基于阻抗重塑分析的逆变器并网稳定性研究  

Research on Grid-Connected Stability of Inverters Based on Impedance Reshaping Analysis

作　　者：杨茹楠 刘明阳 李德强 徐奕翔 苏旭 YANG Ru-nan;LIU Ming-yang;LI De-qiang;XU Yi-xiang;SU Xu(State Grid Tianjin Electric Power Company Binhai Power Supply Company,Tianjin 300450,China)

机构地区：[1]国网天津市电力公司滨海供电分公司,天津300450

出　　处：《电工电气》2023年第7期14-20,共7页Electrotechnics Electric

摘　　要：在弱电网下,电网阻抗的存在会削弱三相逆变器的稳定裕度,阻抗分析法可针对并网逆变器与弱电网之间的相互作用开展研究。分析了逆变器阻抗重塑控制策略,引入正负序并联校正阻抗进行逆变器的阻抗重塑;通过优化比例前馈系数和改进锁相环结构增大系统的稳定裕度,扩展三相逆变器并网系统稳定运行时电网阻抗范围,提高了系统对弱电网的适应性;将所提控制策略应用于三相逆变器并网系统并通过MATLAB/Simulink进行仿真,结果验证了该控制策略的有效性。The existence of grid impedance weakens the stability margin of three-phase inverters in the weak grids,and the impedance analysis method can be used to analyze the interaction between grid-connected inverters and weak grids.In the paper,the impedance reshap-ing control strategy of inverters is analyzed,and the positive and negative sequence parallel correction impedance is introduced for imped-ance reshaping.The system stability margin increases through optimizing proportional feedforward coefficients and improving phase-locked loop structure,and the system adaptability to the weak grid improves by expanding the grid impedance range as the grid-connected system of three-phase inverters operates stably.The control strategy is applied to the grid-connected system of three-phase inverters and is simulated through MATLAB/Simulink,and the above results verify its effectiveness.

关 键 词：弱电网 并网逆变器 序阻抗 阻抗重塑 稳定性 

分 类 号：TM464[电气工程—电器]