机载光电随动伺服系统稳速性能与动态特性优化

Optimization of rate stability and dynamic characteristics of airborne photoelectric servo system

为分析某型机载光电随动伺服系统的扫描稳速性能,首先以双惯量模型为基础,介绍了随动伺服系统的工作原理,根据伺服系统实际的机电参数搭建仿真模型。通过运行仿真模型,解析模型的扫描稳速曲线,归纳该系统的稳速性能特征。其次分别定位内外万向架对稳速性能的关键影响因素,使用描述函数法研究了外万向架速度振荡的产生机理。针对内外万向稳速性能影响因素分别给出优化措施,对外万向架采取了力矩均衡式的双电机控制,在无电流环的内万向架速度回路中加入了加速度回路。最后对优化措施进行实验验证,结果显示内万向架在加入加速度反馈后调节时间基本不变,速度调转时最大偏差由1.08 V减为1.00 V,内万向架的扰动隔离能力亦有提升。外万向架使用力矩均衡式的双电机控制后,齿隙造成的速度振荡得到了抑制,最大速度误差由0.4°/s降为0.2°/s。

To analyze the scanning rate stability performance of an airborne photoelectric servo system,firstly,based on the dual inertia model,the working principle of servo system is introduced based on the dual inertia model,anda simulation model is builtaccording to the actual electromechanical parameters of the servo system.By running the simulation model and analyzing the scanning steady rate curve of the mode,the scanning rate stability characteristics of the system are summarized.Next,the key factors influencing the steady rate performance of the inner and outer gimbals are located separately and the generation mechanism of the outer gimbal′s velocity oscillation is studied by using the descriptive function method.Optimization measures are proposed for the inner and outer gimbals respectively.A torque-balanced dual-motor control is adopted for the outer gimbal and an acceleration loop is added to the speed circuit of the inner gimbal without a current loop.The final experimental verification of the optimisation measures shows that the adjustment time of the internal gimbal is basically unchanged after the acceleration feedback the maximum deviation during speed rotation is reduced from 1.08 V to 1.00 V,and the disturbance isolation capability of the internal gimbal is also improved.With the use of atorque-balanced dual motor control for the outer gimbal,speed oscillations caused by tooth clearance are suppressed and the maximum speed error is reduced from 0.4°/s to 0.2°/s.