计及斜槽时非导磁螺钉对永磁同步发电机性能影响的分析

采用非导磁螺钉是一种常见的永磁发电机转子表面磁钢固定方式,非导磁螺钉的存在减小了磁钢有效面积进而会影响电机内部磁场分布.为了研究非导磁螺钉对永磁电机运行性能的影响,采用时步有限元法,在计及定子斜槽条件下,对非导磁螺钉安装和绑扎式安装的表面磁钢永磁同步发电机的气隙磁密、空载感应电动势以及齿槽转矩进行了详细分析.与绑扎式固定方式相比,非导磁螺钉所在截面的气隙磁密谐波含量较明显,7次谐波含量由11.7％增加至38.8％,但电机感应电势及齿槽转矩变化不大.

Analysis on the Influence of Non-magnetic Screws on PMSG Performance Taking Skewed Slot into Account

Using non-magnetic screw is a common method to fix the permanent magnet on the rotor.Non-magnetic screws will reduce the magnets effective area and then affect the internal magnetic field distribution characteristics of the motor.To analyze the influence of non-magnetic screws on PMSG’s performance,this paper analyzes the electromagnetic field calculation with Time-stepping finite element method of surface magnets PMSG in non-magnetic screws method and banding method considering of stator skewed slot at three aspects,these three aspects are airgap flux density,no-load EMF and cogging torque.Compared with banding method,the air-gap flux density harmonic content of non-magnetic screws method is more obvious,it is mainly because the seventh harmonic was raised from 11.7% to 38.8%.The induced potential and cogging torque changed a little.