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Re: Voltage Multiplication Circuits



Output voltage is N times the peak input voltage, where N is the number of
caps (or diodes).  So, with 2 diodes and caps you get a doubler, the output
being 2.8 Vrms. With 4, a quadrupler, 5.6 Vrms, with 6, a sextupler at 8.4
Vrms

If you are driving it with a pulsed waveform (say, like in a TV high
voltage circuit, or with an inverter, or a flyback), it is N* Vpeak.. 

Also, as the number of stages increases, the time to reach full voltage
gets longer and longer (the charge has to get bumped up the chain each
cycle of the input, and each time, less of the charge gets moved). A 50
stage multiplier (yes, I built one, ONCE, zillions of solder joints,
etc.).. takes many hundreds of cycles to reach equilibrium.

For a practical HV supply, I think that a many 10's of kHz switching supply
driving a multiplier chain is a nice way to go. Low stored energy, etc. 
For running off line frequency, it's a tough go, and you'd probably be
better off with a more classic cascade arrangement with stacked
transformers.

The other nice application for a voltage multiplier is charging a big
discharge cap.  When the output is heavily loaded (the discharge cap is not
charged), the output voltage of the multiplier is low, but who cares, all
the current is going to the cap.

----------
> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Voltage Multiplication Circuits
> Date: Tuesday, November 09, 1999 4:11 PM
> 
> Original Poster: Boombast99-at-aol-dot-com 
> 
> I would be interested to know what the voltage progression is per bridge
i.e. 
> if the xformer is 15KV then is the voltage 30KV after the first
bridge,60KV 
> after the second etc. or what ? Also what would the cap and rectifier
values 
> be........? Counting on you Jim !!!!!
>                                Thanks ,Dan
> 
>