An improved whale optimization algorithm for the design of multi‐machine power system stabilizer

An improved whale optimization algorithm (IWOA) for the design of a robust power system stabilizer (PSS) for the multi-machine power system is developed in this paper. Tuning of PSS parameters using the proposed IWOA is carried out by minimizing a multi-objective function comprising the damping ratio and damping factor of lightly damped oscillating modes of all the generators. The advantage of considering the objective function is that the lightly damped and undamped oscillating modes of all the generators can shift to a prespecified zone of the s-plane. The performance of the proposed IWOA is tested on standard benchmark test functions and compared with familiar optimization algorithms. The efficacy of the proposed design technique is tested on three benchmark test systems: three-generator nine-bus system, two-area four-machine interconnected system, and the New England 10-generator 39-bus system working on various operating conditions under several typical disturbances. The potential of the proposed method is demonstrated through eigenvalue analysis. The proposed IWOA-based PSS is compared with the other stabilizers to show its efficacy.