KRYLOV SUBSPACE METHODS FOR SOLVING LARGE LYAPUNOV EQUATIONS

Published versio

Implicitly restarted Krylov subspace methods for stable partial realizations

Published versio

A Characterization of all Solutions to the Four Block General Distance Problem

All solutions to the four block general distance problem which arises in H^∞ optimal control are characterized. The procedure is to embed the original problem in an all-pass matrix which is constructed. It is then shown that part of this all-pass matrix acts as a generator of all solutions. Special attention is given to the characterization of all optimal solutions by invoking a new descriptor characterization of all-pass transfer functions. As an application, necessary and sufficient conditions are found for the existence of an H^∞ optimal controller. Following that, a descriptor representation of all solutions is derived

OBLIQUE PROJECTION METHODS FOR LARGE-SCALE MODEL-REDUCTION

Published versio

The four block distance problem in H[infinity] control

Imperial Users onl

H infinity OPTIMAL CONTROL OF A SYNCHRONOUS TURBO-GENERATOR.

The use of H infinity optimal control methods in improving the performance of synchronous turbogenerators is investigated. The investigation is based on a single-machine infinite bus system. An H infinity controller is used in addition to the automatic voltage regulator and speed governor which are fitted as standard equipment on most large turbogenerator sets. The results compare favorably with those obtained using other multivariable design methodologies such as linear quadratic optimal control