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

Abstract

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.