低速下机床进给伺服系统稳定性研究

PDF(1975 KB)

振动与冲击 ›› 2010, Vol. 29 ›› Issue (5) : 187-190,.

论文

低速下机床进给伺服系统稳定性研究

刘丽兰;刘宏昭;吴子英;原大宁

作者信息 +

Research on stability of the feed servo system of machine toolswith low feed velocity

Liu Lilan;Liu Hongzhao;Wuziying;Yuandaning

Author information +

文章历史 +

摘要

以PID控制的数控机床进给伺服系统为研究对象，研究了低速进给时非线性摩擦对系统的稳定性的影响。采用新的连续摩擦模型，建立了含非线性摩擦的系统单自由度等效模型，同时也计入了负载干扰的影响。基于Taylor级数展开，将非线性滑动摩擦线性化，给出了系统稳定性判别条件的解析表达式。该判别条件可以用来确定PID控制参数以避免系统不稳定。仿真和实验均验证了判别条件的有效性，为预测和消减低速进给时摩擦引起的爬行现象提供了一种简单有效的方法。

Abstract

A type of PID control feed servo system of CNC machine tools is considered. The effects of the nonlinear friction on the stability of the system are investigated. A SDOF equivalent model of the system with nonlinear friction is established by adopting a new continuous friction model. At the same time, the load disturbance is also considered. Based on Taylor series expansion, the nonlinear friction model in the slip region is linearized. And thus, the analytic expression of the system stability criterion is given. It can be applied to determine PID control parameters to avoid instability. Both Simulation and experiment demonstrate that the proposed stability criterion is effective. The present analysis provides a simple and effective method for the prediction and reduction of stick slip behavior, which is induced by friction under low velocity feeding.

导出引用

刘丽兰;刘宏昭;吴子英;原大宁. 低速下机床进给伺服系统稳定性研究 [J]. 振动与冲击, 2010, 29(5): 187-190,

Liu Lilan;Liu Hongzhao;Wuziying;Yuandaning. Research on stability of the feed servo system of machine toolswith low feed velocity [J]. Journal of Vibration and Shock, 2010, 29(5): 187-190,