Abstract:Based on the analysis of parallel-connected inverters in low-voltage microgrid, a voltage controller based on virtual complex impedance is developed by introducing virtual complex impedance, so that the output impedance of inverters can be resistive under the conditions of mains frequency and it can improve the performance of parallel multiple-inverters. The effects of different control parameters on the output impedance are discussed through the amplitude-frequency characteristic analysis of output impedance, and appropriate control parameters are selected and the corresponding droop control method is given. Finally, the simulation model and experimental platform are built. Simulation and experiment results verify that the proposed method is correct and effective.
张庆海, 罗安, 陈燕东, 彭楚武, 彭自强. 并联逆变器输出阻抗分析及电压控制策略[J]. 电工技术学报, 2014, 29(6): 98-105.
Zhang Qinghai , Luo An , Chen Yandong , Peng Chuwu , Peng Ziqiang. Analysis of Output Impedance for Parallel Inverters and Voltage Control Strategy. Transactions of China Electrotechnical Society, 2014, 29(6): 98-105.
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