μ-Synthesis-based robust L1 adaptive control for aeropropulsion system test facility

Abstract

For Aeropropulsion System Test Facility (ASTF) applied in aero-engine performance testing, it is critical to accurately control the pressure and temperature of the airflow to simulate the flight environment. This article presents a μ-synthesis-based robust L1 adaptive control method for ASTF to achieve excellent control performance within a wide working envelope. A μ controller based on a reference model is first designed as the baseline, which can address the coupling effect and guarantee the desired dynamic despite uncertainties. Thereafter, an L1 adaptive compensation term is incorporated to cancel out the large (matched and unmatched) uncertainties, and then recover the baseline performance. This control scheme augments the μ controller to control the ASTF over a wide working envelope and avoids complex gain scheduling design. Furthermore, μ controller can still ensure the robust performance of the closed-loop system even if the adaptive compensation is inadequate. Numerical simulations are performed on high-fidelity nonlinear model to verify the effectiveness of the proposed method. Compared with other state-of-the-art techniques, the robust L1 adaptive control possesses better performance and robustness.