Abstract:The principle of double closed-loop control strategy,which is based on the hysteresis- band current tracking control,can connect modular multilevel converter(MMC) with power grid. By real-time monitoring the voltage of the grid and the deviation between the output current and the given current, the output voltage is determined, and therefore the output current can track the given current quickly and efficiently. Switching frequency and the ripple frequency of grid current are analyzed in detail to prove the superiority of the strategy. Finally, the virtual submodule(VSM) is built,and by changing the loop mapping relationships between the VSMs and the real submodules, which is based on comparing the voltages of submodules and the direction of current in one arm, the voltages of the upper/lower arm’s capacitors can be well balanced. The proposed method can be used for any number of submodules and any levels. The validity of the proposed method is verified by experimental results of five-level prototype of MMC.
吉宇,梅军,杜晓舟,韩少华,郑建勇. 基于模块化多电平变换器的电流滞环跟踪型并网控制策略[J]. 电工技术学报, 2015, 30(4): 26-34.
Ji Yu,Mei Jun,Du Xiaozhou,Han Shaohua,Zheng Jianyong. Hysteresis-Band Current Tracking Control Strategy to Connect Modular Multilevel Converter with Power Grid. Transactions of China Electrotechnical Society, 2015, 30(4): 26-34.
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