倾转旋翼动载荷高阶谐波主动控制

Tiltrotor Vibration Load Reduction Based on Higher Harmonic Control

针对倾转旋翼动载荷抑制问题,发展了倾转旋翼/弹性机身耦合动力学计算方法,基于广义卡曼滤波方法与最优控制原理,研究了桨距高阶谐波控制(HHC,Higher Harmonic Control)在倾转旋翼减振中的应用,明确了控制流程与控制策略.以XV-15倾转旋翼机为例,开展了旋翼动载荷高阶谐波控制仿真,结果表明:在传递矩阵在线识别条件下,旋翼桨毂3Ω载荷分量显著降低,降幅最大90%,最小18%.施加高阶桨距控制后,桨尖区域升力随方位角的波动幅度明显降低,表明HHC方法主要通过削减桨叶高频气动力实现旋翼减振.

To study the dynamic issue of a tiltrotor aircraft,an analytical method was established for the tiltrotor-fuselage coupled model.Based on the generalized Kalman filter method and optimal control theory,the application study of the higher harmonic control(HHC)in the vibration reduction of a tiltrotor was conducted,the control process and control strategy were constructed.Taking XV-15 as an example,the closed-loop vibration control on a tiltrotor was simulated through HHC method.The results show that 3Ωhub loads were significantly reduced with a transfer matrix on-line identification,the maximum and minimum reduction are respectively 90%and 18%.When HHC control was applied to the tiltrotor,the blade lift of the outboard section showed a significant change with rotor azimuth.It can indicate that the vibration control effect mainly comes from the reduction of the high-frequency aerodynamic force.