精密气浮转台励磁电流矢量控制  

Vector control of excitation current for precision air flotation turntable

作　　者：王福全[1] 周智勇[1] 张军 朱世涛 段黎明[1] Wang Fuquan;Zhou Zhiyong;Zhang Jun;Zhu Shitao;Duan Liming(ICT Research Center,Key Laboratory of Optoelectronic Technology and Systems of Ministry of Education,Chongqing University,Chongqing 400030,China;College of Mechanical Engineering,Chongqing University,Chongqing 400030,China;China Silian Instrument Group Co.,Ltd.,Chongqing 400700,China)

机构地区：[1]重庆大学光电技术及系统教育部重点实验室ICT研究中心,重庆400030 [2]重庆大学机械工程学院,重庆400030 [3]中国四联仪器仪表集团有限公司,重庆400700

出　　处：《仪器仪表学报》2020年第11期66-73,共8页Chinese Journal of Scientific Instrument

基　　金：国家科学仪器设备开发专项(2013YQ030629);重庆大学中央高校基本科研业务费专项(2019CDXYGD0028)资助。

摘　　要：为实现精密气浮转台精准定位和低速平稳运行的同时降低硬件成本,针对精密气浮转台轻载、低摩擦的特点,提出了一种无需电流反馈的励磁电流矢量控制策略。该策略基于矢量控制思想,令d-q坐标系下转矩电流趋于零,转台电机旋转动力主要依靠励磁电流;设计了速度观测器,通过观测转速变化对转矩电流进行力矩补偿,以提高伺服系统动态响应能力和扩大低速控制范围。对比常规三环伺服系统,该策略没有电流闭环回路,无需高精度电流反馈,节约了硬件成本。理论研究表明:励磁电流越大,转台抗扰性越强;实验结果表明:在低成本硬件平台上,力矩补偿后转台运动跟踪误差≤2.87″,均方根误差≤1.51″。该方法能在低成本硬件平台上,实现精密气浮转台定位精度高、速度平稳性好的要求。To achieve precise positioning and low-speed smooth operation of the precision air floatation turntable while reducing hardware costs, an excitation current vector control strategy without current feedback is proposed for the light load and low friction characteristics of the precision air floatation turntable. This strategy is based on the vector control idea. To be specific, the torque current in the d-q coordinate system is approximately equal to zero, and the rotating power of the turntable motor mainly depends on the excitation current. A speed observer is designed to compensate the torque current by observing the speed change. In this way, the dynamic response capability is improved and the low-speed control range of the servo system is expanded. Compared with the conventional three-loop servo system, this strategy does not have a current closed-loop and does not require high-precision current feedback. Therefore, the hardware costs can be saved. Theoretical research shows that the higher the excitation current, the stronger the immunity of the turntable. Experimental results show that on a low-cost hardware platform, the motion tracking error of the turntable after torque compensation is not larger than2.87″, and the root mean square error is not larger than 1.51″. The method can meet the requirements of high positioning accuracy and good speed stability of the precision air float turntable on a low-cost hardware platform.

关 键 词：气浮转台 励磁电流 矢量控制 低速控制 

分 类 号：TH133.3[机械工程—机械制造及自动化] TP312[自动化与计算机技术—计算机软件与理论]