無互連線逆變器并聯系統均流分析

摘要： 理論分析了無互連線逆變器并聯系統中等效輸出阻抗Z∠θ不一致時的功率分布情況。分析表明，Z∠θ呈感性時，Z∠θ不一致會引起無功功率偏差；而Z∠θ呈阻性時，Z∠θ不一致會導致有功功率偏差。在此基礎上提出了下垂系數調整法以減小功率偏差。仿真和實驗結果都表明提出的方法可明顯提高各逆變模塊的功率均分精度。 敘詞：逆變器；并聯；無功功率；有功功率 Abstract：In the parallel inverters without control interconnection,the power distribution is analysed when the equivalent output impendance Z is different between paralleled inverters. Theory analyse indicates that when Z is inductive,the unbalance of Z leads to reactive powers differencewhile Z is resistiveactive power can not be shared because of the unbalance of Z.Based on this analyse,the method called droop coefficient regulation is presented in order to reduce power error. Simulation and experiment prove that the way can improve power-sharing precision markedly. Keyword：Inverter; parallel; reactive power; active power