Global accuracy of the FEM solutions based on Ampere's law for a highly saturated magnetic device with a large air-gap

The finite element method is widely used to model electromagnetic devices. Ensuring that the FE model is accurate is particularly important where measured data of the large prototypes are not available. This paper proposes to use Ampere's circuital law to obtain a global accuracy criterion that measures the accuracy of the whole FEM model and solutions. The accuracy of the FEM approximate solutions for highly saturated, nonlinear, magnetostatic field problems will provide a central focus for this paper.