MODELING AND SIMULATION OF GRID INTERFACED PV SYSTEM

Abstract

The concern of environment due to green house gases and global warming have forced grid designers to design a smarter power system that has potential to integrate renewable energy sources with the power grid. Solar and wind power generators, now, have become standard electrical energy sources. In contrast to fossil fuels, which are quickly being drained, renewable energy sources are regularly recharged and environmental friendly. The human activities contribute to the global warming of the planet. Today depleting fossil fuels is not the only concern, but also its rising prices which are affecting the economic stability worldwide. The photovoltaic (PV) generation system is one of the best renewable energy sources available to meet out the energy crisis. It is safe, clean, pollution-free, and it requires less maintenance and inexhaustible. Solar photovoltaic system may be implemented as standalone system or grid connected system. In recent years, the power generation through solar PV systems have shown rapid growth all over the world .There has been a remarkable increase in the grid interfaced PV systems being connected to the distribution end. These systems require high quality, low harmonic distortion and current injection into the grid. Inorder to fulfill these objectives, careful consideration of the inverter control is required. In this work, modeling and simulation of grid interfaced 8 kW solar photovoltaic system is presented under different load and atmospheric conditions. The MPPT algorithms for tracking maximum power are presented. The inverter control for integrating the PV system to the grid is presented. The three phase inverter works as a multi-tasking device, which not just supplys power to the grid as power converter but also behaves as harmonic eliminator. The inverter controlling operation is performed on the system using three different control algorithms, under different load and environmental conditions in MATLAB/SIMULINK. These inverter control schemes are implemented to have reduced harmonics in the source current occuring due to various loads in the system. The system further involves the implementation of LCL filter between the PV array and distribution grid, providing reduced THD.Hence, the system have better power quality with reduced THD.