Analysis of Photovoltaic Array Performance under shaded conditions

The generating power of PV arrays or cells would be reduced by mismatch losses, mainly in the case of shadows. Modules are often configured with bypass diodes to provide energy releasing route. And blocking diode is series connected before parallel connection in order to prevent inverse power injection. Based on such configurations, the paper was mainly devoted to investigate the performance comparison between diverse series/parallel PV array patterns when mismatch existed. Corresponding results demonstrated three aspects: firstly, bypass and blocking diode had great effect in reducing the mismatch power when the cell was in shadow; secondly, suggestions were put forward that parallel connection should be ranked prior consideration with whole array design, to boost power output relatively; finally, the "doorsill effect" of local irradiation intensities, namely that global power output might not be influenced by changes of local shadows.