Re: OLTC maggy

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

Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi Steve,

In general, the faster we can convert the low voltage high current primary 
energy into higher voltages and low currents somewhere (anywhere) else, the 
lower the losses will be.  In a magnifier, the second stage may be useful. 
to store energy longer with lower loss while the final primary can convert 
that energy into sparks.

There is a problem with getting even higher coupling than we have now.  We 
just don't have enough turns to get in the say 0.7 coupling area.  But we 
may be able to hit one of Antonio's "sweet spots".  This may also help the 
recharging problem you mention.

A magnifier may also be easier to tune since we have more freedom to play 
with the secondary frequency in a three coil system.

Cheers,

         Terry


At 09:54 PM 4/4/2003 +0100, you wrote:
>At 12:30 04/04/03 -0700, you wrote:
>>Original poster: "boris petkovic by way of Terry Fritz 
>><teslalist-at-qwest-dot-net>" <petkovic7-at-yahoo-dot-com>
>>
>>In adition to my previous post:
>>Has someone considered building "Off line 3 coil
>>system"?
>
>The coupling in a typical OLTC (well, both of the OLTCs that exist) is so 
>high that it might as well be a magnifier. Terry's and mine both quench 
>after about 3 cycles, suggesting a coupling around 0.25. Having said that, 
>if the energy transfer were speeded up even more, like to 0.5 or 1 cycle, 
>it could reduce "gap" losses. This is a good thing because the IGBTs are 
>probably more lossy than a real spark gap. Are transfer times this fast 
>possible with a maggie? Maybe ACMQ could advise us here?
>
>On the other hand, one of the problems I had with the OLTC was that the 
>secondary kicks back into the primary after turnoff, and partially 
>recharges the tank cap via the flywheel diodes. This interferes with the 
>charge circuit and makes the bangs smaller than they should be. The higher 
>the coupling, the worse this effect is. So on a magnifier it might be 
>unacceptable. It can be combated by just increasing the supply voltage, 
>but then if the cap were to start off fully discharged for some reason, 
>you'd blow something out.
>
>Steve C.
>