A Comparative Evaluation of the Performance of a novel H9-VSI for Reduced Common Mode Currents

A nine-switch hybrid Voltage Source Inverter (VSI) topology named as the H 9 -VSI has been recently reported in the literature to achieve low common-mode leakage currents while also reducing the converter losses. It uses six Si-IGBTs and three SiC MOSFETs switched with a modified space vector PWM scheme. This paper evaluates the performance of the H9-VSI and compares it with six other recently proposed two-level VSI topologies that are also intended to reduce the common-mode leakage current. Detailed simulation studies are conducted on each topology operating with its own custom PWM technique, at different switching frequencies and modulation indices, and their performance is evaluated in terms of the common-mode voltage, leakage current magnitude, output voltage, line current THD and the converter power losses. Simulation studies are performed in PLECS for each topology for a 10 kW system, and the results are presented to ascertain the merits and demerits of the H 9 inverter compared to other configurations.