Analog Control Algorithm for Maximum Power Trackers Employed in Photovoltaic Applications

Abstract

Tracking the Maximum Power Point (MPP) of a photovoltaic (PV) array is usually an essential part of a PV system. The problem addressed by Maximum Power Point Tracking (MPPT) techniques is to find the voltage <TEX>$V_{MPP}$</TEX> or current <TEX>$I_{MPP}$</TEX> at which a PV array should operate to generate the maximum power output <TEX>$P_{MPP}$</TEX> under a given temperature and irradiance. MPPT control methods such as the perturb and observe method and the incremental conductance method require a microprocessor or DSP to determine if the duty cycle should be increased or not. This paper proposes a simple and fast analog MPPT method. The proposed control scheme tracks the MPP very quickly and its hardware implementation is simple when compared with the conventional techniques. The new algorithm can successfully track the MPP even in the case of rapidly changing atmospheric conditions. In addition, it has higher efficiency than ordinary algorithms.