基于热脉冲精密土壤水分测试仪的研究与设计  

Design of precision soil moisture tester based on thermal pulse

作　　者：魏丽君[1] WEI Lijun(Hunan Railway Professional Technology College, Hunan Zhuzhou 412001, China)

机构地区：[1]湖南铁道职业技术学院,湖南株洲412001

出　　处：《工业仪表与自动化装置》2022年第2期3-7,31,共6页Industrial Instrumentation & Automation

基　　金：湖南省教育厅科学研究青年项目(19B379)。

摘　　要：针对土壤水分很难连续准确测量以及测试装置很难在深埋处进行测量的问题,开发一款热脉冲精密土壤水分测试装置。该装置以STM32为硬件开发平台,辅助HS3001温湿度传感器和PTC加热模块组成热脉冲测含水量模块,通过施加短时低热量热脉冲,使得被测土壤先升温再降温,由测试装置定时测量土壤温度的变化值,最后基于理想半无限空间热脉冲传导理论,计算出土壤体积含水量。该装置利用热脉冲可以间接测量土壤体积含水量,热脉冲时间控制在1~2 min,测量周期约300 s,具有短时连续监测的优势;同时在非加热模式下,可以直接获取土壤温湿度,在降雨入渗和水位变化时可以直接监测湿度变化;此外加热模块还可以为温湿度传感器升温除湿,以增强深埋土壤高湿度环境下长期工作性能。In view of the problem that it is difficult to continuously and accurately measure soil moisture and the test device is difficult to measure soil moisture in deep buried place.A thermal pulse precision soil moisture test device is developed.The device uses STM32 as the hardware development platform,assisted by HS3001 temperature and humidity sensor and PTC heating module to form a thermal pulse water content measurement module.By applying short-time low heat thermal pulse,the measured soil is heated first based on the theory of half space heat conduction,the ideal value of soil moisture was measured and calculated.The device can indirectly measure the soil volume water content by using the thermal pulse,the thermal pulse time is controlled in 1~2 min,and the measurement cycle is about 300 s,which has the advantage of short-term continuous monitoring.At the same time,in the non heating mode,the soil temperature and humidity can be directly obtained,and the humidity change can be directly monitored when the rainfall infiltration and water level change.In addition,the heating module can also heat and dehumidify the temperature and humidity sensor in order to enhance the long-term performance of deep buried soil under high humidity environment.

关 键 词：温湿度传感器 热脉冲 半无限空间热脉冲传导 PTC加热 土壤水分测试 

分 类 号：TP334.3[自动化与计算机技术—计算机系统结构]