热泵式低温循环谷物干燥机控制系统设计与试验  

Design and Experiment of Heat Pump Low-temperature Circulating Grain Dryer Control System

作　　者：陈坤杰[1] 左毅 李和清 戚超 刘浩鲁 贲宗友 CHEN Kunjie;ZUO Yi;LI Heqing;QI Chao;LIU Haolu;BEN Zongyou(College of Engineering,Nanjing Agricultural University,Nanjing 210031,China;Nanjing Institute of Agricultural Mechanization,Ministry of Agriculture and Rural Affairs,Nanjing 210014,China)

机构地区：[1]南京农业大学工学院,南京210031 [2]农业农村部南京农业机械化研究所,南京210014

出　　处：《农业机械学报》2021年第5期316-323,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：江苏省农业科技自主创新资金子项目(CX(17)100205)。

摘　　要：针对以空气源热泵为热源系统的低温循环谷物干燥机存在的一体化控制程度不足问题,设计了一种热泵式低温循环谷物干燥机控制系统。为实现低温循环谷物干燥机和热泵系统的一体化控制,利用可编程逻辑控制器(PLC)技术进行硬件电路设计和软件设计,系统实现了谷物干燥过程的自动和手动等多模式控制,并支持干燥参数的人工调节和设置、谷物含水率及干燥温度的实时监控等功能。试验表明,干燥机在不同模式下均工作正常;所开发的逻辑控制系统具有自动化程度高、稳定性好、安全性高等优势。稻谷干燥试验表明,在不同环境温度下,热泵热风温度平均误差为0.95℃,标准差为0.93℃,系统具有较好的控制精度与稳定性,粮食温度稳定在33℃左右,满足低温循环式谷物干燥机的作业要求。A heat pump low-temperature circulating grain dryer control system was designed for the low-temperature circulating grain dryer using air source heat pump as the heat source.A multi-mode soft logic system was employed to control the low-temperature circulating grain dryer and heat pump system.In the hierarchical system,the PLC was used as the control core and touch screen as the man-machine interface,programming through the sequential function chart(SFC)and ladder diagram,which guaranteed the multi-mode operation of heat pump low-temperature circulation grain dryer and supported manual adjustment and setting of drying parameters,real-time monitoring of grain moisture content and drying temperature and other functions.The experiments validated the operation of the dryer in manual mode,automatic mode and timing mode.The designed logic control system had advantages of high degree of automation,good stability and high safety and so on.Additionally,experiment results on the control of the drying temperature showed that the mean error of the heat pump outlet temperature was 0.95℃and the standard deviation was 0.93℃at different ambient temperatures,which meant the control system had high accuracy and stability.The grain temperature was stable at about 33℃,which satisfied the operating requirements of the low-temperature circulating grain dryer.

关 键 词：谷物干燥机 空气源热泵 温度控制系统 可编程逻辑控制器 触摸屏 

分 类 号：S226.6[农业科学—农业机械化工程] TP23[农业科学—农业工程]