Decoupling And Optimal Control Methods Of The Civil Aircraft Gust Suppression

As the little wing load, large civil airplane will generate great added wing load and reduce the ride comfort when it go through the gust. Appling the gust load alleviation system with active control technology, it can reduce the airplane's Gust load and improve the ride quality, it can enhance the airplane's virtual load too. At first, this paper bring forward a gust load alleviation project based on closed loop control. By adjusting the maneuver flaps and elevator, the project restrain airplane's response aroused by the gust. At second, this paper studied the decoupling and optimal control method, and separately designed the gust restrain controller for the airplane via two methods. Two kinds of gust restrain controller have well effect to load alleviation and stance disturbance restrain when the rigid airplane go through the random turbulent flow or gust. The investigation shows that the decoupling method is a feasible project, this method can achieve that one input only adjust one output by decoupling based on proper variable matching for multi-variable system.This paper studied optimal design method for the airplane's load alleviation controller. This method calculate the state space's shaping filter model by the turbulent flow's power table density model, and design the LQ optimal controller to airplane's expanded model included turbulent flow model. The simulation results show that the optimal controller based on this control method can not only convert the disturbance aroused by intensity turbulent flow to white noise weak disturbance, but also have well restrain effect to discrete gust.Gust load alleviation and the improvement of riding quality are important subjects in the development of large civil aircraft. Gust load alleviation programme based on loop control principles is firstly developed in this thesis. Secondly, the decouple methods and the optimal control methods are researched and used to respectively devise gust restraining controller of aircraft. Choosing suitable variables to decouple to achieve an input variable to regulate an export variable is feasible control gust load alleviation programme. Gust load alleviation optimal controller which expands turbulent flow model into the aircraft model is designed.The simulation results show the optimal method can invert the influence of great intensity turbulent flow into the influence of the low-energy white noise interference.