Decentralised nonlinear equilibrium point adaptive control of generators for improving multimachine power system transient stability

Decentralised nonlinear control of generator excitation and turbine governor based on the feedback linearisation approach is proposed. To make the proposed nonlinear control possess adaptive ability under the changing conditions of power systems, the extended observation decoupled state space in which mechanical power is considered as variable is proposed, and the local stability of the postfault equilibrium point is established rigorously from a mathematical viewpoint. Nonlinear simulations are performed in a three-machine power system and in the ten-machine West Japan power system, and the effectiveness of the proposed nonlinear control and the convergence characteristics of the post-fault equilibrium point observer are validated.