INPUT SELECTION AND LOCALIZED DISTURBANCE REJECTION

The control structure selected has a strong effect on the performance of a closed loop system with respect to its disturbance rejection capa bility. A special capability-localizable disturbance rejection is stud ied in this work. It is shown that this capability can be related to a particular set of manipulated variables. A new measure, the input dis turbance alignment (IDA) is proposed to identify these inputs. Some im portant features of the new indicator and its relationship with other well-known controllability measures are presented. The case studies in cluded show that the IDA can be used for efficient selection of manipu lated variables from a large number of candidate inputs. These then fo rm the best control structure for localized disturbance rejection. (C) 1998 Elsevier Science Ltd. All rights reserved.