Single winding annular fluxgate current sensor

Abstract

The present invention provides a single winding annular fluxgate current sensor. The single winding annular fluxgate current sensor adopts a permalloy as magnetic core material of a fluxgate probe, a generated fluxgate signal has an enough high signal to noise ratio, a secondary winding is not need to generate a compensation magnetic field to form the enclosed loop feedback, and the error correction and the signal amplification can be carried out by entering a signal conditioning circuit directly, so that according to the present invention, a conventional dual-winding coil is changed into a single-winding coil, the conversion from a current signal to the fluxgate signal and to a voltage signal can be realized by just using one primary winding, and accordingly, the current signal in a measured current line can be measured, not only the product process is simplified, but also the product reliability is increased, and the precision is higher when the current signal of the measured current line is measured. According to the present invention, the signal conditioning circuit is also improved, and by conditioning an output signal via a two-stage amplifying circuit, the situation that the product performance does not degrade is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of current sensors, in particular to a single-winding annular fluxgate current sensor. Background technique [0002] The existing fluxgate current sensor technology is a dual-winding scheme, such as figure 1 As shown, the fluxgate signal is generated in the primary winding 11 through the excitation circuit 13, but the signal-to-noise ratio of the fluxgate signal is not high enough. If it is directly amplified, the current in the measured current line can be measured through the fluxgate signal The signal accuracy is not high, so the fluxgate signal needs to be filtered by the filter circuit 14 and conditioned by the signal conditioning circuit, and then the feedback compensation circuit 16 generates a compensation magnetic field on the secondary winding 12 to form a closed-loop feedback to improve the signal-to-noise ratio. In addition, the existing technology uses a silicon steel magnetic core, which makes...

AI Technical Summary

Problems solved by technology

[0002] The existing fluxgate current sensor technology is a dual-winding scheme, such as figure 1 As shown, the fluxgate signal is generated in the primary winding 11 through the excitation circuit 13, but the signal-to-noise ratio of the fluxgate signal is not high enough. If it is directly amplified, the current in the measured current line can be measured through the fluxgate signal The signal accuracy is not high, so the fluxgate signal needs to be conditioned by the signal conditioning circuit after being filtered by the filter circuit 14, and then the compensation magnetic field is generated on the secondary winding 12 by the feedback compensation circuit 16 to form a closed-loop feedback to improve the signal-to-noise ratio

In addition, the existing technology uses a silicon steel magnetic core, which makes the product larger and limits the versatility of the product; at the same time, the primary and secondary windings will increase the process complexity and reduce the product reliability.

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