A generalized switching function-based discontinuous space vector modulation technique for unbalanced two-phase three-leg inverters

Abstract

This paper presents a discontinuous space vector modulation technique for unbalanced two-phase three-leg inverters. This technique is based on the shift-angle and generalized modulation algorithm obtained for generating the unbalanced two-phase output voltage. Furthermore, the discontinuous switching sequence intends to improve the commutations of power switching devices in each inverter leg that achieves a minimum number of switching state changes in one sampling cycle. Therefore, the switch commutations can be reduced by one-third in one main period. The step-by-step procedure of the modulation algorithm for easy implementation in a digital control platform is discussed. The performance of the developed modulation technique is verified through both simulation and experimental results in a nonunity power factor balanced two-phase load and asymmetrical two-phase induction motor drive.