A Novel Space Vector Modulation Strategy for Three-Level Simplified Neutral Point Clamped Inverter

To improve efficiency of the three-level (3-L) simplified neutral point clamped (SNPC) inverter, a novel space vector modulation (SVM) strategy is proposed in this paper. The proposed SVM strategy is characterized by switching all switches in 2-L inverter stage only under zero voltage, thus achieving zero voltage switching (ZVS). Therefore, the switching loss of 2-L inverter stage can be diminished. 3-L SNPC inverter suffers from unbalanced neutral-point voltage (NPV) as conventional multilevel inverters. By using alternative small vectors, the NPV can be balanced as well. The performance of the proposed SVM strategy is analyzed in terms of switching loss and the ability of NPV control. Finally, the feasibility and superiority of the proposed strategy are verified by simulation and experiment.