Robust electromagnetic design of Transverse Flux Machines for high volume production

Transverse Flux Machines are attractive for a number of applications where a high torque is required at a relatively low rotational speed. A typical drawback of motors of this type is a high cogging torque in relation to the overall torque output of the motor, this leads to a high torque ripple which can cause unwanted noise and vibration. A number of techniques have been developed that reduce this cogging torque, however for high volume production these techniques need to have a low sensitivity to tolerances and variations in production. This paper focuses on how even small misalignments between phases can influence the cogging torque produced by a motor and how taking this into account in the design procedure can create a robust motor design with low cogging for a wide range of alignments.