Re: Voltage Multiplication Circuits

To: tesla-at-pupman-dot-com
Subject: Re: Voltage Multiplication Circuits
From: "Steve Cook" <Steve-at-g8cyerichmond.freeserve.co.uk> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Thu, 11 Nov 1999 17:23:41 -0700
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

I agree about the idea of using switched mode at higher frequencies. My own
experience of multipliers has been that they are a lot easier to get working
well in the range of 10 - 250kHz, although I must admit that I have been
working chiefly with circuits that produce outputs of less than 10kV.


----- Original Message -----
From: Tesla List <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, November 11, 1999 1:41 AM
Subject: Re: Voltage Multiplication Circuits


> Original Poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
>
> 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
> >
> >
>
>
>