Industrial Electric Power Supply Reliability, Power Quality Problems and Mitigation Techniques

Abstract

This paper is concerned about power supply reliability and quality analysis work done at Zuqualla steel rolling Mill Enterprise. The factory is found in Debre Zeit town 45km east direction from the Ethiopian capital Addis Ababa. The analysis focused mainly on the evaluation of power supply reliability and power quality in the factory premises and at the distribution substation and thereby proposing recommendations to the supply authority and factory for better improvement. The methodologies followed for the investigation and analysis are direct measurement at the substation supply transformers and by using data gathered from the substation and factory loads. This particular analysis work indicated that the fifth and seventh spectral harmonic components have a major effect in the supply system of the factory with 25% and 20% harmonic distortion level respectively. The factory has been working with poor power factor of 0.75 which is below the minimum threshold standard of 0.85 which is set by the Ethiopian Electric Utility (EEU). Finally, MATLAB/SIMULINK model of shunt harmonic filters were designed. By this, the fifth and seventh harmonic components are reduced to less than 5% and average power factor upgraded to 0.93.