Analysis of Photovoltaic System using Particle Swarm Optimization Method to Reduce THD

The PV system exhibits a nonlinear power-voltage characteristic, its maximum power point (MPP) varies with irradiance and temperature. Under various conditions, it is possible to have multiple local maxima in some cases, but overall there is only one true MPP. This not only affects the power output of the PV systems, but also leads to complexity and reliability problems. Traditional methods are difficult to find the true MPP fast and accurately. Particle swarm optimization (PSO) is more suitable to reduce the steady state oscillations present in the current and voltage waveform at the output of the inverter. A modified soft computing technique called particle swarm optimization algorithm (PSO) is used to improve the switching of the inverter. This PSO based control algorithm along with PI controller is developed in MATLAB, which generates an error voltage and it is analysed using PSO based controller in order to improve the switching. In this paper PV system is analysed without using PSO as well as using PSO. It is concluded that while using PSO, improved current and voltage waveforms are observed which are responsible to reduce steady state oscillations in the system. FFT analysis is also done which shows that Total Harmonic Distortion (IEEE Std.519) due to the use of PSO based controller are within the acceptable limits defined by IEEE standards. It improves the reliability of the system.