Giant magnetoresistive effect current sensor using amorphous alloy magnetic ring structure

Abstract

The invention relates to a giant magnetoresistive effect current sensor using an amorphous alloy magnetic ring structure, and belongs to the technical field of power system measurement. In the current sensor, a wire to be measured passes through an amorphous alloy magnetic ring; and a direct current magnetic biasing coil is wound on the amorphous alloy magnetic ring and is powered by a direct current constant current source. A plurality of layers of giant magnetoresistive effect chips are arranged in an air gap of the amorphous alloy magnetic ring. Positive output ends and negative output ends of the chips are connected with the in-phase input end and the inverted input end of an instrument amplifier respectively; and an output end of the instrument amplifier is connected with an in-phase input end of an operational amplifier. A voltage following resistor is connected in parallel between an inverted input end and an output end of the operational amplifier; the output end of the operational amplifier is connected with an input end of an analog / digital converter; and an output end of the analog / digital converter is connected with a nixie tube display. The current sensor has the advantages of small size, low cost, low energy consumption, wide frequency response, high sensitivity, stabile characteristic and the like, and meets the requirements of environmental friendliness, energy conservation and large-scale distributed monitoring in a novel intelligent power grid.

Description

technical field [0001] The invention relates to a giant magnetoresistance effect current sensor adopting an amorphous alloy magnetic ring structure, which belongs to the technical field of power system measurement. Background technique [0002] At present, there are mainly three kinds of known current sensors used for power system measurement: traditional electromagnetic current transformers, fiber optic current sensors, and Hall effect current sensors. [0003] The traditional electromagnetic current transformer is based on the coil principle, and the current is measured through the induction of the coil. This type of electromagnetic current transformer is bulky, expensive, and difficult to install. The primary side and secondary side of the measurement cannot be electrically isolated, and the insulation requirements are high. They can only measure AC current and cannot be used for large-scale distributed monitoring. . The cost of fiber optic current sensor is too high, a...

AI Technical Summary

Problems solved by technology

This type of electromagnetic current transformer is bulky, expensive, and difficult to install. The primary side and secondary side of the measurement cannot be electrically isolated, and the insulation requirements are high. They can only measure AC current and cannot be used for large-scale distributed monitoring.

The cost of fiber optic current sensor is too high, and it is greatly affected by environmental factors, so it is still difficult for large-scale commercial application at present

Although the Hall-type current sensor has been widely used in the distribution network, the sensitivity of the Hall effect element is very low, and the measurement energy consumption is high, so it cannot be used in high-precision current measurement.

Images