An Investigation on Factories Power Quality (Harmonic) Problems So That to Protect Equipment’s Damaging at the Distribution Network (Case Study: Maa-Garment, Mekelle, Ethiopia)

Abstract

In modern electric power distribution systems especially at industrial distribution, there is a sharp rise in the use of non-linear loads due to high growth in industrial loads. These non-linear loads generally have solid state control of electric power and draw a non-sinusoidal unbalanced current from AC mains which resulting in harmonics injection, reactive power burden, excessive neutral currents and unbalanced loading of AC mains. In this project the industries in Mekelle city named as MAA-Garment power quality (harmonic) problem was investigated and remedies has been givenby designing filters based onitspower quality problems.  So far, a number of attempts have been made on the analysis, design and development of equipment generally named as active power filter (APF) to provide a dynamic and adjustable solution to eliminate harmonics and reactive power burden on the AC mains. The work entitled here concentrated on the new control scheme of series inductive filters. The dominating sources of distortion, at MAA-Garment industry are motors, converters, power factor correction capacitor& other electronic devices plus machines. The presence of that non-linear equipment in factory yields an increasing of harmonic current on Management distribution system which leads to degradation of system performance of machines. Therefore, the mitigation technique to overcome this problem was accomplished by designing series inductive filter at branches of non-linear loads and the total harmonic order was reduced from 7^th to less than 5^th order at the respective nodes.  .

Keywords: Power system harmonic, Mekelle City