TSSP: List Archives

From: Paul
Date: Fri, 01 Jun 2001 11:17:46 +0100
Subject: Re: [TSSP] Secondary in motion

Marco Denicolai wrote:

> Terry (or Paul), would you mind sending me the values of
> Ces and Les of the coil we are talking about?

For the secondary with primary in place but open circuit, I get

  f1 = 244.5 kHz,
 Ces = 22.6 pF
 Les = 18.7 mH

For the primary alone, ie secondary removed altogether, I get

 Lp = 15.6 uH
 Cp = 27.16 nF
  f = 244.5 kHz

The above Cp is a little different to Terry's actual 27.7 nF - I
fiddled my value slightly to set the primary Fres to match the
secondary.

Now, when the system is put together, I get the main mode frequencies,

 f- = 209.0 kHz
 f+ = 299.9 kHz

Terry's measured primary values are,

 Lp = 15.575 uH
 Cp = 27.7 nF
  f = 242.31 kHz

and for the secondary,

  f1 = 252.91 kHz

so that the real coil appears to be slightly out of tune as well
as over-coupled, whereas the modeled version over-coupled but
the tuning is pretty close. 

I'm going to adjust the model's Ctop slightly to bring the model's
secondary f1 into line with the real coil, and similarly for the 
primary free resonance. Then the model will be equally out of tune,
and I'll recompute the dual resonator response once more.

Hopefully we'll get a better match with that rather complicated over-
coupled and out of tune waveform.  The comparison at present is
quite good on the mode amplitudes, but the phase is all over the
place.

More to follow on this later, 

Cheers,
--
Paul Nicholson,
Manchester, UK.
--


Maintainer Paul Nicholson, paul@abelian.demon.co.uk.