A procedure to design wide-area damping controllers for power system oscillations considering promising input-output pairs

The expansion of the wide-area measurement system has provided some control strategies to improve the low-frequency oscillationmodes in electric power systems. One of these strategies is to use remote signals for a wide-area damping controller (WADC) to enhance the small-signal stability of the power system. However, the expansion of the Electric Power System increased the generator number connected to the grid, and then some challenges to the WADC design surged such as which input-output pairs of the WADC should be designed to improve the closed loop system damping. Typically, the WADC is a centralized controller and may have many design elements. The interactions among the elements may compromise the central controller design and its purpose. This paper proposes a procedure based on genetic algorithms in order to design a robust central controller. This procedure automatically chooses the input-output pairs of the central controller that will contribute to damping the low-frequency oscillation modes. The design procedure considers topological changes and time delay variations. Small-signal analysis and time-domain nonlinear simulations are carried out in the multi-machine Australian Equivalent Power System, an IEEE benchmark model for small-signal stability analysis.