Re: DC Supply

To: tesla-at-pupman-dot-com
Subject: Re: DC Supply
From: Greg Leyh <lod-at-pacbell-dot-net> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Thu, 24 Sep 1998 04:16:31 -0600
Approved: terryf-at-verinet-dot-com

> Original Poster: Mark Finnis <mefinnis-at-medicine.adelaide.edu.au>
> 
> Hi Jim,
> 
> At 12:36 22/09/98 -0600, you wrote:
> 
> >In a classic three phase full wave bridge, you only need 6 diodes
> >because the transformers would be connected in delta. I'd have to think
> >about the implications of the grounded secondary centertap on this,
> >since it sort of makes your system connected in Wye.
> 
> No-one else commented on this & I lack the background theory (as you
> probably guessed !).  I assume I still connect all of the centre-taps to
> ground & this will not be a problem.

Remember, with center-tap grounded secondaries, the windings 
cannot be connected directly together in either delta or wye,
since now you will have *six* phases to worry about (2 per
CT'ed secondary).
Each secondary HT terminal must go to its own full-wave 
rectifier set (consisting of 2 stacks), and the DC outputs 
of the rectifier sets can then be bussed together. 

 ---------------------- +
             |_
             D^
             |
    HT ------o
(6 places)   |_
             D^
             |
 ---------------------- -

The resultant DC voltage will be symmetrical around ground.
-- 

-GL
www.lod-dot-org