The study on hot spots failure of polycrystalline wafer based photovoltaic modules

This work studies hot spot failure in photovoltaic modules caused by high reverse-current leakage of solar cells and modules due to an internal arcing effect. Based on theory and demonstrated under experimental testing of modules with high leakage current cells, a positive correlation was found under shading conditions between the temperature of the shaded area and reverse leakage current. Through continued analysis, simulation, and experiments on modules showing hot spot failure in photovoltaic power plants, it is also discovered that even in the absence of shading, thermal stresses caused by variances in day-night temperature in combination with poor soldering connections may form small gaps and cause an arcing effect, which can lead to severe hot spot failure.