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Re: Transformer
- To: tesla@xxxxxxxxxx
- Subject: Re: Transformer
- From: "Tesla list" <tesla@xxxxxxxxxx>
- Date: Fri, 08 Apr 2005 17:09:29 -0600
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- Resent-date: Fri, 8 Apr 2005 17:20:31 -0600 (MDT)
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Original poster: Finn Hammer <f-h@xxxx>
Alex,
You appear to be where i was only a year ago. At that time, I had great
assistance from this small publication:
http://www.easternvoltageresearch.com/datasheets/plasmasonic_testing01.pdf
which is the instructions for the Plasmasonic board made by Daniel McCauley.
But to answer your question, the Fet`s/IGBT`s should conduct crosswise,
1: left up, right down conducting (current trough coil one direction)
2. none conducting (called dead time)
3: left down, right up conducting (current trough coil other direction)
If you have:
left up, left down conducting, there is a short across the rails. this
situation is called shoot trough. You`l recognize it imediately, because
that`s when the devices explode, and fly all over the place. Happened 13
times to me, before I got the picture. Luckily, fet`s were cheap.
The primary coil is connected to the mid-points of the silicon´s, and
controlling the devices like this, shifts the polarity to the primary coil.
The coil is connected to the + or - rail by a conducting device. By
controlling the devices like shown, the polarity across the primary coil is
alternated at the driving frequency, which should be the secondary res. freq.
This is how you create the alternating magnetic field, which lures the
secondary into pumping electrones on and off the topload.
This topload, which is by good fortune, both mechanically so large that it
withstands high potentials without breakout, but also electrically so
small, so that even a moderate current will cram electrones onto it with
such relative abundance, that extremely high potentials are reached.
I said lure, because there is resonance in the secondary at the frequency
used in the primary. Power is applied, but hardly any force is involved.
This whole resonance thing, not at all unlike intercourse in a waterbed.
Hope this helps.
Cheers, Finn Hammer
Tesla list wrote:
Original poster: "Alexander Turkin" <alex_3@xxxxxxx>
Hello!
My question is about gate drive transformers in the H-bridge SSTC. For
example, in Richie Burnett's circuit (or any else)
For example, if the left upper MOSFET is turned on, what another MOSFET
should be turned on (the right upper or the right lower)? I've seen both
variants in the internet. But what is correct?
Thanks
Alex