuable!!  Too bad we didn't do
this years ago.  But even back then, we knew this was NOT going to be easy!! 
Sorry to be a bit vague but I am sort of dog paddling for air here myself.  We
are pulling information out of Tesla coils that has not been seen before and it
is going to but up a big fight.  But, of course, that is what we are here for!


At 06:16 PM 9/6/00 -0500, you wrote: 
> Hi John C., Terry, 
> I'm having a real difficult time with pole pig simulations for power factor.
> The problem is the ballast. With a pole pig, it will easily draw massive amps
> without any current limiting. I've been reading both your responses and
> continue to integrate these more refined details to the similations. 
> With your methods, it necessary to identify the VAR's to calc PF. However,
> adding either series R, series L, or PFC, the phase angle between line V and
> I change. 
> Is it right to say that the PF could also be calculated this way: 
> (assume 1 cycle here) 
> Identify and the time of zero-crossing of line voltage; 
> Identify the time for zero-crossing of line current; 
> Then,  ARCCOS(Lead time / Lag time) = degree of phase angle? 
> This angle can obvisouly be leading or lagging depending on the circuit. 
> Again, a ballast really makes a mess of this. As L-Ballast is increased, the
> phase angle increases and it also limits current (therefore, any current or
> voltage reading past the ballast cannot be used for identifying a PF based on
> Volt-Amps or Watts). If the method decribed above will perform the same
> function, then I've got some interesting info about ballast PF correction,
> but if not I could sure use some ideas. 
> HELP!!!!, 
> Bart