摘要
【目的】为优化热泵粮食干燥机的干燥工艺,实现对热泵粮食干燥机干燥过程的自动化控制,研制了空气源热泵粮食干燥机信息采集与自动控制系统。【方法】该系统以4级联合而成的空气源热泵作为热源,通过改变热泵机组的启停组合调节送风温度,以江苏天禹生产的型号为5HXG-120循环式谷物干燥机为机体,其内部自上而下分别为缓苏段、干燥段、冷却段和排粮段,由数据采集模块、控制模块和报警系统等组成,采集卡采集热风温湿度、环境温湿度、粮食温度等数据通过PCI总线传送到型号为IPC-610的工控机,以LabVIEW软件技术开发上位机,以西门子S7-200系列可编程逻辑控制器(PLC)作为下位机,进行系统硬件电路的搭建与软件的设计,从而实现对试验过程中各数据的实时监测和对空气源热泵以及粮食干燥机的控制。【结果】在环境温度为16.6℃时,以55℃为目标热风温度,当系统趋于稳定时,温度控制在53.9~57.2℃,符合GB/T 16714中控制温度在±2.5℃之内的控制要求。稻谷的含水率由22.9%降低至14.9%,干燥前期由于谷物中含水率较高,降水速率较明显,干燥后期谷物中自由水分减少,降水速率降低,整个干燥过程的平均降水速度为每小时0.69%,符合粮食干燥的规律。【结论】该系统能够对温度、湿度、水分值、电压、电流等试验数据进行显示与存储,实现空气源热泵粮食干燥机进料、循环、干燥和排粮4个工艺过程,干燥后的稻谷水分较均匀,品质良好,达到预期的干燥效果,与燃煤热风炉相比,能够大大节省成本,同时,该系统的研制为不同环境温度下控制策略的制定提供理论基础。
[Objective]In order to optimize the drying process of the heat pump grain dryer and realize the automatic control of the drying process of the heat pump grain dryer,an information collection and automatic control system of air source heat pump grain dryers was developed.[Method]A 4-stage combined air source heat pump was used as the heat source,the air supply temperature was adjusted by changing the on-off combination of the heat pump unit.The 5HXG-120 circulating grain dryer produced by Jiangsu Tianyu was used as the body,which is composed of a tempering section,a drying section,a cooling section and a grain discharge section from top to bottom.The system consists of a data acquisition module,a control module and an alarm system.The collection card collects the data of hot air temperature and humidity,ambient temperature and humidity and grain temperature,and transmits the data to the IPC-610 industrial computer through the PCI bus.The host computer was developed with LabVIEW software technology,and the Siemens S7-200 series programmable logic controller(PLC)was used as the slave computer to build the hardware circuit of the system and design the software,in order to realize the real-time data collection and controlling.[Result]The tests showed that when the ambient temperature was 16.6℃,the target hot air temperature was 55℃,the system was in a stable operation,and the temperature was controlled within 53.9℃to 57.2℃,which met the control requirements of GB/T 16714 to control the temperature within±2.5℃,the moisture content of grain was reduced from 22.9%to 14.9%.In the early drying stage,since the moisture content in the grain was high,and the dehydration rate was fast.In the later stage of drying,the free moisture in the grain decreased and the dehydration rate decreased.The average dehydration rate during the entire drying process was 0.69%per hour,which was in line with the law of grain drying.[Conclusion]The system could display and store test data such as temperature,humidity,moisture value,volt
作者
张华希
闫一哲
李和清
朱伟
陈坤杰
刘德营
ZHANG Huaxi;YAN Yizhe;LI Heqing;ZHU Wei;CHEN Kunjie;LIU Deying(College of Engineering,Nanjing Agricultural University,Nanjing 210031,China)
出处
《江西农业大学学报》
CAS
CSCD
北大核心
2022年第1期205-211,共7页
Acta Agriculturae Universitatis Jiangxiensis
基金
江苏省重点研发计划项目(BE2021305)
江苏省农业科技自主创新资金子项目(CX(17)1002-05)。
关键词
空气源热泵
粮食干燥机
数据采集
自动控制
air source heat pump
grain dryer
data collection
automatic control
