Low power battery charger with solar panel input — The M.P.P.T. algorithms

This paper presents a comparative study of three maximum power point tracking (MPPT) algorithms to be used with solar panel input, both from theoretical and practical points of view. An improved perturb & observe (P&O), a sliding mode technique and a method based on power versus voltage variations (dP / dV) are presented. Optimization of the tracking algorithms targets both the tracking of fast changing illumination and the maximum power during constant illumination. All three algorithms have been verified on simulation. Two of them have been tested on a low power hardware platform that connects a low power, low voltage solar panel (20 W, 6 V) with a 12V lead-acid battery. Experimental results measured on two consecutive days with similar weather conditions but different MPPT algorithms are also presented.