考虑舵机时滞的阵风减缓主动控制律设计

Design of gust alleviation active control law considering time-delay of servo actuator

针对存在舵机时滞环节的气动伺服弹性系统,提出基于Padé近似和线性二次高斯(LQG)控制的阵风减缓主动控制律设计方法。利用Padé近似将舵机中的时滞环节线性化为一个高阶传递函数并引入气动弹性模型,建立线性的阵风减缓受控模型;利用LQG控制方法对线性化模型设计阵风减缓主动控制系统,并采用平衡截断法对所设计的控制系统进行降阶;利用Simulink将所设计的控制系统引入非线性模型中,得到von Karman连续阵风激励情况下系统的开/闭环响应情况。计算结果表明:根据所提方法设计的阵风减缓主动控制律能有效降低原气动伺服弹性系统的阵风响应,对研究对象机身过载的抑制在15%左右,而对翼根弯矩的抑制达到25%以上。

For the aersevoelastic model including servo actuators with time-delay segment,the design method of gust alleviation control system is proposed based on Padéapproximation and Linear Quadratic Gaussian(LQG)control method.Padéapproximation was used to linearize the time-delay segment to a high-order transfer function,and then this function was introduced to an aeroelastic model to establish a linear controlled model of gust alleviation.The LQG method was applied to design a gust alleviation control system based on the linear model,and the order of control system was reduced by the balance truncation method.By using Simulink,the designed control system was introduced to the nonlinear model to calculate the gust responses of open/closed systems under von Karman continuous gust model.The results showed that the gust alleviation control system based on the proposed method could effectively reduce the gust responses of the original model with time-delay.The overloads of the airplane were reduced by around 15%and the root bend moment was reduced by more than 25%.