Reliability Enhancement of Distribution Substation by Using Network Reconfiguration a Case Study at Debre Berhan Distribution Substation

Most of developing country including Ethiopia distribution systems has received considerably less of the attention to reliability modeling and evaluation than have generating and transmitting systems. Now a day life is directly or indirectly depends on electric power so that utility should deliver reliable power every day for 24 hours and each year for 8760 hours to satisfy human needs and to perform their works as much as possible with less economy. This paper focuses on enhancement of distribution system of Debre Berhan distribution network. The reliability assessment has been done on four feeders of 15kV and 33 kV to assess the performance of the existing system and to predict the reliability analysis for the future. The interruption data of two years 2017-2018 G.C has been used as a base year. Different alternatives have been assessed using heuristic (trial and error) method and the alternative with low SAIDI, SAIFI and EENS with a reasonable cost has been preferred. The reliability of the Debre Berhan distribution system has been enhanced significantly by implementing reliability improvement solutions that are justified economically. Even if the uncertainty of the input data is taken into account, SAIFI has been reduced by 77.33% as compared with the average reliability indices values of the system in the base years. In the similar way SAIDI and EENS have been decreased by 80% and 77.77% respectively.