Modelling and Analysis of a Transfer Field Machine with Displaced Windings

Abstract

This paper presents the modelling and analysis of a Transfer Field (TF) machine with displaced windings. In this machine, there are two identical polyphase windings in the stator displaced by an arbitrary angle ε. The two component fields revolving in the airgap are of the same pole number and the speed of operation is inversely proportional to the sum of the two pole numbers, that is, half the synchronous speed $\frac{\omega }{2}$ of a normal induction motor. There is thus, a close relationship between the self-cascaded induction machine and the TF machine. The effect of displaced angle on performance characteristics of the machine was investigated in both dynamic and steady states. It is shown that the performance characteristics of the machine is optimum when the two polyphase stator windings are displaced by 25 electrical degrees. The maximum output power and starting torque increased by 136.8% and 25.3% respectively.