Improved quasi-Z-source based three-phase three-level neutral point clamped inverter

In this paper, a new three-phase three-level neutral point clamped (NPC) inverter based on improved Quasi-Z-source (QZS) network is proposed. The proposed QZS inverter in comparison with conventional Z-source and Quasi-Z-source inverters has higher boost factor under smaller duty cycle. Moreover, smaller duty cycle, lower voltage stress, less total harmonic distortion (THD), and continuous input current are some advantages of the proposed inverter. In this paper, different combinations of allowed switching states with their control signals for proposed inverter are presented by using SPWM control method. The simulations results in PSCAD software are performed to prove the performance of the proposed topology.