ABSTRACT
Electric power system is always subjected to different types of disturbances due to overload, tripping of generators, fault occur at any section of power system. Due to these disturbances, the system frequency will change, and the power system becomes unstable which can result in a major blackout if not immediately restored. To make stability in the frequency, typically conventional under-frequency load shedding (UFLS) method is widely used. However, these have the issue of not calculating the power imbalance and leading to un-optimal load shedding. The consequence might be excessive shedding of loads, that would impact the power system's efficiency, or small shedding of loads, leading towards the interruption of complete system. To address this issue, this thesis proposes a dynamic under frequency load shedding scheme to make sure the power system is functioning secure and effective in the event of significant disruptions. The proposed dynamic UFLS scheme is performed based on frequency and its rate of change with power swing equation.

The efficacy and robustness have been explored for this system in various cases of generators operating in the test system of IEEE 9 Bus. The frequency response for both conventional and dynamic UFLS schemes is compared for various generator tripping cases. It has been found that dynamic UFLS scheme provides more optimal results than the conventional scheme in terms of frequency overshoot, frequency undershoot, and the loads which are to be shed. Furthermore, this study proves that dynamic UFLS scheme is efficient and more reliable in the prevention of power blackouts in power system compared to conventional UFLS scheme.