太阳辐照度与光伏电站发电功率密切相关，其预报的准确性直接影响发电功率预报的准确性。根据光伏电站太阳辐照度实况、气象站实况、WRF（Weather Research and Forecast Model）模式辐照度预报、EC细网格数值预报以及太阳理论辐照度，利用逐步回归法开展太阳辐照度预报订正研究，得到以下结论：①太阳辐照度实况与太阳理论辐照度的比值与EC细网格数值预报中气象要素的相关性优于太阳辐照度实况与气象要素的相关性；②不同时刻影响太阳辐照度的气象因子存在差异，通过逐步回归法建立不同时刻太阳辐照度预报模型；③在非晴天情况下，回归预报辐照度相对均方根误差比WRF模式预报辐照度降低10%左右，减小了辐照度预报误差。该研究成果在光伏电站的新能源数值预报服务中有一定的应用价值。
Solar irradiance is closely related to the power generation of photovoltaic power plants, and the accuracy of irradiance forecast directly affects the accuracy of power generation forecast. Based on the reality of solar irradiance of the photovoltaic power plants and weather stations, WRF model irradiance forecast, the EC fine grid numerical forecast, and theoretical solar irradiance, a study of the revised solar irradiance forecast is carried out by means of stepwise regression. The conclusions are as follows: (1) the correlation between irradiance ratio and meteorological elements is better than that between irradiance and meteorological elements; (2) there are differences in meteorological factors that affect solar irradiance at different times, and a prediction model of solar irradiance at different times is established through the stepwise regression method; (3) in the case of nonclear weather, the RMSE of the regressed prediction irradiance is about 10% lower than that of the WRF model. The results have some application value in the new energy numerical forecasting service for photovoltaic power stations.