Giant magnetoresistance effect current sensor

Abstract

The invention relates to devices for measuring currents, in particular to a giant magnetoresistance effect current sensor with a magnetic shielding shell and a bias coil. The giant magnetoresistance effect current sensor comprises the U-shaped magnetic shielding shell, a giant magnetoresistance chip, a bias coil winding, a current-carrying conductor, a PCB, a bias current source and a signal processing circuit, wherein the probe of the giant magnetoresistance effect current sensor is formed by the U-shaped magnetic shielding shell, the giant magnetoresistance chip, the bias coil winding, the current-carrying conductor and the PCB, the signal processing circuit comprises a bias magnetic field generating circuit, a giant magnetoresistance chip supply voltage switching circuit, a reference voltage generating circuit and an improved difference operational amplification circuit, the magnetic shielding shell overcomes the defect that magnetic fields are prone to being simultaneously influenced by an outside stray magnetic field due to the high sensitivity of giant magnetoresistance on the magnetic fields, and meanwhile hysteresis errors are reduced and alternate and direct currents are precisely measured through the method of providing the bias coil winding for a bias magnetic field.

Description

technical field [0001] The technical solution of the invention relates to a device for measuring current, specifically a giant magnetoresistance effect current sensor. Background technique [0002] With the development of power electronics technology, the demand for high-performance compact current sensors is gradually increasing. Traditional current detection methods include shunts, current transformers, Rogowski coils, and Hall sensors; new current detection technologies include fluxgate sensors, giant magnetoresistance effect current sensors, and fiber optic sensors. In contrast, the giant magnetoresistance effect current sensor has its own outstanding advantages and unique magnetic induction ability. The giant magnetoresistance effect current sensor has the characteristics of high sensitivity to applied magnetic field, high operating bandwidth range, excellent temperature stability, low power consumption and miniaturization. [0003] However, due to the high sensitivit...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a giant magnetoresistance effect current sensor, which is a giant magnetoresistance effect current sensor with a magnetic shielding shell and a bias coil. The highly sensitive characteristics make them vulnerable to the defects of external stray magnetic fields; at the same time, the method of providing a bias magnetic field through the bias coil winding reduces the hysteresis error and realizes accurate measurement of AC and DC currents

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