A New Walking Pattern SVM Technique for Five-Phase Motor Drives

As multi-phase motor drives become more popular and practical, new research in this area investigates potential advantages including lower torque ripple and better power density. The added dimensions of a multi-phase machine leads to a completely different operating nature than standard three-phase machines and merits research into new modulation methods. The five-phase and six-phase machines have been traditionally studied in the literature applying voltage-source modulation methods such as sine-triangle modulation and space- vector modulation for current harmonic elimination. Recent research of five-phase induction motor drives addressed nearest three vectors switching; which adds current harmonics but lowers torque ripple and considerably extends the drives voltage range. This paper introduces a new walking pattern SVM method which frees up the vector and sequence selection. The new method is demonstrated using detailed simulation and is shown to further reduce torque ripple.