Load frequency controller design via BAT algorithm for nonlinear interconnected power system

•BAT algorithm is proposed for tuning the gains of PI controllers for LFC design.•A two area power system is considered to demonstrate the proposed method.•The design problem of LFC is formulated as an optimization problem.•The effectiveness of the proposed algorithm is confirmed compared with SA. BAT algorithm is proposed in this paper for optimal tuning of PI controllers for load frequency controller (LFC) design. The problem of robustly tuning of PI based LFC design is formulated as an optimization problem according to time domain objective function that is solved by BAT algorithm to find the most optimistic results. To demonstrate the effectiveness of the proposed method, a two-area interconnected power system is considered as a tested system. To ensure robustness of the proposed control strategy to stabilize frequency oscillations, the design process takes a wide range of operating conditions and system nonlinearities into account. The simulation results are given to detect the superiority of BAT algorithm over Simulated Annealing (SA) in tuning PI controller parameters through different indices. Results evaluation show that the proposed algorithm achieves good robust performance for wide range of system parameters and load changes compared with SA.