Maximum Power Point Tracking of Photovoltaic Generation Based on the Optimal Gradient Method

Photovoltaic (PV) power has been successfully applied for over three decades. PV cell provides power for systems in many applications on earth and space. PV cell exhibits nonlinear voltage-current characteristics and its maximum power point varies with solar illumination and ambient temperature. With the development of power electronics technology, it is now possible to operate photovoltaic system with its maximum power point (NIPP) in order to increase the overall system efficiency. This paper presents a novel algorithm for maximum power point tracking in PV systems based on the optimal gradient method. The algorithm can track maximum power point quickly and accurately. In this paper, the method of optimal gradient for maximum power point tracking (MPPT) is deduced, and the algorithm has been verified based on simulation results in Matlab. The simulation shows the novel algorithm significantly improves the efficiency during the tracking phase compared with a conventional algorithm. The novel algorithm is especially suitable for fast changing environmental conditions. The proposed algorithm can be implemented on any fast controller such as the digital signal processor.