A review of maximum power point tracking techniques for use in partially shaded conditions

Partially shaded conditions (PSCs) often occur in large photovoltaic generation systems (PGSs). PSCs cause losses in system output power, hot spot effects, and system safety and reliability problems. When PSC occur, the PGS power–voltage characteristic curve exhibits multiple peak values; that is, the curve comprises a global maximum power point and multiple local maximum power points. Current literature includes various studies of global maximum power point tracking (GMPPT) algorithms and hardware architectures suitable for PSC; because the substantial quantity of PSC literature, this subject must be comprehensively reviewed. To focus on GMPPT techniques used in PSC, traditional maximum power point tracking techniques and circuit architectures that cannot distinguish GMPP and LMPP were not discussed.