Theoretical and experimental analyses of photovoltaic systems with voltage- and current-based maximum power-point tracking

Detailed theoretical and experimental analyses are presented for the comparison of two simple, fast and reliable maximum power-point tracking (MPPT) techniques for photovoltaic (PV) systems: the voltage-based (VMPPT) and the current-based (CNIPPT) approaches. A microprocessor-controlled tracker capable of online voltage and current measurements and programmed with VMPPT and CMPPT algorithms is constructed. The load of the solar system is either a water pump or resistance. "Simulink" facilities are used for simulation and modeling of the novel trackers. The main advantage of this new MPPT, compared with present trackers, is the elimination of reference (dummy) cells which results in a more efficient, less expensive, and more reliable PV system.