光伏发电并网系统变步长 MPPT 及电压控制策略仿真研究

摘要

对一个两级式结构光伏发电并网系统进行研究。该系统的前级 Boost 电路采用变步长 MPPT 实现最大功率点跟踪，后级逆变电路通过电压外环、电流内环的双闭环控制方式实现快速电网电压跟踪。利用 MATLAB/Simulink 仿真软件对该系统的变步长最大功率点跟踪方法及并网逆变器的控制策略进行了仿真验证，结果表明所采用的方法及策略是可行的、有效的，满足光伏发电对并网逆变器的要求。%A grid-connected photovoltaic system is studied, which has a two-level circuit structure of the prime boost circuit for MPPT (maximum power point tracking) with variable step algorithm and the inverse circuit for the system voltage control with a voltage loop and a inner current loop. With MATLAB/simulink software, this paper does a simulation on the variable step MPPT and voltage control strategy of the system, showing that the algorithm and control strategy of the system are feasible and effective as to meet the requirements of the photovoltaic grid-connected inverter.