A Modified Modular Multilevel Converter With Reduced Capacitor Voltage Fluctuation

作者：Li Binbin^*; Zhang Yi; Wang Gaolin; Sun Wei; Xu Dianguo; Wang Wei

来源：IEEE Transactions on Industrial Electronics, 2015, 62(10): 6108-6119.

DOI：10.1109/TIE.2015.2423665

• Capacitor voltage fluctuation
• medium-voltage drive
• modular multilevel converter (MMC)
• voltage balancing

The requirement of a large number of sizeable capacitors in traditional modular multilevel converter (MMC) submodules is seen as a major barrier hampering its widespread use in medium-voltage applications. To reduce the value of capacitance, this paper presents a modified MMC (M-MMC) topology, which offers inherent alleviated capacitor voltage fluctuations compared with traditional MMC. Its operating principle, modulation, and capacitor voltage balancing strategies are described in detail. Moreover, a novel capacitor voltage fluctuation suppression scheme is also proposed to further reduce the second-order capacitor voltage ripples. Finally, both a three-phase prototype of M-MMC and traditional MMC have been built in the laboratory. The effectiveness of the proposed M-MMC topology and control methods is experimentally verified by comparing with the traditional MMC.

• 出版日期2015-10
• 单位哈尔滨工业大学