面装极宽调制式永磁电机齿槽转矩研究

为了抑制面装式永磁电机的齿槽转矩,在对比了抑制齿槽转矩常用方法的基础上,提出永磁体正弦极宽调制方法,结合实例样机设计面装式永磁电机永磁转子极宽调制结构、尺寸和参数.利用有限元方法对传统面装式永磁电机和极宽调制式永磁电机内部电磁场进行计算,得到2种结构的永磁电机气隙磁场波形和齿槽转矩特性曲线;与传统面装式永磁电机相比,极宽调制方法可使气隙磁场波形正弦化程度提高38.98%;研制传统面装式永磁电机和极宽调制式永磁电机样机,并设计构建一个由角度传感器、扭矩扳手和样机电机组成的齿槽转矩实用测试系统,对2种不同结构样机的齿槽转矩进行了实验检测.对于2种实例样机,与传统面装式永磁电机相比,有限元分析计算结果和实验结果表明,正弦极宽调制方法可以使齿槽转矩分别降低30.5%和30.9%,可见永磁体正弦极宽调制方法是一种抑制面装式永磁电机齿槽转矩的有效方法之一.

Study on the cogging torque of surface-mounted permanent magnet motor with pole-width modulation structure

In order to suppress the cogging torque of surface-mounted permanent magnet motor,a permanent magnet sinusoidal pole-width modulation method was proposed based on contrast of various methods which is commonly used to suppress cogging torque.Combined with the prototype structure,the size and parameters of the surface-mounted permanent magnet motor with pole-width modulation rotor were designed.The air gap magnetic waveform and the cogging torque characteristic curve of the traditional surface-mounted permanent magnet motor and pole-width modulated permanent magnet motor were obtained by using finite element method to calculate the electromagnetic fields of these two permanent magnet motor structures respectively.The pole-width modulation method can improve the sine degree of the air-gap magnetic field wave by 38.98% compared with the traditional surface-mounted permanent magnet motor.Two prototypes were developed for these two motors respectively.The cogging torque experiments of these two motors were done by a system consists of angle sensor,torque wrenches and permanent magnet motor.As far as the two prototypes were concerned,the finite element analysis and the experimental results showed that the sinusoidal pole-width modulation method decreased the cogging torque by 30.5% and 30.9% respectively,compared with the traditional surface-mounted permanent magnet motor.The result indicates that the permanent magnet sinusoidal pole-width modulation method is an effective method for suppressing the cogging torque of surface-mounted permanent magnet motor.