基于谐波线性化的三相LCL型并网矩阵变换器正负序阻抗建模分析

Analysis of Positive and Negative Sequence Impedance Modeling of Three-Phase LCL Grid-Connected Matrix Converter Based on Harmonic Linearization

矩阵变换器具有优良的输入输出特性,在各个领域中得到了广泛的应用.为了研究矩阵变换器并网系统稳定性问题,采用谐波线性化阻抗建模法对矩阵变换器并网系统进行小信号建模,得到了具有清晰物理意义的正负序阻抗模型,再使用奈奎斯特稳定判据对系统进行稳定性分析.分析了锁相环参数设计对系统稳定性的影响.为了验证理论分析的正确性,文中在Matlab/Simulink中建立矩阵变换器并网系统仿真模型.仿真结果证明了理论分析的正确性,仿真数据表明合理的锁相环参数设计对矩阵变换器并网系统的稳定性具有重要意义.

Matrix converter has excellent input and output characteristics and has been widely used in various fields. In order to study the stability of the grid-connected system of matrix converter,the harmonic linearization method is used to model the small signal of the grid-connected system of matrix converter,and the positive and negative sequence impedance model with clear physical meaning is obtained. Then the stability of the system is analyzed according to the Nyquist stability criterion. In order to verify the correctness of theoretical analysis, this paper establishes a simulation model of grid-connected system of matrix converter in MATLAB/ Simulink to simulatethe correctness of the positive and negative sequence output impedance,and studies the influence of PLL parameter design on system stability. The simulation data show that reasonable design of PLL parameters is of great significance to the stability of grid-connected system of matrix converter.