풍력발전용 3MW급 매립형 영구자석 동기 발전기 설계

Abstract

In this report, a 3MW class interior permanent magnet synchronous generator (IPMSG) for wind turbine is designed. IPMSG has advantage in mechanical stability and resistance to demagnetization compared to the more conventional surface mounted permanent magnet synchronous generator (SMSG). The targeted IPMSG has a high rated rpm to minimize the active materials such as NdFeB permanent magnets, electrical steels, coppers. With same stator geometry, two types of rotor geometry is analyzed depending on the placement of the magnets. One type is mainly embedding the magnet along the surface of the rotor with radial magnetization (V-shape), the other type is embedding the magnet in radial direction with tangential magnetization (A-shape). To optimize IPMSG rotor geometry, various rotor parameters including position of the magnet, magnet thickness and other rotor geometries are changed to determine optimized rotor structure. And rotor structure is discrete skewed to reduce THD and cogging torque. The parameters of designed generators are compared after final optimization. It is found that for A-type rotor geometry is more optimal for magnet material and total weight. If we can increase the diameter slightly (by 10%) V-shape rotor geometry is preferable for less magnet use/total weight, and shorter axial length.