A Nine-Level T-Type Packed U-Cell Inverter

Abstract

This letter proposes a novel nine-level T-type packed U-cell inverter, which consists of one T-type neutral point clamped leg, one half-bridge, two switches, and two identical dc sources. The single-carrier modulation scheme can easily produce the corresponding switching sequences, which makes the T-type leg switching under high frequency and other switches operating under low frequency. To further improve the operational efficiency, the T-type leg can be constructed by using silicon carbide (SiC) devices for withstanding the necessary high-frequency switching. The experimental results verified the performance of the proposed topology.