Abstract:
The interconnected system of EEPCO consists of large interconnected power systems
with dispersed and geographically isolated generators and loads connected by long
transmission lines. This poses high chances of disturbances and contingencies more ancl
more frequently which affected the customers. Following the occurrence ol these
disturbances, the power system transmissions arc loaded to their Ii 111 its and the
substations voltage deviate from the normal limit range thus making it susceptible to
partial or total blackout under minor/major disturbances.
In this thesis, a comprehensive assessment of static security problem of Ethiopian
Electric power interconnected transmission system has been conducted and enhancing
mechanisms have been addressed. The study has employed conventional power llow and
contingency analysis for assessing the security status of the system using power world
simulator software. A standard N-1 criterion has been used for contingency analysis.
which holds that the system must remain functional after one contingency. In accordance
with this, transmission lines and transformers overloading, and substation voltage limits
deviation have been obtained both in normal operation and tor N- l contingency. linall «,
lo mitigate these problems, necessary security enhancement measures have been
presented. Consequently, tile problem of transmission l ines and transformer overloading.
and bus bars voltage limit deviation from the normal limits (: 1 : 10%) have been completely
solved for normal operation condition. These problems have also been reduced
dramatically in N-1 contingency analysis of the system.
