Abstract：The change of positive and negative DC loads of a bipolar DC microgrid will cause the DC bus voltage to deviate from the rated value, causing the positive and negative voltages to be unbalanced, and the unbalanced current generated by it will also increase the network loss. In order to coordinate different distributed power sources to participate in the unbalanced voltage control of the DC microgrid, control the voltage unbalance degree within a reasonable range or a certain limit value, and ensure the stable operation of the system. In this paper, the voltage droop control is used as the primary control, and an unbalanced voltage observer and a voltage unbalance factor controller are established based on the consensus algorithm and the function relationship between voltage unbalance factor and the positive and negative voltage, which as a secondary control to integrate the consensus control of the bus average voltage and the unbalance factor, and the distributed cooperative control of the unbalanced voltage in the bipolar DC microgrid is formed to achieve the convergence of the voltage unbalance factor between poles and the average bus voltage is maintained at the rated value. The stability of the bipolar DC microgrid under the control strategy is analyzed, and the simulation model is built-in MATLAB/Simulink, and the experimental platform is set up to verify the effectiveness of the control strategy.
杨美辉, 周念成, 王强钢, 廖建权, 孟潇潇. 基于分布式协同的双极直流微电网不平衡电压控制策略[J]. 电工技术学报, 2021, 36(3): 634-645.
Yang Meihui, Zhou Niancheng, Wang Qianggang, Liao Jianquan, Meng Xiaoxiao. Unbalanced Voltage Control Strategy of Bipolar DC Microgrid Based on Distributed Cooperation. Transactions of China Electrotechnical Society, 2021, 36(3): 634-645.
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2021, Vol. 36 
