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From: wreck@fmsrl7.UUCP (Ron Carter)
Newsgroups: sci.electronics
Subject: Re: 1 phase to 3 phase conversion
Summary: It can be done somewhat messily.
Keywords: phase conversion
Message-ID: <39787@fmsrl7.UUCP>
Date: 10 Apr 91 21:25:44 GMT
References: <1991Mar28.191005.1653@rodan.acs.syr.edu> <3613@polari.UUCP> <4725@osc.COM>
Reply-To: wreck@fmsrl7.UUCP (Ron Carter)
Distribution: na
Organization: Ford Motor Company, Scientific Research Labs, Dearborn, MI
Lines: 18

One quick and dirty method of producing 3 phase from 1-phase
power is to connect a 3-phase induction motor as a delta winding
and then run one side off the line power.  It can be started
using a big starting capacitor along one of the other two
sides.  Once it is running, the motor's inertia provides the
necessary energy storage and the magnetic field of the armature
induces currents in the non-driven windings.  The result is a
pretty close approximation to "real" 3-phase power available
across the 3 motor terminals.

Of course, for this you pay in hysteresis losses, resistive
losses in the windings and armature, and windage losses in
the bearings and cooling airflow.  Electronics are definitely
superior for everything except tolerance to electrical abuse.
The nice thing about the motor method is that motors are
much more likely to be lying around in usable condition.

Yes, I'm a real EE.