Re: 3-phase current - you don't need caps or ider motors!

To: tesla-at-pupman-dot-com
Subject: Re: 3-phase current - you don't need caps or ider motors!
From: bertpool-at-ticnet-dot-com (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Sat, 12 Dec 1998 12:40:38 -0700
Approved: twf-at-verinet-dot-com

Date forwarded: 	Thu, 10 Dec 1998 14:00:19 -0700
Date sent:      	Thu, 10 Dec 1998 11:33:48 -0700
To:             	tesla-at-pupman-dot-com
Subject:        	Re: 3-phase current - you don't need caps or ider motors!
Forwarded by:   	tesla-at-pupman-dot-com
From:           	Tesla List <tesla-at-pupman-dot-com>

> Original Poster: "Jim Lux" <jimlux-at-jpl.nasa.gov> 
> 
> > I knew I had this somewhere, but it took me a while to find it.  There is
> a
> > way 
> > to change 2 phase power to 3 phase using only two transformers!  It is 
> > called a Scott transformer, and was used by power companies to go from 2 
> > phase to 3 phase or 3 phase to 2 phase power.  You do not have the puny 
> > power limitations of capacitor systems, nor do you have to use a large 
> > motor/generator setup.  I found this in my 1939 Coyne home electrial 
> 
> 
> The Scott connection requires true 2 phase power, with the phases 90
> degrees apart. Residential service is, of course, center tapped single
> phase.  You can make the 90 degree phase shift with capacitors, but then,
> why not just make 3 phase power. 
> 
> For driving a power supply, an RC phase shift network like they use in
> welders has to be the way to go. No moving parts, etc. Sure, the phase
> balance gets terrible at low loads (why you wouldn't want to do this for
> running a motor), but for a power supply, it isn't even an issue. I'll
> figure out the equations and post them in the next couple of days.
> 
> 

I'm disappointed this won't work with existing power systems, but we find 
and offer what we can to solve problems.  Maybe next time I'll be more help!

Bert Pool