三相并网矩阵变换器系统的稳定性分析及其改善

当矩阵变换器用于并网联接系统或者是分频输电系统时,电网对输入谐波要求高,因此矩阵变换器系统的输出端引入T型滤波器取代典型的电感滤波器,并针对T型滤波器带来的不稳定性,提出了基于桥臂输出电流闭环与电压电流双前馈相结合的间接控制策略. 建立该矩阵变换器系统的数学模型,分析传输函数,并对其特征值进行分析,从而研究上述控制策略对系统稳定性的改善作用.

Improvement of the Stability on Grid-Connected Matrix Converter System

When the matrix converter is used in grid connected system or in the frequency division transmission system, the electrical network request few of the input current with harmonic distortion. Therefore, T filter model is introduced instead of a series inductance filter in the matrix converter system out-port, which can achieve reduced levels of harmonic distortion at lower switching frequencies. But it make instability is bring to system by using an T filter. This paper proposes the strategy that integrates an loop bridge current regulator with grid current and voltage feed forward to stabilize the system. The stability of the system is evaluated by building a system model of the whole system, analysing transmission function and the migration of eigenvalues of the system.