Shaded pole motor design and evaluation using coupled field and circuit equations

The circuit and field equations of the shaded pole motor are combined to provide a system of differential equations that completely describe it. The Crank - Nicolson - Galerkin method is used for the finite element formulation of the parabolic field equations and the solution in the time domain. A true time solution is described, where the rotor movement is modelled, along with the time variation of the iron permeability. The field is completely determined at every point in the motor cross section. Both current densities in the conductors and flux densities are calculated from this solution, allowing the estimation of torque, currents and losses.