Abstract:
This study presents reliability assessment and improvement of the distribution system of Ambo
Town, Ethiopia. As the numbers of power interruption are posing a great problem to the country's
economy and the lives of people, solving this problem is essential. The reliability of electricity has
affected social well-being, water supply, public health, education system, communication services,
and community growth as all in Ambo Town.
In this thesis, the assessment result of power distribution reliability for 15KV Ambo town feeder,
which supplies the community of the Ambo town, has been analyzed without any improvement at
the first stage and finally, the improvement of reliability has been done by using a smart recloser
and Tie switch. The smart recloser is an important element for Fault detection, isolation and
restoration.
Interruption data of two years have been used as the base year. ETAP (Electrical Transient
Analyzer Program) software has been used to verify the improvement of reliability indices.
Different mitigation alternative step by step at a reasonable cost and low values of reliability
indices such as SAIDI, SAIFI and EENS has evaluated.
The study shows that significant reliability improvement SAIFI has been improved by 84.87%
compared with base years average reliability indices values of Ambo town feeder. Additionally,
SAIDI and EENS have been improved by 84.56% and 84.31%, respectively. The cost of the
proposed solution can save 825,164.82 ETB per year from only unsold energy of Ambo town
feeder with 3.86 yeas payback period.
