A Comprehensive Investigation of the Properties of a Five-Phase Induction Motor Operating in Hazardous States in Various Connections of Stator Windings

Abstract

This paper examines the properties of a multi-phase drive for EV (electric vehicles) and HEV (hybrid-electric vehicles) using a simulation model in the Matlab/Simulink environment and verifies the findings by experimental measurements on a real motor. The paper studies a five-phase induction motor, a suitable alternative for electric vehicles, due to its better properties such as better torque, smoother ripple, better fault tolerance, and the possibility of connecting stator windings to star, pentagon, and pentagram. The fundamentals of the article are to find out how this engine behaves in fault states, which can be called hazardous states. The paper presents a comprehensive evaluation of the decrease of mechanical power, torque, and power losses during motor operation without failure, in case of failure of one phase, and in case of failure of two adjacent phases and two non-adjacent phases, in different connections. In the simulations, the five-phase drive is powered from an ideal five-phase voltage source to verify the behavior of losses on the motor in fault conditions. Subsequently, the motor model is powered by a five-phase VSI, while the simulated waveforms are confirmed on a real motor, which is also powered by a five-phase VSI. The investigation results are the detection, which of the stator windings has better properties in the fault-free state and the case of fault states in operation. For which stator windings connection, it is most advantageous to design and dimension a five-phase induction motor.