考虑管路的飞机液压刹车系统压力振荡分析

飞机液压刹车系统通常采用压力伺服阀控制刹车压力，由于布局限制，压力伺服阀和刹车作动器之间往往存在较长的液压管路.管路会给系统引入欠阻尼的频率特性，而且该特性会与压力伺服阀固有的局部压力闭环结构相耦合，使得压力伺服阀的输出压力容易出现振荡、失稳现象.因此通过在飞机液压刹车系统建模中考虑管路模型，在频域上分析了压力伺服阀与管路、容腔耦合的现象和原因，具体给出了管路参数和油液参数变化对压力闭环的影响，并通过时域仿真进一步验证了频域分析的结论.同时分析了匹配设计管路、增加系统阻尼和降低系统增益3种避免压力闭环控制振荡失稳的方法.为飞机液压刹车系统的设计与优化提供了理论参考依据.

Pressure oscillation analysis of aircraft hydraulic braking system considering pipeline

Pressure servo-valve is usually used for aircraft hydraulic braking system, and the brake pipeline between the valve and the actuator is usually long. The long pipeline brings under damping frequency characteristic into the system, which will couple with the local close-loop pressure control structure of pressure servo-valve, and make pressure control oscillate easily. Based on a model considered pipeline for the hydraulic braking system, the reason of pressure servo-valve and pipeline coupling was analyzed. The influence of the changes in pipeline and oil parameters on pressure control was given. Simulations of the pressure control of aircraft hydraulic braking system were conducted to verify the frequency analysis. And three solutions for avoiding pressure oscillation, including matching design of pipeline, increasing the system damping and reducing the gain were also analyzed. Theoretical reference for the design and optimization of the aircraft hydraulic braking system was provided.