Transient Control Strategy of Droop-Controlled Inverter Considering Fault Current Limitation
Ge Pingjuan1, Xiao Fan1, Tu Chunming1, Chen Leqi1, Zhou Da2
1. National Electric Power Conversion and Control Engineering Technology Research CenterHunan University Changsha 410082 China; 2. State Grid Jiangsu Electric Power Co. Ltd Nanjing 210019 China
Abstract：The droop-controlled inverter can provide voltage and frequency support for the power grid, and its transient stability is important. However, the stability of power angle and fault current affects the safe operation of the droop-controlled inverter under fault conditions. In this paper, the transient characteristics of the droop-controlled inverter are analyzed, and the influence of current limiter and Q-U loop on the transient characteristics of the inverter is described in detail. Accordingly, this paper proposes a transient control method for the droop-controlled inverter which takes into account both fault current limitation and power angle stability. The proposed method considers the variation of the grid voltage and the output voltage of the inverter during the fault period and realizes the power angle stability of the inverter by adjusting the active power reference. In addition, the fault current can be effectively suppressed by the optimal control of the Q-U control loop. Finally, the effectiveness of the proposed method is verified by simulation and experiment.
葛平娟, 肖凡, 涂春鸣, 陈乐祺, 周达. 考虑故障限流的下垂控制型逆变器暂态控制策略[J]. 电工技术学报, 2022, 37(14): 3676-3687.
Ge Pingjuan, Xiao Fan, Tu Chunming, Chen Leqi, Zhou Da. Transient Control Strategy of Droop-Controlled Inverter Considering Fault Current Limitation. Transactions of China Electrotechnical Society, 2022, 37(14): 3676-3687.
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