无源线圈在电磁感应溶液测量中的增强效应

将一只由线圈与电容元件共同组成的无源线圈放置于探测线圈与待测电解质溶液组成的测量系统中,借助无源线圈与两者之间的电磁感应耦合,可在谐振频率点附近提高测量系统的探测性能。以塑料容器内0~5%质量分数浓度的Na Cl溶液为探测目标,对无源线圈置于目标溶液前侧及背侧两种情况下的阻抗谱进行了实验分析。结果表明,相同探测距离下,介入无源线圈的测量系统对电解质溶液的浓度表现出更高的灵敏度。当目标溶液位于探测线圈敏感距离之外时,介入无源线圈后依然可实现有效的溶液浓度测量。无源线圈的这种增强效应可提升电磁感应系统的有效探测距离,实现电解质溶液或生物组织等低电导率物质的远距离非接触测量。     

线圈绕制技术

在生产实践中,往往要根据阻值要求绕制线圈,如电磁计数器的线圈、继电器的线圈等。在检查线圈时,也是根据技术条件中规定的电阻值来衡量线圈是否符合要求,对于外界温度的变化确不给预考虑,     

面向机载地磁测量的磁干扰补偿技术

针对机载地磁测量易受发动机干扰的问题,提出将干扰分为动态、静态2种情况处理.首先进行静态补偿,然后针对匀速运动的机载地磁测量,提出了等效电流补偿方法,最后引入卡尔曼数字滤波,消除发动机动态运转产生的高频磁干扰.上述方法能在电机的运行过程中测量出相对实时的、准确的地磁值,减小了电机的磁场干扰,具有很强的实用价值.     

基于电磁感应原理测量物体角速度

提出了利用电磁感应原理测量旋转物体角速度的方法.首先利用运动转化机构,将物体的旋转运动转化为直线往复运动;利用磁铁切割线圈发电性质,使线圈产生周期性变化的电流;利用示波器显示电流随时间变化曲线,通过分析该曲线的极值特征得到随时间变化旋转角度的数据;最后利用逐差法对数据进行处理,得旋转物体角速度随时间变化曲线.     

离散电流对精密线圈磁场影响的研究

研究了通常用电流片模型来近似计算线圈磁场时被忽略的由于导线电流的离散而引起的附加磁场的变化规律,指出此种附加磁场会随着离开导线距离的增加而迅速衰减.此结论可用于指导精度要求较高的线圈磁场系统的设计,如用于质子回旋磁比γp′测量的高精度亥姆霍兹线圈的设计和用于普朗克常数h测量的焦耳天平系统中的精密互感线圈的设计等.     

大型电机故障线圈的修复

高压交流电动机在运行过程中所发生的故障多在电气方面,而又以定子线故障为主,如线圈绝缘因电击穿而接地并导致某个线圈或其中的一些线匝被电弧烧断。处理此类故障的办法通常是更换线圈,既增加费用,又耗时过多,特别是在没有备用线圈时更是如此。     

谈提高电度表电压线圈绕制技术

谈提高电度表电压线圈绕制技术杭州电子仪表工业公司陈亚璜一、引言电度表是电工仪表中量大面广的电能计量仪表．全国１９９４年单、三相电度表的生产总量在３０００万台以上．随着家用电器在居民中的普及使用，生活用电量大幅度增加。供电部门对电度表的电流过载、计量精...     

电磁阀线圈的改进

港用翻车机的液压系统中有很多电磁阀,在实际应用中经常出现电磁阀线圈正极腐蚀断路的情况。为此设计了一种电磁阀线圈,降低故障率,节约备件成本。     

Analysis of the induction heating for moving inductor coil

Induction heating is a process that is accompanied with magnetic and thermal situation. This paper presents a simulation of a magneto-thermal coupled problem of an induction heating process for moving inductor coil. In the magnetic and thermal analyses, temperature-dependent magnetic and thermal material properties were considered. As the inductor coil moves in the process, solution domains corresponding to inductor changes into those of the air, and the solution domains of air change into those of the inductor. For these reasons, modeling of induction heating process is very difficult with general purpose commercial programs. In this paper, induction heating process for moving coil was simulated with the concept of traveling the position of the heating planes. Finite element program was developed and finite element results were compared with the experimental results.     

DC operation analysis of induction coil fluxmeters with integrating amplifiers

Modern fluxmeter operation is based on electronic integration. A system consisting of an induction coil and an integrator can be used to measure incremental changes in the flux linkages associated with the induction coil. A rigorous proof is presented that the inductance and self-capacitance of the induction coil, as well as the parasitics of the load resistor, do not influence the integrator output in measurement of incremental flux linkages using DC operation of the fluxmeter. The theoretical analysis is confirmed by experimental results.     

感应加热线圈参数对被试件温度场的影响分析

针对感应线圈参数对感应加热温度场的影响问题,以ANSYS软件为工具,采用磁热耦合分析的方法,对不同参数水平条件下的电磁感应加热过程进行了有限元计算。运用仿真结果对比分析的方法,研究了感应线圈形状、与加热面间的距离、线圈铜管宽度以及铜管间距对感应加热温度场的影响规律。并以平板被试件为对象,设计了平板感应加热测温试验,对仿真结果进行了试验验证。研究结果表明,感应加热温度场高温区域的形状与线圈形状相似;线圈与加热面之间距离越小,加热温度幅值越大,但对温度分布基本无影响;铜管越细或铜管间距越小,加热最高温度越高,且高温区域向平板边缘移动。     

动力调谐挠性陀螺仪、光纤陀螺仪的测试及分析

动力调谐陀螺仪和光纤陀螺仪是目前应用非常广泛的陀螺仪,对于它们的测试显得非常重要,本文对动力调谐挠性陀螺仪及光纤陀螺仪的测试内容、测试方法以及相关的误差分析进行介绍,并简单介绍当前的测试状况。     

可控硅中频透热炉负载感应线圈的改进

介绍一种全新的可控硅中频炉负载匹配的方法。     

Artificial neural network prediction of weld distortion rectification using a travelling induction coil

Field activated sintering is receiving a growing attention as an alternative to classical sintering for its unique ability to realize high level of densification at low temperatures and using short processing times. This technique, however, is characterized by the presence of complex temperature and stress distributions and, as a result, microstructural non-uniformities may be produced in the samples. These temperature non-homogeneities depend on a large number of experimental parameters, such as die geometry, heating rate, material properties, sintering temperature, etc. In this paper, the various experimental parameters are systematically analyzed in order to evidence their role in determining the temperature distribution. Methods to control or remove temperature inhomogeneities will be discussed, particularly in the case of large samples.     

航空光电成像平台角位置陀螺和角速率陀螺的稳定效果分析

研究了角速率陀螺稳定平台在目标跟踪时瞄准线始终围绕视场中心做约2 Hz晃动的现象,理论推导及数值分析认为引起这一现象的原因与光电稳定平台的静态力矩刚度为0、隔离度仅为71.4 dB有关。采用基于角位置陀螺的光电稳定平台,其静态力矩刚度为1 732 Nm,隔离度提高到126 dB,可以有效地消除这种晃动。     

Study on offset measurement of underwater high-speed moving body based on single induction coil

In this paper, a new offset measurement method for underwater rod-shaped high-speed moving body has been presented. Based on the principle of electromagnetic induction, the offset test reference model of the underwater detection sensor was developed to analyze the influence of offset on the induced electromotive force of the underwater inductive sensor. Moreover, simulations by MATLAB was carried out to analyze the influence of offset on the induced electromotive force of the measurement system while underwater high-speed moving body passing through the induction coil in different direction. Two important factors correlated closely with the offset were obtained, which are the amplitude and the width between the adjacent peak and peak-valley of the induced electromotive force caused by the high-speed moving body through the induction coil. And most importantly, an offset measurement experiment of underwater high-speed moving body based on single induction coil was conducted to validate the simulation results obtained above. By comparing the experiment results with the simulation data, the new offset measurement method put forward in this work was proved to be feasible.     

基于平面地磁感应线圈测量高速自旋弹丸转速的方法

针对高自旋弹丸的转速测试问题,推导了在三维转动中地磁感应线圈的输出公式,并在合理的假设下对高自旋弹丸的输出信号进行了简化,给出了输出信号的半周期确定方法及基于相位信息的转速测试原理。测试结果表明,利用本文方法得到的转速曲线和遥测结果是一致的。