Abstract
A large-scale power system usually consists of several subsystems and the subsystems are connected weakly through tie lines or long distance transmission lines. As a result, there exist two types of oscillatory modes, one of which is local modes representing the dynamics of one subsystem and the other of which is global modes representing the dynamics of multiple subsystems. This property makes it advantageous to utilize decentralized and hierarchical control method for improving the stability of such a large-scale power system. In this paper, a novel control method called decentralized and hierarchical eigenvalue control, which aims at improving the steady-state stability of the large-scale power system, is proposed. Under this control scheme, first, stabilization of the local modes utilizing eigenvalue control is performed in each subsystem, and second, eigenvalue control of the whole system is performed to stabilize the global modes. Numerical examples make it clear that the proposed method can improve the steady-state stability of power system much more efficiently than the centralized eigenvalue control.
