Triaxial decoupling self-zero-setting fluxgate magnetometer zero point measurement circuit

Abstract

The invention discloses a triaxial decoupling self-zero-setting fluxgate magnetometer zero point measurement circuit, and the circuit employs a bipolar intermittent pulse excitation unit composed of low-power-consumption temperature control crystal oscillator to carry out the excitation of an iron core. The circuit employs the temperature control crystal oscillator to stabilize the work frequency, enables the iron core to be demagnetized in real time in a mode of bipolar excitation, and employs an intermittent pulse voltage excitation waveform to greatly reduce the power consumption. The circuit controls a constant voltage source to carry out the excitation of the iron core through a low-resistance switch, and greatly improves the energy utilization efficiency of the excitation unit. The circuit provided by the invention employs a weak coupling mode to install a triaxial magnetic probe, reduces the triaxial coupling error through the optimization of the relative position of the triaxial magnetic probe, employs a zero point automatic measurement circuit, can carry out the programming control to achieve the online detection of a circuit zero point, and can be used in the fields of magnetic field measurement and magnetic object detection.

Description

technical field [0001] The invention belongs to the technical field of magnetic field measurement or magnetometer, and more specifically relates to a zero-point measurement circuit of a three-axis decoupling self-adjusting fluxgate magnetometer. Background technique [0002] Fluxgate magnetometer is a precision magnetic field vector measuring instrument, which is widely used in satellites, geomagnetic scientific observation, resource exploration, weak magnetic field measurement, industrial control and military applications. The basic requirements for the fluxgate magnetometer are high precision, high resolution, good long-term zero stability, good linearity, and low attack consumption. However, the improvement of various technical indicators requires a high price, and some indicators restrict each other. For example, in order to maintain the stability of the long-term working zero point, double iron cores, ring or racetrack-shaped iron core structures are commonly used at pr...

AI Technical Summary

Problems solved by technology

In order to reduce the power consumption of the magnetometer to the milliwatt level, the excitation waveform with a narrow pulse width is often used; the working state of the magnetometer probe core is unstable and is greatly affected by time and temperature, making the output of the magnetometer The noise is large, and the temperature drift and time drift of the circuit zero point are serious. At present, the resolution of the milliwatt-level low-power fluxgate is 5-10nT, but the long-term zero point drift is above 100nT, which is difficult to apply to the field of precision measurement.

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