Abstract：Droop control strategy is widely applied in AC microgrid to realize the seamless transition between grid-connected (GC) mode and islanding (IS) mode, and to achieve average power sharing among different inverters. However, there is a lack of analysis about the operation of droop control strategy in GC mode. Actually, the power flow control in GC mode may be influenced by the fluctuation of grid frequency and voltage magnitude. Moreover, tracking error also exists in the reactive power control loop. The feedforward of grid frequency and voltage magnitude is proposed to suppress the grid fluctuation impacts in this paper. The voltage magnitude control of PCC voltage is added to realize the precise reactive power control. With the implementation of the proposed control scheme, accurate power flow control is guaranteed for droop-controlled inverters in GC mode.
陶勇, 邓焰, 陈桂鹏, 何湘宁. 下垂控制逆变器中并网功率控制策略[J]. 电工技术学报, 2016, 31(22): 115-124.
Tao Yong, Deng Yan, Chen Guipeng, He Xiangning. Power Flow Control Strategy for Droop-Controlled Inverters. Transactions of China Electrotechnical Society, 2016, 31(22): 115-124.
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