Giant magnetoresistance current sensor

Abstract

The invention relates to a giant magnetoresistance current sensor and relates to a device for measuring currents. The giant magnetoresistance current sensor is composed of an electromagnetic conversion module, a signal amplification module and a feedback compensation module, wherein the electromagnetic conversion module comprises a magnetic core of a magnetism accumulation ring, a primary winding and a giant magnetoresistance chip, the signal amplification module comprises an operational amplifier and a push-pull power amplifier, and the feedback compensation module is a feedback winding. The whole measurement circuit forms a closed loop system, and the giant magnetoresistance chip and the magnetic core of the magnetism accumulation ring form a closed structure. The giant magnetoresistance current sensor overcomes the defects that a giant magnetoresistance current sensor in the prior art is very prone to interference of an external stray magnetic field, temperature drift and zero drift cannot be eliminated completely, and the measurement accuracy is affected by intrinsic magnetic hysteresis existing in a magnetic device.

Description

technical field [0001] The technical solution of the invention relates to a device for measuring current, specifically a giant magnetoresistance current sensor. Background technique [0002] With the development of power electronics technology, the application of high-precision, wide-band current sensors is becoming more and more extensive. Current sensors have made great progress in the past ten years. According to different measurement principles, current sensors are roughly divided into several types based on Ohm's law, electromagnetic induction law, Hall effect, Rogowski coil and fluxgate; according to different methods used, current sensors can be divided into contact type and non-contact type two types. Since the current measurement by the non-contact current sensor can ensure the personal safety of the staff and the stable operation of the system, the application range is wider. Non-contact current sensors are generally based on the measurement of magnetic fields. ...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is: to provide a giant magnetoresistance current sensor, the entire measurement circuit constitutes a closed-loop system, and the giant magnetoresistance chip and the magnetic core of the magnetic ring form a closed structure, which overcomes the giant magnetoresistance current sensor of the prior art. The sensor is easily disturbed by stray external magnetic fields during measurement, temperature drift and zero drift cannot be completely eliminated, and magnetic devices have inherent hysteresis phenomena that affect measurement accuracy.

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