Robust design of multimachine power system stabilizers using fuzzy gravitational search algorithm

This paper presents a novel Fuzzy Gravitational Search Algorithm (FGSA) for optimal design of multimachine power system stabilizers (PSSs). The FGSA technique is characterized as simple, robust and capable to solve difficult combinatorial optimization problems. For achieving optimal tuning of PSS parameters, the problem is formulated as an optimization problem with the time domain-based objective function over a wide range of operating conditions and is solved by the proposed FGSA technique. The performance of the proposed FGSA based-PSS design is validated for two multimachine systems: a 3-machine 9-bus system and a 10-machine 39-bus. The effectiveness and robustness of proposed method is demonstrated using many performance indices. The results prove that the proposed FGSA assures a well damping to the electromechanical modes of oscillations for a wide range of system operation conditions. The superiority of the proposed method is proved compared to different optimization methods.

► This paper presents a novel FGSA method for optimal design of PSSs.
► Low frequency oscillations are detrimental to the goals of maximum power transfer.
► The results showed that the FGSA can provide better and faster solutions.
► We develop a robust PSS with particular emphasis on achieving a minimum closed loop.