电容式土壤水分检测多参数校正方法的研究  

Research on Multi-parameter Calibration Method for Capacitive Soil Moisture Detection

作　　者：顾惠南 杨雷 邓霄 吕华芳[3] 宋志强 潘丽鹏 张丽 崔丽琴 GU Hui nan;YANG Lei;DENG Xiao;LYU Hua fang;SONG Zhi qiang;PAN Li peng;ZHANG Li;CUI Li qin(College of Physics and Optoelectronics,Taiyuan University of Technology,Taiyuan 030024,China;Taiyuan University of Technology,China Ministry of Education Key Lab of Advanced Transducers and Intelligent Control System,Taiyuan 030024,China;State Key Laboratory of Hydroscience and Engineering,Department of Hydraulic Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]太原理工大学物理与光电工程学院,山西太原030024 [2]太原理工大学,新型传感器与智能控制教育部与山西省重点实验室,山西太原030024 [3]清华大学水利水电工程系,水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《仪表技术与传感器》2020年第4期117-123,共7页Instrument Technique and Sensor

基　　金：国家重点研发计划项目(2016YFC0402900);国家自然科学基金项目(51809147,51641904,51809190,51205273);山西省青年科技研究基金项目(2015021097);国家留学基金项目(201508140062);山西省研究生教育创新项目(2018SY020)。

摘　　要：土壤水分含量是现代农业灌溉的重要测量物理量。目前常用的土壤水分传感器大多采用高频检测技术,成本较高,无法推广应用。文中基于低频电容式土壤水分传感原理,引入温度、电导率、电容参数,建立土壤水分测量数学模型,对比了在4种不同土样情况下,温度对电容值、电导率的影响,以黄土为例对实测数据拟合及公式推导,将得到的水分测量关系进行多次验证,测试结果表明,利用该校正方法的传感器的测量最大误差小于3.0%,平均绝对误差小于2.0%,能够满足农业灌溉对土壤水分检测的精度要求。Soil moisture content is an important measured physical quantity for modern agricultural irrigation.At present,most soil moisture sensors use high-frequency detection technology.This method can result in high costs and cannot be widely promoted.This paper introduced temperature,conductivity and capacitance parameters to establish a mathematical model of soil moisture measurement based on the low-frequency capacitive soil moisture sensing.The influence of temperature on capacitance value and conductivity was compared under four different soil samples.The loess was taken as an example to fit the measured data and formula,and the obtained water measurement relationship was verified several times.The test results show that the maximum error of the measurement using the calibration method is less than 3.0%,and the average absolute error is less than 2.0%,which can meet the accuracy requirements of agricultural irrigation for soil moisture detection.

关 键 词：土壤水分 低频 电容式 温度 电导率 

分 类 号：TP212.6[自动化与计算机技术—检测技术与自动化装置] S152.7[自动化与计算机技术—控制科学与工程]