Design and Modeling of MPPT for Solar Based Power Source

Abstract

Solar energy is freely available, abundant and sustainable in nature throughout the year and other resources are depleting. Solar energy is being converted to various forms such as heat, electricity etc. Solar panel has Photovoltaic (PV) arrays which directly converts light into electricity. The best PV cell has an efficiency of up to 30%. Hence output power is small for input that it takes. Therefore, panel is required to operate at its maximum power point (MPP) to achieve high efficiency. The output characteristics of PV module depends on the solar irradiance, temperature and output voltage of PV module. As the PV cell has nonlinear Current - Voltage (IV) and Power - Voltage (PV) characteristics, it is necessary to design a control circuit or algorithm so that the cell is tuned to operate at MPP irrespective of the load connected and external parameters variations such as illumination and temperature. The panel output characteristics are nonlinear in nature; therefore, it is necessary to model and simulate for use in PV system applications. In order to improve the output efficiency of PV system, a novel variable step size perturbation and observation P&O method is proposed to track the maximum power point of PV system.