Effect of magnet coverage on torque, loss and torque ripple in a PMSM
Paper i proceeding, 2014

This paper address the effect of magnet coverage on the torque, iron and magnet loss components and torque ripple of two surface permanent magnet synchronous generators of 5MW. The values of torque, torque ripple, iron and magnet losses are calculated using a FEM program. It is concluded that the optimal magnet coverage can only be found by extensive investigations for each specific machine. However, an estimate value of magnet coverage can be found from recommendations and formulas, including only the number of phases and the number of slots per pole per phase. It is shown that by investigating each individual machine for a magnet coverage between 0.7-0.9, the torque ripple can be reduced up to 40% and magnet loss can be reduced up to 28%.

Permanent magnet machines

Surface permannt magnet synchronous generator (SPMSG)

Fractional slot winding

Integer slot winding


Poopak Roshanfekr

Chalmers, Energi och miljö, Elkraftteknik

Sonja Lundmark

Chalmers, Energi och miljö, Elkraftteknik

Torbjörn Thiringer

Chalmers, Energi och miljö, Elkraftteknik

Mikael C D Alatalo

Chalmers, Energi och miljö, Elkraftteknik

Proceedings, IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society





Elektroteknik och elektronik