Computer aided design of a shaded-pole electromagnet by the finite element method

The design of shaded pole electromagnets is performed using a suitable finite element procedure which computes nonlinear magnetic fields from the knowledge of the a.c. supply voltages. The proposed method gives the currents and the electromotive forces in the windings, the mechanical force on the movable core and the magnetic field distributions. The effects of the pole geometry and of the shading rlngs conductance are analyzed, in order to improve electromagnet performances. The experimental verifications validate the numerical results.