基于S-V特性分析的晶硅光伏组件阴影遮挡故障诊断

PARTIAL SHADOW FAULT DIAGNOSIS OF CRYSTALLINE SILICON PHOTOVOLTAIC MODULE BASED ON S-V CHARACTERISTIC ANALYSIS

针对广泛使用的晶硅光伏组件,通过Simulink建立太阳电池双二极管精确仿真模型,对实际应用中最常见的光伏组件阴影遮挡故障进行多种工况的仿真验证。根据I-V曲线拐点、台阶、曲线下积分面积(S)下降的特征,提出一种基于S-V曲线特性的光伏组件阴影遮挡故障的在线诊断方法。该方法建立S-V曲线,根据S-V曲线分叉点位置可判断光伏组件遮挡情况,通过整体积分面积进而判断遮挡比例。对温度、辐照度进行折算,使该方法在全工况下适用。结合光伏组件功率优化器验证该诊断方法有较高的准确率,并且可准确地判断阴影遮挡面积,具有很高的实际应用价值。

For the widely used crystalline silicon photovoltaic(PV)modules,an accurate simulation model with double diodes of the solar cells is established on Simulink. The most common partial shading faults of PV modules in practical applications are simulated and verified under various working conditions. According to the characteristics of the inflection point,step and the integral area(S)based on the I-V curve,an online partial shading faults diagnosis method of PV modules using the characteristic of S-V curve is proposed. This method establishes the S-V curve of the PV module first,and judges the shading modes of PV modules according to the bifurcation point position of the S-V curve,and further judges the shading ratio by the overall integral area. The temperature and irradiance are normalized to make the method applicable for all working conditions. Combined with the PV module power optimizer,it is verified that the proposed diagnosis method has a high accuracy rate and can accurately estimate the shading area of each PV module.