改进自适应变步长光伏系统最大功率跟踪

为提高对太阳能的利用率,减少能量的损失,需要对光伏电池的输出进行最大功率跟踪。文章建立了通用的太阳能电池数学模型,结合太阳能电池的功率电压和电流电压输出曲线特性及两者之间的数学关系,提出了一种基于Boost电路的变步长电导增量法。该方法能根据外界环境的变化,简单快速计算出此刻外界环境下唯一一个特殊点的值作为自适应变步长,比传统的变步长或者固定步长方法更合理,同时减少了参数确定的人为因素对于仿真结果的影响,可以快速精确地实现最大功率跟踪。

Modified Adaptive Variable Step of Maximum Power Point Tracking for Photovoltaic System

In order to improve the utilization of solar energy and reduce energy loss, the maximum power point tracking (MPPT) is required to adjust the output of PV cells. Firstly, the mathematical model of solar cell is built in this paper. Then a variable step incremental conductance method based on Boost circuit is proposed by considering output characteristic of power versus voltage and current versus voltage for the solar cell and their mathematical relationships. Furthermore, the only one special point value can be calculated simply and rapidly according to the change of external environment, and the special point value is used as adaptive variable step size, which is more reasonable than that of traditional fixed step or variable step size method. In addition, the influence of artificial factors on simulation results is reduced, and the MPPT can be achieved quickly and accurately.