Generation rescheduling using multiobjective bilevel optimization

Abstract

This paper presents a new multiobjective optimization method that can be used for generation rescheduling inpower systems. Generation rescheduling in restructured power systems is performed by the system operator for differentoperations like congestion management, day-ahead scheduling, and preventive maintenance. The nonlinear nature of theequations involved and the constraints on decision variables pose a challenge to find the global optimum. In order to findthe global optimum using a genetic algorithm, a bilevel optimization method is proposed. In the proposed multiobjectiveoptimization method, the objectives are classified as primary and secondary based on their relative importance. Thebest solution is found using the secondary objective from the acceptable solutions of the Pareto-optimal front in theprimary objective plane. As the financial feasibility and adherence to emission limits are of higher importance, theprimary objectives considered are minimization of generation cost and emission. The secondary objective considered isreliability, to find the most reliable solution from the set satisfying the primary objectives. The proposed technique isvalidated on the IEEE 30-bus system and the results are presented.