Simulation Analysis of Multi-Frequency Eddy Current Sensor Impedance Property

Multi-frequency eddy current test technique is applied in the industrial non-destructive testing more and more widely. Every frequency component contains the useful information and the harmful noise when the eddy current sensor is excited by several sine signals. The impedance property of the sensor is a key element in the test system, so this paper analyzed it by finite element method simulation. The simulation results show the variation law of the impedance in the air and on the nonferromagnetic metal plate in different frequencies, and the law is helpful for the signal processing of multi-frequency eddy current testing.