Re: Capacitor value not clear yet.

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 


Terry,

Ah, math is beautiful isn't it?

Max I = V / sqrt (L/C) using your values = 282.8 amps

Gerry R


 > Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>
 >
 > Hi Luke,
 >
 > The primary current is a function of the primary resistance, frequency,
and
 > inductance.
 >
 > If the resistance is 0.1 ohms and the inductance is say 100uH and we have
a
 > 20000 Volt primary cap at 20nF, we can find the peak current.
 >
 > The inductance will have a value Zl which is generally referred to as
 > complex impedance or reactance.  This acts much like resistance.
 >
 > Zl = 2 x pi x Fo x L
 >
 > Fo = 1 / (2 x pi x SQRT(L x C)) = 1 / (2 x pi x SQRT(100e-6 x 20e-9) =
112540Hz
 >
 > Thus  Zl = 2 x pi x 112450 x 100e-6 = 70.7 ohms
 >
 > The total impedance is Z = SQRT(R^2 + Zl^2) = SQRT(0.1^2 + 70.7^2) = 70.7
 > ohms.  The 0.1 ohms of resistance is very small compared to the 70.7 ohms
 > so it really does not make any difference here (but it does matter when it
 > comes to coil losses!).
 >
 > The peak current is the voltage divided by the impedance:
 >
 > 20000 / 70.7 = 282.88 amps.
 >
 > Cheers,
 >
 >          Terry