大功率永磁辅助同步磁阻牵引电机磁极优化

永磁牵引系统是下一代轨道交通的发展方向,但高速惰行、带速重投和匝间短路等难题阻碍了永磁牵引的应用,永磁辅助同步磁阻电机是解决上述难题的最佳选择。总结了永磁辅助同步磁阻电机的设计方法,设计了3层U型磁障大功率牵引驱动电机,给出了各层磁障对应的极弧系数和磁障张角以及永磁体最佳尺寸比。提出用偏心气隙结合不均匀磁桥对磁极结构进行优化。发现气隙比为1.63时,抑制转矩脉动的效果最佳;而不均匀磁桥不仅可以降低转矩脉动,还使转子的机械强度得到提高。对所设计的380 kW永磁辅助同步磁阻牵引电机的分析表明,所提出的方法可有效地降低转矩脉动。

Pole optimization of high power permanent magnet assisted synchronous reluctance traction motor

The permanent magnet traction system is the development direction of the next generation of rail transport.However,the problems of high-speed coasting,restarting at unknown speed,and turn-to-turn short-circuit fault prevent the application of permanent magnet traction.Permanent magnet assisted synchronous reluctance motor is the best choice to solve the above problems.The design method of the permanent magnet-assisted synchronous reluctance motor is summarized,and a high-power traction drive motor with three-layer U-shaped magnetic barrier is designed.The pole arc coefficient,the angle of magnetic barrier and the best size ratio of permanent magnet are given.A method of an eccentric air gap combined with an unequal-width magnetic bridge is proposed to optimize the magnetic pole structure.It is found that the effect of suppressing torque ripple is best when the air gap ratio is 1.63;the unequal-width magnetic bridge can not only reduce the torque ripple,but also improve the mechanical strength of the rotor.The analysis of the designed 380 kW traction motor shows that the method proposed in this paper can effectively reduce the torque ripple.