Polyphase induction motor performance computed directly by finite elements

Finite element analysis is used to directly compute torques and currents of an induction motor, without need for any equivalent circuit. The AC voltages are applied by means of 0D and 1D finite elements, and the fields and related parameters are computed by nonlinear transient finite element analysis with adaptive time stepping. Equations are derived that allow balanced polyphase motors to be analyzed at any speed without rotating the rotor finite elements, and for torque to be computed directly from power loss. Computed torques and currents of a typical highly saturated polyphase motor with closed rotor bars are shown to agree quite well with measurements.