Re: High Inductance Secondaries and DRSSTCs

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

Original poster: "Steve Ward" <steve.ward-at-gmail-dot-com> 

Hey Dan,


On Thu, 09 Sep 2004 07:42:25 -0600, Tesla list <tesla-at-pupman-dot-com> wrote:
 > Original poster: "Eastern Voltage Research Corporation" 
<dhmccauley-at-easternvoltageresearch-dot-com>
 >
 > Does anyone remember the discussions that were awhile back regarding high
 > number of turn secondary coils???

No, but i assume some people would worry that it spoils the Q due to
wire resistances.

 >
 > I'm currently designing my secondary coil for my "Psychosis Coil" which will
 > be 48" winding length, 25 AWG, on a 12.5" Dia.
 > coilform.  About 2700 total turns.  Total Ls of the secondary is about 440mH
 > and resonant frequency of the entire secondary / toroid assembly is about
 > 30kHz.

Sounds good to me.  Thats like my coil, just much larger diameter.  I
used 26 awg on an 8" form and 45" tall.

 >
 > Right now, the only bad thing about this is i will need a larger number of
 > primary turns to get down to the resonant frequency I want (i plan on using
 > about a 0.3 to 0.4uF primary capacitor)

I think you can perhaps go to maybe .45uF.  The .36uF im using now
seemed to work the best for me, but your coil is both larger and a
lower frequency, so i think you will want a suitably larger capacitor.
  And you're using bigger IGBTs ;).

 >
 > Anyone else see anything troubling with my secondary???  I can't.  I should
 > have probably used a larger gauge wire (maybe 22 AWG), but i just bought
 > a 68 LB spool of this 25 AWG stuff.

I think it should work fine.  For a SGTC it might not be optimal, but
secondaries like this seem to work fine on DRSSTCs.

Steve

 >
 > Dan
 >
 >