共查询到20条相似文献,搜索用时 5 毫秒
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超微晶合金在测量用电流互感器铁心中的应用 总被引:7,自引:0,他引:7
对测量用电互感器铁心的选材进行了比较分析,介绍了超微晶合金,冷轧硅钢片及坡莫合金软磁材料的特性,并给出了超微晶合金电流互感器铁心设计的实例。 相似文献
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介绍了超微晶合金材料的特性,分析了该新材料用于制造高压电流互感器的可行性,分析卫设计、制造过程中的关键技术问题及解决措施,并对采用该新材料与普通硅钢片和坡莫合金的互感器的经济技术指标进行了比较。 相似文献
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在线监测中用于绝缘介电特性测量的电流传感器 总被引:5,自引:1,他引:5
研究了高压输变电设备绝缘在线监测中用于介电特性测量的关键器件-电流传感器,介绍了电流传感器的工作原理、设计原则及对铁芯材料性能的要求,对传感器的误差进行了分析,研制出了精度高,性能稳定,结构简单,满足在线监测要求的电流传感器。 相似文献
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为降低绝缘子发生污闪的概率,需对影响绝缘子泄漏电流的温湿度值进行在线监测。为克服现有的在线监测温湿度技术在高环境温度和强电磁干扰等各种恶劣的环境下可靠性低的不足,采用了一种新的基于声表面波射频识别(SAWRFID)的绝缘子温湿度在线监测方法。首先对该SAW-RFID温湿度传感器标签芯片进行了通信测试、中心频率测试和性能测试,并基于该温湿度传感器对XP-70型绝缘子进行了实验,利用SAW-RFID温湿度传感器标签监测绝缘子温湿度,在此基础上分析得到了环境温湿度与绝缘子泄漏电流幅值的关系,为预估绝缘子绝缘性能提供了参考依据。 相似文献
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研制了一种用浓硫酸和浓硝酸修饰,以印制电路板为基底,用于检测SF6局部放电分解组分的碳纳米管传感器。分析了碳纳米管膜的导电模型,并通过真空下传感器的温度特性试验,对修饰前后的碳纳米管传感器的电阻随温度变化的关系进行了分析。在实验室采用SF6放电分解试验装置,用碳纳米管传感器对分解组分进行检测,结果表明用经混酸修饰后的样品制作出的传感器对SF6放电分解组分表现出较好的吸附性。此外,研究了温度对传感器吸附性能的影响,结果表明,温度在85℃时传感器表现出最强的吸附性。 相似文献
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Syed Usman Amin Muhammad Aaquib Shahbaz Syed Arsalan Jawed Muhammad Naveed Ayesha Hassan Asma Mahar Fahd Khan Noman Masood Danish Kaleem Zain Hussain Warsi Muhammad Junaid 《International Journal of Circuit Theory and Applications》2020,48(4):485-501
A wirelessly powered temperature sensor is presented in complementary metal-oxide-semiconductor (CMOS) 180-nm process. The wireless power transfer (WPT) is performed using resonant magnetic coupling, and a diode-less AC to DC conversion is achieved through a quadrature-oscillator with native-MOS. The quadrature-signals are subsequently used to control the diode-less rectifier switches. The on-chip temperature sensor exploits the subthreshold region temperature, and the sensed temperature is converted to frequency using a ring-oscillator, which is implemented using differential cross coupled oscillator-based delay cells. The temperature sensor architecture also employs a temperature-insensitive replica circuit to minimize process dependence and enhance power-supply rejection ratio (PSRR) of the sensing process. The application-specific integrated circuit has been designed and fabricated in 180-nm CMOS process and has dimensions of 2 mm × 2 mm. The measurement results demonstrate that the WPT circuit generates a DC voltage of 1V with a power transfer efficiency of 85% for distances 2 to 8 mm with settling time of microseconds to milliseconds. The temperature sensor demonstrates a resolution of < ±0.6C with a sensitivity of 0.52 mV/C and 126.9 Hz/C along with PSRR of −63dB and Integral Non-Linraity (INL) of 5% measured across six different dies. The back-scattering communication demonstrates a −53-dB signal at a distance of 4 mm without affecting the WPT efficiency. The total power consumption of the temperature sensor along with the integrated biases is 120 nW. 相似文献
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为了准确测量电力系统中设备关键节点的温度变化,综合考虑绝缘和电磁兼容要求,提出一种基于脉冲转换温度传感芯片的电力设备温度监测系统。该系统采用射频识别技术进行通信,同时采用蒙特卡洛分析法确定了传感器芯片误差修正方法,并提出误差修正公式。最后,在开关柜上进行实际测试。结果显示,本系统可真实反映温度变化,提升了温度测量精度,为准确实现电力设备温度监测提供了一种有效方法。 相似文献
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In automotive and industrial fields, pressure sensors are a key component for precisely controlling the mechanical systems. Conventional micro electro mechanical system (MEMS)‐based pressure sensors have an advantage in noise resistance, because both strain gauges and control circuits are integrated in one chip. However, the MEMS‐based pressure sensors are generally fabricated on an Si substrate, and have a low stability against various active gases. Thus, we have newly proposed a pressure sensor which consists of an Si‐based strain sensor set on a stainless steel diaphragm with a high stability against the active gases. The key technology is that a Koval plate is inserted between the strain sensor and the stainless steel diaphragm, for preventing the breakage or the delamination of the strain sensor at the bonding interface due to a difference in thermal expansion. Structure of the sensor including the shape and the size of Koval plate and the assembly position of the strain sensor were designed using structural simulation and experiments. Eventually, the 2.8 mm wide and 0.17 mm thick Koval beam was bridged on the stainless steel diaphragm for efficiently transmitting the diaphragm deformation to the strain sensor. The strain sensor was assembled at the edge of Koval beam with a glass bonding technique. Consequently, the developed pressure sensor has achieved a small dispersion of less than 1% F. S. in a temperature range from 0 °C to 85 °C. 相似文献
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为减小环境温度变化对压阻式压力传感器实施可靠测量的不利影响,提出一种结合三次样条插值与埃尔米特插值的补
偿方法。 首先通过标定实验获取标定数据,采用三次样条插值建立环境温度、传感器输出电压与待测压力之间的函数关系以补
偿传感器的温度误差,再借助埃尔米特插值构造输出电压与待测压力之间的映射关系描述传感器的测量特性。 两种标定工况
条件下压力传感器的温度补偿实验结果表明,经该方法补偿后的传感器测量最大引用误差分别为 2. 414×10
-4 和 6. 129×10
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平均引用误差分别为 2. 353×10
-5 和 1. 313×10
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、误差方差分别为 1. 751×10
-9 和 1. 613×10
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,零点温度系数分别为 2. 780×10
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和 8. 862×10
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,灵敏度温度系数分别为 1. 952×10
-6 和 3. 672×10
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,验证了该方法在不同建模数据条件下补偿性能的一致有
效性。 相似文献
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本文针对应变片式扭矩传感器的温度漂移现象,建立基于分段线性插值法的温度补偿模型,将扭矩和温度的二维标定数据嵌入到数据融合软件算法中,根据精度要求分为多个不同区间并将区间内的标定点代入线性表达式,输出预测扭矩值,从而实时矫正该传感器扭矩随温度的漂移,使其具有温度自补偿功能。研究结果表明,利用分段线性插值法补偿后该传感器的灵敏度温度系数由7.615×10^(-4)/℃提升至1.429×10^(-4)/℃,温度附加误差相对值由2.67%提升至0.5%,均提升了5倍以上。该方法简单有效,实现了扭矩传感器的实时温度补偿,提高了扭矩传感器的温度稳定性。 相似文献
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针对超高压系统3/2断路器接线方式的结构特点及存在问题,提出基于串断路器保护的继电保护改进新方案。该方案利用断路器两侧电流信息构成小差保护,单串内所有断路器小差保护组成串断路器保护。利用单串的串断路器保护与所对应线路保护相配合,站内所有串断路器保护与母线保护相配合,实现了对串内故障的准确定位,可有效缩小原有保护配置下部分区域切除故障时的停电范围,增强了继电保护的选择性,且该方案改造实施简便,具有较强的工程实用性。 相似文献
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针对非色散红外SF_6气体传感器测量精度易受环境温度、气压影响的问题,提出采用混合粒子群优化-误差反向传播(PSO-BP)神经网络预测模型对环境温度、气压变化引起的测量偏差进行实时补偿,并与其他补偿方法进行分析比较。实验结果表明,该SF_6气体传感器在气体浓度0~1000×10~(-6)、温度10~40℃、气压100~120 kPa,相对测量误差为1.5%,检测精度小于±15×10~(-6),检测分辨率为1×10~(-6),有效地消除了环境温度、气压波动引起的非线性影响。相比于经验公式法和RBF神经网络补偿方法,该方法具有较高的测量准确度和稳定性,且无需增加电路模块,有利于降低传感器的体积和成本。 相似文献
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Brad E Dicianno Donald M Spaeth Rory A Cooper Shirley G Fitzgerald Michael L Boninger Karl W Brown 《IEEE transactions on neural systems and rehabilitation engineering》2007,15(1):144-150
Innovations to control interfaces for electric powered wheelchairs (EPWs) could benefit 220000 current users and over 125000 individuals who desire mobility but cannot use a conventional motion sensing joystick (MSJ). We developed a digital isometric joystick (IJ) with sophisticated signal processing and two control functions. In a prior study, subjects' driving accuracy with our IJ was comparable to using an MSJ. However, we observed subjects using excessive force on the IJ possibly because its rigid post provides no positional feedback. Thus, this paper examines the time-series data recorded in the previous study to characterize subjects' force control strategies since weakness is a concern. Eleven EPW users with upper limb impairments drove an EPW using an IJ with two different control functions and an MSJ in a Fitts' law paradigm. Subjects relied upon positional feedback from the MSJ and used appropriate force. In contrast, subjects using the IJ with either control function applied significantly higher force than necessary (p < 0.0001 and p = 0.0058). Using higher average force was correlated with quicker trial times but not associated with accuracy. Lack of positional feedback may result in use of excess isometric force. Modifying control functions, adjusting gain, or providing additional training or feedback might address this problem. 相似文献