Predictive Torque Control for Five Phase Induction Motor Drive with Common Mode Voltage Reduction

Abstract

Multiphase induction motors are used in application requiring high reliability, fault tolerance and reduced per phase power. Common mode voltage (CMV) in induction motor (IM) drives causes winding insulation failure, bearing leakage current and acts as source for electromagnetic interference. This paper presents finite state predictive torque control (PTC) for two level five phase induction motor in order to reduce the CMV. A new cost function is formulated to reduce CMV and total harmonic distortion (THD) and increase efficiency retaining the dynamic performance and variable speed operation of the drive. The performance of drive is analyzed with different voltage vectors applied to aforementioned constraints (CMV, current THD and efficiency) in cost function. Experimental results and analysis confirm the validity of the applied algorithm.