Novel Switching Strategy for High-Efficiency of Single-Phase Three-level Inverters

This paper proposes a novel switching strategy for high efficiency of a single-phase three-level inverter. Normally, the conventional unipolar and bipolar switching methods are used in the single-phase three-level inverter. In comparison with two conventional switching methods, the proposed switching method, which keeps switching state of some switches for switching period, is advantageous in efficiency. In this paper, an operation principle of the proposed switching strategy is introduced. It is easy to implement because the operation principle is based on the unipolar switching method. Furthermore, in comparison with the unipolar switching method, the efficiency and the current total harmonic distortion of the proposed switching method are shown by simulations results.