Design and application of decentralized nonlinear H∞ control for stability enhancement in power systems

The paper presents a method of designing a decentralized nonlinear H_∞ excitation control of the generator in power systems. The proposed controller is utilized to damp inter-area oscillations and enhance power system stability. The decentralized controller design procedure for nonlinear systems is presented by using the Hamilton-Jacobi inequality approach. The control is local or decentralized in the sense that the controller depends only on the information available locally. The effectiveness of the proposed decentralized nonlinear H_∞ controller is demonstrated through digital simulation studies on a nine-bus power system with three generators buses and three loads buses. The digital simulation studies are conducted using the PSCAD/EMTDC software package.