Re: OLTC primary loss measurement

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

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bert.hickman-at-aquila-dot-net>

Hi Terry,

Did you ever make an estimates of capacitor ESR?? Gotta' believe those
flimsy leads also add a fair amount of series resistance in the primary
circuit...

-- Bert -- 
-- 
Bert Hickman
Stoneridge Engineering
"Electromagically" (TM) Shrunken Coins!
http://www.teslamania-dot-com

Tesla list wrote:
> 
> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
> 
> Hi Paul,
> 
> I was not able to find any time to work on this yeasterday.  But today...
> 
> The 20,40,60...  Volts I gave is a "metered" voltage.  The actual firing
> voltage is twice that number.
> 
> If  Rpri =  2 x pi x F x L / Q
> 
> Vfire   Qpri    Rpri
> 
> 40      4.7     0.0197
> 80      7.3     0.0127
> 120     10.0    0.00927
> 160     12.1    0.00766
> 200     14.0    0.00662
> 
> So the graph looks like:
> 
>         http://hot-streamer-dot-com/temp/OLTC09-02-01.gif
> 
> If one uses your equations below which seem to fit very well:
> 
>         http://hot-streamer-dot-com/temp/OLTC09-02-02.gif
> 
> Looks like I can expect a Q of 21.4 at 4.3mOhms for Rpri.
> 
> Vds Seems high here at 8 volts.  Probably not too surprising given that so
> many terms are at work in the "real" system.  However, if we pump 2000 amps
> peak into the system, the loss for Vds is:
> 
> 8*2081 = 16648 watts peak
> 
> While the loss for Rpri is:
> 
> 2081^2 x 0.00662 = 28668 watts
> 
> The system peak power is about 200*2081 = 416kW
> 
> Of course, 416000 /(16648 + 28668) = Q = 9.18 here in my guess work.  Off
> by the square root of two...
> 
> I will have to think about if Rpri or Vds has any reason to be so high.
> Have to think about cap and Lpri second order resonances and other horrific
> things...   Probably still have enough drive there in any case, but I just
> like to know exactly "why"...
> 
> Cheers,
> 
>         Terry
<SNIP>