Power Reliability Assessment Of Adama Power Distribution System

Abstract

The objectives of this thesis work are assessing reliability of Adama distribution systems and proposed potential solution to enhance reliability of the system. This thesis starts with collecting important data for reliability assessment in Adama distribution system. Based on this data, reliability indices of the distribution system have been calculated and evaluated. This thesis work compares the three-distribution system of Adama city, namely the old distribution system, upgraded distribution system and rehabilitant distribution system. Based on this analysis, gaps have been identified and major improvement options have been developed. The two well-known customer oriented average system reliability indices have been evaluated for the year 2015 to 2017of old distribution system. The average annual SAIFI and SAIDI values of this system are 314.43 fr/customer/year and 325.24 hr/customer/year respectively. As a result of this long-time outage the power utility has lost on the average 8.075 Billion birrs/year. The upgraded Adama distribution system with the rating of 100MVA has been evaluated for its reliability for six months starting from January to June 2018. SAIFI and SAIDI of this system are 117.63 Intr./customer/year and 183.83 hr/customer/yea, respectively. Even though, improvements are being observed reliability indices are beyond EEA?�?s standard., The revenue lost by the power utility is around 4.579. Billion birrs in half of year approximately 9 billion birrs per year. The reliability of rehabilitated and upgraded distribution of Adama city has been computed using ETAP software which results in SAIF value of 139.49 Intr./customer /year and SAIDI value of 148.26 hr/ customer /yr to verify the result. To improve the reliability of the distribution system, this thesis proposed one additional distribution substation. This results in significant improvement distribution system based on rehabilitant distribution system. this results SAIFI and SAIDI, 62.194 fr/customer /yr and 66.4688.75 hr/customer/yr respectively, which is most reliable distribution system for Adama city.