扫描镜电机的电磁设计

为了设计以加速度最大化为目标的优化电机，分析扫描镜电机的结构特点，利用FEMM软件对扫描镜电机进行了电磁场计算与参数优化设计，根据磁场计算结果对扫描镜电机电磁参数与结构参数之间的相互关系进行分析，提出扫描镜电机设计的一般规律，通过实测数据验证了电机模型和电磁参数优化的正确性，并说明了电磁场计算模型的正确性。     

单绕组磁悬浮开关磁阻电机结构优化设计

针对单绕组磁悬浮开关磁阻电机结构参数的优化问题,提出了基于相关向量机与混合粒子群优化的方法。通过有限元分析计算了电机悬浮力和转矩与结构参数的关系,构建基于相关向量机非参数模型。以电机平均悬浮力和平均转矩最大输出为优化目标,采用混合粒子群优化算法获取最优结构参数,通过对比仿真实验说明了该算法的准确性与优越性,电机性能得到明显提升。     

新型建模及优化方法在BSRM中的应用

针对电机参数优化设计问题,引入多支持向量机与混沌优化算法,优化设计磁悬浮开关磁阻电机的结构参数。采用有限元仿真建立样本空间,采用多支持向量机构建磁悬浮开关磁阻电机的非参数模型,基于该模型,以满足额定电磁转矩为条件,优化电机参数,优化目标为最大的悬浮力、最小的转矩脉动、最小的绕组间互感,最优的电机结构参数通过混沌优化算法得到。仿真结果表明,BSRM利用多支持向量机所建立的非参数模型高效且准确,采用此优化方法设计的BSRM转矩脉动小、悬浮力大、绕组间互感小。     

高温超导直线感应电机的设计和电磁分析

本文介绍了高温超导直线感应电机的设计和电磁分析方法。首先,使用遗传算法得到一组优化的电机参数;然后,为了确定电机参数的准确性需要用有限元方法对得到的电机参数建模仿真;垂直穿过高温超导绕组的磁场(垂直磁场)对电机的临界电流影响很大,为了增加电机的临界电流,穿过电机初级超导绕组的垂直磁场应该尽可能地小。最后,要对建立的电机模型进行详细的电磁分析,以保证各项性能指标满足要求。     

用于简易变频器设计的新型扁平输入整流器

在制造横向磁场永磁电机（TFPM）电机之前，应确定最大转矩的波形。通过调整TEPM电机的各项几何参数，可以使电机达到其最大转矩。一种基于人工智能的最优化方法可以使得每个极间隔都获得理想的转矩波形。本文给出了一种用于优化TEPM几何参数的遗传算法，该算法同样适用于其它结构的电机。     

在几何结构设计中采用遗传算法优化横向磁场永磁电机的转矩波形

在制造横向磁场永磁电机（TFPM）电机之前，应确定最大转矩的波形。通过调整TFPM电机的各项几何参数，可以使电机达到其最大转矩。一种基于人工智能的最优化方法可以使得每个极间隔都获得理想的转矩波形。本文给出了一种用于优化TFPM几何参数的遗传算法，该算法同样适用于其它结构的电机。     

无刷直流电机RBF磁场定向控制及监控系统设计

针对现有无刷直流电机转矩脉动抑制方法存在抑制效果不理想,或脉动抑制效果好但学习算法复杂,不利于推广的问题,将RBF神经网络与磁场定向控制相结合,选用Luminary 615微控制器和无刷电机专用芯片MC33035,设计了无刷直流电机磁场定向控制系统。并开发基于Visual Basic的配套电机上位机监控系统,能在低成本下实现转速等参数的图形化显示及电机参数等的设置。实验结果表明,所设计的无刷直流电机RBF磁场定向控制系统转矩脉动小、控制精度高。     

基于散射中心的风电机叶片散射电场求解

为降低雷达系统的数据处理量及实现风电机实时目标特征识别,必须寻求风电机叶片散射电场的快速求解方法。针对传统电磁求解算法需处理巨量风电机叶片散射电场数据的问题,突破传统以超大电尺寸目标实体为基本单元进行广域空间电磁散射积分计算的思想,提出了一种基于散射中心的风电机叶片散射电场求解方法。基于非衰减指数和散射中心模型,通过距离-多普勒算法构建风电机叶片的雷达逆合成孔径图像,采用CLEAN 算法并结合相关系数提取风电机叶片的散射中心参数集,最终以散射中心产生的散射电场数据等效替代叶片本体的全部散射数据,实现了叶片散射电场的快速求解。以Vestas V82-1.65MW 型风电机为例,以矩量法计算结果为基准,文中所提方法计算准确度为93.20%,数据的压缩比达76.81,计算量的数量级比矩量法降低了106。     

8／6极开关磁阻电机两相励磁电磁转矩分析

为了准确掌握SR电机两相励磁状态下的电磁转矩情况,针对四相8／6极SR电机,采用准线性模型,从单相励磁运行时电磁转矩入手,将单相励磁转矩计算结果扩展至两相励磁运行状态。根据四相8／6极SR电机结构特点,在一个极矩下电磁转矩的变化过程中增加了两个过渡阶段,从而推导出两相励磁运行时电磁转矩的计算公式,绘制了单相与两相励磁转矩波形图,分析了两相励磁运行特点。最终从电磁转矩计算公式和转矩波形图上验证了两相励磁是SR电机提高转矩平稳性重要方法这一结论。     

基于粒子群算法的钻进参数多目标优化

为了使钻进过程达到最优,提出了基于机械钻速、钻头寿命和钻头比能的钻进参数多目标优化模型。参考典型的多目标优化进化算法NSGA-Ⅱ,提出了一种多目标粒子群算法(MOPSO)。采用一个钻进参数优化实例对优化模型和算法进行检验,得到分布均匀的Pareto最优解,一些最优解与传统的钻进参数单目标优化的解近似;讨论了算法中的种群规模、迭代次数和外部档案规模三个参数,得到一组兼顾解质量和计算时间的参数值,其计算时间的统计结果证明模型和算法满足钻进参数动态优化的要求。     

基于Ansoft汽车永磁电机磁场有限元分析

针对Ansoft Maxwell软件的电磁仿真方法是否有效,分别采用Ansoft Maxwell和Simplorer软件对磁场和电路进行仿真的方法。分析了永磁同步电机的结构,建立永磁同步电机的电-磁场理论模型和电磁损耗模型,用电磁仿真软件进行仿真。通过电机性能实验台测试永磁同步电机的关键输出特性,并与仿真结果进行对比分析。结果表明,参数误差均＜5%,验证了电磁仿真的有效性。     

用于空压机的高速电机的设计和分析

本文对一款130 kW,转速为31500 rpm用于空气压缩机的高速永磁电机进行了设计和分析。针对高速电机的设计指标,选择电机材料并采用磁路法计算出电机的各尺寸参数。利用有限元软件对所设计电机进行电磁场分析,同时分析电机的定转子损耗。然后通过分析电机护套材料和永磁体充磁方式,来达到减小电机内部损耗,降低温度,提高电机性能的目的。     

槽楔材料对PMLSM电磁特性的影响

为提高PMLSM的电磁性能并降低齿槽力和推力波动,文中提出一种在直线电机槽口安装槽楔的解决方案。槽楔材料对电机性能影响较大,为了使电磁性能最佳,文中以分数槽永磁直线同步电机为研究对象,分析了槽楔材料为硬磁、软磁和非磁时对电机气隙系数的影响。利用有限元法对比分析了3种槽楔材料下电机的气隙磁场、反电动势、齿槽力和推力波动等电磁性能,并对不同负载下削弱推力波动的程度进行对比。分析结果表明,硬磁性材料可以有效降低齿槽力和推力波动。最后研究了不同相对磁导率下硬磁性材料对电机性能的影响,并得到电机性能最佳时的相对磁导率值,为进一步提高电机性能提供了理论基础。     

Internal Permanent Magnet Motor Design for Electric Vehicle Drive

Power compaction and high efficiency are two key advantages of permanent magnet motors. This paper proposes an enhanced internal permanent magnet motor that delivers high torque, power compaction, and exceptionally high efficiency in the same operation area. The advantage of the proposed scheme is the magnetic flux accumulation in the air gap, which allows much higher values of magnetic flux density, compared to a surface permanent magnet motor of the same size. The original contribution of this paper resides on the adopted motor configuration, enabling to efficiently utilize the energy stored in the permanent magnet and to provide total loss minimization at the most frequently used speed range.     

Analytical and experimental investigation on the magnetic field and torque of a permanent magnet spherical actuator

This paper presents the torque model of a ball-joint-like three-degree-of-freedom (3-DOF) permanent magnet (PM) spherical actuator. This actuator features a ball-shaped rotor with multiple PM poles and a spherical stator with circumferential air-core coils. An analytical expression of the magnetic field of the rotor is obtained based on Laplace's equation. Based on this expression and properties of air-core stator coils, Lorentz force law is employed for the study of the relationship between the rotor torque and coil input currents. By using linear superposition, the expression of the actuator torque in terms of current input to the stator coils can be obtained in a matrix form. The linear expression of the actuator torque will facilitate real-time motion control of the actuator as a servo system. Experimental works are carried out to measure the actual magnetic field distribution of the PM rotor in three-dimensional (3-D) space as well as to measure the actual 3-D motor torque generated by the actuator coils. The measurement results were coincident with analytical study on the rotor magnetic field distribution and actuator torque expressions. The linearity and superposition of the actuator torque were also verified through the experiments.     

Three-phase modular permanent magnet brushless Machine for torque boosting on a downsized ICE vehicle

The paper describes a relatively new topology of 3-phase permanent magnet (PM) brushless machine, which offers a number of significant advantages over conventional PM brushless machines for automotive applications, such as electrical torque boosting at low engine speeds for vehicles equipped with downsized internal combustion engine (ICEs). The relative merits of feasible slot/pole number combinations for the proposed 3-phase modular PM brushless ac machine are discussed, and an analytical method for establishing the open-circuit and armature reaction magnetic field distributions when such a machine is equipped with a surface-mounted magnet rotor is presented. The results allow the prediction of the torque, the phase emf, and the self- and mutual winding inductances in closed forms, and provide a basis for comparative studies, design optimization and machine dynamic modeling. However, a more robust machine, in terms of improved containment of the magnets, results when the magnets are buried inside the rotor, which, since it introduces a reluctance torque, also serves to reduce the back-emf, the iron loss and the inverter voltage rating. The performance of a modular PM brushless machine equipped with an interior magnet rotor is demonstrated by measurements on a 22-pole/24-slot prototype torque boosting machine.     

Analysis of direct torque control in permanent magnet synchronousmotor drives

This paper describes an investigation of direct torque control (DTC) for permanent magnet synchronous motor (PMSM) drives. It is mathematically proven that the increase of electromagnetic torque in a permanent magnet motor is proportional to the increase of the angle between the stator and rotor flux linkages, and, therefore, the fast torque response can be obtained by adjusting the rotating speed of the stator flux linkage as fast as possible. It is also shown that the zero voltage vectors should not be used, and stator flux linkage should be kept moving with respect to the rotor flux linkage all the time. The implementation of DTC in the permanent magnet motor is discussed, and it is found that for DTC using available digital signal processors (DSPs), it is advantageous to have a motor with a high ratio of the rated stator flux linkage to stator voltage. The simulation results verify the proposed control and also show that the torque response under DTC is much faster than the one under current control     

A direct torque control algorithm for permanent magnet synchronous motors with minimum torque pulsation and reduced electromagnetic interference noise

In this work, a sensorless hysteresis direct torque control (HDTC) algorithm for a permanent magnet synchronous motor is described. The algorithm uses the output of two hysteresis controllers used in the traditional HDTC to determine two adjacent switching vectors per one sample time. The algorithm also uses the magnitude of the torque error, magnitude of the flux error and stator flux position to select the switching time for the selected vectors. The selection of the switching time utilises table structure which reduces the complexity of calculation. The simulation results of this proposed algorithm show adequate dynamic torque performance and considerable torque ripples reduction as well as lower current ripples and reduced electromagnetic interference noise level, as compared with HDTC.     

基于滑模控制的永磁同步电机直接转矩控制研究

针对永磁同步电机直接转矩控制(DTC)存在较大的电磁转矩脉动、磁链脉动、低速性能不理想等问题,文中引入滑模控制策略对永磁同步电机进行直接转矩控制。通过建立PMSM的矢量数学模型,设计基于滑模控制的直接转矩控制器,利用MATLAB/Simulink进行建模仿真分析。结果表明,与传统DTC相比,基于滑模控制策略的永磁同步电机直接转矩控制系统中电磁转矩脉动幅值更低,且具有更好的动态性能和抗扰动能力,可以更加有效地改善系统特性,满足实际电机控制的需要。     

永磁同步电机直接转矩控制系统的仿真研究

文章分析了永磁同步电机直接转矩控制的原理,阐述传统直接转矩控制系统转矩脉动的缺点,本文将空间矢量脉宽调制技术引入永磁同步电机的直接转矩控制系统中,利用空间矢量的调制过程,可在相同的系统硬件条件下得到更多的、连续的电压空间矢量,进而得到对电机更准确的控制。仿真结果表明,该方案既保持了直接转矩控制快速动态响应,又减小了电机转矩的脉动。