Forced islanding and restoration scheme to prevent blackout for improving power system security

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, a forced islanding scheme with suitable restoration sequence will be effective. This paper proposes an algorithm that identifies the risk during an outage and forcefully splits the system into predefined islands. The scheme makes use of DC load flow studies and linear sensitivity factors to calculate the overloads occurring during an outage. An under-voltage load shedding scheme is adopted to bring the system back to stability in case of unstable islands. Also, a restoration sequence has been formulated. The proposed work is carried out on a sample 6 bus system using MATLAB program. This approach can also be applied in smart grid environments to improve power system efficiency and reliability.