Simple PWM technique for a three-to-five phase matrix converter

Abstract

Multi-phase converters for more than three-phase applications have become increasingly important topics due to their distinct advantages compared with the conventional three-phase converters. This paper proposes a modified PWM switching technique for direct AC-AC three-to-five phase matrix converter to realize output voltage waveform with low total harmonic distortion (THD) and reduce the total commutation number of its bidirectional power switches in each control period, simultaneously. In order to minimize the switching loss and reduce the voltage stress on all power switches of the matrix converter, the proposed PWM switching pattern prevents any state of direct commutation and switching between the maximum and minimum grid phase voltages. This in-turn enhances the converter durability and lifetime in addition to the power density. Also, the proposed PWM switching technique has the ability to fully control the load voltage waveform and its frequency to meet the reference values. In addition, it has the ability to control the three-phase grid currents to be sinusoidal waveforms and in-phase with grid voltages for unity power factor. Moreover, it enables voltage transfer ratio of 78.86% of the source input voltage. A laboratory prototype has been carried out in order to investigate the effectiveness of the proposed switching technique.