Nowadays the stability, reliability, sustainability and security of power system are the main concerningrnissues in Ethiopia because of frequently happening disturbances which will lead to total or partial powerrnsystem blackout. When disturbances occur in power grid, monitoring and controlling of a power system arernrequired to stop the grid degradation, restore it to a normal state, and hence minimize the effects of disturbances.rnHowever,rninrnwidernarearnpowerrngridrnresultingrnfromrnlargernandrncomplexrninterconnectionrnofrnpowerrnsystemrnrnnetwork,rnclassicalrnsystemsrnbasedrnonrnmanualrnoperationrnandrndecisionsrnarernnotrnablerntornrapidlyrnrespondrnforrnrndisturbances,rnwhichrnmayrncausernarnlocalrnorrncompleternsystemrncollapse.rnThereforernthernintroductionrnofrnautomatedrnrnSCADArnrnsystem with advanced measurement and very fast communication technologies provide betterrnways to detect rapidly the disturbances and protect the overall grid from the propagation of the fast cascadingrnoutages.rnAutomationrnsystemrnimprovernthernperformancernbyrntakingrnadvantagernofrnfasterrncomputerrncontrolrnrninsteadrnofrnhumanrnrnreaction times and also used to increase the efficiency of control by trading off highrnpersonnel costs for low computer system costs. rnrnThis thesis presents the design of an automated SCADA system that can prevent the grid system fromrnblackout in real time through active and reactive power balancing. Active power and reactive power of thernsystem are the most essential parameters in the monitoring, control, and protection of power systems andrnelectric equipments because when a fault or a signiï¬cant disturbance occurs in a power system, the frequency andrnvoltagernvariesrninrntimernandrnspace. rnrnA modeling of electrical system elements was developed to have a complete one line diagram of the existingrnnetwork using DIgSILENT power factory software version 15.1. The study has employed conventionalrnpower flow and dynamic analysis for assessing the stability and reliability of the system. Different type ofrnfaults has been used for the analysis, which leads the system to cascade outage. Finally, to mitigate thesernproblems, necessary control measures have been presented. The result shows that whatever any disturbancernexperienced to grid has been controlled automatically without operator intervention and lead to normalrnoperation condition. From the test results, the proposed technique presents better controlling method inrncomparison with that of the existing manual based control system in black out mitigation along with improvementrninrnstabilityrnofrnthernsystem. rnrnThe method is implemented on the whole EEP grid and tested on specifically for northern and north westernrnregion.