基于重复和PI复合控制的光伏并网逆变器研究

Research on Photovoltaic Grid-Connected Inverter Based on Repetitive and PI Control

并网逆变器的控制策略是光伏逆变器各个控制模块中最重要的环节,如何使得逆变器输出电流很好地跟踪电网电压,实现同频同相,输出波形质量更高是逆变器控制的关键。针对以上问题,对重复控制原理进行了深入的分析,设计PI闭环控制、重复控制以及重复和PI复合控制这3种控制方法对周期性扰动进行调节,并在MATLAB/Simulink环境中进行了仿真,取得良好的并网逆变控制效果。仿真结果充分地说明了重复和PI复合控制对周期性扰动有更好的抑制作用。

Grid-connected inverter control strategy is the most important link in the photovohaic inverter control module, and how to make the output current of the inverter to track the grid voltage to achieve the same frequency and the same phase and improve the quality of the output waveform is the key of the inverter control. To solve the problem, deep analysis of Repetitive control principle is made, and three control methods which are PIelosed-loop control, repetitive control and repeat and PIcomposite control are designed to adjust the periodic disturbance. And simulation in MATLAB/Simulink environment is made. It achieves good grid inverter control effect. The simulation fully results that repeat and PIcomposite control has better inhibition to the periodic disturbance.