Fluxgate current sensor sampling resistor ripple current compensation method

Abstract

The invention discloses a fluxgate current sensor sampling resistor ripple current compensation method, which is characterized by comprising the following steps of in a current acquisition period, acquiring a ripple noise signal introduced by an excitation signal given by a square wave module generated by self-oscillation in a fluxgate current sensor circuit, carrying out amplification processing on the ripple noise signal by utilizing an analog amplification circuit, obtaining amplified ripple noise signals of a plurality of acquisition periods, performing digital processing on the collected amplified ripple noise signals of the plurality of acquisition periods, and converting the amplified ripple noise signals into noise offset signals, and inputting the noise offset signal into the fluxgate current sensor circuit through a digital-to-analog conversion module, and using the noise offset signal to offset the ripple noise of the fluxgate current sensor circuit. According to a result obtained by testing an existing model machine, the ripple noise in the current sensor can be remarkably reduced through the ripple noise counteracting function, and good stability is shown.

Description

technical field [0001] The invention relates to an open-loop electrical compensation and suppression method for modulation ripple of a fluxgate high-current sensor. Background technique [0002] Current sensors fall into two main categories: those based on Ohm's law of resistance and those based on Faraday's law of electromagnetic induction. Resistive shunts are a current sensor based on Ohm's law, and are widely used to measure instantaneous current pulses due to their fast rising speed and large amplitude. Due to the large measurement noise of conventional resistance shunts, the measurement results have large errors and are unstable. For measuring the large pulse current of 100kA, the skin effect will become the main limiting factor of the measurement bandwidth. For highly integrated electronics, coaxial resistive shunts are bulky, expensive, and generally only suitable for measuring fast current pulses. In most environments, surface mount devices (SMDs) using thick fil...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is: the excitation square wave of the current fluxgate current sensor utilizing nonlinear magnetic material characteristics will introduce the excitation signal frequency and the ripple noise of the frequency multiplication of the excitation signal frequency in the actual measurement results, which will affect the current high-precision measurement of

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