磁性槽楔对永磁电机转子损耗及温度场影响

Influence of magnetic slot wedge on rotor losses and temperature field of PMSM

针对实心转子高压永磁电机定子铁心开槽会导致气隙磁导不均匀,气隙中谐波磁场引起电机转子温度升高,影响永磁体的电磁性能的问题,以一台315 k W,6 k V实心转子高压永磁电机为例,建立了样机的二维电磁场时步有限元模型及三维全域流体与固体耦合传热数学模型,给出了求解域及边界条件,通过求解计算模型,将计算数据与实验数据进行了对比,验证了所建模型的正确性。在此基础上研究了槽楔相对磁导率分别为3、5、7、9时对转子表面涡流损耗的影响,分析了磁性槽楔相对磁导率为不同值时电机转子及定子各部分的温度分布,计算结果表明定子槽楔相对磁导率数值的增加,电机的起动转矩降低,转子铁心涡流损耗逐渐减小,电机定子各部分温度先减小后趋于稳定。

Stator core slots cause the air gap magnetic conductance of the solid-rotor high-voltage PMSM uneven. The harmonic magnetic field makes the temperature of the rotor rise and the electromagnetic properties of the permanent magnets are influenced. A 315 kW,6 k V high voltage solid rotor permanent magnet motor was taken as an example. The 2D electromagnetic step finite element model of the prototype and 3D fluid and solid coupling mathematical model of the entire solid-rotor high-voltage PMSM were established,and the solution region and boundary conditions for solving equation were given. The accuracy of the established model was validated by comparing with the measured results. On the basis of that,the wedge relative permeability is taken as 3,5,7,9 and the eddy current loss of the rotor was calculated.Each part of the motor rotor and stator temperature distribution were analyzed with magnetic slot wedge having different relative permeability values. The calculation results show that the increase of the relative permeability values of stator slot wedge,the starting torque of the motor is reduced,rotor core eddy current losses decrease,stator temperature decreases at first and then tends to be stable.