Acceleration of eddy current computation for scanning probes

In this paper, a novel method for accelerating eddy current computation based on the finite element method (FEM) is proposed for scanning probes or sensors over a plate sample. Due to the fact that eddy current and electromagnetic field distributions between adjacent probe positions are similar, a method is presented to accelerate the probe motion calculation. The solution of the field quantities under the position of each probe, which involves finding the solution to a system of linear equations using iterative methods such as conjugate gradients squared (CGS) and bi-conjugate gradients stabilised (BICGS), is accelerated using an optimised initial guess, the final solution from the previous adjacent probe position. This method is proven to quicken the convergence of the CGS/BICGS solving process, by reducing the number of iterations reaching the same relative residuals or reaching smaller residuals with the same number of iterations.