Distributed frequency regulation in smart grids

Abstract

We present and analyze distributed control schemes for frequency regulation in a smart grid. We use energy storage, conventional generators, wind generators and demand response to provide frequency support while having no communication or data sharing between them. All participants observe the system frequency and act independently in a decentralized manner to provide frequency regulation. We also propose a novel control scheme for frequency support by energy storage in which the power output of energy storage changes proportionally with the reduction in available energy in energy storage. This prevents any sudden drop in system frequency and provides other participants an opportunity to compensate for the reduced power due to discharge of energy storage. We use our methods to observe the frequency regulation in a three area power system having conventional generators, wind generators energy storage and demand response. Our results show that the addition of demand response improves the value of initial frequency drop, settling frequency and settling time. Use of energy storage further improves these characteristics.