Ultra-fast finite element analysis of brushless PM machines based on space-time transformations

A computationally-efficient method is proposed for the steady-state performance simulation of brushless permanent magnet (BLPM) motors. Only a minimum number of magneto-static FEA solutions are used in conjunction with space-time transformations, which are based on the periodicity specific to synchronous machines. For an example interior permanent magnet (IPM) motor with six teeth per pole, a single magneto-static FE solution was employed to estimate the flux density time waveforms in the stator teeth and yoke. Other results include core losses, back EMF and torque. The extension of the method to fractional slot topologies with reduced number of teeth is discussed with reference to a 9-slot 6-pole IPM motor example. The results compare satisfactorily with those obtained from substantially more laborious time-stepping FEA.