2 replies to this topic

[incal]

Hallo,

Is there a difference between the rotor of an 8 pole induction Mashine and a 4 or 6 Pole Induction Mashine.

Can there be performance degragation if I use 4 Pole rotor with 8 pole stator.

the Motor power 110 Kw. The stator is rewounded as 8 pole. But I dont have any rotor. I find economic 4 pole rotors for this type of configuration.

Motor working point is 5 Hz inverter controlled (for 8 pole 70 rpm )

can there be serious problems when I use 4 Pole rotor in this configuration and working point.



thanks
Incal.

[marke]

Hello incal

The rotor and the stator are wound in a seies of slots. The rotor has a different number of slots than the stator, and the rotor slots are skewed so that there is a continuous overlap. This reduces problems with sensitivity to harmonics and also overcomes cogging effects. The stator can be wound for a number of pole configurations without changing the number of slots. It is just how the coils are arranged and connected within the slots that determines the number of poles.
To use another rotor, you are best to look at the number of slots. If it has the same number of slots and the same skew, there will be no problem. If you end up with equal slots on the stator and rotor, then you will hve harmonic problems.
It is quite practical to change rotors in a machine for rotors with diferent starting characteristics.
Best regards,