温度传感器动态校准的研究

本文综述了传感器动态校准的现状,包括它的概念、特点、数据处理方法等,特别是针对温度传感器动态校准的方法进行了研究,给出院 校准装置的选择和评安结果的一些方法。     

瞬态表面温度自动动态校准系统

文中介绍自动动态校准系统的结构和原理及软件设计,该系统可实现对表面温度传感器动态特性的自动校准.     

温度传感器热惯性对动态测量误差的影响

建立了温度传感器的数学模型,指出由于温度传感器存在热惯性会造成动态测量误差,提出了减小误差的措施。     

液氮中微秒级脉冲下的沿面闪络特性

液氮环境中绝缘材料的沿面闪络对超导电力设备外绝缘设计至关重要,为了揭示液氮环境中沿面闪络的发展过程,并研究有效提高超导电力设备外绝缘爬电距离的方法,通过实验对不同直径的圆柱形、不同倾角的圆台形聚四氟乙烯试品在液氮中微妙级负脉冲电压作用下的沿面闪络电压进行了测量,结果发现圆柱形试品随直径增加,沿面闪络电压下降;圆台形试品在θ=-45°时闪络电压最高,θ=0°时闪络电压最低.通过与真空、绝缘油中沿面闪络的数据比较以及仿真计算,认为液氮中的沿面闪络与变压器和绝缘油中有相似的闪络机制,沿面闪络是在气化的闪络通道内完成的.实验的结果也为超导电力设备外绝缘设计提供了有益的方法.     

电力牵引传动系统微秒级硬件在环实时仿真

为满足电力牵引传动系统高速实时仿真的需求,分析了交直交牵引传动系统的结构及其原理,建立了现场可编程门阵列硬件在环(HIL)仿真模型,其中包含单相脉冲整流器、中间直流回路、三相两电平逆变器以及异步电机四部分。对于含有开关器件的结构——逆变器和整流器,分别推导出它们不同状态下各自开关函数的逻辑表达式,考虑了变流器电流过零点时的换流情况。采用状态方程及矩阵方程分别对变流器以及异步电机进行建模,并将数学模型集成在FPGA中加以实现,在RT-LAB实时仿真器上进行HIL仿真,验证了仿真平台的正确性。由于采用FPGA模拟牵引传动系统,充分发挥了其善于并行计算的特性,大幅缩短了仿真的步长,突破了中央处理器速度限制,实现了微秒级系统模型实时仿真,提高了HIL仿真系统的响应速度以及准确度。     

一种多维动态力传感器校准系统研究

针对高精度多维动态力传感器测量的要求,设计了一种多维动态力传感器校准系统。系统以偏心质量旋转产生的离心力作为校准依据,同时对多维力传感器2个方向的力进行校准。对校准系统的精度特性进行了理论分析,误差分析的结果说明了系统的可靠性。利用LabVIEW编制动态校准系统软件,实现了对多路信号的实时连续滤波。对某型六维力传感器进行了校准实验,通过测量值与理论值的对比,得到待校准传感器的校准系数,验证了动态校准系统的可行性。     

克服温度传感器测量滞后误差的动态补偿算法

由于温度传感器的测量滞后,导致温度控制系统中的实际被控温度存在较大超调。本文提出了一种基于遗传神经元网络补偿的动态测量方法,该方法利用遗传神经元网络的快速逼近能力,建立传感器的动态逆模型,实现对传感器动态测量的补偿。此方法设计的动态补偿器具有不依赖传感器模型,鲁棒性强等特点,检测信号经补偿计算后,能够克服传感器的测量滞后,实验证明了该方法的有效性。     

重复频率微秒脉冲电压下多间隙气体开关级间绝缘子沿面闪络特性

多级间隙气体开关是高功率微波装置中的关键器件,其中级间绝缘子沿面绝缘强度是影响开关稳定性和寿命的关键因素之一。文中模拟级间绝缘子实际工作条件,对平行平板电极中的圆柱形绝缘子试样施加重频微秒脉冲电压,开展闪络电压、闪络时延以及沿面寿命的实验研究。结果表明:气/固介电常数差异加剧电场畸变,使得闪络电压随着绝缘子材料介电常数增大而降低,SF₆中不同材料闪络电压的差异小于空气中;由于累积效应,闪络电压和闪络时延随着重复频率增加整体呈下降趋势;相同欠压比下,绝缘子沿面寿命随着气压升高而增长,SF₆中沿面寿命高空气中一个数量级,介电常数较大的材料具有更优异的沿面寿命;SF₆与空气闪络路径的差异导致SF₆中沿面闪络特性具有与空气中不同的特点,闪络放电分散性低于空气中,重频脉冲作用下材料表面光电发射作用更为显著,连续闪络中劣化猝发等。该研究为级间绝缘子沿面绝缘设计和绝缘材料筛选提供了理论依据。     

基于斩波和动态元件匹配的CMOS集成温度传感器的设计

利用CMOS工艺下衬底型双极晶体管的温度特性,设计了一种精度较高的温度传感器。斩波技术和动态元件匹配技术的应用很好的提高了温度传感器的精度。文章对斩波和动态元件匹配技术进行了详细的分析。并采用HYNIX0．5μm混合信号工艺进行仿真和流片,仿真结果显示,该温度传感器精度为±0．4℃,工作的温度的范围-40℃～＋100℃。多个芯片实测结果表明：温度传感器精度为±0．7℃,功耗0．35mW,芯片面积是889μm×620μm。芯片输出为模拟电压信号,便于后续电路进行采集。该温度传感器已经成功用在消费类电子产品中。     

高性能AX8000多轴伺服系统最大限度地提高设备吞吐量 无菌瓶运输扫描时间缩短至微秒级

总部位于丹麦锡尔克堡的SVM Automatik A/S公司在其为制药行业开发的运输设备NESTOR的设计中采用了高性能的AX8000多轴伺服系统。在进行质量管理时,该设备仅需几微秒时间即可完成无菌玻璃容器的质量控制工作。此外,它可以非常灵活、快速地进行转换,并且比以前的型号更容易编程。     

地温传感器现场校准多通道采集系统设计

为提高地温传感器现场校准效率,充分发挥便携式超级干体/液体槽多用温度校验炉的功能,设计一种基于ATmega16L单片机与CMOS 16通道多路复用器的多通道采集系统。该系统具有人机交互界面,能够进行单通道和多通道扫描。系统中微处理器能够根据设置的扫描通道数和扫描间隔控制模拟开关进行通道切换扫描,将采集到的温度值输送到温度校验炉的显示屏上,实现与温度校验炉的实时通信。测试结果表明：该系统能够自动扫描显示各通道传感器的测量值,实现数据读取的自动化,具有较高的实用性与推广价值。     

Arc temperature measurement with microsecond spectroscopic measurement

The quality of electric power caused by frequency fluctuation and voltage rise will be degraded because of the lightning surge and the mass introduction of distributed power. Thus, it is necessary to improve the performance of gas circuit breaker in order to maintain the stable supply of electric power. It has been reported that the arc conductance is calculated as the index of the current interruption in numerical analysis. However, few report have the measured value in the current interruption. This is because that the current interruption is the steep phenomenon of micro seconds range. Thus, it is necessary to establish the time-high precision and noncontact measurement method. In this paper, the arc temperature is measured near current zero using the microsecond spectroscopic measurement. As a result, the microsecond spectroscopic measurement which combines the conventional spectroscope and the high speed video camera is 200 times faster than the measurement of conventional spectroscope. For this reason, the microsecond spectroscopic measurement is possible with the high speed video camera. Therefore, it is possible to measure the arc temperature with decreasing the current using the microsecond spectroscope.     

柔性力敏传感器的快速标定方法的研究

由于柔性力敏传感器阵列敏感点多,每个敏感点输出值差异大,为了解决传感器标定复杂的问题,给出了一种基于BP神经网络建立一个标定分类模型的快速标定方法,运用面积法给传感器阵列上的敏感点标定曲线分类,使用BP神经网络训练出分类模型,再运用最小二乘法拟合出每一类的标定曲线。通过验证样本检查了分类模型的分类正确率达到98%以上,实验验证了算法的标定结果准确性,标定时间小于1 s。实验结果表明,该方法对大面积柔性力敏传感器的标定效果理想,标定速度快,可以用来做柔性力敏传感器的标定。     

力传感器关键性能参数自动标定系统

针对力传感器的线性度、重复性、迟滞等关键性能参数的标定要求,提出了将虚拟仪器技术与数据采集技术运用于力传感器自动连续标定的方案,系统由力传感器、信号调理器、数据采集卡、力加载装置、上位计算机、系统软件6部分组成.开发的系统软件能够实现连续的数据采集、数据分析、数据显示.力传感器自动连续标定按照JJG144-2007《标准测力仪》计量校准,结果表明本装置的测力精度为1级.本项目的成功实施为力传感器的动态连续标定提供了新的技术手段.     

电能表检验技术的进步

回顾我国电能表检验技术进步的历程,介绍了当前电能表检验装置产品整机性能及其主要组件——标准电能表、程控功率源和操作软件的技术水平,并指出其发展趋势。     

船载雷达角度零值动态标定方法研究

针对船载雷达海上动态环境下角度标校的难题,介绍了船载雷达角度零值动态标定新方法——星体测量法,该方法以高精度的经纬仪为基准,通过雷达与经纬仪联合测量恒星,在同一坐标系下进行数据处理,得到角度零值.同时,本文对各种标定方法的优劣进行研究分析,通过试验验证,与传统坞内标定等方法相比,动态标定新方法优势显著,提高了测角精度.     

High-accuracy source-independent radiometric calibration with low complexity for infrared photonic sensors

Radiometric calibration (RC) is an essential solution to guarantee measurements from infrared photonic sensors with certain accuracy, the main task of which is ...     

Cantilever beam temperature sensors for biological applications

This review presents two types of cantilever beams employed as highly sensitive temperature sensors. One type is fabricated from composite materials and is operated in the deflection mode. The second type, used as a temperature sensor and presented in this review, is a resonant cantilever beam. The materials used for the fabrication of the bimaterial cantilever beam are silicon or silicon nitride and thin metallic films such as gold or aluminum. When the temperature changes, the different coefficients of thermal expansion of the metal and silicon cause the sensor to deflect. Considering the models of temperature measurement for biological cells, the heat should be applied locally at the tip of the cantilever beam. Formulas for the calculation of the deflection as a function of incident power applied at the free end of the cantilever beam operated in a liquid are presented in this review. The natural convective heat transfer coefficient was estimated by using the mathematical model and experimental values. For biological applications, the cantilever beam temperature sensor was operated in a liquid, and the heat transfer coefficients were between 381 and 642 W/m²K when the temperature applied to the cantilever's free end varied from 28 to 71.8 °C. The resonant cantilever beam was also demonstrated as a sensitive temperature sensor for biological applications. As a thermogenic sample, brown fat cells (BFCs ), which are related to metabolic heat production, are employed. The working principle of the resonator cantilever beam temperature sensor is based on the shift in resonant frequency in response to temperature changes. The resonant frequency and the temperature coefficient were 960 kHz and 22.0 ppm/K, respectively. The measurements were performed by stimulating the activity of BFCs by flowing a norepinephrine (NE ) solution (1 µM ).     

Cuprate-ferrate compositions for temperature independent resistive oxygen sensors

In this contribution, the binary ceramic system La₂CuO₄-LaFeO₃ is investigated for resistive oxygen sensor applications. The temperature-independent characteristics that are observed for copper contents of 30% or higher are of particular interest. In order to correlate sensor characteristics and material composition, an initial model describing the complex two-phase system is proposed. It is based on the so-called generalized effective media theory (GEMT), a useful tool for describing bi-phase composites. The fitting procedure allows to predict the actual sensor characteristics determined by the experiments.