基于改进MPPT算法的光伏并网系统研究

Study of Photovoltaic Grid-connected System Based on Improved MPPT

光伏并网逆变器是光伏发电系统中重要环节,为使逆变过程中光伏电池输出功率最大,需要对光伏电池的最大功率点进行跟踪。常用最大功率跟踪方法会产生误判现象,不仅会降低光伏电池能量转换效率,而且还会造成并网电流产生畸变。针对上述问题,笔者改进了传统扰动观察法,提出了一种改进型MPPT算法,并在Matlab/Simulink环境下搭建了含有Boost电路的两级式光伏并网逆变器系统。仿真实验表明,含有改进型MPPT的光伏并网逆变器能够有效提高光伏电池输出功率。

photovohaic grid-connected inverter is an important link in photovoltaic power generation system. Photovoltaic cell needs MPPT to reach maximum output power in inverting process. Maximum power tracings generate misjudgments, reducing photovoltaic cell energy conversion efficiency and causing grid-connected current distortion. An improved MPPT is put forward based on traditional perturbation and observation method. Two-stage photovoltaic grid-connected inverter system with Boost circuit is established under Matlab/Simulink conditions. Photovoltaic grid-connected inverter with improved MPPT increases photovohaic cell output power in simulation experiments.