Broadband Point Measurement of Transient Magnetic Field Based on Magneto-resistance Effect

Abstract

With the development of smart grid, the invasion of the transient magnetic field on secondary side low-voltage equipments and instruments in substations is increasingly prominent. Therefore, effective tools for transient electromagnetic field testing and assessment are imperatively needed. Existent transient magnetic field measurements in substations mainly rely on induction coil. The inductance, self-resistance, stray capacitance, radius, turns and materials of induction coil may directly affect the performance of the measurement, limiting its applications. This paper developed a novel transient magnetic field testing system, whose magnetic probe is developed based on magneto resistive effect. The probe uses three-axis magneto resistive sensor instead of induction coil, having the characteristics such as small size, high accuracy, and strong stability. It can achieve the point measurement of the magnetic field accurately, providing an effective mean for transient magnetic field testing.