Conventional and global maximum power point tracking techniques in photovoltaic applications: A review

Maximum Power Point Tracking (MPPT) is a technique employed to extract maximum power available from a photovoltaic (PV) module under varying atmospheric conditions. It traces the PV operating voltage corresponding to the maximum power point (MPP) and operates the panel at MPP. However, if a PV array is partially shaded, the conventional MPPT techniques track local MPP and fail to track global MPP. Also, if modules with different optimal currents are connected in series—parallel local MPPs occur in the P-V curves and conventional MPPT techniques fail to search global maxima. A lot of literature is available on global MPPT techniques to increase overall system efficiency. The power conditioning unit should, therefore, be capable of searching global maximum power point also. This paper aims at presenting a number of conventional and global MPPT techniques; these methods are discussed in detail on the basis of certain performance parameters.