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RE: NST TEST GRAPHS (was NST power test)



Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>


While Richard Hull's measurements are interesting, his paper contains a 
fallacy.. the shunts don't "start to come into effect"... they're there all 
the time, along with the leakage reactance they produce.

Perhaps you really need to measure the reactive and active powers 
separately (current probes on the cap and resistor with an oscilloscope 
would do nicely..)

 From a power transfer standpoint (which might not be what you want), you 
want the "conjugate match".. that is, considering the source as a series 
combination of an inductor (leakage inductance) and a resistor(copper 
losses, in this case, referenced to the secondary side)

you'd want the load to be the equivalent of a series resistor of the same 
value and a capacitor of equal reactance.


   (magnetizing inductance and core losses don't apply for the matching 
condition..)


In your setup, you've got a a parallel RC, which you'd need to transform 
(mathematically) to the equivalent series circuit..

What we want in a TC, though, is a bit trickier.. it's not a steady state 
sinusoidal circuit, but, rather, a transient one, where you are charging a 
capacitor through an inductor and resistor.  I suspect that a time domain 
simulation might be a better way to approach the problem.

The measurements of NST output with RC loads, though, will give you a good 
way to confirm that a linear model of the NST as a resistor and inductor is 
a good one.




>Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
>
>Hi John,
>
>I have been doing tests too :-))  Although still very rough draft like, it
>is at:
>
>http://hot-streamer-dot-com/temp/NSTva.html
>
>It is not done yet, but I thought I would mention it now for
>suggestions.  I could only get 260VA out of a 360VA NST using just
>caps.  Any ideas are welcome ;-))  It is all set up and just waiting.