Re: OLTC II- advice on tank cap

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

Original poster: "colin.heath4 by way of Terry Fritz <teslalist-at-qwest-dot-net>" <colin.heath4-at-ntlworld-dot-com>

hi steve,
             if you want a uk supplier r.s. components is the one. they have
the arcotronics caps very well proven in tesla duty up to .1uf and the 1500v
version has 1800v/us rise time ( i think thats right)
cheers
colin

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Tuesday, May 06, 2003 7:42 PM
Subject: Re: OLTC II- advice on tank cap


 > Original poster: "K. C. Herrick by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <kchdlh-at-juno-dot-com>
 >
 > Stephen-
 >
 > Take a look at my recent postings re:  A triggered-s.g. 1-turn primary/
 > Herrick's pizza-pan primary for perhaps some useful information.
 >
 > Ken Herrick
 >
 > On Tue, 06 May 2003 08:02:17 -0600 "Tesla list" <tesla-at-pupman-dot-com>
 > writes:
 >  > Original poster: "Stephen Conner by way of Terry Fritz
 >  > <teslalist-at-qwest-dot-net>" <steve-at-scopeboy-dot-com>
 >  >
 >  > Hi folks,
 >  >
 >  > I just received a nice pair of 1200V 600A IGBT bricks today. Thanks
 >  > Terry!
 >  > It gives me an evil feeling of power just looking at them. Now comes
 >  > the
 >  > hard part. I need to design a MMC cap that will store at least 2J,
 >  > preferably 5-10J, at 1000V. So we're talking between 2 and 10uF. You
 >  > might
 >  > think this is easy enough, but it needs to have very low inductance,
 >  > and
 >  > deliver a peak current that could be more than 10,000A.
 >  >
 >  > Proper film and foil caps seem to be out, because I can't buy them
 >  > in large
 >  > sizes. It would cost a fortune and be very bulky. So I'm thinking
 >  > metallized polypropylene. 10 to 50 of .22uF 1000V caps in parallel
 >  > would be
 >  > needed. Can anyone comment on this choice or suggest any particular
 >  > kinds
 >  > of cap? I used .47uF 500V LCR metallized film caps in my original
 >  > OLTC with
 >  > no problems. Even though they were only rated 40V/us but I ran them
 >  > nearer
 >  > 200. They got a bit warm though.
 >  >
 >  > Last of all, the construction, how should I arrange the caps for
 >  > lowest
 >  > inductance and even current sharing? If I had axial caps (leads come
 >  > out
 >  > the ends) I could drill a grid of holes in two copper-clad PCBs or
 >  > thin
 >  > copper plates, sandwich the caps between the plates, and solder them
 >  > in
 >  > place. Would this be a good layout, or would the caps in the middle
 >  > pass
 >  > less current than the ones at the edges?
 >  >
 >  > Your advice would be much appreciated,
 >  >
 >  > Steve C.
 >  >
 >  >
 >  >
 >  >
 >  >
 >
 >
 >