Harmonic mitigation in distribution network with the presence of pv using unified power quality conditioner

Abstract

The use of photovoltaic (PV) as a source of Distributed Generation (DG) or as a renewable source connected to distribution network are increasing. This type of DG is seen as an alternative future source of energy due to the depletion of conventional sources. Although they could meet the load demand, integration of those sources to the grid since the system itself contains non-linear devices and rapid usage of non-linear loads accelerating the power quality problems. Such problems are sag, dip, swell, harmonics and many more. In this report, harmonics is the key consideration and the Unified Power Quality Controller (UPQC) is proposed to mitigate the harmonics distortions. Shunt APF and Series APF in UPQC is designed in such a manner to and compensate current related and voltage related problems. This project is designed using IEEE 15 bus distribution network, rated 11kV, 60Hz and simulated by using the MATLAB/Simulink Software as a simulation tool with the presence of PV and non-linear loads. First, the harmonic distortion is generated by simulating the nonlinear loads with the Photovoltaic PV system. Then, the analysis of harmonics is carried out using Fast Fourier Transform (FFT) tool to evaluate the Total Harmonic Distortion (THD) level before and after installation of UPQC. The results from analysis showed a clear correlation between the THD % level and impact of harmonics in load flow performance. The THD % level met the IEEE standard and UPQC mitigated voltage harmonics and current harmonics by 10% and 50% respectively. The load flow analysis showed an optimal voltage profile and power efficiency is improved by using UPQC. Generally, this project was completed successfully and significantly contributes to objective.