Decentralized nonlinear stabilizing control using state-space linearization

This paper describes a nonlinear stabilizing control scheme for generator and simulator test results to verify effects of the proposed control system on improvement of power system stability. In order to improve the stability in a wide range operating condition, nonlinear control schemes for generators have been proposed. The authors have confirmed the effect of the nonlinear controller by digital simulation. Then, the generator control system was designed using an exact linearization approach toward a one machine-infinite bus model, and the use of a digital signal processor (DSP) as an external controller enabling realization of a nonlinear control block diagram by software. Furthermore to evaluate the dynamic performance of this controller for nonlinear operating points, simulator tests were performed using a real-time digital simulator (RTDS). The effect of the nonlinear control was compared with the effect of (ΔP+Δω) input type conventional linear PSS.