High torque density transverse flux permanent magnet machine design for wind power generation

The size of installed offshore wind turbines is continuously growing every year in an attempt to make this technology more cost-effective. Following this trend, the main challenge for wind turbine manufacturers is to reach the 10 MW power level. However, present topologies of electric generators may have prohibitive mass and volume when designed for such a high power application. In this paper an innovative transverse flux permanent magnet (TFPM) generator topology with a disk shaped rotor is presented with a very high torque density. The design has been performed by means of 3D-FEM software and optimized in order to increase the power factor and reduce the total volume for a 10 MW power goal. The efficiency is later improved by using a higher quality alloy for the construction of the iron cores. The proposed topology is able to reach a torque density of 57.42 kNm/m3.