削片机进给机构随动系统仿真分析

Imulation Analysis of Servo System for Feeding Mechanism of Chipper

为提高削片机的工作效率,保证作业的安全性,解决随动系统跟踪过程中响应慢、稳定性不足等问题。以削片机进给机构液压随动系统为研究对象,基于工作原理进一步分析系统中双喷嘴挡板二级电液伺服阀和四通阀控非对称液压缸2个主要部件的结构特性,并建立相应的数学模型。根据系统原理框图,推导随动系统的开环传递函数,采用MATLAB仿真软件搭建系统Simulink仿真框图,通过PID控制器校正系统,对比分析校正前后的仿真结果。结果表明,系统截止频率由86. 3 rad/s降为25. 8 rad/s,响应时间由0. 679 s缩短至0. 302 s,幅值裕度提高至为6. 09 dB,校正后系统稳定性增强。

In order to improve work efficiency of chipper,ensure safety of operation and solve problems of slow response and poor stability during tracking process of servo system,we take a servo system of chipper feeding system as the research object.The system consists of two main components:a double nozzle baffle secondary electro-hydraulic servo valve and a four-way valve controlled asymmetric hydraulic cylinder.By analyzing their structural characteristics,we establish a corresponding mathematical model.According to the principle block diagram of the system,an open-loop transfer function is derived,and a system simulation model is established with MATLAB.By adjusting the system with a PID controller,we compare and analyze the simulation results before and after the calibration.The result shows that the cut-off frequency and the response time are reduced,and the stability and the amplitude margin are enhanced after correction.