A simplified model for induction machines with faults to aid the development of fault tolerant drives

Abstract

A new mathematical model of a three-phase induction machine, suitable for the simulation of machine behaviour under fault conditions is presented. The model employs a simple state space equivalent circuit based model of the induction machine, which is enhanced to include space harmonics and main flux saturation effects. The model has been improved by including a variation of machine inductances with rotor and flux position, and creates a simulation with reasonable accuracy and fast computation time. For healthy and fault conditions, comparisons show that the simulated saturation and space harmonic frequencies and magnitudes match those obtained from experiment. This model can be used to develop and optimise control strategies for fault ride through.