3-D finite element analysis of the cogging torque of a transverse flux machine

The inverter-fed synchronous transverse flux machine with a permanent magnet excited rotor is well suited for the application with advanced drive systems for electric-driven city buses. The topology of such a machine requires three-dimensional finite element analyses to accurately predict the machine parameters. With regard to the mentioned application, the paper presents the evaluation of the electromagnetic cogging torque and the stray field in the rotor carrier. Both the shear stresses and the distribution of the magnetic flux density influence the choice about possible materials of the rotor carrier.