基于功率预测的自适应变步长MPPT算法研究

Research on adaptive variable step-size MPPT algorithm based onpower prediction

最大功率点跟踪技术(Maximum Power Point Tracking, MPPT)是光伏发电系统中关键技术研究的热点之一。针对传统扰动观察法跟踪速度和精度无法兼顾的问题,文中提出了一种以功率变化量为步长控制量的自适应变步长扰动观察法,通过判断功率变化趋势,对远离最大功率点,采用大步长逼近;靠近最大功率点,采用小步长逼近。建立太阳能光伏电池数学模型得到其输出特性曲线,再利用MATLAB/Simulink搭建基于Boost电路的MPPT仿真模型,最后经仿真验证了所提出算法的稳定性、快速性和准确性,它比传统算法具有更好的MPPT暂态性能。

Maximum power point tracking(MPPT)is one of the research hotspots in the key technologies of photovoltaic power generation system.In order to solve the problem that the traditional disturbance and observation method cannot give consideration to both the tracking speed and precision,an adaptive variable-step disturbance and observation method is proposed in this paper,which takes power variation as step-size control.By judging the variation trend of power,when it is far away from the MPP,it adopts long step to track;when it is close to MPP,it uses small step to track.Firstly,the mathematical model of solar photovoltaic cell is established and its output characteristic curve is obtained.Then,Matlab/Simulink is used to build the MPPT simulation model based on Boost circuit.Finally,the simulation experiment verifies the stability,rapidity and accuracy of the proposed algorithm,which has better MPPT transient performance than the traditional algorithm.