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Electric energy is essential for real world. Electric power system is the integration of generation, transmission and distribution stations. It is a network of electrical components deployed to supply, transfer, and use of electrical power. In order to use the utmost benefit from the entire electrical power system, a proper electric power quality should be maintained. There are several PQ problems that can significantly affect the performance of electric equipment in the industries and affect the day-to-day activities of individual consumers. Hence, industries should give high priority for mitigation measures in case PQ problems occur by various factors. The present study was carried out with the main objective to assess the PQ problems of industrial enterprises and evaluate the PQ problem mitigation techniques taking APPF as a case. The data collected were analyzed based on acceptable values set by IEEE 519-1992 standard that is suitable for developing mitigation power quality problem models. Modeling was done using DVR and SAPF models. MATLAB software was employed to analyze the data and run the models. The Simulation of factory power distribution system with and without PQ problem mitigation techniques were carried out using MATLAB/SIMULINK. Result analysis was also done by comparisons of factory power distribution system with and without mitigation techniques, which considered cost and IEEE standard. Moreover, the PQ problems were evaluated based on IEEE standard. Results reveal that the three phases to ground fault is occurred at distribution line and the voltage sage occurred around 65.78% rms, which was unacceptable voltage according to the IEEE standard. But when DVR is connected, injected missing voltage around 34% rms, the voltage variation is solved and acceptable by IEEE standard. Results also show that the THD of the factory is 11.52% indicating it is beyond the IEEE standard (i.e. 5%). However, when SAPF is connected, the THD reduced from 11.52% to 0.21% implying it fits the acceptable IEEE standard. The simulation result of this thesis depicts that DVR provides better response to protect voltage sage problem occurs on sensitive loads. The cost and recompense period of DVR results confirm that DVR has relatively low cost, small in size and fast dynamic response time. Based on the results found of this thesis, it is recommended that the factory should consider using both the DVR and SAPF effective PQ mitigation techniques. |
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