Evaluation of Stability Region by Fuzzy-Type Lyapunov Function for Electric Power Systems

Governor Control for One-Machine Infinite Bus Model System

Abstract

Decentralized control is generally preferable to centralized one for large scale system. For the decentralized control of multi-machine electric power system, some decentralized systems are constructed by a model equation based on one-machine infinite-bus model system, and the stability analysis of each decentralized system guarantees the stability of the whole system. In this case, the stability analysis of one-machine infinite-bus model system becomes one of basic subjects for multi-machine system.
This paper treats a one-machine infinite-bus model system with governor as a simplest one including controller. First, the swing equation is rewritten into a fuzzy system, and the stability theorem is applied to the system. Next, the P-region which is necessary for the proof is discussed, and feedback gains for the fuzzy control input of the governor are determined. Finally, the control responses and the stability regions are considered. As a result, it is summarized that the stability of the model system can be rigorously analyzed by the proposed method, and the stability region can be evaluated by the fuzzy-type Lyapunov function.