For Propulsion Applications It Is Possible to Utilize Both the Torque Output of the Rotor and the Reactional Torque Acting on the Stator of the Driving Electric Motor by Linearizing the Stator

This paper presents a novel idea of utilizing the reactional torque of the conventional electric motor as a linear output for propulsion in addition to the conventional torque output of the rotor. The idea is demonstrated by a theoretical proposal of linearizing the stator of one of the most used motors in Electrical Vehicles and Hybrid Vehicles. The proposed Linear Stator Motor is a simple modification without involving any functional change of the conventional motor. Though theoretical, the indicated possible input energy saving of more than 75% as compared to the conventional motor is no surprise, as by linearizing the stator, an almost equal linear propulsion output is added to the conventional rotor output. In addition to this remarkable saving in input energy, the proposed Linear Stator Motor that suits all types of vehicles, can maintain propulsion without the need for a mechanical transmission system. Also, in the case of watercraft and aircraft vehicles, no external mechanical propulsion drive system is required. It is just an internal force that can push the vehicle forward, backward, or laterally, while the conventional rotor output can be utilized for energy recovery by driving a DC generator.

Rotor Design and Finite Element Analysis of Traveling Wave Rotaty Ultrasonic Motor

The dynamic transfer mechanism of the traveling wave rotary ultrasonic motor rotor-stator’ s contact surface is studied in the paper and the key parts stator and cone flexible rotor of ultrasonic motor are designed.The three-dimensional contact model and finite element model considering the radial sliding between the rotor and the stator are established. The relation between the stator surface particle that amplitude frequency characteristics,resonance speed,radial displacement of ultrasonic motor and the tooth height are analyzed. Mass point radial relative displacement of contact surface between the cone flexible rotor,flexible rotor and the stator are contrasted. The cone flexible rotor is better placed on the surface of the stator tooth through its elastic deformation is interpreted. The cone flexible rotor reduces the radial slip between the stator and the output efficiency of ultrasonic motor is improved. The displacement trajectory of the stator surface is synthesized in a row wave cycle. The method of the stator mass point elliptical motion drives the rotor rotation is verified.

Analysis of Temperature Rise in High-Speed Permanent Magnet Synchronous Traction Motors by Coupling the Equivalent Thermal Circuit Method and Computational Fluid Dynamics

To solve the problem of temperature rise caused by the high power density of high-speed permanent magnet synchronous traction motors,the temperature rise of various components in the motor is analyzed by coupling the equivalent thermal circuit method and computational fluid dynamics.Also,a cooling strategy is proposed to solve the problem of temperature rise,which is expected to prolong the service life of these devices.First,the theoretical bases of the approaches used to study heat transfer and fluid mechanics are discussed,then the fluid flow for the considered motor is analyzed,and the equivalent thermal circuit method is introduced for the calculation of the temperature rise.Finally,the stator,rotor loss,motor temperature rise,and the proposed cooling method are also explored through experiments.According to the results,the stator temperature at 50,000 r/min and 60,000 r/min at no-load operation is 68℃ and 76℃,respectively.By monitoring the temperature of the air outlets inside and outside the motor at different speeds,it is also found that the motor reaches a stable temperature rise after 65 min of operation.Coupling of the thermal circuit method and computational fluid dynamics is a strategy that can provide the average temperature rise of each component and can also comprehensively calculate the temperature of each local point.We conclude that a hybrid cooling strategy based on axial air cooling of the inner air duct of the motor and water cooling of the stator can meet the design requirements for the ventilation and cooling of this type of motors.

Fundamental Design and Analysis of a Novel Bipolar Transverse-Flux Motor with Stator Permanent-Magnet Excitation

In this paper,a novel bipolar transverse flux motor with stator permanent magnet excitation is proposed based on the summary and analysis of the transverse flux motor and stator permanent magnet motor research achievements in recent years.It has been shown that the motor realizes the bipolar winding flux through the detailed analysis.The motor can be used as an inwheel motor in electric vehicles because of its external rotor and permanent magnets mounted on the stator radial surface.Secondly the basic structure and working principle of the motor are introduced.Then the relationship between the motor power and its dimensions is deduced.Thirdly the 3 dimensional finite element method(3D FEM)is used to analyze the static and transient characteristics,including the no-load magnetic field distribution and winding back EMF.Finally a three-phase 600W prototype has been made and the experimental analysis is carried out.

Investigation in Determining the Relative Position between Stator and Rotor of a PMSM in Electromagnetic Field Calculation

When designing a universal finite element software for analyzing a permanent magnet synchronous motor,the relative position of the stator and rotor remains unknown.However,determining the relative position is a precondition for electromagnetic field calculation.Through analyzing the basic relationship of variables in a synchronous machine,the characteristics of an air-gap-resultant electromotive force and an inner power angle under a special inner power factor angle are obtained.A method similar to inverse problem solving is proposed.A series of electromagnetic field calculation under different armature current initial phase angles are carried out,and through searching the field of a special inner power factor angle,the relative position of the rotor and the stator can be determined subsequently.

Eddy Current Losses in Solid Pole Shoes in a Two-Pole Permanent Magnet Motor

The aim of this paper is to present the eddy current losses in solid pole shoes in a permanent magnet two-pole electric motor. In the presented paper, the authors have chosen to work with three different analytical models, Carter’s theory, Gibb’s theory and Lawrenson’s theory, each with different degree of accuracy and simplifications. The results from the analytical models all present relatively low eddy current losses, giving the designer valuable arguments to utilize solid pole shoes, as a rotor with solid poles is from a construction point of view a more suitable choice, increasing the mechanical stability and reducing the production cost, compared to the laminated design.

基于代理模型的双气隙混合转子低速大转矩同步电机优化设计

为解决常规低速大转矩电机普遍存在体转矩密度低、永磁体用量多等问题,提出了一种双气隙混合转子低速大转矩同步电机拓扑结构。然而,该种电机结构相对复杂、设计参数多、优化难度大,对此提出了一种基于代理模型的双气隙混合转子低速大转矩同步电机高效优化设计方法。首先,以提高输出转矩与降低转矩脉动为优化目标,对电机的参数进行敏感性分析,实现了在保证代理模型精确度的基础上精简优化变量。然后,为提高该种电机多目标优化设计的精确度和效率,同时缩短优化周期,提出了一种序贯子空间与模式搜索算法相结合的优化算法对电机进行优化处理。最后通过有限元仿真与实验方法验证了所构建代理模型的精确性、合理性和优化方法的有效性、先进性。

非晶电机定子铁芯的制备工艺及最新研究进展

非晶合金凭借优异的综合软磁性能,尤其是在高频下有着极低的损耗而在高速电机领域备受关注。概述了非晶电机的优势和类型,综述了非晶定子铁芯的关键制备工艺,对比了径向叠压和轴向卷绕铁芯、模块拼接和整体成型铁芯以及有槽和无槽铁芯的各自优缺点。从退火处理、浸胶固化以及加工成型方式的角度总结了上述制备工艺对非晶带材和铁芯的性能影响。最后,结合非晶电机的最新研究进展,分析了当前非晶合金应用于电机定子铁芯存在的问题,并对未来非晶电机定子铁芯加工方法的发展进行了展望。

一种定子单绕组无轴承开关磁阻电机的转子位移控制方法

提出了一种用于定子单绕组无轴承开关磁阻电机(Bearingless switched reluctance motor,BLSRM)的转子位移控制方法。首先介绍了定子单绕组无轴承开关磁阻电机的基本结构和工作原理,基于等效磁路法建立悬浮力和刚度的数学模型。其次,建立了转子动力学模型以获取悬浮力与转子位移间的关系模型。最后,设计了一台实验样机并在电机上进行悬浮控制实验。实验结果验证了所提控制方法的有效性。

基于定转子槽结构协同优化的交流牵引电机电磁降噪优化设计方法

针对交流牵引电机存在电磁噪声较大的问题,提出一种基于定转子槽结构协同优化的交流牵引电机电磁降噪优化设计方法。分析了交流牵引电机电磁噪声的产生机理,阐述了在电机定转子槽底部开槽降噪的基本原理与具体设计方法,并对开槽位置与槽口尺寸进行了参数优化研究。最后对降噪效果进行了仿真验证,同时与传统降噪方法进行了对比分析,结果表明采用所提电磁降噪优化设计方法对交流牵引电机定转子槽结构进行优化处理后,在保证其效率有所增加的情况下,电磁噪声得到了显著下降,因而取得了较好的降噪效果。

定子铁心焊缝数量及尺寸对永磁同步电机性能的影响

本文基于工程实践,首先仿真分析了焊槽尺寸形状、焊槽位置和焊槽数量对于6极54槽新能源汽车用永磁同步电机三相感应电势不平衡度的影响;其次仿真分析了在不同定子槽数和电机极数下,电机三相感应电势不平衡度的变化规律;最后进行了样机制作和测试验证。通过仿真分析和试验验证,指出了对于6极54槽新能源汽车用永磁同步电机,焊槽的宽度和深度均会影响电机的三相感应电势的不平衡度,电机的三相感应电势的不平衡度与焊槽的尺寸成正比例关系;同时还指出了对于永磁同步电机,从减小三相感应电势不平衡的角度,定子焊槽的数量不适宜选用极数的整数倍;此外还指出了电机的三相电压和电流的平衡度与电机的扭矩输出和运行效率的对应关系。

高压自起动永磁同步电动机的设计及实验研究

该文主要探究高压自起动永磁同步电动机的设计要点,并对其性能进行实验探究。定子设计主要包括合理选择定子冲片以及确定定子槽数,同时将定子绕组的端部连接形式改为“Y”接形式,避免谐波在定子绕组之间产生环流。转子设计主要包括选择合理的转子槽型,以及采用内置式磁路结构,并通过加装隔磁磁桥的方式,避免磁路结构发生漏磁现象。结合设计方案改造电动机,并进行温升实验和振动实验。结果表明,该电动机在满载时效率稳定在98%左右,功率因数达到0.997,在稳态时的设计性能较好。在风机正常工作情况下,绕组与轴承等可以很快达到热平衡状态,热稳定性良好。电动机振动较小,运行平稳,综合性能良好。

某型轮毂外转子永磁电机定转子合装工装的设计

针对某型轮毂外转子永磁电机的特殊结构,分析了电机定转子合装工艺的难点,并提出了相应的解决方案。设计了一种定转子合装工装,通过现场样机组装及试验验证了方案的可行性。

一种船舶推进的双定子单转子场调制超导电机

双定子单转子永磁同步电动机存在转矩脉动大、反电势谐波含量丰富的缺点。为了提高电机的电磁性能,提出了一种船舶推进的双定子单转子场调制超导电机。该模型将超导材料代替调磁环中的环氧树脂,且在外定子开辅助槽。利用遗传算法对电机的关键参数进行优化。与传统模型相比,提出模型的输出转矩提高了4.36%,转矩脉动降低了5.12%。

利用旋变软解码研究分析车用永磁同步电机定转子同心度

本文提出了一种新能源车用永磁同步电机定转子同心度的检测方法和检测原理,通过该方法可以检测永磁同步电机定转子的同心度偏差,同时还对检测原理进行了分析和研究。本文介绍的检查方法基于旋变软解码原理,能够精准测量电机定转子的同心度,并根据检测方法设计了实验平台和检测流程。试验台特别设计了电机控制器和电驱动系统,配备了实时测量和标定功能的软件应用界面,使得检测流程更为直观和高效。经过实验验证,该检测方案展示了高稳定性和可靠性,测量结果的误差范围小,证明了其精准度和实用性。

高速永磁电机定子铁心损耗的分析与计算

为了提高高速永磁电机定子铁心损耗计算的准确性。首先,通过分析高速永磁电机定子铁心的磁化特性,给出了定子铁心的磁化轨迹图。然后,根据得到的磁化轨迹图对铁耗模型进行了改进,并依据有限元法验证了该解析法的准确性。最后,对比了样机铁心损耗的测试值,给出了优化后的新铁耗计算模型。样机定子铁耗计算模型的优化为高速永磁电机系列化设计提供了有力参考。

异步电动机的转子断条问题研究

讨论了异步电动机转子断条故障的特征机理,介绍了通过定子电流监测进行故障诊断的方法。概述了鼠笼式异步电动机转子断条故障可能由机械应力、过载电流和设计缺陷等因素引起,并强调了这种故障对电机性能的负面影响,包括转速异常、噪声增大和潜在的安全风险。提出了通过监测气隙磁场变化和定子电流频谱分析来诊断故障的方法。在正常情况下,电机磁动势平衡对称,而转子断条破坏了这种对称性,导致转矩波动和平均转矩下降。通过对定子电流进行频谱分析,检测到特定的谐波分量。提出结论,尽管传统理论侧重于基波的影响,实际上其他定子电流成分也参与了谐波的生成,并且可以通过监测特定频率的谐波分量来判断转子是否存在断条故障。

双转子柱体超声波电机运行机理与实验研究

环形行波型超声波电机小直径条件下,输出性能逐渐失去低速大扭矩的特点。而柱体弯曲振动超声波电机是靠圆柱定子端部的摇头振动并通过摩擦来驱动转子的,定子的直径越小,摇头振动的幅值越大,因而,小直径时更能显示出这种电机的优越性。该文阐述了双转子柱体弯曲振动超声波电机的运行机理,证明了定子表面质点运动轨迹为一椭球;利用ANSYS有限元软件分析了电机的弯曲振动模态;用阻抗特性分析仪分析了电机的阻抗特性和相位特性;制作了直径为20mm、有两个转子的柱体弯曲振动超声波电机, 并对其输出特性进行了测试,最大转矩达0.16Nm、最高转速为220r/min。

一种新型圆柱定子3自由度球形压电超声电机

3自由度超声电机利用圆柱定子的 3种同频共振模态 ( 2个正交的弯曲摇摆振动和 1个纵向振动 ) ,两两分别叠加、合成 ,通过摩擦驱动球转子分别绕 3个轴旋转 .根据这一原理可将该电机改装成多自由度直线电机 .通过有限元方法设计定子的结构和模态 ,利用阻抗测试方法测得的定子共振频率、模态与设计相符 ,同时测量了球转子绕 3个轴的转速特性 .为了提高 3自由度圆柱超声电机的定转子传动效率 。

高速电机用非晶合金定子铁心的损耗特性研究

采用热处理后浸漆、固化、切割的方法将非晶态合金带材制作成电机定子铁心,研究了尺寸相同的非晶合金定子铁心与硅钢定子铁心的磁性能。结果表明,在频率为1 kHz、磁通密度为1.0 T时非晶定子铁心的损耗为42W/kg,在相同测试条件下,硅钢定子铁心的损耗为102 W/kg,非晶定子铁心在1 kHz、1.0 T时的损耗比相同尺寸的硅钢定子铁心的损耗降低了58.8%。