MPPT算法在光伏发电系统中的应用研究

摘要

针对传统扰动观察法难以同时兼顾跟踪速度和稳态精度的问题,提出了一种基于改进型变步长扰动观察法的MPPT控制策略;当相邻两时刻功率差大于所设定阀值error时,采用大步长快速定位到最大功率点附近,当相邻两时刻功率差小于所设定阀值error时,采用小步长进行精确定位.通过Simulink仿真平台搭建了基于Boost电路的MPPT仿真模型,Simulink仿真结果表明:改进型变步长扰动观察法不但具有较快的跟踪速度,而且减弱了稳态震荡,避免了能量过多的损失,对提高光伏系统效率有一定积极意义.%Aiming at the problem that the traditional perturbation observation method is difficult to take into account both the tracking speed and the steady state accuracy,an MPPT control strategy based on the adaptive variable step perturbation observation method was proposed.When the power difference is greater than the set threshold error,it uses large step quickly positioning near the maximum power point,when the adjacent two time power difference is less than the set threshold error,it use small steps for precise positioning.The MPPT simulation model based on Boost circuit is buih by Simulink simulation platform.The simulation results of Simulink show that,the improved variable step perturbation observation method not only has a faster tracking speed,but also reduces the steady state oscillation and avoids the loss of energy.It has a certain positive significance to improve the efficiency of photovoltaic systems.