Abstract
This paper describes new approach to the synthesis of a multivariable control problem for a power system with the field flux decays of AC generator. The power system dynamics can be formulated as a class of nonlinear system in which are contained the product-type nonlinearities between phase-angle and field-flux linkage of the generator, and the dynamical system is represented by ordinary differential equations divided into linear and nonlinear terms. Moreover we have introduced the measurable nonlinear function values consisting of the terminal voltage and electrical power output of the generator as an output vector. In this paper, a feedback control law is derived by minimizing the finite-time integral performance index with a quadratic form of state vector, control vector and also nonlinear function vector of system. In this theoretical scheme, it is shown that the existence conditions of the control law are concerned closely with the minimal realization problem. Through the approach described above, the feedback controller for a synchronous generator with field and governor dynamics connected to an infinite busbar by transmission line is synthesized by using the optimization method. The simulation results are given numerically for damping large oscillations associated with transient conditions in this system.
