Load frequency control in deregulated environment

Load frequency control is an important task in the power system. At present some power systems in China where electricity market is being practised control frequency by so called electricity pricing related to frequency. This approach has achieved some positive results, however it may cause stability problem. This paper studies the use of real-time pricing to control frequency theoretically. By incorporating the optimal price for frequency into real-time pricing, the pricing to control frequency is simple, effective and can ensure that the system is asymptotically stable. A simple example system is used to show the features of different frequency control approaches.