DECENTRALIZED H-INFINITY CONTROL FOR POWER-SYSTEM STABILITY ENHANCEMENT

This paper presents a method of designing a decentralized H-infinity g enerator excitation control of a power system. The proposed controller is utilized to damp inter-area oscillations and enhance power system stability. The decentralized controller design procedure for a linear composite system is presented in terms of positive definite solutions to modified algebraic inequalities. The resulting controller guarantee s closed-loop stability and the H-infinity-norm bound an disturbance a ttenuation. The control is local or decentralized in the sense that th e control of each generator depends only on the information available at that generator. The effectiveness of the decentralized H-infinity c ontroller is demonstrated through digital simulation studies on a two- machine power system. The digital simulation studies are conducted usi ng a PSCAD/EMTDC software package. The simulation results show that th e controller contributes significantly to the damping of inter-area os cillations and the enhancement of power system stability. (C) 1998 Els evier Science Ltd. All rights reserved.