Nonlinear adaptive decentralized stabilizing control of multimachine systems

This work develops a design approach to nonlinear adaptive control system with unknown parameters and applies it to excitation control of power systems. The adaptive control strategy is formed by recursive way. The characteristic of the controller is that which involves a dynamic estimator of parameters and a general expression of nonlinear adaptive decentralized excitation control strategy for multimachine systems is acquired. In the control strategy, all of the feedback variables are local measurements and the control variable is merely relevant to the state variables of this generator and has no direct relation with the state variables or outputs of other units. Moreover, the control law is independent of transmission network parameters. Simulation results of a 6-machine 22-bus system manifest the validity of the nonlinear adaptive controllers. This work is supported by the National Natural Science Foundation of China (No. 59837270), National Key Basic Research Special Fund of China (No. G1998020309), and the Chinese National Key Science and Technology Tackling Project (No. 97-312-01-11-1a).