On Tuesday, July 9, 2013 2:14:05 PM UTC-4, PrecisionmachinisT wrote:

Probably the most simple rotary converter design uses no switches, is self-starting, and consists of nothing but a single oil cap and a three phase motor.



Connection and operation is pretty much the same as what is commonly known as a "PSC" motor.



I've stumbled across schematics etc. for such an arrangement numerous times in the past, but I've never built or witnessed one in operation and so I can't really comment further except to say that I suspect it would probably start up slowly and / or tend to run somewhat on the warm side.

A good design for a rotary phase generator uses two motors. One is a three phase motor and the other a single phase motor. The two motors are connected by a variable belt drive so that the single phase motor is trying to speed up the three phase motor. It is self starting and with a few capacitors has a reasonably power factor ( meaning it will run on a lower amp breaker. ) But it takes up a lot more room than a VFD and does not give you variable speed.

Dan