基于下垂控制模式的独立微电网小干扰稳定分析

Small Disturbance Stability Analysis of Independent Microgrid in Droop Control Mode

从电力系统的运行原理出发,开展独立微电网系统运行稳定性研究对于促进分布式发电技术的发展具有重要意义。针对独立微电网系统运行稳定性问题,以李雅普若夫判据和特征值分析法为基础,对基于下垂控制模式的独立微电网系统的小扰动问题展开分析。首先,构建基于下垂控制模式的独立微电网系统数学建模,并基于线性化理论进行小扰动线性化分析,得到系统小扰动线性化状态矩阵;其次,基于李雅普若夫判据理论,对系统小扰动线性化状态矩阵的特征值进行分析,并逐一改变系统各个参数取值范围得到状态矩阵特征值变化的根轨迹;最后,基于状态矩阵特征值变化根轨迹确定系统各参数初步优化结果,并对比各参数优化前后的系统状态矩阵特征值分布情况,理论分析及实验验证表明初步优化后的系统运行可靠性增强。该研究成果可为微电网控制参数的优化选取提供思路和方法。

Starting from the principle of power system operation,the study of the operation stability of independent microgrid system is of significance to promoting its stable operation.Aimed at the operation stability of independent microgrid system,its small disturbance problem in droop control mode is analyzed on the basis of the Lyapunov criterion and eigenvalue analysis method.First,the mathematical model of independent microgrid system in droop control mode is constructed,and small disturbance linearization analysis is performed based on the linearization theory,thus obtaining the system’s small disturbance linearization state matrix.Second,based on the Lyapunov criterion theory,the eigenvalues of this matrix are analyzed,and the root locus of these eigenvalues is obtained by changing the range of system parameters one by one.Finally,based on the eigenvalue root locus of the state matrix,the preliminary optimization results of system parameters are determined,and the eigenvalue distributions of the system state matrix before and after optimization are compared.The theoretical analysis and experimental verification show that the reliability of system operation after the preliminary optimization is enhanced.The research results of this paper can provide ideas and methods for the optimal selection of microgrid control parameters.