A novel controller for gas turbine engines with aggressive limit management

A new control scheme is proposed for turbofan engines, where the objective is to transfer a regulated output between two setpoints, with the additional requirement that a set of limited outputs remain within prescribed bounds. The strategy is based on the traditional max-min selector system, replacing linear regulators with sliding mode controllers where the sliding variable for the limited outputs is de?ned as the di?erence between the output and its limit. The motivation for the replacement lies in several recently-noted shortcomings associated with the use of linear regulators in the traditional scheme. The proposed technique effectively removes the weaknesses of the traditional scheme. The paper points out these de?ciencies and describes the proposed method, establishing overall system stability. The invariance properties leading to limit protection are also elaborated. A design methodology involving a mixed H∞=H2 multi-objective feedback gain synthesis is proposed and demonstrated through a design example. Practical applicability is further demonstrated by simulation using a high-fidelity nonlinear engine simulator (C-MAPSS). © 2011 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.