Irregular windings in wound rotor induction motors

The importance of using regular windings in polyphase wound rotor induction motors is stressed in this paper. Harmful effects upon the efficiency, power factor, breakdown torque, and noise of the motor may result with an irregular winding, due to differential leakage. The Goerges diagram of tooth fluxes is presented for studying this phenomenon. Means of avoiding trouble of this sort also are pointed out. It is further observed that 3-phase motors having a number of poles which is a multiple of 6 are most likely to be troublesome.