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A passive current sensor employing self-biased magnetoelectric transducer and high-permeability nanocrystalline flux concentrator

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Rare Metals 2022年第7期41卷 2343-2348页

作者： Ji-Tao Zhang Yu-Mei Wen Ping Li Research Center of sensors and Instruments College of Optoelectronic EngineeringChongqing UniversityChongqing 400044China Department of Smart Grids and Information Engineering College of Electric and Information EngineeringZhengzhou University of Light IndustryZhengzhou 450002China

A passive current sensor,consisting of SmFe_(2)/PZT/SmFe_(2)self-biased magnetoelectric(ME)composite and Fe_(73.5)Cu_(1)Nb_(3)Si_(13.5)B_(9)nanocrystalline flux concentrator for weak current detection at power-line frequency,was fabricated and *** magnetostrictive material of SmFe_(2)plate with large anisotropic constant provides a huge internal anisotropic field to bias the ME transducer in closed magnetic ***,the additional magnetomotive force induced by the internal field and the corresponding increased effective permeabil-ity contribute to the improvement of the *** results demonstrate that the presented sensor has a higher sensitivity of 152 mV·A^(-1)at 50 Hz with a slight nonlinearity of~0.01%full scale(FS)and matches well with the predicted *** presented current-sensing device exhibits approximately 2.3 times higher sensitivity than that of conventional ME composite with[Pb(Zr_(0.48),Ti_(0.52)O_(3)](PZT)and Terfenol-D plates serving as a key sensitive *** addition,time stabilities of the presented sensor were evaluated for a long period of 72 h and analyzed through mathematical statistics method,and favorable stabilities with an uncertainty of 0.5μV are obtained in continuous 1 h *** results provide a significant advancement toward promising application of the tri-layer self-biased ME laminate for power-line elec-tric cords monitoring.

关键词： Magnetoelectric effects current sensor Magnetic flux concentrator Magnetostrictive rare earth iron alloys

Adaptive switching frequency buck DC-DC converter with high-accuracy on-chip current sensor

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Journal of Semiconductors 2015年第5期36卷 111-119页

作者：江金光黄飞熊智慧 Global Navigation Satellite System Research Center Wuhan University

A current-mode PWM buck DC-DC converter is proposed. With the high-accuracy on-chip current sen- sor, the switching frequency can be selected automatically according to load requirements. This method improves efficiency and obtains an excellent transient response. The high accuracy of the current sensor is achieved by a simple switch technique without an amplifier. This has the direct benefit of reducing power dissipation and die size. Additionally, a novel soft-start circuit is presented to avoid the inrush current at the starting up state. Finally, this DC-DC converter is fabricated with the 0.5μm standard CMOS process. The chip occupies 3.38 mm2. The accuracy of the proposed current sensor can achieve 99.5% @ 200 mA. Experimental results show that the peak efficiency is 91.8%. The input voltage ranges from 5 to 18 V, while a 2 A load current can be obtained.

关键词： DC-DC switching frequency current sensor soft-start wide load range

Design, optimization, and measurement of closed-loop Hall effect current sensor

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Science China(Technological Sciences) 2014年第9期57卷 1877-1882页

作者： CHENG XingGuo LI FuAn ZHANG ZongYang LIU Sheng Institute for Microsystems State Key Laboratory for Digital Manufacturing Equipment & Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology College of Physics & Electronics Engineering Hubei University of Arts and Science School of Energy and Power Engineering Huazhong University of Science and Technology School of Power and Mechanical Engineering Wuhan University

A kind of closed-loop Hall effect sensor is designed and fabricated by considering several factors such as iron core material, Hall device, as well as selected integrated circuit. Through studying the effect of the iron material and structures of current sensor, a kind of optimal Hall effect current sensor is found. The experimental results show that the presented closed-loop Hall effect current sensor achieves 1 mA/A sensitivity. And its lineafity and accuracy are 0.1% and 0.35% FS, respectively, at cur- rents ranging from 0 to 50 A.

关键词： current sensor optimized magnetic core structure magnetic properties

A new current sensor incipient fault diagnosis method for converters in wind energy conversion systems

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Science China(Information Sciences) 2022年第5期65卷 276-277页

作者： Songbing TAO Youqiang HU Shuiqing XU Yi CHAI Ke ZHANG College of Automation Chongqing University College of Electrical Engineering and Automation Hefei University of Technology

Dear editor,The efficient and clean characteristics of wind energy have led to the development of wind power generation as one of the most sophisticated ways of power generation [1]. To guarantee the reliability and safety of the energy conversion process, current sensors have played a significant role in the wind energy conversion systems (WECSs). However, to the best of the author’s knowledge, the literature concerning current sensor fault diagnosis is limited.

关键词： Incipient fault current sensor Fault diagnosis Wind power Instantaneous amplitude Fault location

Magneto－optic　current　sensor　Based　on　Total　Reflections　in　a　Quadrangular　Bulk　Glass

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Semiconductor Photonics and Technology 1996年第3期2卷 232-235页

作者： CHEN Xikun QIU Jinghe ZHU Qibiao DAI Laifa(Shanghai University. Shanghai 201800, CHN)

A novel optical device of a bulk glass Faraday current sensor is presented,which has a accuracy of 0. 5 in the current region of 1 000- 8 000 A and over a temperature range from-30℃ to + 40℃. The new sensing device can compensate the phase difference between p and s components of the incident light caused by total internal reflections in a glass. The self-correction, auto-correlation and auto-amplification techniques are used in the signal treatment with the help of a computer.

关键词： Total Reflection Faraday Effect current sensor

Design of Weak current sensor Based on Rogowski Coil

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Design of Weak Current Sensor Based on Rogowski Coil

THE DEVELOPMENT OF SAW current sensor BASED ON THE MAGNETOSTRICTIVE EFFECT

第43届中国控制会议

作者： Yifeng Gao Xiaojun Wang Lening Wang School of Automation Southeast University

In order to expand the application scenarios of the Rogowski coil and extend its limitations in weak signal measurements,a comprehensive design approach for the Rogowski coil is *** paper begins with an analysis of the basic structure and measurement principles of the Rogowski *** are made to understand how various parameters impact the performance of the Rogowski coil,and simulation validations are *** study investigates the specific influence of structural parameters on measurement performance and proposes a set of design procedures for Rogowski coils tailored to different performance metrics and signal ***,using a specific scenario as an example,a Rogowski coil measurement sensor is designed based on the conclusions drawn *** designed sensor features a nickel-zinc ferrite core with a 10MHz wide bandwidth,high sensitivity,high mutual inductance coefficient,and a compact size for weak signal *** results demonstrate the excellent performance of the designed Rogowski coil,meeting the measurement requirements for high-frequency weak signals.

关键词： Rogowski coil current sensor Weak signal detection

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THE DEVELOPMENT OF SAW CURRENT SENSOR BASED ON THE MAGNETOST...

current-voltage characteristics of lead zirconate titanate/nickel bilayered hollow cylindrical magnetoelectric composites

2015全国压电和声波理论及器件技术研讨会

作者： Ya-na JIA Wen WANG State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences

In order to achieve a kind of high-performance current sensor with high sensitivity and low temperature drift,this paper put forward a kind of new current sensor combined the surface acoustic wave(SAW)technology with magnetostrictive effect,analyzed its response mechanism and improve its temperature *** SAW current sensor used dual-delay-line oscillators based on 128°YX-LiNbO piezoelectric substrate as sensing *** piezoelectric substrate surface was covered with SiO thin layer whose temperature coefficient polarity is opposite to improve the temperature stability,and one of the SAW delay lines was sputtered with magnetostrictive FeCo film in response to *** magnetic field of the desired current induces the FeCo film’s magnetostrictivestrain and AE effect,changes the SAW propagation *** the Helmholtz coil,the developed SAW current sensor was characterized,high sensitivity,and good linearity were observed in the current experiment.

关键词： SAW current sensor Magnetostrictive effect FeCo film

来源： cnki会议评论

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Chinese Physics B 2010年第2期19卷 429-434页

作者：潘德安张深根田建军孙俊赛 Alex A.Volinsky 乔利杰 School of Materials Science and Engineering University of Science and Technology Beijing Faculty of Materials and Metallurgical Engineering Kunming University of Science and Technology Department of Mechanical Engineering University of South FloridaTampa FL 33620USA

current--voltage measurements obtained from lead zirconate titanate/nickel bilayered hollow cylindrical magnetoelectric composite showed that a sinusoidal current applied to the copper coil wrapped around the hollow cylinder circumference induces voltage across the lead zirconate titanate layer thickness. The current--voltage coefficient and the maximum induced voltage in lead zirconate titanate at 1~kHz and resonance （60.1~kHz） frequencies increased linearly with the number of the coil turns and the applied current. The resonance frequency corresponds to the electromechanical resonance frequency. The current--voltage coefficient can be significantly improved by optimizing the magnetoelectric structure geometry and/or increasing the number of coil turns. Hollow cylindrical lead zirconate titanate/nickel structures can be potentially used as current sensors.

关键词： current--voltage coefficient bilayered cylindrical composites electromechanical resonance current sensor

DSP ＆ FPGA-based control architecture for a highly integrated robot hand with enhanced impedance performance

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High Technology Letters 2010年第2期16卷 178-183页

作者：吴克 Lan Tian Chen Yangbin Liu Yiwei Jin Minghe Fan Shaowei Chen Zhaopeng Liu Hong State Key Labomtory of Robotics and System Harbin Institute of Technology Harbin 150001 P.R. China Ningbo GQY Video ＆ Telecom Stock Joint Co. Ltd Shanghai 201206 P.R. China Institute of Robotics and Mechatronics German Aerospace Center Wessling DLR 82234 Germany

A novel control system is developed to improve the capabilities of robet hand performing tasks in a variety of environments. A joint impedance control strategy has been successfully implemented in the low level control of a highly integrated robot hand. At flint, a real time controller with DSP＆FPGA-based multilevel control architecture is built. Then a current sensor of the single direct current （DC） link is used to measure and reconstruct the three phase currents, and a stable current signal is measured by optimizing sample instant. The experimental results of the joint impedance control show that the proposed method not only improves the effectiveness of contact environment performance, but also provides compliant interaction of robot hand with a person, which is very important for the development of friendly human robot of the next generation.

关键词： impedance control DSP & FPGA direct current (DC) link current sensor robot hand control system