RE: Tube regulator for removing ripple . . .

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

Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

But that high voltage with the capacitive filter is only the case when 
lightly loaded, so the cap voltage tracks Vpeak.  Under any sort of load, 
the voltage on a capacitor filter comes down a lot (unless you've got a 
really huge capacitor, and a really high current rectifier able to crank 
out the current at the peaks..

The choke input filter tends to sit more at the Vaverage out of the 
rectifier.  Also, if the 20H filter is wound with smallish wire, the series 
R will also affect the regulation.

At 12:00 PM 4/3/2003 -0700, you wrote:
>Original poster: "Mccauley, Daniel H by way of Terry Fritz 
><teslalist-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>
>
>
>Are you worried more about ripple or regulation?  I took a quick look at an
>ARRL handbook (1990 edition) and they give a guideline of Lcrit =
>Eout(Volts)/Iload (mA), so for 4000V and 1A, it would be 4H, a reasonable
>size for an iron core choke.
>
>Reference data for Radio Engineers gives a design equation of
>ripple/output = 0.83/(LC) where L is in H and C in uF
>
>plugging in your number of 10V ripple (RMS or peak?)
>10/4000 = 0.83/(4*C) >>> C = .83/4*4000/10 >>> C = .83*4000/40 = 83 uF
>
>But.. make that a 20 H inductor, instead of 4H, and you're down to 16-17
>uF...
>
>20H is certainly reasonable
>
>
> >>>>>An LC filter like this does reduce the ripple considerable (less than
>30V p-p) for a 20H series inductor and
>10uF capacitor, however with that huge inductor your output voltage now
>drops from about 3.2kV (capacitive filter only)
>down to about 2kV (with the 20H series inductor)
>
>The Captain