A 2MW 6-phase BLDC generator developed from a PM synchronous generator for wind energy application

In the direct drive wind turbine application, a PMSM generator often works together with a diode rectifier, which connects to a boost converter. In this paper, a six-phase BLDC generator is developed from the prototype design of three-phase permanent magnet synchronous generator. The diode rectifier is adopted. The cases the with different loads are studied. The finite element simulation shows the developed BLDC generator is better than the PMSM generator in terms of DC voltage ripple and torque ripple. Furthermore, the volume of the BLDC generator is smaller, despite of more permanent magnet is required. The efficiencies and the costs are also compared. As the result shows, BLDC generators connected with the diode rectifiers are good candidates for direct drive wind turbines.