Re: Solid State Egg of Columbus Driver - Circuit Review Requested (fwd)

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Date: Sat, 28 Oct 2006 15:50:11 -0700
From: Ed Phillips <evp@xxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Solid State Egg of Columbus Driver - Circuit Review Requested (fwd)

Cameron,

   I know you are building this to operate on single phase, so this 
might not help, but you or someone else might get some good ideas from 
it, that could help. They used to supply old 2-phase loads from 3-phase 
systems using Scott connections, which take specially wound 
transformers. I'd photographed and posted on my web site, some pages 
from a General Electric Distribution Transformer Manual some time ago 
for another discussion. The very last ones show 3, 4, and 5 wire Scott 
connections, including phase angles. You can see these at:

http://murrayranch.com/Electricity.htm


You would most likely have to wind your own transformers.

Don"

	Phase conversion with a Scott T or similar transformer configuration requires polyphase power to start with and if he had that he would be home free!

	As for that EDN article, it would certainly work but using square wave drive to the amplifier bridges would work better (transistors either in saturation or open circuit) with much lower transistor dissipation.  I didn't pay attention to the original circuit using flip flops but that should be much easier and simpler to build, and can certainly be made to work.

Ed