Re: OLTC update - Poor seconadry Q

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

> Although, MicroSim is pretty "unverified" for subtle streamer behavior, it
> is saying that the instantaneous power to the streamer and to heating the
> coil looks like this:
> 
> http://hot-streamer-dot-com/temp/OLTC08-31-01.gif

Ok, for your model.
 
> The red is the secondary heating power and the green is the streamer power.
> 
> However, if one looks at the voltage across a 3300 ohm series resistor in
> the secondary and the streamer voltage, the loss looks small:
> 
> http://hot-streamer-dot-com/temp/OLTC08-31-02.gif

Note that what appears over the resistor in one cycle, peak to peak,
is approximately what is missing in the next voltage peak. I didn't
check if the theoretical rule is this, but it's something like this.
 
> I wander if I initially have the power but there just is not enough there
> to keep the streamer going.  The sparks are more brush like too suggesting
> that is the case.

Really, if streamer formation depends on many cycles with the energy
trapped in the secondary system, this may be a problem. I don't
remember seing a study about this in this list. With Q=36 and 3300
Ohms of series resistance, the equivalent parallel resistance is
36*3300 = 118800, and the streamer with 220 kOhms is really not
contributing much for the energy drain.
 
> Secondary loss, streamer impedance, and....  Is one of those areas that is
> not terribly well understood.  Conventional coils seem to have just found
> the sweet spot but this coil seems to have found a "bad" spot.  We'll
> probably learn a lot before this is over :-))

A question is: What is important for streamer formation? High Q
secondary or a lot of energy available directly from the terminal?
For sparks to ground, the later is the answer, but for streamers it's
not clear.

> Mine is 6X too and Paul got a Q of 45 for the coil.  Has program can
> predict these effects to a reasonable degree.

So, proximity is really the problem. But to space-wind 0.5 H of 
inductance would be a big problem...
 
> Good point!  I may have made a giant corona machine there.  But I measured
> the Q at low power (signal generator) too.  But corona could certainly be a
> big factor at the high voltage...

You could make an experiment, wrapping a coil that has known 
characteristics and observing if its Q decreases.

Antonio Carlos M. de Queiroz