Saturable overlapping rectangular poles: Towards a functional relationship between force, overlap distance, mmf and saturation polarization

The transverse force and flux distributions are examined for the important case of overlapping rectangular poles of saturable material. Results from measurements on physical devices and from numerical iterative solutions of the field equations are presented, with flux plots for varying pole positions. Accuracy, as determined from control cases and other means, is better than 1%. The transverse force is presented in a novel way as a unique function of the three variables, the mmf, the overlap distance, and the saturation polarization of the pole material. This shows that the force is remarkably independent of overlap, and for large overlap is double the force for the corresponding linear case and directly proportional to both the mmf and the saturation polarization.