SUMMARY
A Wide Area Measurement System (WAMS) can extend and effectively improve a controllers’capability of damping inter-area low-frequency oscillations in interconnected power systems. Thispaper presents an implementation of a Wide Area Fractional-Order Proportional-Integral-Derivative(WA-FOPID) damping controller to improve the system damping. A modal analysis approach isproposed to identify the best location for the WA-FOPID controller and the optimal combinationof input signals. The differential evolution optimization algorithm is used to determine the optimalcontroller parameters, and a nonlinear time-domain-based objective function is formulated tominimize the time-weighted errors. The proposed approach is successfully applied to a two-areafour-machine system, as well as to a practical multi-area power system. The nonlinear timedomainsimulations indicate that the proposed WA-FOPID damping controller can effectivelydampen inter-area oscillations and improve system stability, irrespective of the severity or locationof disturbances.