RE: Residual charge left on caps

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

Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com> 

In my simulations, I am able to make the cap-to-cap differences arbitrarily 
large.  I could see units developing asymmetrical charges as a function of 
leakage or capacitance, but the degree of asymmetric charge was always 
precisely offset by a comparable discharge, with no net change across 
cycles.  I did not attempt to simulate it, but I believe that only by 
having a means of rectification, could a charge grow over multiple cycles.

I don't know what "dialectric tensor" is.  Coronal rectification is the 
tendency for corona current to flow more-so when a coronal charge is one 
polarity over the other.  This occurs when the electrodes are dissimilar - 
one more pointy and one less-so, and is the underlying mechanism for the DC 
static charge that is deposited on our secondary forms and shocks us after 
the power is turned off.  But please, the archives are full of that topic 
so let's not go there.

Regards, Gary Lau
MA, USA


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

Hi Gary,

In practice, we experience the effect with a gazzion cycles.  I wonder if
more simulation cycles need to be done before seeing an accumulation.  Also,
could you explain coronal rectification?  Does it have something to do with
the dialectric tensor?

Gerry R
Ft Collins, CO



  > Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com>
  >
  > A while back I performed some MicroSim simulations to try to see what
could
  > be causing such a thing to occur.  I did include unequal leakage
  > resistances as well as unequal capacitances, but I was unable to get any
  > cumulative charge to build over multiple mains cycles.  It's got to be
  > something non-linear, like coronal rectification.
  >
  > Gary Lau
  > MA, USA