3 phase inverter schematic diagram?

Lots of ways:

You can get small VFDs on ebay for about a hundred bucks.

Jim Hanrahan has a how-to if you want to roll your own....

Note that there is just such an inverter in a Kitchen-Aid mixer (matched to the mixer motor, of course).

I Think he is looking for a Converter, not an Inverter. To convert single phase to three phase you can use transformers.

Now, *THATS* one I'd like to see.

If all you have is single phase, I'd like to see you make three phase with just transformers.

You can make three-phase with a three-phase motor by running it unloaded on the single phase. But the amount of power is limited by the motor size and phase-phase regulation is a bit dodgy.

daestrom

Look up 'Scott-T transformer'

Not perfect, but they work.

Bill Kaszeta Photovoltaic Resources Int'l Tempe Arizona USA snipped-for-privacy@pvri-removethis.biz

Hello, and I would suggest you study up a bit on the Scott connection. It was/is used for 3-phase to 2-phase (0 and 90 degrees) transformation. McGraw-Hill's "Standard Handbook for Electrical Engineers" is a very good reference source for this and other topics regarding electric power generation and distribution. Sincerely,

John Wood (Code 5550) e-mail: snipped-for-privacy@itd.nrl.navy.mil Naval Research Laboratory

A Scott connection can also be used for 3-phase to 3-phase with delta or Y on the primary and secondary. The advantage is only 2 transformers but they have to be derated because the power factor is lowered.

I don't see how Scott helps the OP.

bud--

"Bill Kaszeta / Photovoltaic Resources" wrote in message news: snipped-for-privacy@news.west.earthlink.net...

I know all about Scott-T. And that is *not* single phase. It requires two phases that are displaced by 90 degrees. You won't get that with two wires.

Scott-T also requires a tap at about 83% for one transformer and a center-tap on the other.

daestrom

Then come over here and I will show you because I have done it more than once. Three phase to Single phase doesn't require a damn thing. All you do is drop one of the legs (don't use it). Also do that all the time.

Ponder it.....

AEC Electric & Controls Michael Richardson snipped-for-privacy@sbcglobalremoveme.net

Read your own post, !!!

You said you could convert *single* phase into *three* phase, not the other way around. You have *not* done that with just a transformer, or you're the first person in the known world to do so.

Show me a circuit that can convert *single* phase to *three* phase using just transformers.

Ponder *THAT*

daestrom

It requires 3 transformers and I will dig out the schematic soon.

We're all waiting!! Remember you said 3 phase out--1 phase in. We'll even let you use 240/120, (single phase center-tap). Some wrongly refer that as two phase.