副绕组串电容的直线感应电动机

提出一种副绕组串电容以提高直线感应电动机功率因数和静推力的方法，并进行了理分析和试验研究。结果表明：在电机尺寸和原材料消耗不变的前提下，此方法比Ｈｏｌｍｅｓ方法在提高直线感应电动机静推力方面有明显效果。     

高温超导直线感应电机的优化设计

详细讨论了高温超导直线感应电机的结构设计和初级绕组排列方式,给出了高温超导带材临界电流和背景磁场的关系曲线。采用Maxwell有限元电磁分析软件对高温超导直线感应电机进行了详细的电磁分析,并对初级绕组匝数、初级铁心槽高和初级铁心槽宽等关键参数进行了参数扫描和优化,分析了它们对电机电磁力、初级槽漏磁通和电机临界电流的影响,提出了高温超导直线感应电机的优化设计方法。根据得到的高温超导直线感应电机优化设计参数制造了一台完全相同的铜绕组实验样机,测试了样机在不同电流和速度下的推力,对比相同条件下得到的有限元电磁仿真结果,可以得到一个修正推力仿真结果的系数,这个系数对研究不同电机参数的电机推力很有意义。     

初级永磁型游标直线电机绕组连接及其电磁特性比较

初级永磁型游标直线(LPPMV)电机具有低速、大推力输出特性,特别适用于直线直驱系统。设计合理的绕组连接方式可有效改善电机性能。首先根据电机的运行原理,针对一台6/2极LPPMV电机提出了4种不同的绕组连接方式;其次通过有限元法,比较了LPPMV电机在不同绕组连接方式下的特性,包括空载感应电动势、电感,并在相同铜耗条件下计算了绕组的总质量、电枢电流、推力、铁心磁通密度以及铁耗等,以此得到了不同绕组连接方式下电机的运行效率;最后折中选择了一种绕组连接方式,制造了样机,并通过实验验证了电机的性能。     

用于精密加工的三相磁通切换永磁直线电机的研究与分析

数控机床常用的驱动方式为旋转电动机+齿轮或皮带等中间传动装置,但是这种方式存在有很多的缺点,如摩擦、反向间隙等都会直接影响并限制数控机床的加工精度。该文提出一种用于精密加工的三相磁通切换永磁直线电机,该种直线电机继承了永磁磁通切换电机和直线电机的优点,由于它可以采用直接驱动的方式而不需要中间传动环节,因此可以显著提高数控机床的加工精度。首先,文章给出了该电机的基本结构并分析了其工作原理;其次,基于有限元法对电机进行仿真和分析,并研究其特性,如磁场分布、空载反电动势、绕组磁链、绕组电感和电磁推力等,通过对仿真结果分析发现绕组磁链和反电动势的波形本质上均为正弦波;最后,对不同永磁体厚度、气隙、电流和速度下的电磁推力进行比较和分析以研究推力随这些参数的变化情况。     

主、副绕组串联电容电动机的特性分析及其设计

本文使用等效两相电机的数学模拟法导出主、副绕组串联电容电动机的特性计算式。然后分析了其运行性能及其与通常电容电动机特性间的关系。这种主、副绕组串联接线方式的电容电动机,适宜于设计成小机座的微型电容电动机,可改善电机制造的工艺性,又可提高电机的运行可靠性。     

中速磁浮无铁心永磁直线同步电机的结构优化

中速磁浮列车采用单边长初级无铁心永磁直线同步电机(IPMLSM)作为牵引电机，因为这种电机具有结构简单、运行平稳、无轮轨摩擦以及法向吸引力接近于0等优点，但是由于该电机定子无铁心，导致其推力密度较小，且永磁材料使用过多及定子绕组沿轨道长距离铺设，使电机效率进一步降低。为了提高电机性能，在IPMLSM基本结构的基础上，提出一种新型永磁体装配结构，可提升电机推力密度；并根据长定子IPMLSM绕组的特点，优化绕组导体截面，获得适用于中速磁浮列车IPMLSM定子绕组导体的宽与高之比，进一步提升电机的推力密度。最后，制作IPMLSM小型样机实验装置，对比实验结果验证了所提改进结构的优越性。     

双交替极横向磁通直线电机的基础研究

提出一种新型双交替极横向磁通直线电机。该结构集成了两种交替极横向磁通电机拓扑,位于初级和次级的永磁体产生的磁通以相同的方向与绕组相交链,通过共用部分铁心和绕组,充分利用了电机内部空间,提高了材料利用率,增大了电机推力密度。通过分析电机内磁场分布,建立电机磁网络拓扑,并计算绕组磁链,推导电机电磁力表达式。通过有限元对理论分析进行验证,得到电机磁链、反电势及电磁推力分布波形。研制一台实验样机,测量样机的反电势,验证新结构电机的原理与性能。     

新型高效低谐波绕组设计

介绍一种新型高效低谐波绕组,初步分析了该绕组磁势谐波的特点。采用有限元方法进行电磁场分析,表明新型高效低谐波绕组电机可以有效降低电机谐波,改善电机磁场分布。通过样机制造和电机试验,证实了新型高效低谐波绕组电机杂散损耗大幅度减小,电机温升显著降低。     

电机绕组制造装备行业分析(上)

电机制造业是我国工业领域的基础性产业,电机产品是关系到各行各业自动化的重要基础产品,其中电机绕组为电机核心部件,素有"电机心脏"之称。因此电机绕组生产制造设备是电机诸多生产设备中关键的专用生产设备。电机绕组制造装备的质量及性能水平的提高和发展,将直接影响国民经济的发展水平。本文通过对电机绕组制造装备行业发展现状、存在问题进行分析,并对未来发展趋势做出预测。由于篇幅所限将分上、中、下三部分刊登,全文详见中国电器工业协会网站市场透视栏目。     

圆筒永磁直线电机设计及推力波动研究

圆筒型永磁直线电机无需中间传动装置便可实现直线运动,使系统结构简单、响应快,但其存在推力波动大的问题。为了减小电机推力波动,提高电机推力性能,本文重点从初级铁心长度、极弧系数和闭口槽的使用3个方面对电机结构进行了分析,研究其对电机推力的影响。最终确定了圆筒直线电机的设计方案,并制造出样机,所得结果为圆筒型永磁直线电机设计提供了理论依据。     

Surface induction motor for two‐dimensional drive

In this paper, the authors propose an induction type surface or planar motor for smooth two‐dimensional drive including rotating operation. The secondary member is composed of the flat conducting plate without directional qualities and the back‐iron plate as secondary yoke. The primary member is composed of the torodial core and the armature winding which can supply the current in every coil embedded in a slot. For the rotating drive, all the coils are used and the same rotating magnetic field as an ordinary rotating motor is generated. For the linear drive, a partial rotating field is generated in the direction of movement in each region separated into two groups every half of toroidal core. For the armature winding, two types of methods are used which are a ring‐winding supplied current at each slot and a double‐layer‐winding supplied current to each coil. The two‐dimensional electromagnetic analysis in Cartesian coordinate system is shown for the analysis, in which an effect of circular shape is considered as an edge effect. The thrust and normal force characteristics at standstill were confirmed practically by using test machine. It was cleared that the surface motor had high transformation rate of about 79% for thrust in spite of the circular shape. © 2000 Scripta Technica, Electr Eng Jpn, 130(4): 107–115, 2000     

A LINEAR TRANSFER FIELD MACHINE FOR ASYNCHRONOUS MODE OF OPERATION

ABSTRACT

For the first time, this paper describes a working model of a novel linear transfer field machine along with an equivalent circuit analysis method for the asynchronous mode of operation In the sinusoidal steady-state. The machine is found to have a thrust-speed characteristic like unto that of the flat linear induction machine with a conducting sheet secondary. Analysis of performance is made for values of speed across the range from standstill to synchronous speed. Laboratory measured data are compared with calculated values for standstill operation.     

基于改进静止频率响应试验的同步电机参数辨识

针对同步电机参数辨识问题,以全电流为状态变量,研究同步电机d、q轴磁链与定子电流及励磁电压的关系,建立电机的数学模型。通过分析静止频率响应试验曲线,获得不同频率下各测试参数的增益和相位,替换d、q轴电磁参数特性传递函数方程中的相关部分,简化电机数学模型及其状态空间方程。基于励磁和定子回路开路时电机状态的分析结果,改进数据处理过程,辨识电机参数,对比采用其它方法测取的结果,有较好的一致性,所提参数辨识方法的有效性得以验证。     

基于次级错齿的C型铁心双边直线永磁开关磁链电机

直线永磁开关磁链电机(LFSPM)适合长次级直线驱动场合,这是由于永磁体和电枢绕组都在短初级,而长次级结构简单可靠性高。很多应用场合都要求电机具有高推力,但往往也需要低的推力脉动。为此,对1台双边C型铁心的直线永磁开关磁链电机(DSLFSPM-C)进行研究和改进。利用有限元软件先对电机进行推力优化,然后为了在不影响平均推力的情况下有效地减小推力脉动,分别利用次级错齿和端部永磁体两种结构对电机进行了改进。分析结果表明,改进后的DSLFSPM-C具有相对较低的法向力、高的推力输出以及较低的推力脉动。     

Development of a deceleration control system for a winding machine based on a microcontroller

The development of an automatic deceleration system for a winding machine in a siderurgy factory is presented in this paper. The proposed system controls the speed of a winding machine in order to obtain the optimum stop point in terms of security and fast production. The system is based on a microcontroller and an extremely simple hardware. The system has been tested for two years and results evince a very good mean time between failures.     

内嵌式永磁同步电机转子初始位置检测(英文)

针对内置式永磁同步电机的无感器运行问题,提出一种转子初始位置估计方法。通过对内嵌式永磁同步电机的定子绕组施加合适的电压脉冲,检测未通电相的端电压就可以获得转子的位置信息。利用磁饱和效应对凸极性的影响来区分南北极,从而区别2个稳定区,转子初始位置估计方法的分辨率为30°电角度。以DSP控制的永磁同步电机系统为试验平台,对所提出的方法进行了试验验证及试验结果分析,结果表明,提出的方法能够可靠而有效的估计初始转子位置。     

Prediction of starting performance of PM motors by DC decay testingmethod

This paper presents a method to predict the direct- and quadrature-axes operational impedances and starting performance of permanent-magnet (PM) motors by a simple standstill response testing method using a small-capacity DC power supply unit. In this method, not only the starting performance but also the direct- and quadrature-axes synchronous machine constants (synchronous, transient, and subtransient reactances) and equivalent circuit constants are calculated. This proposed strategy, tentatively named the DC decay testing method, is carried out on a 3.7-kW 200-V 22. A 100-Hz four-pole interior PM motor with a damper winding. The results measured by on-load tests and those predicted by the proposed method on starting performance demonstrate the validity and usefulness of the proposed method     

Detection of induction machines rotor faults at standstill using signals injection

The main topic of this paper is to examine the feasibility of detecting the rotor faults of induction machines by performing standstill tests. It has been shown that by feeding the machine with special excitation signals such as discrete interval binary sequence (DIBS) and multisine, it is possible to excite with low-frequency resolution the faulty modes by analyzing the stator current and the stray flux measured by an external flux sensor. This method can be used for quality control just after manufacturing the rotor and mounting it within the stator frame. The proposed technique is fully general and can be applied to a three-phase squirrel-cage induction machine at standstill. Experimental measurements are made both on healthy and faulty machines and the comparison gives a difference in the external flux and stator current signatures which are basically the most commonly used methods for rotor fault detection.     

The Similarities of Electrical Machines under Transient Conditions

This paper draws attention to the considerable similarity that exists in electrical machines when operating in the transient mode. An analysis is made of a salient pole synchronous machine, which has a damper winding. Using these equations it is possible to deduce the equations of other types of machines. In this way the similarities are highlighted.