Robust fractional order PID stabilizer design for multi-machine power system using grasshopper optimization algorithm

To overcome the deficiencies of traditional gradient-based methods and other meta-heuristic algorithms, in this study, a new meta-heuristic technique, grasshopper optimization algorithm (GOA), is proposed to use in the robust design of power system stabilizer (PSS) with fractional order proportional-integral-derivative (FOPID) controller structure. The problem of setting the FOPID type PSS parameters has been transformed into an optimization problem with a time domain based objective function and solved with GOA. The proposed approach was applied to a multi-machine power system exposed to different loading conditions and faults. The performance of the proposed GOA-based newly designed FOPID structured stabilizer (GOA-FOPIDPSS) is compared with GA-, ABC- and also proposed GOA-based conventional structured stabilizers. The superiority, potential and robustness of the proposed stabilizer are confirmed through nonlinear simulation studies and some dynamic performance indices. The analysis results show that the proposed GOA-FOPIDPSS controller gives excellent damping performance to low frequency oscillations under different faults and wide operating conditions.