推荐一种嵌线工艺图

电机嵌线是电机生产维修中的主要工序,在工厂电机维修中,一般是凭经验或以电机绕组展开图分析嵌线工艺和嵌线顺序,这种方法不是很直观的,易产生差错。会使部分或全部返工,造成材料和工时的损失。在教学上,用展开图讲解嵌线工艺,也不十分方便。为此,在展开图的基础上画出一种专用嵌线工艺分析图,近年来用于生产、教学上,取得了很好的效果。在生产上减少了返工损失,在教学上,提高了教学吸收效果。现将工艺分析图画法提出来,向读者推荐,供参考。     

三相交流异步电机的巧用

0 引言 在生产和维修中,有时会遇到仅有单相电源,又需要三相交流电机作动力的情况,这时可将三相电机改成单相电机运行,不改变其绕组内部结构;在边远无电山区,有时遇到需用220V交流电源,可用柴油机作为原动机,带动三相电机发电,在三相电机的三相绕组中,配置合适的激磁电容器后,就可改为自激式发电机.     

国外F级3kV电机绕组修理问题及解决的措施

在国外F级3kV中型高压电机的绕组绝缘处理,基本上都采用V·P·I整浸绝缘工艺,以达到减薄绝缘厚度的目的,以电机体积小、重量轻而著称。如F级3kV等级电机定子绕组,以连续绝缘结构形式,单边对地绝缘厚度只有1mm。它主要采用了具有高机械和电性能的聚酯薄膜作增强材料,制成单面聚酯薄膜补强少胶云母材料作主绝缘。因此,绝缘处理工艺及用的绝缘材料与老的绕组结构形式相比有很大的区别。然而,修理这种类型的电机时,会存在如下几方面的问题。1.被修电机的绕组拆除困难,铁心槽较难清净,往往被拆的电机铁心槽尺寸要变小,如要按原始槽尺寸加工制作绕组,下线时会带来一定困难。2.个别绕组损坏,几乎无法采用局部更换绕组方法。要更换绕组则需全部更换。更换下来的绕组就不能再利用了。3.国外电机中所采用的以薄型的聚酯薄膜单     

火烧法拆除电机绕组的弊端及建议采用的方法

中小型电机绕组烧坏之后,需拆除烧坏的绕组,更换上新线绕组。由于电机维修工艺的要求,在下完绕组后,要浸绝缘漆烘干。这样就使得坏绕组线用冷拆法不易拆除。所以,有些单位在更换绕组时,为了图方便,采用火烧法,即用废汽油和废变压器油烧拆电机绕组,其结果使电机的性能大大降低,造成了难以弥补的损失。其一,由于燃油的温度高达200多度以上,使得被烧电机铁心的硅钢片片间     

印(冲)制绕组电机绝缘材料及绝缘制作工艺的研究

本文介绍了用作印（冲）制绕组电机主绝缘材料的耐热环氧树脂预浸玻璃布的特点和优良机电性能，介绍了几种用于不同部位的粘合剂，讨论了电机绝缘制作中必须注意的工艺问题：被粘接金属表面处理，热压工艺及有关模具设计。这几种材料及工艺方法已在印（冲）制绕组电机生产中成功运用。     

直流电机绕组质量的判断及使用寿命预测

直流电机因其具有良好的起动性能-调速性能而在工厂广泛使用.在直流电机的维修中,因对电枢绕组是否有内部短路现象判断不准确,而常出现事倍功半的结果.另外,直流电机的使用寿命与许多因素有关,但最主要的是电机绕组的绝缘水平.正确判断绕组的绝缘质量及预测电机的使用寿命,对电机的可靠运行、工厂的安全生产都有着很重要的作用.笔者在长期的工作实践中运用了一些方法和措施,在这两方面取得了一定的效果,现介绍如下.     

热塑性电机绕组绝缘及其耐气候性(综述)

热塑性电机绕组绝缘是六十年代出现的一种新的电机绝缘工艺,采用带有热塑性绝缘层的漆包线,电机绕线和嵌装完毕后直接进行烘焙后即形成一整体的绝缘结构,革除了普通电机绝缘工艺的浸渍工序,节省了浸渍材料和设备,缩短了生产周期,降低了成本。下面就绝缘结构,烘焙工艺,绝缘性能和耐气候性及技术经济性等几方面阐述热塑性电机绕组绝缘的特点。 1.绝缘结构 电磁线     

俄制造线性电机新工艺

俄制造线性电机新工艺王文娟俄罗斯专家发明了用气热喷涂铁磁体、导体、绝缘材料的方法制作线性电机的新工艺。电机绕组线圈是用粉状或细丝喷涂制成导电材料。喷涂的绕组材料密度决定它的导电率，可在制造时加以控制。该工艺能用热超导陶瓷制成绕组，并且线圈可以具有任意...     

隔爆直流电动机

本电机制成隔爆型,机壳用低炭钢板卷焊而成,定、转子绕组采用F级绝缘。电机能使用于爆炸性混合物不高于2级和C组的环境中。本文对电机规格、结构特点.材料和工艺作简单介绍。     

印（冲）制绕组电机绝缘材料及绝缘制作工艺的研究

本文介绍用作印（冲）制绕组电机主绝缘材料的耐热环氧树脂预浸玻璃布的特点和优良机电性能，介绍了几种用于不同部位的粘合剂，讨论了电机绝缘制作中必须注意的工艺问题：被粘接金属表面处理，热压工艺及有关模具设计。这几种及工艺方法已在印（冲）制绕组电机生产中成功运用。     

The improvement of the electrical insulation of high voltage electrical machines

Comparative parameters are presented for the electrical insulation systems of high voltage electric machines. Composite insulation materials produced by different manufacturers are studied. The influence of the structure and composition of electrical insulation materials on the main operation parameters (electric strength, dielectric losses, the mechanical characteristics, and resistance to thermal cycling) of the insulation systems of electric machines is shown.     

An Energy-Efficient Induction Motor with an Unconventional Electromagnetic Core

In modern power setups of autonomous objects, electromechanical converters with good mass and volume performances are used. However, the problem of lowering the specific energy parameters of electric machines remains important. This article presents new technical solutions and calculation methods for unconventional energy-saving machines with improved mass and volume performances. The electromagnetic core of machines includes a stator winding with active and front conductors of rectangular cross section. The cross section of the jumpers for connections of active and front conductors is reduced. The front conductors of the stator winding do not intersect. These measures make it possible to reduce the consumption of copper, achieving a decrease of the length of the electromagnetic core while maintaining high efficiency. It has been shown that manufacturing such multilayer wavelike windings is promising. The design of the an induction motor with a stator winding of this type has been considered. The technical features in designing electrical machines with a new stator winding are discussed. A detailed end-face scheme of the stator winding and a scheme of the sequence of conductor commutation of this winding are presented. Expressions for calculating the overhang parts of the winding are given. Results of comparison new and serial motors with a power of 75 kW are given.     

旋转电机绕组磁链的三维有限元分析

针对非正弦电压供电的旋转电机稳态或动态性能仿真,提出了一种基于三维有限元分析和网格重构的绕组磁链和端部漏电感的计算方法,根据所提出的方法,计算了一种三相12/8极开关磁阻电机的绕组端部磁链,并给出了端部漏电感随转子位置和邻近绕组电流变化的曲线族。该计算方法也可用于旋转电机或其它电磁装置的三维磁链计算。具体算例说明了考虑端部漏磁场效应的条件和必要性。     

超高压电力变压器绝缘计算

本文对SFP400000/500超高压电力变压器的绝缘进行了仿真计算.对主绝缘电场的计算应用有限元法,计算时将主绝缘电场场域划分为三个子区域,得出了各区域中的电位分布和电场强度分布,并计算了相关的绝缘裕度,找出了绝缘的薄弱环节.对纵绝缘电场,建立了绕组在雷电过电压下的电路模型,分别计算了高、低压绕组在全波和截波作用下的电位分布和梯度分布,确定了梯度最大的油道,并计算了相应油道在的全波和截波下的绝缘裕度,为变压器绝缘设计和改进提供了理论上的参考依据.     

Choosing Expert Evaluations of Diagnostic Tests of Electric Insulation for High-Voltage Electric Machines

This article provides the results of studying the influence of test voltage frequency on the dynamic parameters (dielectric losses and characteristics of partial discharges) of micaceous insulation of stator winding for high-voltage (HV) electric machines. The tests have been conducted using mockup samples of stator insulation with an artificial defect in the front area. It has been established that the low-frequency (0.1 Hz) test voltage increases the dielectric loss tangent and, at the same time, reduces the peak apparent charge of external partial discharges compared to the tests at power frequencies. The established ratios must be taken into account when choosing expert diagnostic evaluations during high-voltage electric-machine tests.     

Effect of surge voltage risetime on the insulation of low-voltagemachines fed by PWM converters

This paper investigates the repetitive surge-voltage withstand of low-voltage mush-wound machines operated on adjustable-speed drives (ASDs) using insulated gate bipolar transistor (IGBT) semiconductor technology. Historical work on surge testing of motor insulation has focused on one or more of the following aspects: (1) large horsepower motors; (2) medium-voltage form-wound motors; (3) single-shot impulse-type transients; or (4) low-voltage machines with surge risetimes >200 ns. IGBT drives can have risetimes of 50-200 ns. Thus, a new study on electrical stress of insulation systems due to the nonlinear voltage distribution of mush-wound motors when subjected to repetitive steep dV/dt square-pulse waveforms (rather than impulse wave testing) is presented. Magnitude and risetime of the repetitive ASD surge-voltage transient induced on the machine terminals is reviewed first. Next, surge propagation into the winding was investigated to identify maximum voltage stress points on the conductor insulation. Potential failure mechanisms observed at these points are then discussed. The significance of decreasing surge risetime and increasing cable lengths on internal nonlinear voltage distribution is studied with experimental results from a 7.5-hp motor with a tapped stator winding     

大型发电机组启动电气试验中的问题探讨

在发电机启动电气试验中, 要进行短路试验以检查发电机定子和转子绝缘情况。为了节省试验时间和试验费用, 可以用主变高压侧短路试验代替发电机机端短路试验。在发电机空载试验时不能做定子匝间绝缘试验, 防止损伤定子绝缘。同时, 在发电机启动过程中, 必须对机组的重要继电保护进行校验, 以确保正确发挥保护的功能。     

Reliability and statistical lifetime- prognosis of motor winding insulation in low-voltage power drive systems

Today, more and more complex power drive system (PDS) applications are being used in which an arbitrary number of inverters with different, autonomous drive frequencies are connected to a single dc bus. If long feeder cables, different inverter output circuits, and unfavorable grounding conditions simultaneously occur, then electrical oscillations with high peak values of the voltage between the motor terminals and ground may be generated. Occasionally, these can exceed the peak values of the generally better known mechanism of traveling waves [1], [2]. The complex design of recent drive systems requires more knowledge about the interaction of the components being used in the system and of the resulting effects. This knowledge forms the basis for the design of reliable drive systems. One of the major reliability topics for variable-speed power drive systems has long been the lifetime of the winding insulation system. The winding insulation system may manifest partial discharge (PD) because the electrical stress is higher for these systems than it is for drive systems that are directly connected to the line supply [1]?[4]. In the classic approach (see Figure 1) [4], [5], it is assumed that the peak voltages stressing the insulation system of the motor winding would be more or less constant and the PD inception voltage of the winding insulation would also be a deterministic value. From this, it is derived that an adequate lifetime can only be achieved by ensuring operation without PD. In case of operation with PD, the lifetime would be reduced to an unacceptable level. The approach presented in this paper considers both the generation of peak voltages, which stress the winding insulation system, as well as the associated stochastic PD inception behavior. This results in a statistically-based insulation coordination and a reliability-based economic design of the complete drive system (see Figure 2).     

核电散嵌线电机定子绝缘（H级）体系研究

现国内外生产的Ｈ级散嵌线电机多应用在民用产品上,应用在核电领域的很少。本文介绍了一种应用在核电上的Ｈ级散嵌线电机绝缘体系,为Ｈ级散嵌线电机的生产制造开辟了新路。