Performance evaluation of grid connected wind energy conversion systems with five-phase modular permanent magnet synchronous generators having different slot and pole number combinations

The performance of modular permanent magnet machines depends on proper selection of the pole and slot numbers which results in negligible coupling between phases. Preferred slot and pole number combinations eliminate the effect of low order harmonics in the stator MMF, thereby reducing vibration and stray loss. In this paper, three machines, with identical dimensions, are designed with different slots per phase per pole (SPP) ratios. The mathematical model of the machine based on modified winding function is presented. FEA is used to determine the flux linkage vector due to the permanent magnet. A simulation study is carried out to compare the performance of the three machine designs when used in wind energy conversion systems grid connected with hill climbing maximum power point tracking. The comparison is based on machine torque density, resulting ripple torque, and machine efficiency.