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Re: 3-phase current - you don't need caps or ider motors!
"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
course. One transformer is centertapped, the other transformer has a
tap
placed at the 86.6% point. I will place the schematic and text on my
web
page in the next day or two and I will notify the list when it's there.
This is
such a handy thing for high-power coilers to know how to do.
Bert Pool"
IF you already have a two-phase power source, and I am not aware of any
in use these days, you can use the Scott Tee to covert from two phase to
three phase, and vice versa. Trick is getting the two-phase power
source to begin with. We're talking about single-phase power here, and
there isn't any practical way to convert reasonable amounts of power to
three phase with a static device. For small currents a capacitor phase
shifter, or better a capacitor-inductor phase shifter, will work.
Ed