一种弹性机翼的颤振主动抑制与阵风减缓方法

A Robust Active Flutter Suppression and Gust Alleviation Method for Flexible Wing

由于航空器的弹性性质,飞行过程中飞行参数的不断变化会引发运动稳定性和阵风响应特性的改变。在设计颤振主动抑制或阵风减缓控制器的过程中,以某一飞行状态为基础设计出的控制律往往不能保证在一定飞行参数范围内的性能。针对此问题,首先通过非定常气动力有理拟合方法建立时域连续阵风响应状态空间方程,再考虑模型随马赫数和动压的变化特性建立线性参数变化(LPV)模型。最后以线性参数变化模型为基础构造了包含动压和马赫数参数不确定性的线性分式变换模型,并设计了机翼颤振主动抑制与阵风减缓鲁棒控制器。结果表明,对于算例机翼,其在马赫数0.5~0.7范围内的颤振动压平均增大10%,且在飞行参数不断变化的时域仿真中,翼尖过载的均方根值降低51.4%。

The stability characteristics and dynamic responses of a flexible wing vary with flight conditions. During the design process of a controller for active flutter suppression or gust alleviation, the controller＇ s performance can- not be sustained when flight conditions change if it is designed on the basis of a single flight condition. To solve this problem, the time domain state-space model is firstly built up with rational function approximation of the unsteady aerodynamics, then the model＇s dependence on Math number and dynamic pressure is taken into account by con- strueting a linear parameter-varying （LPV） model. A linear fractional transformation model is finally built up on the basis of the LPV model; after which a robust controller is designed for active flutter suppression and gust allevia- tion. The results on a test wing show that the flutter dynamic pressure increases about 10% when the Mach number varies between 0. 5 and 0. 7. As can be seen from the simulation results, when the flight parameters keep varying, the root-mean-square of the wing tip overloads decreases by 51.4%.