Design analysis by finite-element time-stepping techniques

It has become necessary to develop analysis techniques to predict losses, torque variation and the interaction between motors and inverters. The authors describe the development of a nonlinear finite-element time-stepping method which allows for the distribution of stator currents in slots, external circuits and rotor movement. To check the accuracy of the method, comparisons between test and calculations are made for an Exe induction motor at standstill and a synchronous motor operating from a current-fed inverter