Investigation and Mitigation of Power Quality Problems (Case Study: ETUR Textile Factory)

Abstract

This thesis presents assessment of power quality problems of ETUR Textile factory which is located in Ethiopia, Oromia Regional State at Adama town about 6km from the town towards south on the road to Wonji city. The assessment investigates the major electrical phenomena that disturb the power quality of this particular factory. Because textile industries have high technology machines including electronic control cards and driver controlled motors, poor power quality may damage the system and cause production failure. Many studies showed that the losses caused by electric quality problem in textile industries took at least 2hr to restore at full capacity operation due to these the company loss hug money. In this occasion some of power quality problems have been discussed based on the behavior of the company; it has dedicated line directly from Wonji substation which is around 3km. So the thesis mainly focuses on harmonics and power factor correction rather than other power quality problem. The necessary data are collected from the factory through direct measurement using harmonic analyzer The collected data are analyzed and the results are then compared with the IEEE standards to identify the type and level of the power quality problems The analysis of the harmonic distortion has indicated that the worst individual harmonic distortion of 34.4 % 5th&7th harmonic components have been existing in the power distribution system of the factory. Again, it has been observed that the factory has been working with poor power factor which is 0.814. Consequently, shunt harmonic filters that have an added feature of power factor correction are designed to reduce the amount of current harmonics and for upgrading power factor. With the designed shunt harmonic filters the dominant current harmonic components 5th&7th are reduced to 0.15% and average power factor has been upgraded to 0.96. The modeled systems with and without shunt harmonic filter have been simulated using MatLab /Simulink software to verify the improvements achieved in terms of power quality. The result showed significant improvements. It is concluded that the problems like harmonic distortion; poor power factor has been discussed.