1. Engineering Research Centre of Motion Control, Ministry of Education, Southeast University Nanjing 210096 China 2. Aichi Institute of Technology Toyota 470-0392 Japan
Abstract：Photovoltaic cells would operation as load when local solar irradiation declines in series connection, which would result in the damages easily. Nowadays modules are often configured with bypass diodes to provide energy releasing route. Furthermore, blocking diode is series connected before parallel connection in order to prevent inverse power injection. Based on such configurations, this paper is mainly devoted to investigate the operation mismatches of the photovoltaic array caused by random shadows, and compared different abilities under diverse series/parallel patterns. Researches indicate that: firstly, traditional monotone algorithms of MPPT could be invalid for detecting false maximum only. Secondly, the “doorsill effect” of local irradiation intensities, namely that global power output might not be influenced by changes of local shadows. Finally, suggestions are put forward that parallel connection should be ranked prior consideration with whole array design, to boost power output relatively.
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2010, Vol. 25 
