3 Phase Motor Operating By Single Phase Motor

You tell us! It would be great if you can do it!!

PLEASE GO THROUGH ''http://www.sciencedirect.com/science/article/pii/S0378779604001440''

Try using a single-phase to three-phase inverter unit, perhaps?

Or

Resale value of 3phase motor + cost of inverter =/> New single phase motor.

That only works if the motor is 380V star. Then he can wire it in delta and he's OK. If it's 380V delta he needs a step-up transformer - more expense.

Or you could use the search function in the upper right and find that this has been answered many times on CR4....

All i can say is with single-phase supply maximum capacity of motor upto 2.2KW is used, above which three phase is used.

Such general statements in this discipline are often time misleading and just are plain wrong. Perhaps in your neck of the woods, anything over 2.2KW is normally three phase, such is not the case by any stretch of the imagination in many other places.

Here is a link to a single phase motor made by Baldor Electric. It is a single phase 15HP motor. Which works out to be about 11.2KW.

Click Here

If there was no demand for this product, do you think it would be manufactured and sold?

I dont think its economic to use 1phase,15HP motor with FLA of 66, when we got 3phase 15HP of FLA 21. I wonder why there is a demand for such a motor when the distribution system is very user friendly as 3phase is very available.

I agree with you that I would not use such a motor either, unless forced to. There are lots of places in rural North America where only single phase consumer services are available. This motor is often used on farm applications such as barn cleaners and the like.

My comment looks more to the fact that general statements on what is or is not "normal" in this industry are often negated by the reality of a given circumstance.

Good answer, most farms do not have 3 phase, which is a shame because they really could use it.

I think our tendencies towards hyperbolic assumptions scares off more people with than we help sometimes... but then again, cryptic incomplete questions foster that.

Promod98, if you are still with us...

There are ways to accomplish what you may be looking for, but with such little information it's difficult to make reasonable suggestions. If you really want help you must fully state your problem, i.e. size of motor, type of machine, voltage of the power supply, why you cannot replace the motor with a single phase version etc. etc. You are not limited to 140 characters nor are you charged by the word here, feel free to ramble!

Pramod,

it is not professional to do this, but if you have no other choice, theoritically you can do it,

1st solution: use a VFD 230 v single phase input, you will get 3 phases max 200v output, your 380V motor will run only at half speed.

2nd solution : you can use one coil of the 3 as main coil and the other two with appropriate capacitors as starting coils, in a sort that your set of capacitor will create a dephasing of +120 deg and -120 on the coils respectively....I did this long time ago on a 1.5kw I got only the third of the motor power, with a bad starting torque

it is not easy to determine the correct value of dephasing capacitor, you should know all the data of the motor, and proceed to complexe calculation .

this is the answer to your question , the advice is don't do it, buy a single phase motor

How do you work out that at 200V a 380V motor will work at ½ speed? Speed is governed by frequency!

A 2 stage VFD could run the motor.

YES, What you said is true, VFD output will be in best cases 200v 50hz,

VFD should be programmed with another V/F CURVE, as it will be max voltage 200v, max frequency 25hz, to keep it the nearest to the motor curve