A pot-core eddy current sensor based on DC magnetization

Abstract

Abstract Due to the limitation of the skin effect of traditional eddy current sensors, it is difficult to sense internal defects. This paper proposes a pot-core eddy current sensor based on DC magnetization, which uses DC magnetization to excite the permeability perturbation of internal defects in the surface of samples and uses a pot-core eddy current sensor with higher efficiency to sense the perturbation, thus realizing the detection of defects. The phenomenon of permeability perturbation is analyzed by simulation, and experiments are conducted to verify the performance of the sensor. Also, the effects of magnetizing current and defect size are investigated experimentally. The results show that the sensor can realize the detection of the small internal defect with an unsaturated magnetizing current.