[Prev][Next][Index][Thread]

Matching capacitor size to transformers



Hi All,

I was pondering how to best predict what size capacitor would go with what
size NST.  Also, given a NST and capacitor size, what would be the break rate.

I have come up with the following two equations based on many things:

	0.92 x ( Vo x Io - L ) / ( BPS x Vo^2 ) = C

	0.92 x ( Vo x Io - L ) / ( C x Vo^2 ) = BPS

Vo = Transformer RMS output voltage (volts)
Io = Transformer RMS output current (amps)
L = known system loss (mostly protection filter resistors) (watts)
BPS = Breaks Per Second
C = Capacitor value in Farads

The second equation is just a slight rearrangement of the first.

C is the largest cap size that a fine tuned LTR coil can charge.  Static
gap and other systems would be less but at least this provides an upper
limit.  The BPS equation my predict what the BPS of a static gap system
with say resonant charging might be.  

This equation is meant to fill a void in my MMC program.  The MMC program
is good at arranging small caps to make a given capacitor, but many people
don't know what value of capacitor they need...

The equation comes from how much energy a transformer can deliver and how
many times per second it can charge a cap of a given value.  The 0.92
factor comes from my observations of my coils and basically is adjusting
for system loss.

Comments??

Cheers,

	Terry