Fast reference governors for systems with state and control constraints and disturbance inputs

Reference governors are applied to closed-loop tracking systems that are li near and discrete time and have constraints on state and control variables. Earlier results are extended in significant ways. Disturbance inputs, whos e values belong to a specified set, are allowed and a general class of refe rence governors is introduced. Each governor in the class guarantees constr aint satisfaction for all reference and disturbance inputs, Moreover, if th e reference input is ultimately confined to a neighbourhood of a constraint -admissible constant input, the eventual action of the reference governor r educes to a unit delay. By appropriately selecting reference governors from the allowed class it is possible to simplify significantly their implement ation. The increase in on-line speed of operation overcomes prior limits on the practical application of reference governors. Algorithmic procedures a re described which facilitate design of the reference governors. Several ex amples are presented. They illustrate the design process and the excellence of response to large inputs. Copyright (C) 1999 John Wiley & Sons, Ltd.