Passive-rotor Disk-shaped Transverse Flux Permanent Magnet Machine with Reduced Cogging Torque

High torque density at low speed is one of the main characteristics of applications such as wind turbines and traction systems. Permanent magnet transverse flux machines exhibit this features owing to their high-energy magnetic flux, which is normal to current and motion vector. The machine's specific geometry magnifies cogging torque that further increases torque ripple, noise, and mechanical vibrations. This paper presents a cogging torque reduction method of the transverse flux permanent magnet generator using a novel passive-rotor disk-shaped topology for wind applications. The modified structure is discussed as well as the finite element analysis is performed to validate the proposed machine performance. Furthermore, the machine performance is compared to that of with the permanent magnet transverse flux machines without modifications.