Abstract

Small non-ferromagnetic metal particle and ferromagnetic metal particle could be detected with micro inductive sensor. However, the signal of the inductive sensor is very weak. In order to increase the amplitude of the signal, the relation between the material of magnetic core and the sensitivity of the micro planar inductive sensor is presented in this paper. Simulation models of the micro inductive sensor with different magnetic cores are built with Ansoft software. The simulation results indicate that the magnetic core with high permeability and high conductivity could improve the sensitivity of planar inductive sensor for the detection of both iron particles and copper particles. The simulation results also indicate that the sensitivity of detecting copper particles is increased with the increase in thickness of the iron magnetic core, but the sensitivity of detecting iron particles is decreased with the increase in thickness of iron magnetic core. This paper also introduced the recent patents which are designed to improve the sensitivity of inductive sensor. This research has reference value for the design of inductive sensor.

Keywords: Eddy current, inductive sensor, magnetic core, metal particle detection, micro sensor, oil monitoring.