MODELLING AND EVALUATION OF THE PROTECTIVE SYSTEM

Abstract

this research, modeling and evaluation of the protective system of Omu Aran/Otun 33 kV feeder network is considered and a search for the protective system improvement is obtained. System data of the feeder network were obtained to create the feeder network’s load flow analysis and short circuit analysis using Electrical Network Modeling and Simulation software tool called Electrical Transient Analyzer Program (ETAP). The software creates an electrical digital twin and analyzes electrical power system dynamics, transients and protection. In Nigeria, power supply availability, sufficiency and reliability are major operational challenges. In power system, sometimes faults occur and affect system reliability. Proper evaluation of the operations of the protective system is important to identification of design deficiency, component failure and incorrect settings which will improve the reliability of the feeder network. A short circuit analysis was performed in addition to the load flow analysis which tells the possible fault currents in the system. The three-phase, lineground (LG), line-line (LL) and line-line-ground (LLG) fault currents for a fault on each bus respectively. The load flow analysis was carried out to identify the conditions of the network while the short circuit analysis was carried out to determine the faults currents associated with the network. The load flow results: percentage voltage profile obtained from the load flow result shows that the voltage values at the buses fall within the permissible limit with the highest and lowest voltages of 100.06V and 98.07V respectively. Also, the percentage loading results as show that the Aaye Transformer is critical with percentage loading of 298.7%. The percentage voltage profile of the network under fault shows that the network cannot regain its stability under fault conditions. The network experience a worst and best voltage dip of 30.2% and 11.7% at Ilogbo and Imode Ekiti respectively.