Re: Designing an optimized Magnifier
Hi Antonio and All,
I use a 220K resistor in series with a 5pF capacitor as an arc load in ALL
my TC models. This load seems to work very well for my small coil all the
way up to Greg Leyh's giant Electrum coil. This was discussed in the past
and there are good reasons why this simple two element load will simulate
almost any TC (or maggie) type arc. It has never failed me yet!
I have played a little with magnifier models but I don't have anything
profound to say. The standard TCs seem to consume all my time and I have
never really gone too deeply into magnifiers. However, my MicroSim models
should be easily adaptable to such a system especially with such good
knowledge of magnifiers and TC models these days. All the basic elements
are there but it is just a matter of doing it...
I don't have any plans on working with magnifiers in the near future but
if anyone wants to work on magnifiers and MicroSim models I would be more
than happy to help with any questions or "advice" in the effort...
Magnifiers seems to be just waiting for such analysis but I am too busy
with other stuff these days...
I think the addition of "real" losses, actual driving elements and some
parasitics will change the analysis from "theoretically pure" to
"realistically practical" rather easily.... A lot of work, but it is just
begging to be done. I wish I had the time to get into it...
The element values usually need to be actually measured... Theory is
"nice", but unless you have a "real" scope waveform to be sure you are on
the right track, you can spend days on something that is far from
realistic. My gap modeling is all based on real measurements and when I
finally figure it out it will be obvious, but you need to base all that
modeling stuff on real data or you will get quickly lost. At the moment,
my gap measurements and what I have been able to figure out theoretically
do not match. However, the real measurements keep me from wasting time on
things I "think" should be right but are NOT! The effects of the primary's
self capacitance is something I never would have thought of if the
measurements did not force me to look there! Modeling is so powerful that
it can do anything, including the impossible, with ease... You need real
data to keep it all real. Unfortunately, it take fancy test equipment to
get much of that data. I have obviously spent far more in test equipment
than anything else in my work...
However, when the model works, it is bazaar how WELL they work. My recent
power factor correction and gap timing predictions were completely based on
what the models told me. When I finally got the hardware in place, the
actual performance was just as predicted! My LTR coil was ALL modeled and
predicted far before it was demonstrated. It would have taken years (if
ever) to do such a complex coil system by trial and error. I was able to
get the exact parts I needed and they worked the first time without waste
(except the parts I fried when I turned it up to far :-)) But models
predicted that to!!
Of course, it is wonderful having great theory too... Right now, I could
use a little more spark gap theory. Or, I need to look at that darn
measurement system to be SURE it isn't lying to me! :-))
At 09:51 PM 8/4/99 -0700, you wrote:
>Bert Hickman wrote:
>> Great summary and waveform examples, and a special thanks for
>> discovering and correcting the formula errors from the original
>> Bieniosek papers! If you were to include the effects of typical gap and
>> other system losses (N/I streamers), do you have any recommendations for
>> a specific combination of k,l,m to obtain best practical performance?
>The first paper had expressions with errors that I didn't identify,
>but a correct equation for L3/L2, that was missing in the second
>paper. The second paper had also an error in the expression for L1C1.
>The expression for k12 I deduced from the second paper, that consider
>the coupling adding L2 and L3.
>The effect of gap and streamer losses is difficult to assert,
>as the equivalent resistances depend on many parameters.
>Apparently, the 1,2,3 combination is the most efficient regarding
>resistive losses in the coils, as it results in oscillations of
>lower frequency for a given transfer time, what reduces losses due
>to skin effect in the wires and irradiation.
>(But this may require larger inductances, and so more wire, and
>I didn't find any reference to these different magnifier regimes,
>other than the Bieniosek papers, that mention only the 123 and 125
>systems. Other configurations are very probably something never
>I will try to add losses to the examples that I have simulated
>to see if there is some significant difference in the effect of
>losses in the different modes (but I will have to think about a
>realistic way to compute equivalent resistances representing
>I will also make available a simulator that can compute element
>values for the several configurations and plot easily the waveforms.
>Antonio Carlos M. de Queiroz