Affiliations: [a] Department of Electrical Engineering, AU College of Engineering, Andhra University, Visakhapatnam-530003, AP, India | [b] Department of Electrical and Electronics Engineering, P.V.P. Siddhartha Institute of Technology, Kanuru, Vijayawada, AP-520007, India | [c] Department of Electrical and Electronics Engineering, J.N.T.U. College of Engineering, Kakinada-533003, AP, India
Abstract: The network contingencies in power system often contribute to over-loading of network branches, unsatisfactory voltages and also to voltage collapse. To maintain security against voltage collapse, it is desirable to estimate the effect of contingencies. For security enhancement, remedial action against possible network overloads in the system following the occurrence of contingencies is required. Line overloads can be removed by means of generation re-dispatching and by adjustment of reactive power control variables such as tap-changing transformers, generator excitations, and shunt reactive power compensating devices. This paper presents fuzzy logic composite criteria to evaluate the degree of severity of the network contingency. A Particle Swarm Optimization (PSO) based algorithm was also proposed for solving the Optimal Power Flow (OPF) problem to alleviate line overloads. The proposed PSO algorithm identifies the optimal values of generator active-power output and the adjustment of reactive power control devices. Simulation results on IEEE 14, 30, and 118-bus test systems are presented and compared with the results of other approaches reported in the literature.