Low Frequency Eddy Current Method for Internal Defect Inspection of Steel Structure

This paper proposes a low frequency eddy current method for inspection of internal defect in steel structures. A magnetic sensor system for exciting field is designed to enhance sensitivity and not to cause magnetic saturation. Inspection process is explained with a nonlinear equivalent electric circuit. The designed magnetic sensor system is analyzed by finite element method. The results of experiment are compared with the analysis results to validate the proposed method.