A comparison of methods for the solution of two-dimensional narrow gap problems

The choice of suitable methods for the solution of magnetostatic field problems with narrow gaps is discussed. A study featuring various possible methods is presented. In suitable test cases analytic conformal transformation results are compared to those obtained from boundary integral techniques and a differential formulation finite element approach. Guide lines are produced for cases where an analytic solution is not available. Results obtained from full non-linear solutions of a linear stepping motor are compared with a simplified analytic technique and experimental measurement.