AC induction motor.... possible to have an odd number of poles?

Question

I have never seen such a motor with 3, 5, 7 poles etc. - always an even number. Why? Physically impossible?

Answer 1

Because motors works on a 50-50 winding + and - poles

If there is an odd winding do you think the armature will spin ? No Because the electricfield will cause the 1 pole to attract and there will be no turning force since the other opposite pole is important to  repetitive turning through the magnetic field.

As to make it simple odd poles no turning force

                               even poles will create turning force to the synchronization through the magnetic field.

Answer 2

check three phase motors?

Answer 3

I don't know of any induction motor with an odd number pof poles.Refer to www. 3-phase motors.

Answer 4

Poles have to be in pairs. One is positive while the other is negative.

Its actually better to use pole pairs in calculations and the way you will see it in many text books etc. but for some reason manufacturers like to state the number in poles.