Active Disturbance Rejection Control for Hypersonic Flutter Suppression Based on Parametric ROM

Abstract

This paper presents an active disturbance rejection control algorithm (ADRC) to suppress the hypersonic flutter of a three-degrees-of-freedom (3-DOF) two-dimensional (2D) airfoil operating in multiparameters space. In this study, two key issues need to be addressed. The first one is the construction of the reduced-order model (ROM) of quasi-steady aerodynamic forces in multiparameter space. To solve this problem, a parametric reduced-order model (PROM) based on the adaptive proper orthogonal decomposition (POD) is developed to efficiently predict the quasi-steady aerodynamic forces at an arbitrary point in the given multiparameters space. The accuracy of the PROM is validated by the direct computational fluid dynamics (CFD) computations for flutter and limit cycle oscillation (LCO) prediction. The second issue is the design of the control law for an aeroservoelastic (ASE) system constructed by a parametric black-box aerodynamic model. Considering the black-box characteristics of a controlled object, we use an error-based feedback control law named ADRC to suppress the flutter instability of the system. Furthermore, in order to improve the rapidity in responses and the robustness of the ASE system, we propose an SVM-ADRC strategy that features embedding the least squares support vector machine (LS-SVM) into the ADRC controller. Hypersonic ASE simulation results show that the proposed SVM-ADRC controller can effectively suppress the hypersonic flutter over a wide range of parameter variations, and is more robust than the standard ADRC controller.