The power-voltage characteristic curve of solar PV modules has a multiple local maximum under partial shading conditions; in this case the conventional MPPT methods fail to track the real maximum power point which reduces the efficiency of the photovoltaic system. To keep the PV modules operate with their maximum power, this paper places a novel algorithm which is able to detect and track the global maximum under different shading conditions. The performance of the proposed method is verified by simulation and compared to the conventional perturbation and observation (P&O) method.