干摩擦对随动系统低速特性影响的分析

The Analysis of the Effects of Dry Friction on Low-Speed Performance of Servo System

本文用状态变量法和分段线性法,通过分析一种典型随动系统的恒速跟踪过程,讨论了干摩擦对系统低速特性的影响,指出了改善低速特性的途径。

How to improve low-speed performance of servo systems is one of the important subjects coufronting system designers. There are many factors affecting low-speed performance, one of which is the static and kinetic dry friction in the actuator. The main affect of dry friction on the motion of a servo system is to ca- use unsteady motion of the drive shaft at low speed. In this paper, response of a typical D. C. servo system with static and kinetic dry friction to ramp input has been analysed by means of piecewise-linear and state-variable methods. The system includes a position feedback, a rate feedback, and a PI cascade compensator. Both eff- ects of static and kinetic dry friction on low-speed performance of servo system and how to modify it is discussed.