Modeling of Photovoltaic Based Grid-Tied System

Abstract

Energy consumption in world is now increasing substantially. Increasing scarcity and rising prices of fossil fuels may lead to economic instability. Continuously increasing in energy consumption will overloads the distribution grids as well as the power stations, therefore imposing a negative impact on power availability, security and quality. One of the solutions for overcoming this is use of renewable energy resources. The energy generation from PV based Grid-Tied System is highly intermittent in nature and shows wide variation because of continuous fluctuations in solar radiation intensity, temperature and unpredictable weather conditions (e.g. clouds, snow, wind, etc.). This poses a major challenge for the designers of grid connected PV systems for its applications. One of the major problems is the increase in the Total Harmonic Distortion (THD) of current injected into the grid. In this paper basic theory of grid connected photovoltaic system and proposes a new scheme for Total Harmonic Distortion (THD) improvement in grid connected Photovoltaic (PV) systems. A hysteresis current control method is introduced in this paper which is providing a PV system with reduced harmonics at the output. This Logic control can be used to improve the THD in grid connected PV systems. The whole system is modeled on MATLAB/SIMULINK. The Simulation results are given to show the overall system performance.