# [TCML] Fwd: Re: Question for solid-staters

Slight error in the following: I reference R1 but that should be, of course, R3.
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KCH

-------- Forwarded Message --------
Subject: 	Re: Question for solid-staters
Date: 	Fri, 24 Apr 2015 15:48:41 -0700
From: 	Ken Herrick <kchdlh@xxxxxxxxx>
To: 	TCML <tesla@xxxxxxxxxx>

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More accurately, Re: Question for single-resonance solid-staters--of which there seem to be mighty few still around.
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Having been involved in deciding on series or parallel single-resonance with synchronized primaries (from secondary feedback), I've received good advice recently but have thought to make a simple simulation to further pursue it. Ref. the following link.
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https://dl.dropboxusercontent.com/u/28799314/TCRB3/KCH-Screenshot%20-%204_24_2015.jpg

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Two anti-phase drives of 300V each drive 2 identical primary coils. The transformer is a simulation of a Tesla coil (with the secondary inductance of my actual coil) and its top-load. The secondary Fr is what's calculated for those L & C values--absent any primary influence.
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In the chart, I started out at primary:primary k = 1 and primary/primary:secondary k = 0.8. Ran a 1ms simulation, measured the maximum, entered that into the chart, etc. Finding 35KV as the maximum in that column, I proceeded leftward then upward similarly, reaching the sweet spot of the one k = 0.9 and the other, 0.4. I then set R1 to 100K, just the once, and ran that again. That seemed to show that paralleling primaries closely together and setting a rather loose coupling to the secondary yields the best response (and the easiest way to do it).
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I just note I made an error on the chart, substituting +144K for *144K in the notation. Won't bother changing it...
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This seems to further tell me that I don't have to series the primaries to create 1 effective coil but rather can configure them just physically & electrically in parallel.
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