复合比例谐振控制在多逆变器并网系统中的应用

为了消除电网背景谐波对多逆变器并网的影响,采用基波准比例谐振(Quasi Proportional Resonant,QPR)环并联特定谐波补偿环的综合控制策略进行控制.首先建立多台逆变器并网闭环模型,并通过对比传统谐波补偿控制策略和复合比例谐振控制策略的闭环传递函数波特图变化曲线,分析特定谐波补偿器对多逆变器并网时入网电流品质的影响;然后利用Matlab/Simulink软件对所提出的控制策略进行了仿真.仿真和实验结果表明所提出的复合比例谐振控制策略能够更好地对基频处正弦指令信号实行无差跟踪,同时增强对系统在3、5、7次谐波频率处入网电流的抗干扰能力.

Application of Compound Proportional Resonant Control in Multi-Inverter Grid-Connected System

In order to eliminate the influence of background harmonics in grid voltage on the grid connected multiple inverters,an integrated control strategy of quasi proportional resonant (QPR) loop parallelled to the specific harmonic compensation loop is adopted.Firstly,the grid-connected closed-loop model of multiple inverters was established,by comparing the the change curve of the closed-loop transfer function bode diagram of the traditional harmonic compensation control strategy and the composite proportional resonant control strategy,the influence of the specific harmonic compensator on the power quality of the multiple inverters grid-connected was analyzed.Then the proposed control strategy was simulated by using Matlab/Simulink software.The simulation and experimental results show that the proposed compound proportional resonant control strategy can better track the referenced sine signal without any difference,and enhance the anti-interference ability of the gridcurrent at the 3,5 and 7 harmonic frequencies of the system.