Research on control method of T-type three-level topology

Abstract

A T-type three-level inverter topology is studied in this paper, and a control method based on the topology is presented. For T-type topology, according to the polarity of the load current, the method take a correspondingly control to the switch state of zero level to output the reference voltage, which reduce the switch loss. To solve the problem of neutral-point potential balance, neutral-point charge adjustment algorithm is introduced, which effectively suppress neutral point voltage drift. Finally, T-type three-level model is built under environment of MATLAB and the results of simulation verify the feasibility and effectiveness of the control method.