Passivity-based robust control for power systems subject to wind power variability

As wind generation becomes a significant portion of total energy production, wind power variability will introduce more variability in system frequency. This paper presents a method to improve primary control for frequency regulation in large-scale power systems with high wind power penetration. To assure system stability, a passivity-based framework is developed for power systems by introducing a storage function derived from the entropy of individual generators. Tellegen´s theorem is invoked to derive the storage function for the entire power network. Given the network parameters and the point of interconnection of the wind farm, a single generator is selected to balance wind power fluctuations. A passive H_∞ controller is synthesized for the selected generator by using a passive reduced-order model of the large-scale power system. Simulation results of a 9-bus test system show the effectiveness of the passive H_∞ controller. This work also suggests several directions for further research.