针对功率预测算法下光伏最大功率点跟踪(maximum power point tracking,MPPT)系统中存在误判情况的问题,提出一种基于拉格朗日插值法改进功率预测的光伏变步长扰动观察法.首先,通过拉格朗日插值法建立插值模型,以减少预测功率值与实际功率值的偏差;其次,通过对反正切函数归一化的变步长追踪方法改善算法在辐照强度变化及追踪过程中变步长方法引起较大振荡的问题;最后,基于MATLAB/Simulink开展与传统扰动观察法及功率预测算法对比的试验.结果表明:改进功率预测变步长扰动观察法改善误判和失效问题的效果更好.
Abstract
In order to solve the problem of misjudgment in the photovoltaic maximum power point tracking system under the pow-er prediction algorithm,a variable step size disturbance observation method based on Lagrange interpolation method is proposed to improve the power prediction.Firstly,the interpolation model is established by the Lagrange interpolation method to reduce the devi-ation between the predicted power value and the actual power value.Secondly,the variable step size tracking method normalized by the arc tangent function is used to improve the algorithm in the irradiation intensity change and the oscillation caused by the large tracking process.Finally,the simulation model is built on the MATLAB/Simulink platform,and the algorithm is compared with the traditional disturbance observation method and the power prediction algorithm.The results show that the improved power prediction variable step size disturbance observation method has better effect in improving the misjudgment and failure problem.
关键词
光伏发电/最大功率点跟踪/扰动观察法/改进功率预测
Key words
photovoltaic power generation/maximum power point tracking(MPPT)/disturbance observation method/im-proved power prediction
维普
万方数据