From: "Terrell W. Fritz"
Date: Thu, 31 May 2001 22:54:17 -0600
Subject: Re: [TSSP] Secondary in motion
Hi Paul, Using my Tesla coil tuner: The secondary system frequency is 252.91kHz. The primary system is 242.31kHz and the cap is 27.7nF so the inductance would be 15.575uH. The frequencies were measured with the secondary in place. However... I turned the quench time to a small value and measured the secondary ring down frequency when the primary circuit was open and got 238kHz for the secondary frequency. http://hot-streamer.com/temp/TerryCW/2001-5-31/Tek00005.gif http://hot-streamer.com/temp/TerryCW/2001-5-31/Tek00003.gif Not that there are some harmonics present in the waveform still!* I then removed the secondary and looked at the primary ring down frequency and got 218kHz. http://hot-streamer.com/temp/TerryCW/2001-5-31/Tek00004.gif It used to be simple tuning this stuff but with all these new effects it is getting complicated :-)) *The harmonics are caused by the solid state gap only turning "half" off. It is an IGBT in parallel with a diode: http://hot-streamer.com/temp/TerryCW/2001-5-31/Tek00008.gif You can see the diode still pushes a little current out in the expanded trace above. This affects the secondary frequency some so I looked at it far out in the ring down where the diode is off: http://hot-streamer.com/temp/TerryCW/2001-5-31/Tek00007.gif Now the secondary is at 242kHz. So... It looks like during actual operation that the primary frequency is 242 or 218kHz. The secondary is 253 or 242kHz. I guess I am a bit confused now :-)) But maybe the data above is what you wanted or your can point me in the direction and way the things should be measured... Cheers, Terry At 11:51 PM 5/31/2001 +0100, you wrote: >Terrell W. Fritz wrote: > >> I wound up a temporary primary to your dimensions above and >> set it up with the small coil: > >Ah, was hoping you might :) > >> Given that the tuning may be a little off > >Looks like it is. If you can measure the inductance of the improvised >primary, I'll match the model to it. > >Cheers, >-- >Paul Nicholson, >Manchester, UK. >--
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.