Abstract: In this paper a new robust load frequency controller for two area interconnected power system is presented to quench the deviations in frequency and tie line power due to different load disturbances. The Genetic algorithm (GA) controller designed here consists of two crisp inputs namely deviation of frequency and the other is derivative of frequency deviation. The Genetic algorithm controller output is the control input to each area. In practical systems, the conventional PI type controllers are applied for Load Frequency Control. In order to improve the performance of the LFC system, Genetic Algorithm (GA) approach is used to optimize the conventional controller gains and bias factors and a robust decentralized controller using Quantitative Feedback Theory (QFT) is proposed to solve the Load Frequency Control (LFC) problem in a restructured power system that operates under deregulation based on bilateral policy scheme. In each control area of this dynamical model, the effects of the possible contracts are treated as a set of new input signals. To validate the effectiveness of all the methods, the simulation has been performed using different controllers and compared. The simulation results substantiate the robustness and high performance of QFT controller.

Keywords: Restructured Power System, Load Frequency Control, Genetic Algorithm, Quantitative Feedback Theory, Bilateral Contracts.