Efficient MPPT control for fast irradiation changes and partial shading conditions on PV systems

Power output from the PV arrays are directly proportional to the sun's radiation occurring on its surface area. Partial shading on the PV arrays reduces the power output and produces multiple peaks on the P-V characteristics. The power losses caused by partial shading depend on its pattern and array configuration but does not depend on the shaded area. A Maximum Power Point Tracking (MPPT) method is proposed in this paper to detect the occurrence of shading on PV arrays and finding the Global Maximum Power Point (GMPP) with minimum tracking time. The MPPT controller detects the occurrence of partial shading without periodic scanning. The efficiency of the proposed MPPT method is compared with Perturb and Observe (P&O) and Incremental Conductance (INC) MPPT methods. The results proves that the proposed MPPT method identifies the occurrence of shading on the PV array and tracks the GMPP within a short time and thus proving efficient over the two methods.