Determination of worst case loading margin using Genetic Algorithm

Estimation of voltage stability margin is essential for operation of the system with an adequate security margin. This paper presents a new technique to determine the shortest distance to voltage instability. The problem of determining the closest saddle-node bifurcation point (CSNBP) is formulated as an optimization problem and solved using genetic algorithm. The method is capable of handling various operational constraints and can determine the CSNBP accurately even if the transfer limit surface is not smooth. The proposed approach has been applied on a simple radial system and IEEE 14-bus system. Simulation results show the validity and feasibility of the proposed method.