Effects of Winding Attachment Positions on Output Characteristics of Flux‐Modulating Synchronous Machines

The flux‐modulating synchronous machine (FMSM) is a new type of multipole SM with nonoverlapping concentrated armature and field windings on the stator. This paper compares the output characteristics of two FMSMs through finite element analysis (FEA) and experiments. In both of the FMSMs, the attachment positions of the armature and field windings are swapped. To determine the reason for the discrepancies in their output characteristics, unsaturated inductances were calculated using a d‐‐q equivalent circuit. In addition, the calculated results of the inductances were confirmed through a visualization of the leakage fluxes using FEA. The results of the study show that the synchronous inductance can be reduced by attaching the armature winding to the air‐gap side of the stator teeth and that the reduction leads to an increase in output power.     

Characteristics of hydrostatic bearing/seal parts for water hydraulic pumps and motors. Part 1: Experiment and theory

In this paper, the load-carrying capacity, power losses and stiffness of disk-type hydrostatic thrust bearings including the case of eccentric loading are discussed theoretically. The numerical analysis method is established based on a two-dimensional elastohydrostatic problem with an elastic deformation model, which is extended to adapt it for a non-axisymmetric load acting on the thrust bearing. The bearing is made of a combination of stainless steel/stainless steel and stainless steel/plastics. For the elastic materials, the maximum stiffness derived from, i.e., minimum film thickness is, larger than that of the rigid material in the range of a large ratio of pocket pressure and a hydrostatic balance ratio of over unity, which is defined as the ratio of the load to the maximum hydrostatic load-carrying capacity. The maximum load-carrying capacity and minimum power loss can exist in the domain of the hydrostatic balance ratio over unity for the case of the bearing consisting of elastic/rigid materials, in comparison with that composed of the same rigid materials. For the case of water, the power loss due to leakage flow is slightly larger but that due to frictional torque is much smaller than that in the case of hydraulic oil. Then, the total power loss is much smaller than that of hydraulic oil.     

超声电机环形定子驻波的扭曲和旋转

超声电机环形定子上的驻波变形和振型旋转的现象在实验中被观察到,行波和类行波出现在单相激励情况下。该文讨论了单相激励行波和类行波的成因,当环形定子具有一个非轴对称结构时,同形退化模态不再存在,代之以两个近频模态,由于结构阻尼对这两个模态贡献不同,使得响应出现相位差,行波出现。类行波实质上不是行波而是驻波的扭曲,只是看起来像行波。     

步进电机细分及其在光电测径系统中的应用

叙述了步进电机的细分技术及其测长原理。作为一种测长手段应用于工件直径测量系统中，为提高步进电机细分测长的精度，系统采用了软件补偿的办法，应用光电定位和ＭＣＳ—５１单片机实施控制，构成一种测量范围在１～１００ｍｍ，精度较高，效费比高的光电测径系统。     

步进电机在红外系统扫描机构中的应用

介绍了在红外系统中，采用步进电机作为扫描机构驱动元件，以Ｄ／Ａ数模转换器作细分方式的定频脉宽调制驱动方式，实现微机控制下的扫描机的构步距均匀稳定，满足红外系统分辨率的要求。     

铝箔轧机开卷和卷取电机的谐波分析

本文结合一台2000mm铝箔轧机的电气传动系统，介绍铝箔轧机开卷、卷取电机的谐波计算方法，并分析铝箔轧机开卷、卷取的谐波特点。     

双极性步进电机细分驱动器的设计与实现

论述了一种双极性步进电动机驱动器的工作原理，该驱动器能较好地改善步进电动机的运行性能，具有实用性强，结构简单，成本低的优点。针对实际调试中出现的问题进行分析后，提出了对策；最后给出了试验结果。     

削弱永磁同步伺服电机齿谐波电势方法的比较

讨论了四种结构修理工削弱永磁同步伺服电机齿谐波电势的影响，并对他们的效果进行了比较。     

无轴承异步电机转子磁场定向MRAS转速辨识

为了准确辨识无轴承异步电机的转速,提出一种改进转子磁链估算电压模型。以改进转子磁链估计模型为基础,构建了无轴承异步电机的转子磁场定向模型参考自适应(MRAS)无速度传感器矢量控制系统,并通过Matlab/Simulink进行了系统仿真分析。仿真结果表明:基于所提出的转子磁链改进模型,可有效避免纯积分环节初值和累计误差等影响,获得较高的转速辨识精度。所提出的转子磁链辨识模型和MRAS无速度传感器矢量控制系统是有效和可行的。     

基于LS-SVM逆系统的无轴承异步电机解耦控制

无轴承异步电机具有非线性、多变量和强耦合的特点,要实现电机稳定悬浮和旋转运行,必须对其进行非线性动态解耦控制。为了克服逆系统方法精确建模难的局限性,采用基于最小二乘支持向量机(LS-SVM)α阶逆系统方法对无轴承异步电机进行动态解耦控制的研究。首先利用最小二乘支持向量机辨识出无轴承异步电机的逆模型,然后将它串联在原系统前,将无轴承异步电机解耦成四个独立的伪线性子系统-2个径向位移子系统、一个速度子系统和一个磁链子系统。为保证鲁棒性能,最后对解耦后的系统采用非线性内模控制策略。研究表明,LS-SVMα阶逆系统方法能够实现无轴承异步电机径向悬浮力和旋转力之间的动态解耦控制,控制系统具有良好的静态和动态性能。