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.

Investigation of the Properties of a Five-Phase Induction Motor in the Introduction of New Fault-Tolerant Control

“…Section 4.2 describes the input power characteristics for all conditions based on mechanical torque and constant engine speed. These waveforms (Figures [12][13][14] show that in the event of a one-phase failure, the nominal torque must be reduced by 22.86% in order to maintain the same input power as in normal operation. We reduced this to 12.86% for unbalanced currents and 8.58% for symmetrical currents by using fault-tolerant control.…”

“…According to the waveforms in Section 4. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17], the rated motor torque must be reduced by 59.43% in order to maintain the original power load of the motor phases. When using fault-tolerant control on nonsymmetrical currents, they are reduced by 57.15% and symmetrical currents are reduced by 30.85%.…”

“…When connecting to a pentacle, the authors mention that this connection is not suitable for operation in the event of a failure of one phase. A comprehensive evaluation of the behavior of a five-phase induction motor in hazardous conditions is given in [12]. The result of the article is that the most advantageous compromise for the design of the drive is the pentagon connection.…”

Practical Implementation of the Indirect Control to the Direct 3 × 5 Matrix Converter Using DSP and Low-Cost FPGA

“…The multiphase drives are gaining significant popularity in recent times, due to the higher torque density [ 1 ] and the property of the fault-tolerant control possibility [ 2 , 3 , 4 , 5 ]. This gives them a significant advantage in safety-critical applications, such as trains, elevators, cranes, and hospital applications.…”