An effective forced islanding and load shedding scheme to prevent blackout

Blackouts in large interconnected power system can cause damage to equipment of power plants, interruption of production cycles, and great economic losses. In order to avoid these blackouts from occurring in the power system, an effective forced islanding scheme with a suitable load shedding scheme can be used. This paper proposes an algorithm that identifies the risk during an outage and forcefully splits the system into predefined islands to prevent the propagation of cascading failures across a transmission network and thereby reducing the possibility of a large-scale blackout. The scheme makes use of DC load flow studies and sensitivity factors, such as Line Outage Distribution Factor (LODF) and Generation Shift Factors (GSF), to calculate the overloads occurring due to the outage. For each outage, the forced islands to be formed are predefined. After splitting the system into islands, the islands are analyzed for stability. If they are found to be unstable, then an under-voltage load shedding scheme is adopted to bring the system back to stability. The proposed work is carried out on a sample 6 bus system using MATLAB program.