A novel three-phase multilevel diode-clamped inverter topology with reduced device count

This paper presents a novel configuration of three-phase multilevel diode-clamped inverter (DCI) with reduced part count. In the proposed topology, three-phase multilevel output voltage is generated by employing only two inverter phase legs and the third phase is sharing the unused switches of these two legs depending on the line current flow direction. The structure allows synthesizing multilevel voltage waveform with reduced number of power electronic components: diodes, power semiconductor switches and gate driver circuits compared to classical topologies. Total savings on the power device count increases proportionally for higher output voltage level DCIs. Reducing the counts on the power electronic devices result in decreased complexity and overall system cost for the inverter. The compatibility of developed general space vector modulation (SVM) technique with new multilevel DCI arrangement; make the control scheme simpler and easily implementable. The simulation results confirm the feasibility of the proposed configuration in comparison with the conventional multilevel DCI topology.