A Space Vector Based PWM Scheme for Realization of Virtual Pentagon, Pentacle Connections in open-end Winding Five Phase Machine Drives with Single DC Source

Abstract

This paper presents a Space Vector based Pulse Width Modulation (PWM) scheme for obtaining different virtual winding connections in a dual Inverter fed open end winding five phase machine drives with a single DC source. A five phase machine can have three possible winding connections named star, pentagon and pentacle. The winding changeover is a commonly used method to increase the voltage across the stator windings in a machine so as to extend the operational speed range. The winding connection changeover was initially achieved using magnetic contactors and later by power electronic switches. A smooth transition from one winding connection mode to the other can be virtually realized using dual inverter fed motor with open end stator windings by employing the space vector based PWM scheme presented in this paper. The proposed scheme requires only one DC source to produce virtual pentagon, pentacle connections and the PWM technique employed prevents flow of common mode current. The proposed scheme is experimentally validated on a five phase induction motor with open end stator windings using TMS320F28335 DSP as the digital platform for implementing the control scheme.