一种叉车用永磁电机铁耗分布特点及其计算

Distribution characteristics and calculation of iron loss of a permanent magnet motor for forklift

内置-表贴式异向旋转永磁电机是一种内外转子同速异向旋转的新型电机,其定子铁芯磁场为脉振磁场,其定转子磁密的分布情况与永磁电机存在较大的区别,而铁耗的精确计算是电机设计及优化的关键。为了精确计算新型电机的铁耗,将定转子铁芯分为五个区域,分别研究铁耗的分布情况,并将磁密分解为径向磁密与切向磁密。在此基础上,利用傅里叶分解的方法,建立新型电机的铁耗精确模型,利用实验的方法拟合出铁损系数,研究转速、气隙长度及槽口宽度对铁耗的影响。结果表明,合理的槽口宽度与气隙长度可有效减小新型电机的铁耗,提升电机的效率。

The built-in surface-mounted counter-rotating permanent magnet motor is a new type of motor with inner and outer rotors rotating at the same speed and counter directions.The stator core magnetic field is pulsating magnetic field.The distribution of stator and rotor magnetic density is quite different from that of permanent magnet motor.The accurate calculation of iron loss is the key to the design and optimization of the motor.In order to accurately calculate the iron loss of the new type of motor,five areas of stator and rotor cores are divided to facilitate the distribution study of iron loss respectively,and the magnetic density is divided into radial magnetic density and tangential magnetic density.On this basis,an accurate iron loss model of the new type motor is established by Fourier decomposition method and iron loss coefficient is fitted by experiments,and the effects of rotating speed,air gap length and notch width on iron loss are studied.According to results,reasonable slot width and air gap length can effectively reduce the iron loss of the new type motor and improve motor efficiency.