Abstract：In order to overcome the problems of traditional AC microgrid, such as the high output voltage harmonic content,the serious harmonic pollution of power grids and so on. a new structure of microgrid based on modular multilevel converter (MMC) is proposed, in which the generation module composed of micro-source, converter and energy storage device is connected to the DC side of MMC sub-module to form a three-phase inverter system, and then the filters, protective devices and loads is connected to its AC buses to form the microgrid. The mathematical model of system output voltage is established based on the islanded equivalent circuit, and the output characteristics of the system are analyzed in detail. The corresponding solutions to the problems of output voltage fluctuation, energy dispatch and micro-source output power coordination are put forward and the system model is built in Simulink. The simulation and experimental results prove the correctness of theoretical derivation and analysis, and verify the feasibility and effectiveness of the micro-grid topology.
王兴贵, 薛晟, 李晓英. 模块化多电平变流器半桥串联结构微电网输出特性分析[J]. 电工技术学报, 2019, 34(10): 2130-2140.
Wang Xinggui, Xue Sheng, Li Xiaoying. Analysis of Output Characteristics of a Microgrid Based on Modular Multilevel Converter Half-Bridge Series Structure. Transactions of China Electrotechnical Society, 2019, 34(10): 2130-2140.
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2019, Vol. 34 
