微纳加工中高精度环境温度控制系统的设计

摘要

统计表明,在微纳加工领域中,由于热变形引起的误差占总误差的40％ ～ 70％,已经成为制约微纳加工发展的主要因素之一.本系统采用基于PLC的增量式数字PID控制方法,实现对微纳加工控制过程中环境温度的高精度控制.利用LabVIEW软件编程灵活的特点,设计控制系统界面,通过RS485接口实现计算机对PLC的实时监控,保存测量数据,实时进行精度分析.经长时稳定试验,本系统可以实现±0.05℃/24 h的控制精度(24 h内温度波动不超过±0.05℃),满足高精度加工系统的温度控制需求.%Statistics show that in the field of micro-nano processing,the error caused by the thermal deformation takes up from 40％ to 70％ of the total error,which has become one of the main factors of restricting the development of micro-nano processing.An incremental PID control algorithm based on PLC is used to achieve highprecision control of ambient temperature in the process of micro-nano control,and features of LabVIEW's flexible programming is taken full advantage of to design the interface of system.Meanwhile,through the RS485 interface,the computer real-time monitoring on the PLC is achieved and the measurement data are stored,then the precision of these data is analyzed.After a long time stability test,the system can achieve the precision of ± 0.05 C per 24 h,which meets the requirements of this system for high-precision temperature control.