高精度直流永磁测速发电机输出纹波误差分析

对一台纹波精度达0.1％的稀土永磁直流发电机的纹波误差产生机理进行了定性的分析与计算，并论述了纹波误差的组成。经过分析得出，纹波误差主要由原理性因素和工艺性因素引起。原理性因素包括绕组离散分布、齿槽效应、极宽和槽数的配合、磁场波形；工艺性因素包括气隙偏摆、磁钢充磁及装配偏差、导体分度偏差、电刷工艺性偏差和电刷噪音。计算表明，众多因素中，齿槽效应及工艺偏差是造成纹波偏差的主要原因。

EMF ripple analysis of high-accuracy DC low-speed permanent magnetic tachogenerators

A high-accuracy DC tachogenerator can be used to measure the velocity of the low speed motor system as a feedback signal. The ripple error of a DC tachogenerator with 321 slots and 16 permanent magnetic poles is only 0.1%, which consists of two main parts: (1) deviation from the theorem ;(2) deviation from the technology. In this article we concluded that among all reasons above, tooth and slot influence as well as the deviation from the technology are the most important factors which affect the accuracy of the motion.