Analysis of Torque Ripple of Permanent Magnet Brushless DC Motor

Torque tripple has significant effect on performance of permanent magnet brushless DC motor. This paper presents a mathematical model built for such a motor, the analysis of torque tripple for a brushless DC motor with sinusoidal flux distribution, which is verified by torque tripple experiments run with a test motor, and equations developed for torque tripple resulting from different sator current errors.

Design and Optimization of Line-Start Rare-Earth Permanent Magnetic Synchronous Motor Basing on FEM

The 2D transient FEM was used to analyze the starting process of the three phase rare-earth LS-PMSM.By verifying the simulation result with the experiment one, we get the conclusion that it is consistent with the experiment result very well.At the same time, by analyzing the situation of the magnetic bridge, we also get the result that the amplitude of EMF waves are changing with the situation of the magnetic poles and we can optimize the motor's structure at the same time.

Temperature Research of Permanent Magnet Brushless DC Motor for Electric Balanced Vehicle

A power system structure composed of a brushless DC motor and a cycloidal reducer for electric balanced vehicle has been proposed, and the temperature of important components in this structure would be discussed. The loss generated by the cycloid reducer is negligible, it’s only need to analyze the thermal field of motor. Since the temperature change will affect the material properties of the target motor, the electromagnetic and temperature fields, involved in the motor, are selected for coupling calculation to determine whether the final temperature distribution can meet the requirements of vehicle for use.

Simplified EKF Based Sensorless Direct Torque Control of Permanent Magnet Brushless AC Drives

A simplified extended Kalman filter (EKF) based sensorless direct torque control technique for a permanent magnet brushless AC drive is proposed. Its performance is compared with that obtained with other sensorless methods for estimating the rotor speed and position from a stator flux-linkage. Since the EKF has an inherently adaptive filtering capability and does not introduce phase delay, the technique provides better speed estimates. In addition, the technique is easy to implement and requires minimal computation.

Design optimization of a slotless PM brushless motor with helical edge wound laminations for rim driven thrusters

This paper discusses the analysis and design of a very thin slotless permanent magnet （PM） brushless motor whose stator laminations are manufactured from a single strip of steel that is edge wound into a spiral （like a ＂Slinky＂） and then fitted over the windings that are preformed on the outside surface of a non-conducting former. Analytical and finite element analysis （FEA） are used to determine the con- strained optimum dimensions of a motor used to drive a rim driven thruster in which the motor rotor is fit- ted onto the rim of the propeller and the stator is encapsulated in the thin Kort nozzle of the thruster. The paper describes the fabrication of a demonstrator motor and presents experimental results to validate the theoretical calculations. Experimental motor performance results are also reported and compared with those of a slotted motor that fits within the same active radial dimensions as the slotless motor. The slotless motor, which has longer active length and endwindings, and thicker magnets than the slotted motor, was found to be less efficient and more expensive （prototype cost） than the slotted machine.

Six-step Voltage Control of PM Brushless AC Motors under High Speed Flux-weakening Operation for EV/HEV Applications

The torque-speed characteristics of brushless motor having an interior permanent magnet rotor and a sinusoidal back-emf waveform are compared experimentally when it is operated in brushless AC(BLAC) mode and brushless DC (BLDC) modes with both 2-phase,120° conduction(BLDC-120) and 3-phase,180° conduction(BLDC-180).Particular emphasis is on high-speed,six-step voltage controlled,flux-weakening operation.It is shown that for EV/HEV applications,even for interior PM brushless motors which have sinusoidal back-emf waveforms,in order to achieve maximum torque per ampere capability over wide operation speed range,it is advantageous to employ a hybrid operation mode-BLAC operation in the constant torque region and six-step voltage control(BLDC-180 operation,together with current phase control) in the flux-weakening region.

车用永磁无刷直流电机弱磁控制仿真研究

永磁无刷直流电动机的转矩与转速会对电机的控制精度造成影响,导致电机弱磁控制效果差。为了提升整体控制性能,提出车用永磁无刷直流电机弱磁控制仿真方法。分析车用永磁无刷直流电机弱磁转矩特性,获取电机电磁转矩关系。根据获取结果建立永磁无刷直流电机弱磁控制系统,利用该系统控制电机弱磁的电磁转矩与运行效率,以此实现整体控制。实验结果表明,通过对所提方法开展电机运行效率测试、电机运行稳定性测试,验证了上述方法的有效性。

微型永磁无刷直流电机的设计与优化

对一款航空用微型永磁无刷直流电机进行了设计,永磁体选用钐钴进行Halbach阵列充磁,并对电机的部分参数进行了优化,与原方案相比,优化了电机的输出转矩。制作了一款实物样机,通过对样机的测试,验证了优化的可行性。

永磁无刷直流电机定子齿部辅助槽对转矩特性的影响分析

推导了齿槽转矩表达式并分析了电机槽极配合对齿槽转矩和转矩波动的影响。基于一款6槽8极的永磁无刷直流电机,研究定子齿顶开槽对齿槽转矩的抑制作用。有限元仿真分析表明,电机齿槽转矩和转矩特性与辅助槽数量和槽口尺寸有较大关系,当定子齿顶开2个辅助槽、槽深0.6 mm槽宽2.0 mm时,齿槽转矩下降了69.1%。样机实测数据验证了有限元分析的结果。

Improved Sensorless Operation of Interior PM BLAC Motor Drives with Reduced-Order EKF

It is a challenge to realise an EKF-based sensorless controller for an Interior Permanent Magnet （IPM） brushless ac motor drive due to the influence of nomlinearities and rotor saliency. An improved reduced-order EKF method is presented, reducing the rotor position estimation error of an IPM motor, as evident in [1] due to the neglect of saliency. The effectiveness of the proposed method is verified experimentally.

电子水泵永磁无刷直流电机性能影响因素的仿真分析

为了满足新能源汽车电子水泵研发过程中对永磁无刷直流电机性能的设计要求,需要对该类电机的性能的影响因素进行分析。首先以电机行业一般设计标准和其它电机产品的设计经验作为依据,得出电机设计必需的物理量。然后基于ANSYS Electronics Desktop中的RMxprt软件进行参数化设计计算,初步得到一个性能参数较为合理的电机模型。最终,通过数值模拟得出设计工况下铁芯长度、永磁体厚度、极数和气隙四种关键设计变量与电机转速、转矩、效率等性能的定性关系。这些参数的变化趋势可以指导电机研发人员按实际需求定制电机的性能。

单相无刷直流圆筒直线电动机及其起动推力研究

提出了一种单相无刷直流圆筒型直线电动机(SPBLDC-TLM),利用有限元方法对其电磁性能进行了分析。与三相无刷直流圆筒型直线电机对比,SPBLDC-TLM具有推力峰值大、结构简单以及成本低等优点。针对SPBLDC-TLM起动推力为零的问题,提出了斜齿和高低齿两种非对称齿结构,对比分析了两种齿结构不对称度对起动推力以及推力峰值的影响规律,为SPBLDC-TLM的起动性能优化提供了参考。结果表明,斜齿结构不对称度对起动推力影响较小,而高低齿不对称度的增大可以显著增加起动推力。采用有限元法和MATLAB软件,验证了两种非对称齿结构的有效性。

线控转向电机自抗扰伺服控制系统研究

选择永磁同步电机作为转向电机,研究基于自抗扰控制器的电机伺服控制技术。首先,对永磁同步电机在旋转交直轴坐标系下的数学模型进行介绍,选择转子磁场定向矢量控制策略。其次,将电机位置、速度环整合,设计了一个二阶自抗扰控制器,减少电机内外扰动的影响,抗干扰能力较PID控制器有较大提升。针对二阶自抗扰控制参数众多、调节困难的问题,利用模糊算法对自抗扰控制器的非线性状态反馈控制器参数进行优化,设计了永磁同步电机伺服控制系统位置速度模糊自抗扰控制器。最后,在Simulink中搭建电机控制模型并进行仿真分析,验证本文中控制策略以及算法优越性。

低速大扭矩永磁无刷直流电机矢量控制技术研究

面对传统农机动力源向电力转变的趋势,结合传统高速永磁无刷直流电机的控制策略,针对低速大扭矩永磁无刷直流电机的特点,本文在转速、电流双闭环的基础上采用矢量控制技术,通过仿真实验,与直接转矩控制在低速大扭矩永磁无刷直流电机的控制方面的性能进行对比,证明该策略对于低速大扭矩永磁无刷直流电机的控制能起到较好的效果,对于低速大扭矩永磁无刷直流电机的控制研究有一定的参考价值。

永磁同步伺服电动机研究

针对人们对伺服电动机在概念认知上的模糊与混乱现象,文章从控制工程角度给出关于伺服电动机的一个统一定义。另外,就三相永磁同步伺服电动机与直流无刷电动机的关系与区别进行了剖析,将这两种伺服电动机统一到永磁同步伺服电动机这个类属之中。

定子无铁心永磁无刷直流电机驱动拓扑设计方案及对比

单级三相全桥驱动拓扑无法保证力矩控制模式的定子无铁心永磁无刷直流电机在全电流指令范围内电枢电流连续。采用增加电枢回路等效电气时间常数的思路,选取Buck+半桥、全桥串联电感、Buck+全桥三种驱动拓扑,对三种驱动拓扑保证电机正常运行的条件以及不同驱动拓扑的固有属性进行理论分析、说明和对比。在基于数字控制器的三种驱动平台上,使用同一台电机进行实验验证。实验结果表明,三种驱动拓扑均能保证电机的正常运行,实测电流波形证明了关于拓扑特点的理论分析的合理性。对三种驱动拓扑实测稳态运行性能进行了详细的数学分析,为小功率无铁心永磁无刷直流电机的工程应用提供了参考依据。

高速永磁无刷直流电机损耗优化设计研究

为提高便携式电动检修工具的续航能力并减少其发热,需要降低电动工具驱动用高速永磁无刷直流电机的损耗。本文提出一种通过结合定子裂比和铁心磁通密度优化实现损耗最小的BLDCM设计方法。构建了BLDCM的电磁模型,推导出铜耗、铁耗等损耗与定子裂比及铁心磁通密度的解析关系,求解使总损耗最小化的定子裂比与铁心磁通密度最佳组合。以一台20000 r/min的高速无刷直流电机为例,通过有限元仿真和实验测试对所提优化方法的准确性进行了验证。仿真和试验结果表明,所提BLDCM优化设计方法可以有效获取最优定子裂比和磁场强度,进而确定电机最优方案,使电机损耗最小。

永磁无刷直流电机在高速电动手术工具中的选型与优化设计综述

随着高速电动手术工具使用量的日益增加,关于其核心部件——驱动电机的研究越来越广泛。永磁无刷直流电机因具有小巧高效、稳定可靠等特点,在该应用领域备受关注。该文介绍了永磁无刷直流电机的组成及优势,结合高速电动手术工具的临床应用需求,对永磁无刷直流电机本体、位置检测电路和换相控制电路的选型与优化设计方案进行了论述和比较,并指出了相应的关键技术难点与解决思路。最后对未来研究重点进行了总结与展望,为永磁无刷直流电机在高速电动手术工具中的设计研发提供理论参考。

高速电动手术工具驱动电机设计及优化研究

为提高高速电动手术工具的转速和稳定性,本研究设计了一款转速为70000 rpm的永磁无刷直流电机。首先,对电机本体、位置检测电路和换相控制电路的主要组成部分进行结构选型,并计算各项电磁参数;其次,在Ansys Maxwell电磁仿真软件中绘制电机模型,进行稳态与瞬态有限元仿真,验证其性能;最后,采用响应曲面法,建立以定子内径、转子外径、永磁体厚度为优化变量,空载电流为优化目标的优化方程,并分析求解。结果表明,优化设计后的永磁无刷直流电机,空载电流降低了57.8%,有效提升了高速电动手术工具应用的可靠性。

基于ARM+FPGA的永磁无刷直流电机控制智能方法

永磁无刷直流电机具有效率高、易维护等特点,目前广泛应用于电动汽车、航空、船舶等行业。由于该种电机存在着转矩波动大等不足,为提升其控制性能,从控制平台改进与控制算法优化两个方向开展研究。首先,研究并设计了基于ARM+FPGA的电机控制硬件平台,使用AXI高速数据交互协议,解决了传统电机控制平台中延时较大、算法能力有限的问题;然后,使用基于径向基神经网络的磁场定向控制智能算法实现了对电机的精确控制;最后,通过仿真和实验与磁场定向控制方案进行了对比,结果表明:采用基于ARM+FPGA的永磁无刷直流电机控制智能方法,其调节时间平均缩短了3.22 ms,超调量平均降低了4.35%,提高了BLDC控制精度和运行性能。