Coordinated DFIG Wind Turbines and Solar PV Generators for Inter-area Oscillation Damping

Intermittent power injection from renewable energy sources such as wind and solar farms may cause low damping of critical inter-area oscillation modes. However, such renewable sources may be located in some areas with higher controllability of inter-area oscillations than the conventional synchronous generators. By controlling the reactive power output of such renewable sources, the superior damping effect of inter-area oscillations can be anticipated. This paper proposes the robust control design of power oscillation dampers of wind turbines with doubly-fed induction generator and solar photovoltaic generators to damp inter-area oscillations in large-scale power systems. The coordinated robust controllers are designed to achieve the desired damping and robustly operate against system uncertainties such as noises, external disturbance, and intermittent power. Study results indicate that the damping effect of coordinated wind and solar farms is higher than that of conventional power system stabilizers under various operating conditions.