应对移动阴影的车载光伏步进扫描快速功率追踪

移动阴影给车载光伏最大功率跟踪（maximum power point tracking，MPPT）带来巨大挑战. 为提高移动阴影遮挡下的功率追踪速度，提出一种新的车载光伏全局最大功率跟踪（global maximum power point tracking，GMPPT）自适应步进扫描方法. 首先，分析温度及辐照强度对光伏单体输出特性的影响规律，基于温度及短路电流预测光伏单体开路电压；其次，基于串联光伏阵列的最大功率点电压与光伏单体输出特性的关系，以及局部阴影条件下多峰曲线峰值点电压和功率的变化特性，提出功率追踪步进扫描的自适应步长求取方法；最后，通过仿真及样车试验对所提算法进行可行性测试和评估. 结果表明:与常规扫描法相比，本算法的追踪速率最高可提升74%，且可避免严重遮挡时无法追踪全局最大功率点的问题. 

Fast Power Tracking Step-Scanning Method of Vehicle-Mounted Photovoltaic System with Moving Shadows

Moving shadows bring great challenges to maximum power point tracking (MPPT) of vehicle-mounted photovoltaic power generation systems. In order to improve the speed of MPPT under moving shadow occlusion, a new adaptive step-scanning method for global maximum power point tracking (GMPPT) of vehicle photovoltaic is proposed. Firstly, the influence of temperature and radiation intensity on the output characteristics of photovoltaic cells is analyzed, and the open-circuit voltage of photovoltaic cells based on temperature and short-circuit current are calculated; Then, based on the relationship between the maximum power point voltage of the series photovoltaic arrays, the output characteristics of the photovoltaic cells, and the distribution characteristics of the voltage and power at the peak point of the multimodal curve under local shadow conditions, a method of the adaptively adjusting step size for step-scanning MPPT is proposed. Finally, the feasibility test and evaluation of the proposed algorithm are carried out through simulation and photovoltaic prototype vehicle tests. The results show that, compared with the conventional scanning method, the tracking rate of the proposed algorithm can be increased by up to 74%, and the problem that the global maximum power point cannot be tracked in the case of severe occlusion can be avoided.