Mathematical Modelling of Multiphase Induction Machines Based on the Phase-domain Approach

Abstract

The study focuses on electromechanical energy conversion processes in induction motors with multiphase stator windings. Its aim is to develop a mathematical model using the phase-domain approach and to determine the optimal number of phases.

Mathematical modelling has progressed from phase-coordinate equations to orthogonal transformations and the vector space decomposition (VSD)\break method. While VSD simplifies control synthesis, phase-domain models provide better analysis of unbalanced and fault conditions.

A universal phase-domain model of a multiphase induction motor was developed, along with a method to account for changes in electromagnetic parameters when increasing the number of phases. Numerical simulations were performed in MATLAB 2024a.

Results show that increasing the number of phases raises the maximum startup torque and torque ripple. The startup time has a minimum at 5–6 phases. Considering manufacturability and inverter complexity, five-phase stator windings are recommended.