Two New Rotor Designs with Reduced Amount of Rare-Earth Magnet Material for a Permanent Magnet Wind Generator for a 4MW Application

This paper presents two new rotors for permanent magnet wind generators, which should reduce the amount of the rare-earth materials of a wind generator. The design of one rotor is based on an existing new magnet arrangement and will be adapted for a new power of 4MW. The second rotor will be designed by adding v-shaped internal magnets to the first rotor. These two new rotors will be designed in an iterative process assuming the same geometry and electrical constrains and then compared to a conventional rotor by means of finite element analysis. The results show that the new rotor can save about 12% of magnetic material, while the new rotor with v-shaped magnets can even save about 14% of magnetic material.