ESO-MPC and Differential Flatness-Based Multivariable Control of High-Altitude Chamber Intake Systems

The intake system of high-altitude simulation chambers is characterized by strong nonlinearities, high coupling effects, and significant external disturbances, posing substantial challenges for achieving precise temperature and pressure regulation. Conventional control strategies frequently encounter challenges in effectively managing the system’s complex dynamics and multivariable coupling effects. To address these limitations, this paper presents an integrated control framework combining model predictive control (MPC) and extended state observer (ESO), with the differential flatness theory for simplifying control structure. The proposed methodology first establishes the differential flatness property of the intake system, enabling its transformation into an approximately decoupled canonical form. Based on this foundation, a cascaded control architecture is developed where ESO actively compensates for residual coupling terms and unmodeled disturbances, while MPC operates on the simplified plant model to coordinate multivariable control actions. The integration of ESO-based disturbance estimation with MPC’s predictive capabilities can achieve optimal balance between control precision and actuator effort minimization, ensuring high regulation accuracy while mitigating mechanical wear. Comprehensive simulation studies demonstrate that the proposed ESO-MPC scheme achieves 85% reduction in maximum temperature/pressure fluctuations. These results demonstrate an effective framework in handling strongly coupled nonlinear systems while maintaining implementation practicality, thus providing a promising solution for advanced environmental simulation applications.