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由于磁通反向式电机固有的结构特点,其齿槽转矩相对较大,本文在分析其齿槽转矩产生机理和计算方法的基础上,对现有齿槽转矩削弱方法进行了深入分析和总结,找出了几种行之有效的削弱方法,为齿槽转矩削弱技术的实际应用和进一步研究提供借鉴。 相似文献
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针对双定子磁通反向电机存在齿槽转矩过高,引起噪声振动的问题,采用阶梯形转子代替传统转子来削弱齿槽转矩.基于磁共能法,推导了双定子磁通反向电机齿槽转矩的解析模型,解释了阶梯形转子抑制齿槽转矩的原理.应用有限元方法,分别研究了各层阶梯块极弧系数对齿槽转矩和反电动势的影响.以齿槽转矩最小、反电动势谐波最小、反电动势幅值最大为... 相似文献
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轴向磁场磁通切换永磁电机齿槽转矩分析 总被引:3,自引:0,他引:3
为了有效削弱轴向磁场磁通切换永磁电机的齿槽转矩,采用能量差分法,建立了该种电机齿槽转矩的解析表达式,针对表达式中的电机结构参数,利用全场域三维有限元法.分析了一台三相12/10极轴向磁场磁通切换永磁电机在不同结构参数下的齿槽转矩,得到当定子齿宽、定子槽口宽与永磁体磁化厚度均占内径圆弧7.5°,转子齿宽占内径圆弧10.5°,且为准扇形齿时.该电机的齿槽转矩最小;在定子轭部铁心不饱和的情况下,齿槽转矩随定子厚度减小而减小,而受转子厚度的影响较小.综合考虑电机不同结构参数对齿槽转矩和感应电势的影响,得到了削弱轴向磁场磁通切换永磁电机齿槽转矩的有效方法,有效地改善了该电机的运行性能. 相似文献
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横向磁通永磁电机(TFPMM)因结构特殊,存在功率因数低、转矩脉动大等问题,需要改进控制算法来降低电机的转矩脉动,改善控制系统性能。在传统的直接转矩控制(DTC)基础上提出空间矢量调制(SVM)的DTC策略,以改善传统控制策略中电流、磁链控制不精确,转矩脉动大的问题。针对TFPMM齿槽转矩比较大的问题,将电机齿槽转矩拟合成电角度的表达式,补偿到转矩观测器输出端,使转矩观测器能观测齿槽转矩分量,起到抑制齿槽转矩脉动的作用。仿真结果验证SVM-DTC比传统DTC的电流波形更平滑,磁链控制更精确。采用齿槽转矩补偿的方法后电机转矩脉动显著减小,验证了补偿控制算法的有效性。改进的控制算法提高了电机控制系统整体性能。 相似文献
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本文根据一款家用乘用车的结构和运行性能需求,设计出了额定功率95kW,峰值功率190kW的轴向磁通永磁电机。电机采用内单定子外双转子结构,定子铁心采用分块式设计形式。基于永磁电机设计理论,总结归纳轴向磁通永磁电机的初始设计流程,并对其电磁性能进行初始评估。采用有限元法建立电磁分析三维模型,对采用多种转子结构电机的电磁转矩、齿槽转矩、转矩脉动及永磁体涡流损耗等进行计算和分析。文中所归纳的电动汽车驱动用轴向磁通永磁电机设计流程及降低齿槽转矩、转矩脉动和永磁体涡流措施的效果对比,为此类电机的设计及优化提供借鉴经验。 相似文献
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磁通切换型永磁电机(简称磁通切换电机)是定子励磁型电机的一种,由于它在定子和转子上都开槽,因此,加载运行时尤其在低速时具有较大的转矩脉动和振动噪声。在这类电机中,由于交直轴电感几乎相等,因此其磁阻转矩平均值几乎为零,但是,会引起一定的转矩脉动。该文运用冻结磁导率方法,研究了磁通切换电机的磁阻转矩及其引起的转矩脉动产生机理;同时,该文也研究了磁阻转矩随电枢电流和定子绕组结构的变化规律。研究结果显示:在采用id=0控制时,磁阻转矩对输出转矩没有贡献,其平均值几乎为零,只会导致转矩脉动。此外,该文也分析了定、转子分别削角对磁阻转矩的影响规律。研究结果显示,采用转子直角削角和定子圆角削角相结合的方式可以使转矩脉动由25.3%降低到5.3%。 相似文献
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Marian Lukaniszyn Mariusz Jagiela Rafal Wrobel 《Electrical Engineering (Archiv fur Elektrotechnik)》2002,84(2):91-100
This paper presents a three-dimensional analysis of the magnetic field distribution for a three-phase, disc-type, permanent-magnet,
brushless DC motor with co-axial flux in the stator. Calculations are carried out using the 3-D finite element method (FEM).
The electromagnetic torque is determined from the Maxwell stress tensor. For comparison, various dimensions of permanent magnets,
pole shoes and air gap are analysed. It is shown that the ripple-cogging torque can be effectively reduced by an appropriate
permanent magnet width and air-gap length. The simulation results are in good agreement with experimental data obtained from
the prototype motor.
Received: 31 July 2001/Accepted: 18 September 2001 相似文献
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本文主要介绍了目前国内外潜油泵电力电缆主要的型号、规格及其生产工艺和使用的特点 ,并对各种类型的潜油泵电力电缆进行了对比性试验 ,供有关人员的参考。 相似文献
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Development of torque and flux ripple minimization algorithm for direct torque control of induction motor drive 总被引:2,自引:0,他引:2
M. Vasudevan R. Arumugam S. Paramasivam 《Electrical Engineering (Archiv fur Elektrotechnik)》2006,89(1):41-51
Direct torque control (DTC) is known to produce quick and robust response in AC drives. However, during steady state, notable
torque and flux ripple occur. They are reflected in speed estimation, speed response and also in increased noise. This paper
proposes a new control algorithm, which provides decoupled control of the torque, and flux with constant inverter switching
frequency and a minimum torque and flux ripple. Compared to the other DTC methods, this algorithm is much simpler and has
less mathematical operations, and can be implemented on most existing digital drive controllers. Algorithm is based on imposing
the flux vector spatial orientation and rotation speed, which defines the unique solution for reference stator voltage. This
paper contributes (a) Calculation of stator flux vector, torque and flux increments (b) The position of new stator flux vector
determination (c) Calculation of the stator reference voltage (d) comparison of errors of different control strategies. In
this paper, computer simulations and experimental results have been discussed for the proposed algorithm. 相似文献
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针对潜油电机在负载运行时,其细长的电机转轴发生许用扭转变形导致输出转矩下降、电流上升等问题,推导许用扭转角与电磁转矩削弱系数的解析表达式,建立细长转轴扭转角与电磁转矩下降的定量关系曲线,为潜油螺杆泵机组故障原因提供了理论依据。研制单元组合式永磁直驱潜油电机,对其细长转轴进行3D有限元扭转变形应力分析。基于转轴扭转变形结果建立电机2D和3D斜极等效有限元模型,进行机械应力场和电磁场耦合计算,得出电机电磁转矩的下降情况。研制样机进行单元电机组合运行试验,验证了转矩削弱系数表达式的正确性。 相似文献
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针对直接转矩控制技术以容差形式的Bang-Bang控制模式给系统的稳态运行带来的转矩脉动大、电流谐波成分重、定子磁链轨迹畸变等问题,将非奇异终端滑模控制应用到了转矩和磁链控制中.为了提高传统滑模控制的收敛性,分别独立设计了转矩控制器和磁链控制器的非奇异终端滑模平面.转矩控制器和磁链控制器由等效控制项和非线性切换项组成,非线性切换项中的符号函数sgn(S)通过积分作用削弱了控制量的抖振.仿真结果表明,非奇异终端滑模变结构直接转矩控制具有动态响应快、转矩波动和转速波动小、鲁棒性强、低"抖振"的特点. 相似文献
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Nakao Y. Naruse M. Suzuki Y. Itoh H. Sakai Y. Tagashira H. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1997,4(6):775-779
The propagation aspects of a creepage discharge in transformer oil are observed simultaneously and in detail under a positive impulse voltage condition, by means of a high-speed Schlieren optical system, an LED current measurement system and a charge measurement system using a capacitor. In the present paper, the influence of the material type and the thickness of insulating barriers on the propagation of the impulse creepage discharge are discussed for a point to plane electrode geometry. In addition, the influence of a barrier surface to the electric field direction on the propagation of the impulse creepage discharge is discussed for a parallel plane electrode gap with a protruding point 相似文献
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Zhou Yangzhong Hu Yuwen Huang Wenxin Zhong Tianyun 《Frontiers of Electrical and Electronic Engineering in China》2007,2(4):425-431
The electrically excited synchronous motor (ESM) has typically small synchronous inductance values and quite low transient
values because of the damper windings mounted on the rotor. Therefore, the torque and stator flux linkage ripples are high
in the direct torque control (DTC) drive of the ESM with a torque and flux linkage hysteresis controller (basic DTC). A DTC
scheme with space vector modulation (SVM) for the ESM was investigated in this paper. It is based on the compensation of the
stator flux linkage vector error using the space vector modulation in order to decrease the torque and flux linkage ripples
and produce fixed switching frequency under the principle that the torque is controlled by the torque angle in the ESM. Compared
with the basic DTC, the results of the simulation and experiment show that the torque and flux linkage ripples are reduced,
the maximum current value is decreased during the startup, and the current distortion is much smaller in the steady-state
under the SVM-DTC. The field-weakening control is incorporated with the SVM-DTC successfully.
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Translated from Proceedings of the Chinese Society for Electrical Engineering, 2006, 26(7): 152–157 [译自: 中国电机工程学报] 相似文献
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一种开关磁阻电机非线性磁链与转矩建模方法 总被引:2,自引:0,他引:2
开关磁阻电机(SRM)由于磁化曲线高度饱和非线性的特点,造成传统的电机性能分析和建模方法很难运用到SRM中。根据SRM磁链曲线的特点,提出了一种带修正因子的反正切函数来建立SRM模型的方法。在获得SRM 5个特殊转子位置处的9个磁链数据点的基础上,利用傅立叶级数分解和反正切函数来拟合SRM的磁链特性,并推导出电感和电磁转矩模型。该模型函数表达式简单、系数修改方便、计算精度高,并且能够直观的反映SRM的磁链、电感和转矩变化情况。以一台550 W、6/4极SRM为例,进行了仿真与实验比较,结果表明该模型能够很好的反映SRM的实际工作状况,验证了所建模型的精确性和有效性。 相似文献