Re: 1.5 res was Re: Improved Model for a Primary Charging CKT

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

Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net> 

Hi Gerry,

Comments in the text.


 > Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net>
 >
 > Hi Robert,
 >
 >  > Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>
 >  >
 >  > More thoughts on this.
 >  >
 >  >  > Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>
 >  >  >
 >  >  > The cap voltage consists of a series of terms:
 >  >  > vc = vss + vtr1 + vtr2 + vtr3 + .........etc
 >  >  >
 >  >  > vss is the steady state response, vtr1, vtr2 etc are the transient
 >  > responses
 >  >  > from each sg conduction.
 >  >  >
 >  >  > vss is constant sin with a f equal to the supply f and an amplitude
 >  >  > determined by V R L and C
 >  >  > vtr's are damped cosines determined by the R L C frequency and
decay
 > by
 >  >  > R/gap losses.
 >  >  > ie vss has the same f as the supply and vtr is the f of R L C.
 >  >  >
 >  >  > vss is known.
 >
 >
 >
 >  > Consider what we would like the solutions to have.
 >  >
 >  > 1. It should repeat at the supply frequency.
 >
 > I'm thinking that the firing voltage is not only function of the line
freq,
 > but also the resonant freq of the LRC circuit which may negate the desire
to
 > be periodic with the line frequency.  The beginning of a new transient
will
 > start when the SG quenches so I'm thinking there are too many other
 > variables that are asynchronous to the line frequency.

You may have misunderstud my equation.
vcc is the cap voltage, Its peak is the firing voltage.
 >From the equation vc is, as you say, a function of both the line frquency
and LRC frequency ie vss and vtr respectivly.

Yes not all solutions will be periodic with the line frequency.
I was specificly looking for ones that are. Because there are simply to
analyse.
ie do the easy cases first and move on to the hard ones later.
However I know belive they have the  biggest bang size.
 >
 >  > 2. At SG conduction the cap current should be zero.
 >
 > Do you mean when the SG stops conduction (ie, at quench)

No I mean when the SG starts to conduct the cap charge current is zero.
If the cap current is not zero the cap has not reach maximum voltage or it
has and its discharging.
If its still charging when the sg fires then at the beginning of next cycle
the current will intialy be the wrong way.
So in either case it not the max cap voltage.
The more unipolar the charge current is the lower the rms current for a
given charge.
The better the power factor.
I was trying to find ideal solutions that have the biggest bang size.
ie any other solutions have smaller bang sizes or are at less than twice the
supply frequency.
 >
 >  > 3. Unipolar charge current.
 >  >
 >  > I think constraint 2 removes the memory of pervious conductions.
 >
 > The only memory, I think, would remain is current thru the NST inductor.

Yes that what I was trying to explain with my poor expalanation.

 >  >
 >  > The  very large C case is not interesting in its self.
 >  > But it does suggest a solutions were C is between 1 and 2 times
resonance.
 >  >
 >  > For example if vss is a is almost a cos while vtr has a lower
frequency.
 >
 > For LTR?

Yes. More precily at a specific ratio (approx 1.5) to the res cap case the
charge current is zero when the sg fires.
I beleive its more unipolar than the resonat case(only fron a schetch) and
has a bigger bang size. (I need to to the maths for certainty as they are so
close).


Bob