Re: Photos of 8 kVA twin coil (fwd)

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Date: Mon, 28 May 2007 10:03:49 +0200
From: Finn Hammer <f-h@xxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Photos of 8 kVA twin coil (fwd)


> 
> Hi Finn,
> 
> There are small breakouts (about 1/8") on each toroid, set to break at 
> about 95% full drive.  Without the 1/8" breakouts, the toroids allow no 
> spark!  As the design evolves, the entire equator of the toroids will be 
> equipped with active breakouts, which can be activated and deactivated 
> at will.

Cool, I built a coil for the lightning storm room at Danfoss Universe, 
here in Denmark. It had 6 breakout points which are operated by 
pneumatics, and sequenced from the show controller.
It is a great addition to a coil show, to be able to direct the 
streamers at will.

snip
> 
> Yes, each primary is a single turn.  In fact, the transverse component 
> of the conductors inside the driver circuitry make up about 20% of the 
> effective primary loop.  This design also uses the Regenerative Tesla 
> Coil scheme described earlier, where the remaining ringdown energy in 
> the secondary is recovered back to the primary capacitor, after the 
> secondary voltage decays to the point where it no longer contributes to 
> the streamer growth.

I did a bit of reverse engineering of the primary circuit, with 
dimensions extrapolated from pictures and videos.

Suppose the primary is a bit over 40" in diameter.(2,6mH)
Zsurge = 0.98
Suppose the primary cap is around 2,7µF (18*0,15µF)
Firing voltage = 4kV ?
Fres =60kHz
Bang energy = 21,6J
Pri Current =4076A
Power at 400BPS = 8640W

With 4kA Ipri, and anyways, I am sure that if you should decide to post 
pictures of the inside of the black box containing primary switch gear, 
then these pictures will have an audience. At least with this list member.

Cheers, Finn Hammer