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RE: rectifying
Greetings,
> -----Original Message-----
> From: Tesla List [mailto:tesla-at-pupman-dot-com]
> Sent: Wednesday, March 08, 2000 8:57 AM
> To: tesla-at-pupman-dot-com
> Subject: rectifying
>
>
> Original Poster: "Jan Florian Wagner" <jwagner-at-cc.hut.fi>
>
> Hi,
>
> I found a very compact 3kV 50mA NST, and thought about turning this into a
> fixed voltage (but non-regulated) DC HV power supply. I've a bunch of 5kV
> 40mA diodes waiting that should do the rectifying and voltage doubling
> part. But I've no clue how to do a cheap _HV_ rectifier... so I'd be
> grateful for any advice or schematics, or web site tips!
>
> The DC PSU would be connected to charge up a 8nF tank cap. What size
> should the smoothing cap be then? Does around 100uF sound reasonable?
> Less, larger?
>
> And, the problem is, how can I get 100uF or other at 2x4kVDC? And what
> type of cap would be ok?
> Is it a good idea to put ordinary "high" voltage electrolytic caps in
> series? Or AC motor starter caps perhaps?
>
> Other thing, does anyone know of a solution for this:
> 1) even while the SG is ignited, the smoothing cap should be charged up.
> And not be shorted out and discharged into the short.
> 2) when the SG quenches, there should be no limiting resistor
> between the 8nF tank cap and the smoothing cap. I'd want the
> 8nF cap to be charged up fast.
> Any way to do this?
>
> Many thanks!
>
> --
> *************************************************
> Jan Florian Wagner
> http://www.hut.fi/~jwagner
>
>
>
I am not quite sure what you are using the power supply for
however if you are wanting to use it in a TC then no smoothing
cap is necessary.
Do you want a full wave bridged rectifier?
4.24KV
This will give you both a positive and negative terminal
to work with, however takes twice the diodes. It also
will give you roughly twice the overall power, because
you will benefit from both the negative and positive side
of the AC wave. This I have not tried with a TC yet, only
because I don't have the other two diodes yet.
0------>|------------------- terminal 2
\ |
\----|<----- |
NST | terminal 1 |
/----|<----- |
0 \ |
\--->|-------------------
Or are you looking for a (half wave)/full wave rectifier?
2.12KV
Not sure if this is called a half wave, or a full wave
without the bridge part. However this one takes less
parts but wastes half of the sine wave.
---->|---------/- terminal 2.12KV
NST /
---->|-------/
You then need to pull a ground from somewhere, I have
just used earth ground for this and it works. I hook
one side of my cap up to earth ground and the other side
up to the dioded NST. Fires the TC just fine.
---------------------
If you are building a voltage doubler then there is some
more parts to add. Can you tell us what you are trying
to power.
It is kind of tough trying to draw schematic in ASCII (barf).
It probably is even tougher to read.
By the way you will need to parallel each of the diodes in
the schematic with the diodes that you have. Probably wouldn't
hurt to use three in parallel for each diode in the schematic.
One thing I like about a DC TC is that it sort of
protects your NST without a protection circuit.
Hope this helps,
Cheers,
Bill Parn