中草药微波真空连续干燥机控制系统的设计

针对中草药微波真空连续干燥过程复杂,自动化程度要求高的问题,将PLC、触摸屏等自动化及人机工程技术引入到中草药微波真空连续干燥过程中,建立了由PLC、MP277(触摸屏)、物料输送机构(包括进料、出料)、调频器、制冷机组、集水器、真空泵、微波组件、电磁阀、温度传感器、湿度传感器、压力表和重量传感器等组成的中草药微波真空连续干燥控制系统。着重研究了中草药微波真空连续干燥机PLC自动控制系统的结构及原理,进行了PLC、触摸屏及重要传感器的选型,并编制了上位机及下位机控制程序。实际运行结果证实,该系统实现了中草药微波真空连续干燥过程的自动控制,提高了中草药微波真空连续干燥机的可靠性和自动化程度。

Control system for continuous microwave-vacuum drier of Chinese herbal medicine

Aiming at the high level of automation which is needed in the process of the Chinese herbal medicine continuous microwave-vacu- um drying, the PLC, touch panel and other automation and man-machine engineering technology were introduced to the process of the Chi- nese herbal medicine continuous microwave vacuum drying. And the control system for continuous microwave-vacuum drier of the Chinese herbal medicine was designed. This control system was composed of PLC, touch panel, material conveying mechanism, frequency regulator, refrigeration unit, water collector, vacuum pump, microwave unit, electromagnetic valve and a series of sensers. And the structure and prin- ciple of the control system for the Chinese herbal medicine continuous microwave-vacuum drying were studied. At the same time, the type of PLC , touch panel and the important sensers was chosen and the program was designed and tested. The system running results indicate that the Chinese herbal medicine continuous microwave-vacuum dryer is robotized. As a result, the reliability of Chinese herbal medicine dryer is improved.