Decentralized H∞ controller design

This paper is concerned with the design of decentralized controllers which attain the H-infinity performance specifications. In most designs of decentralized controllers, controllers are designed for diagonal approximation of plants. But few discussions have been made on the approximation. In this paper, the approximation problem which takes account of the general H-infinity performance specifications is considered. The metric is defined by the parametrization of all the plants and is used in the approximation problem. A numerical design method is also presented in this paper.