Numerical modelling of eddy-current testing taking into account the effect of the measuring circuit

The volume integral method is combined with a circuit solver for the modelling of eddy-current inspection applications by taking into account the effect of the measuring circuit. It is demonstrated that the latter may result in noticeable deformations of the acquisition signals for specific inspection situations, thus it cannot be eliminated by simple calibration; this effect becomes increasingly important when the measuring frequency approaches the probe resonance. Comparisons of the simulation results with experimental data demonstrate the necessity of accounting for the circuit effect for inspection in driver pickup mode and verify the validity of the approach.