Accurate Power Allocation and Zero Steady-State Error Voltage Control of the Islanding DC Microgird Based on Adaptive Droop Characteristics
Liu Ziwen1, 2, Miao Shihong1, 2, Fan Zhihua1, 2, Chao Kaiyun1, 2, Kang Yilong1, 2
1. State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan 430074 China; 2. Hubei Electric Power Security and High Efficiency Key Laboratory Huazhong University of Science and Technology Wuhan 430074 China
Abstract：The droop-controlled DC microgrid provides an effective means to autonomously integrate the distributed generations (DG), storage units and multi-type loads. However, since the line parameters of each DG are inconsistent and local load exists, the allocation precision of load power is reduced in the conventional droop control. Therefore, it is difficult to maximize the efficiency of the distributed generation, even causing problems such as distributed power overload. Besides, the voltage drop in the lines will furtherly reduce the voltage quality of the DC bus. To realize the appropriate power allocation and eliminate the deviation of DC bus voltage of the islanding DC microgrid under the decentralized control mode, the accurate power allocation strategy and the zero steady-state error voltage control based on adaptive droop control are proposed in this paper. The influence of local load is also considered in the power allocation strategy. Meanwhile, response characteristics analysis of the proposed control of the DC-DC converter is conducted and the influence of key control parameters on system stability is discussed. Simulation results show the validity and efficiency of the proposed control strategies.
刘子文, 苗世洪, 范志华, 晁凯云, 康祎龙. 基于自适应下垂特性的孤立直流微电网功率精确分配与电压无偏差控制策略[J]. 电工技术学报, 2019, 34(4): 795-806.
Liu Ziwen, Miao Shihong, Fan Zhihua, Chao Kaiyun, Kang Yilong. Accurate Power Allocation and Zero Steady-State Error Voltage Control of the Islanding DC Microgird Based on Adaptive Droop Characteristics. Transactions of China Electrotechnical Society, 2019, 34(4): 795-806.
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2019, Vol. 34 
