Abstract：Frequency and voltage droop control is a general power control and load sharing strategy in islanded microgrids. However, when all distributed generation (DG) units are connected to the microgrid via power-electronic converters, it is difficult to reflect the power imbalance via the frequency deviation in microgrid. And the conventional droop control based on power-frequency relationship will not be functioning. This paper reveals that the PCC bus voltage magnitude (V) and the ratio (rat) of d-axis bus voltage to q-axis bus voltage are related to power imbalance in a power-electronic converter interfaced microgrid. A P-V and Q-rat droop control method is proposed. With this control, the islanded microgrid can maintain stable voltage and frequency, and all DG units can accurately share active and reactive loads according to preset ratios. Simulation results on an islanded microgrid in its steady-state and load-switching operation verify the proposed method.
吴翔宇, 沈沉, 赵敏, 李凡, 马红伟, 吕斌. 基于公共母线电压的微电网孤网运行下垂控制策略[J]. 电工技术学报, 2015, 30(24): 135-141.
Wu Xiangyu, Shen Chen, Zhao Min, Li Fan, Ma Hongwei, L18-2014-0521/img_1.wmf9.012.0Bin. A Droop Control Method Based on PCC Bus Voltage in Islanded Microgrid. Transactions of China Electrotechnical Society, 2015, 30(24): 135-141.
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2015, Vol. 30 
