Abstract:

To reduce or eliminate the forcefight phenomenon of single feedback loop of redundantchannels, the mechanical transmission structure, plate valves, parallel actuating cylinders, spindle and pipelines of the whole control system were modeled and simulated to obtain the bandwidth frequency of the system and the fightingforce caused by the internal asymmetry of the steeringgear.Then the influences of the system's input ratio,the size of valve's dead zone and the gradient of the valve's open area on the system's fightingforce and response speed were studied. Simulation results show that setting the dead zone of the valve which controls the feedback loop smaller is conducive to the decrease of system's fightingforce, and with the increase of the input ratio the fightingforce will be reduced greatly and the bandwidth will be increased and with the reduce of the valve's dead zone, and the increase of the gradient of the valve's open area, the bandwidth frequency increases, but have no influence on the fightingforce. Therefore, increase the input ratio and reduce the valve's dead zone or appropriate increase the gradient of the valve's open area can improve the dynamic and static performance of the system. Finally, a method of setting a variable orifice put forward  to reduce system's fightingforce when these structural parameters cannot be changed, and simulation results prove its feasibility.

Key words: forcefight phenomenon, input ratio, valve dead zone, gradient of the valve open area, variable orifice

摘要：

为了减缓或消除单反馈回路的余度舵机上的力纷争现象，并同时改善系统响应速度，在对飞机副翼舵面的结构进行分析的基础上，对系统的机械传动部分、板阀、作动筒、管路、转轴等进行建模仿真分析，得到了系统的带宽频率及由于舵机内部的不对称性所导致的系统纷争力大小。进一步研究了系统的输入比、板阀死区大小、板阀开口面积梯度对系统纷争力大小及系统响应速度的影响。仿真结果表明，将控制反馈回路的板阀死区设置得较小,有利于系统纷争力的减小；增大系统输入比可大幅度减小系统纷争力并提高带宽；减小板阀死区或增大开口面积梯度可提高系统带宽但并不影响纷争力的大小。因此合理设置两板阀死区，提高输入比、减小板阀死区或增大板阀开口面积梯度均可改善系统的动静态性能。在以上结构参数无法更改的情况下，提出了设置可变节流孔的方法减小系统纷争力，仿真结果证实了该方法的有效性。

关键词: 力纷争现象, 输入比, 板阀死区, 板阀开口面积梯度, 可变节流孔