Re: Voltage multiplier capacitors (fwd)

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Original poster: Steven Roys <sroys@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Fri, 23 Mar 2007 15:40:15 -0700
From: Ed Phillips <evp@xxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Voltage multiplier capacitors (fwd)

It's a bit complex to figure out what size caps might be optimum for 
a hugely inductive source like a NST.     As the stack charges from a 
stiff low impedance, the current flow starts to look like narrow 
pulses (since it only flows when the transformer voltage is > the cap 
voltage, and so on, up the stack).  A ballasted source like a NST 
might act more like a constant current source, so the charging 
current waveforms might look different.

I'd just pick some caps of convenient values and build it and try it. "

	I've run Electronic Work Bench (spice derived) simulations in the past to study an inductive NST running a capacitive voltage multiplier.  Can't find the files but remember that I suspected it might be possible to get into resonant voltage rise problems and that one should use care in trying the idea.  Has to work for small capacitors of course but when they get into the 0.01 ufd region and above (to improve regulation) trouble may be brewing.

Ed