Abstract
The frequency response analysis method are widely used in the parameters design of excitation system of generator. However, it can not be applied to a nonlinear excitation system, because it is difficult to calculate the synchronizing and damping torque of a generator with nonlinear excitation system precisely.
For extending the frequency response method to nonlinear systems, this paper proposes an approximation method to calculate the synchronizing and damping torque for nonlinear excitation systems, and using the frequency characteristics of damping torque to the parameters design of excitation systems.
As an example, the proposed method is applied in a generator control system with the power system stabilizer FUZZY-PSS. The power system stabilizer FUZZY-PSS consists of a fuzzy controller and a ΔP type PSS, which is a typical nonlinear control system. The application results show that the proposed method is very useful to aid the parameters design of such nonlinear systems, as well as the power system stabilizer FUZZY-PSS.
