Mitigation of Harmonics in Power Transmission Network using Filters

Abstract

In the novel times, with the surge in use of power electronics, power quality with system efficiency is playing a symbolic role for the advancement of electric supply. The fundamental purpose of the electric utility is to provide a sinusoidal voltage at constant magnitude throughout the system. This objective is convoluted because of the loads present in the system which produce harmonic currents. Due to these harmonic currents, distorted voltages and currents are carried out which affect the reliability and efficiency of the system in several ways. The sinusoidal waveform produced by electric utilities is distorted due to harmonics and increased use of non-linear loads. The deterioration of the power quality and reliability of the power system is due to the presence of these harmonics in the power system. Hence, we need a proper analytical approach to study, classify and characterize the harmonics present in the system and develop a suitable and effective mitigation method to reduce the harmonics in the power system to standard limits of harmonics prescribed by the IEEE and IEC standards. The study of the level of harmonics present in the system, their causes and effects are known as harmonic analysis or harmonics study. Based on the observations of harmonic analysis we develop mitigation techniques to reduce these harmonics. One such method is the implementation of filters. By implementing harmonic filters, we mitigate the harmonics present in the system by providing a low impedance path. The methodological procedure behind effective design and implementation of filters is achieved by performing load flow analysis to obtain the system data and harmonic analysis to obtain data of harmonics present in the system. Based on the data obtained, the type of filter and the optimal placement of filter is decided to mitigate the harmonics. The mitigation of harmonics can report significant benefits for industries, data centers, etc. in terms of overall installation cost and protection against interruptions and equipment faults in the power system. The overall process of Harmonic analysis and mitigation techniques are performed using Mi-Power software.