Robust Stability of Uncertain Sampled Data Time Delay Systems with Application to Turbine Engine Control

摘要

Future aircraft control systems will be based on distributed engine control methodology since it provides many advantages, but a network in the control loop gives rise to communication constraints. Secondly, turbine engine components undergo deterioration due to constant usage and the stability of such deteriorated turbine engine systems is significantly affected due to these communication constraints. Hence, robust stability analysis is essential in reconfiguring the operating life cycles of turbine engine systems in case of distributed control implementation. In this paper bounds are presented to ensure stability of uncertain sampled data time delay systems and apply them to the deteriorated turbine engine case. The formulation of the proposed bounds is novel since till now the problem of obtaining bounds taking the exponential structure of the perturbation, sampling period and the communication constraints into consideration has rarely been tackled in the literature. Discrete-time Lyapunov stability criterion is used to obtain reasonably sufficient stability margins. Linearized state space models obtained from the high fidelity turbofan system developed by NASA, known as CMAPSS-40K (Commercial Modular Aero Propulsion System Simulation), are used to show the significance of the problem formulation and to verify and validate the proposed robust stability bounds.