An improved multi-level converter with a novel sub-module circuit

• Published in: IECON 2017 - 43rd Annual Conference of the IEEE Industrial Electronics Society pp. 4863 - 4866
• Main Authors: Xiangfeng Li, Lili Qu, Bo Zhang, Hui Liao, Zonghua Zhang
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.10.2017
• Subjects: Bridge circuits; Integrated circuit modeling; modular multilevel converter (MMC); Modular multilevel converters; Modulation; modulation strategy; sub-module circuit; Switches; Topology
• DOI: 10.1109/IECON.2017.8216839

The modular multilevel converters (MMC) has become an attractive research subject of power electronics due to its special topology. In this paper, a novel sub-module circuit for the MMC is proposed. Compared with the traditional sub-module circuits, the number of power semiconductors used in the proposed circuit is reduced by a quarter. Then, an improved three-phase multilevel topology is also constructed with the proposed sub-module circuit, accordingly, appropriate control logic is designed. The theoretical analysis shows that the line voltage of the proposed multilevel topology is increased from five levels to nine levels, thus suppressed the slew rate of the voltage (dv/dt). The simulation is also conducted in the paper which verified the correctness of the theoretical analysis.