基于边缘电场效应的双线制电容式水位传感器  

Two-wire Capacitive Water Level Sensor Based on Edge Effect of Electric Field

作　　者：赵凯[1,2] 

机构地区：[1]山西省水文水资源勘测局,山西太原030024 [2]忻州市水文水资源勘测分局,山西忻州034000

出　　处：《数学的实践与认识》2017年第22期100-105,共6页Mathematics in Practice and Theory

基　　金：国家自然科学基金(51404165);山西省自然科学基金(2012021013-2)

摘　　要：研究了一种基于边缘电场效应的双线制电容式水位传感器及其测量电路的软硬件设计.传感器利用一根双芯电线作为敏感单元,能够将水位的高低线性转换为电容量的变化.双芯电线内的两个铜芯分别作为电容式传感器的两个电极.待测的水被绝缘皮隔离在双芯电线的周围.由于两铜芯间的边缘电场的存在,水位的变化会影响两铜芯之间的电容量,因此水位值可通过测量该电容量计算出来.利用测量电路对传感器的测量结果表明:传感器的电容量随水位线性变化,精度为1mm.水位上升时,传感器反应非常灵敏.但水位下降时,传感器的灵敏度略有迟缓.当水位在10秒内从0.9米快速下降到零水位,传感器的响应时间为1分钟.This paper studies a two-wire capacitive water level sensor based on edge effect of electric field,the hardware and software design of the measurement circuit.The sensor uses a double core wire as sensitive unit and has the ability to change the water level to capacitance.Two copper cores inside the wire are respectively as two electrode of capacitive sensor.The water measured is isolated around the wire by insulation skin.As a result of the edge electric field between two copper cores,the change of water level can affect the capacitance between two copper cores.Therefore,the value of water level can be calculated by the capacitance.The measurement results used by the measurement circuit show that the capacitance changes linearly with water level with 1mm accuracy.But when the water level drops,the sensitivity of sensor is not good.The response time of sensor is one minute as the water level drops quickly from 0.9 meter to zero in ten seconds.

关 键 词：边缘电场 电容 水位 传感器 双芯电线 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]