放宽静稳定性大型客机的LQR控制律设计

LQR in control law design for a relaxed static stability large civil aircraft

论述了法向过载信号反馈在放宽静稳定性大型客机自动驾驶仪增稳控制中的作用。在自动驾驶仪纵向内回路控制律中引入法向过载信号,构成了国际先进客机的C*控制律构型;反馈系统的输出信号,选用LQR设计方法同时闭合客机纵向的内回路和姿态、油门回路,形成了输出跟踪器,并设计了性能指标与反馈参数。以B707为例,建立了其着陆进近阶段的非线性模型,配平并线性化,用获得的控制律进行数字仿真验证。结果表明,内回路增稳效果良好,C*响应曲线在最佳响应区,姿态响应和速度保持都达到了满意的效果。

Feedback of normal overload in the autopilot＇s inner loop of longitudinal control law can form the C-star control configuration for the relaxed static stability large civil aircraft and increase its static stability.In this article,the output-feedback tracker closes the inner loop,the attitude loop and the thrust loop simultaneously by means of the LQR method.The nonlinear model of B707 civil aircraft is established,trimmed and linearized.After the control parameters are designed,the digital simulation is performed.The simulation results show that the transient and steady-state responses are satisfactory.And the augmentation effect meets the requirements well.