Modelling, design and analysis of multi-phase induction motor

Abstract

Three-phase induction motor is extensively employed for the high power drive application rated at several megawatts, such systems generally exhibit poor performances in terms of losses and torque pulsations. Additionally, power semiconductors devices of large voltage and current rating requires in high power applications, which are either expensive or unavailable. Due to the potential benefits of multi-phase technology, recently some interest has also grown in the area of multi-phase machine. In this paper, mathematical model, analysis, design and simulation of multi-phase machine are carried out. Performance investigations of six-phase induction motor is carried out under steady-state and transient conditions when fed from sinusoidal and non-sinusoidal supply mains. For high power variable speed drives applications, multi-phase motor is supplied through power converters and its simulation studies are also carried out. The simulation studies of conventional three-phase induction motor and multi-phase motor of same rating are carried out and its comparative study is made to find out its suitability for general purpose drives applications. Based on simulation study, the multi-phase machine offers numerous advantages over the conventional three-phase induction motor drives such as improvement of the torque quality, reduction of the stator current per phase, improvement of torque density and increase of the fault tolerance.