A Giant Magneto Resistive (GMR) Effect Based Current Sensor With a Toroidal Magnetic Core as Flux Concentrator and Closed-Loop Configuration

• Published in: IEEE transactions on applied superconductivity Vol. 24; no. 3; pp. 1 - 5
• Main Authors: Yang, Xiaoguang, Liu, Hang, Wang, Yuanyuan, Wang, Youhua, Dong, Guoya, Zhao, Zhenghan
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Chips; Closed-loop; Current measurement; current sensor; Electronics; Error detection; Exact sciences and technology; Feedback; Finite element analysis; General equipment and techniques; Giant magnetoresistance (GMR); Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Integrated circuits; Magnetic cores; Magnetic hysteresis; Magnetoelectric, magnetostrictive, magnetoacoustic, magnetooptic and magnetothermal devices. Spintronics; Mathematical models; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensitivity; Sensors; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Superconductivity; toroidal magnetic core; Toroidal magnetic fields; Winding; Windings; Magnetoresistive device; Closed loop; Magnetic flux; Measurement sensor; Feedback regulation; Magnetic hysteresis; Giant magnetoresistance; Chip; Sensitivity; Current sensor; Feedback; Closed-loop; Toroidal shape; Magnetic core; System simulation; toroidal magnetic core; Mathematical model; Giant magnetoresistance (GMR); Machine windings
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2013.2286396

This paper presents a novel current sensor, which includes a giant magnetoresistance (GMR) chip, a toroidal magnetic core, and a feedback winding on the core. The mathematical model of the sensor was built, which was used to analyze the influence factors of the closed-loop current sensor. The closed-loop configuration with the magnetic core and the feedback winding improved the sensitivity of the sensor, eliminated the offset and drift related to temperature of the chip, and greatly reduced the error caused by magnetic hysteresis phenomenon. The simulation and test results showed that the novel current sensor has very low linear error (less than ± 0.7%). The designed sensor can measure frequency of currents up to 100 kHz. The current sensor has high linearity with the range from 10 mA to 20 A.