A Vectorial Current Density Imaging Method Based on Magnetic Gradient Tensor
Author:
Wu Yangjing1ORCID,
Zhang Mingji1,
Peng Chengyuan1,
Zhang Zehuang1ORCID,
He Yichen1,
Zhang Wenwei1,
Chang Liang2
Affiliation:
1. Sino-German College of Intelligent Manufacturing, Shenzhen Technology University, Shenzhen 518118, China
2. State Grid Liaoning Electric Power Co., Ltd., Huludao 125000, China
Abstract
Magnetic current imaging is deemed an emerging powerful technique for visualizing electrical currents in electronic devices. However, the existing magnetic-field-based Fourier Transform back-evolution method is limited by its mono-function of imaging the magnitude of current density in devices under test, and subject to background noise distortion. Here, we developed a novel vectorial current density imaging method based on the detection of the magnetic field gradient generated by current carrying conductors. A closed form solution of current density inversion was analytically derived and numerically verified. Experiments were conducted by scanning tri-axial fluxgate sensor over different shapes of electrical wires. The results show that a current density resolution of 24.15 mA/mm2, probe-to-sample separation of 2 mm, and spatial resolution of 0.69 mm were achieved over a maximum scanning area of 300 mm × 300 mm. Such a method is verified to be capable of simultaneously imaging both magnitude and directions of current density, which is a promising technique for in situ noninvasive inspection for the power electronic and semiconductor industry.
Funder
National Natural Science Foundation of China
Guangdong Regular Universities Special Fund for Major Areas
Natural Science Foundation of Guangdong Province Science and Technology Program of Shenzhen
Special Project of Self-Made Experimental Instruments and Equipment in SZTU
Postgraduate Innovation Development Fund Project of Shenzhen University
Natural Science Foundation of Top Talent of SZTU
Subject
Electrical and Electronic Engineering,Biochemistry,Instrumentation,Atomic and Molecular Physics, and Optics,Analytical Chemistry
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