A technique for load-shedding based on voltage stability consideration

This paper describes a new algorithm for load shed under emergency condition to avoid risk of voltage instability. For this purpose minimum eigenvalue of load flow Jacobian has been selected as proximity indicator. The amount of load to be shed is decided so as to maintain a threshold value of indicator and all load bus voltages within limit. Sensitivity of indicator with load shed has been utilized for problem formulation. A quadratic objective function has been selected in terms of minimization of load shed. This optimization is subjected to an equality constraint on indicator change. Inequality constraints on load shed have been accounted. For the purpose of optimization, Hopfield model in its modified form has been employed. This gives easy computational sequence. The developed algorithm has been tested rigorously on 91 bus Indian practical power system.