磁场补偿对LVDT静态特性影响的研究  

Study on Influence of Magnetic Field Compensation on Static Characteristics of LVDT

作　　者：林宪臣 尹明富[1] 孙会来[1] 赵镇宏[1] Lin Xianchen;Yin Mingfu;Sun Huilai;Zhao Zhenhong(College of Mechanical Engineering,Tianjin Polytechnic University,Tianjin 300387,China)

机构地区：[1]天津工业大学机械工程学院,天津300387

出　　处：《机械科学与技术》2019年第5期773-778,共6页Mechanical Science and Technology for Aerospace Engineering

基　　金：天津市科委项目(14JCTPJC00536);天津市高等学校科技发展基金项目(20130402)资助

摘　　要：为改善因内部感应磁场分布不均导致差动变压器式位移传感器(Linear variable differential transformer, LVDT)线性度差、灵敏度低的问题,提出一种磁场补偿法。在LVDT次级线圈远端添加两个关于初级线圈对称的导磁环,同时将可动铁芯的末端设计成具有一定锥度的形式,导磁环和铁芯均为软磁材料。利用有限元方法在Maxwell中建立LVDT模型,模块化后导入Simplorer中,在Simplorer中连接外部激励电路进行瞬态磁场的计算机联合仿真。瞬态分析结果表明:经过磁场补偿,LVDT的线性度和灵敏度得到显著提高,线性度从1.79%提高到0.5%,灵敏度提高了17.9 mV/mm,通过搭建实验平台,验证了方案的可行性。A magnetic field compensation method is proposed to improve the linearity difference and low sensitivity of the linear variable differential transformer sensor(LVDT)due to the uneven distribution of the internal induced magnetic field.Adding two magnetic flux rings about the primary coil symmetry at the distal end of the LVDT secondary coil,and designing the end of the movable iron core into a form with a certain taper,the magnetic flux ring and the iron core are soft magnetic materials.The model of improved LVDT is established in Maxwell using finite element method,modularized and imported into Simplorer.The external excitation circuit is connected in Simplorer for joint computer simulation of transient magnetic field.The transient analysis results show that the linearity and sensitivity of LVDT are significantly improved by magnetic field compensation,the linearity is improved from 1.79%to 0.5%,and the sensitivity is improved by 17.9 mV/mm.Finally,the experimental platform was built to verify the feasibility of the scheme.

关 键 词：磁场补偿 线性度 灵敏度 导磁环 锥形末端 

分 类 号：TP212.9[自动化与计算机技术—检测技术与自动化装置]