Design of A Three-axis Helmholtz Coil for Magnetic Sensor Calibration

Abstract

Accurate measurement of magnetic sensor components is always an important issue in magnetic field applications, but there are unavoidable errors in the sensor system that need to be corrected before use. The common scalar correction method is difficult to effectively correct the sensor component because it requires a uniform and stable background magnetic field and depends on the magnetic field modulus. Therefore, a set of triaxial Helmholtz coils that can be used for sensor vector correction is designed to generate a controlled standard magnetic field. The design index of the coils, the size of the uniform zone, and the relationship between the magnetic field and the current were analyzed to provide a basis for the effective calibration of the sensor components. The measurement results show that the size of the uniform zone and the accuracy of the magnetic field of the coils designed in this paper meet the design requirements. Meanwhile, by using the coils in the calibration of the sensor array and the positioning of the magnetic target, the sensor error is reduced by three orders of magnitude, and the positioning accuracy of the magnetic target reaches 0.1 m with good practical effect.