Trend of permanent magnet synchronous machines

The performance of permanent magnet synchronous machines (PMSMs) has improved rapidly by the progress in elemental technologies such as electromagnetic material technology, computer‐aided design technology, control technique, and drive circuit technology, and thus PMSMs are attractive as high‐performance machines in various fields. This paper describes the recent technology and the trends in PMSMs. To begin with the PMSMs are classified by the ratio of magnet torque to the reluctance torque and their features described, then the trend of the motor design and the electromagnetic material for highly efficient PMSM is shown. The technologies that help to reduce the vibration and noise are also described, and the recently developed PMSMs for traction drive application are introduced. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Parameter measurements for permanent magnet synchronous machines

The advances in inverter drive technology and permanent magnet materials have enabled the application of permanent magnet synchronous machines (PMSMs) to various fields. PMSMs are rapidly spreading in their applications with their advantage of high efficiency, which is highly needed in many applications in recent years. Although there have been standardized measurement methods of the machine parameters for synchronous machines, they are not intended to apply to PMSMs. Therefore, several new measurement methods suitable for PMSMs have been proposed. This paper presents a review and analysis of these methods. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Recent technical trends in permanent magnet synchronous motors

This paper presents an overview of the recent technical trends in permanent magnet synchronous motors (PMSMs), especially the rare earth (RE)‐less PMSMs that have been developed in Japan. The RE‐less PMSMs, along with PMSMs with reduced RE permanent magnets (PMs), PM‐assisted synchronous reluctance motors (PMASynRM) with ferrite PMs, spoke‐type interior PMSMs (IPMSMs) with ferrite PMs, and axial‐gap PMSMs with ferrite PMs, are reviewed. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Trends of permanent‐magnet synchronous machine drives

This paper presents recent trends of permanent‐magnet synchronous motor (PMSM) drive technologies in Japan. Since the PMSM drives have many advantages over other drives, e.g. high efficiency, high power density, etc., many of the motor applications have been changing their power sources to the PMSMs. Particularly, interior permanent‐magnet synchronous motors (IPMSM) are epoch‐making and are intensively studied among researchers, scientists and engineers. According to the survey of the recent innovative technical trends, the PMSM drive technologies have been making a remarkable advancement in the fields of analysis‐and‐design techniques, various sensorless‐control techniques, power converter control techniques, and application specific drive systems. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Multiobjective optimum design method with anti‐demagnetization of high‐density permanent magnet synchronous motor

This paper presents a method of multiobjective optimization design with anti‐demagnetization aiming at the problem of irreversible demagnetization in high‐density permanent magnet synchronous motors (PMSMs) due to temperature and external magnetic field, at the same time considering the volume of permanent magnets and cost, torque ripple, and core loss. In the first step, a two‐dimensional magnetic network model is used to rapidly assess the basic design parameters and its ability to avenge the anti‐demagnetization of the PMSM. In the second step, the finite element method (FEM) is used to design the key parts of motor, and regression models that solve the model of the multiobjective problem are built based on the simulation experiment data. On this basis, multiobjective optimization result using genetic algorithm is used that can achieve a fast and efficiently global optimal solution. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Development trend of the permanent magnet synchronous motor for railway traction

Owing to the resent progress in power electronics and permanent magnet materials, a permanent magnet synchronous motor (PMSM) that is lighter, smaller, and more efficient than the conventional induction motor has become realistic as a traction motor. We are making research and development effort on the introduction of the PMSM to rail vehicle traction. The recent development trend of the permanent magnet synchronous traction motor is reviewed. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

基于奇异摄动的永磁同步电机无位置传感器控制

针对永磁同步电机伺服系统的双时间尺度特性,根据奇异摄动理论将永磁同步电机驱动系统的数学模型分解,得到快、慢两个电气子系统.基于快变电气子系统模型,采用Luenberger观测器构建快的位置估计器.通过慢变电气子系统构建慢的速度估计器.无位置传感器永磁同步电机闭环控制系统的计算机仿真结果表明,本文提出的算法既具有较高的辨识精度又具有相对少的计算量,速度跟踪性能可以满足永磁同步电机伺服系统无位置传感器控制需要.     

永磁同步电动机空载铁耗研究

从产生根源出发,对永磁同步电动机空载铁耗进行细致分类。在此基础上,利用有限元法和Bertotti铁耗计算模型,以一台5 k W、3 000 r/min永磁同步电机为例,对正弦波供电永磁同步电动机的空载铁耗分布特性进行分析计算,得到基本铁耗与空载杂散损耗的比例关系以及不同因素所引起的空载杂散损耗分布规律。进而,研究了变频器供电空载电流时间谐波引起的谐波损耗,分析了不同极槽配合对变频器供电永磁同步电机的谐波损耗影响规律。最后,通过多台样机的空载铁耗试验,验证了计算的正确性。     

双转子反向对转永磁同步电动机建模与仿真

双转子反向对转永磁同步电动机的两侧要形成反向对转的磁场,就要绕组三相反向排布。由于可以将它看成是两个永磁同步电动机反向串联,所以其电磁路的模型是两个永磁同步电动机模型的合成,但不是简单的合成。定子磁轭磁路为共用,会出现两侧同向和异向并联及串联形式;电路为共用电流形式;会导致该电机先天性的三相不对称,但可以通过优化设计使得三相不对称情况得到很好的解决。     

适用于电动汽车的PMSM宽转速最优PAM控制

脉宽调制电压型逆变器(PWM-VSI)主要用于变速永磁同步电机(PMSM)驱动中。然而,当PMSM端电压超出直流母线电压时将无法工作。这里提出一种优化的脉冲幅度调制(PAM)控制方法,利用Buck-Boost DC/DC变换器来调整逆变器直流母线电压。考虑到电动汽车上应用需求,该变换器还可实现功率的双向流动。在低速范围内,该系统能减小电压指令的总谐波失真,使电枢电流波形得到改善,转速范围得到扩展。为验证所提出的方法,最后给出了实验结果。     

A hybrid current controller for dual three‐phase permanent magnet synchronous motors

Control of the current harmonics is a critical issue for dual three‐phase (DTP) permanent magnet synchronous motors (PMSMs). Considering the limitations of conventional synchronous frame proportional‐integral (PI) current regulator, this paper presents a hybrid current controller that combines the PI current regulator with a multiresonant controller. With the proposed hybrid current controller, precise current control can be achieved with only a slight increase in the computational effort. Theoretical analysis and experimental results confirm the effectiveness of proposed current controller. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Refinement of inverter model considering dead‐time for performance improvement in predictive instantaneous current control

Model predictive instantaneous‐current control (MPIC), which was proposed in our earlier works, enables us to achieve better instantaneous current control using mathematical models of an inverter and permanent magnet synchronous motors (PMSMs). However, dead‐time to avoid short breakdown in the inverter is not usually considered in a general inverter model. Such an unmodeled part in the inverter model prevents accurate prediction of current evolution in motor systems based on the model predictive control. Therefore, in this paper, we analyze current response resulting from the dead‐time in the MPIC, and propose a refined inverter model considering the dead‐time so that control performance is improved. The effectiveness of the proposed method is verified through simulation and experiments. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

无速度传感器的永磁同步电动机滑模控制

采用反演控制理论构造了永磁同步电动机的速度观测器,并运用滑模变结构控制理论设计了系统控制策略.该方法利用了反演控制稳定性强,动、静态性能优良的特点,设计的观测器结构简单、精度高、稳定性好.使用滑模控制理论设计系统总体控制方法,可以有效抑制负载和参数变化带来的扰动,从而提高了系统的鲁棒性.文章对所提出的控制策略进行了理论分析,并且通过Matlab进行了仿真实验.仿真结果表明,该控制方法有效地实现了电机的转速跟踪,具有良好的动、静态特性和鲁棒性.     

Extension of Mathematical Models Taking Temperature Variation in Permanent Magnet Synchronous Motors into Consideration

We have developed novel mathematical models of d‐axis and q‐axis magnetic fluxes ?_d and ?_q for permanent magnet synchronous motors (PMSMs). The models can be used to approximate magnetic characteristics using simple fractional equations with i_d and i_q as variables. They include eight constants, and some of them represent the degree of magnetic saturation and cross‐coupling. However, the magnetic characteristics are varied with the temperature rise in PMSMs, which are dependent on the load torque and motor speed. In this paper, the characteristics of the eight constants that vary with the motor temperature and the residual flux density B_r are shown. Further, we propose to extend the mathematical models by considering the temperature and B_r variation.     

内置式永磁同步电动机转子结构的优化设计

为减小永磁同步电动机齿槽转矩和转动惯量,通过对永磁电机的齿槽转矩数学模型和空载轭部磁场进行分析,得出了通过采取辅助槽有效降低齿槽转矩,并在不影响其性能的前提下凿空转子铁心以减小转动惯量,然后以一台7.5 kW的内置式永磁同步电动机为例,采用上述方法对其转子结构进行了优化设计,最后通过Ansoft软件有限元分析验证了该方法是有效的。     

永磁体分散性对自起动永磁同步电动机的影响

由于批量生产的永磁材料在性能上存在不可避免的分散性,会造成永磁同步电动机性能的差异,采用理论分析与性能计算相结合的方法,研究了永磁材料性能的分散性对永磁同步电动机起动性能、空载性能和额定性能的影响,并以380V、22kW、6极永磁同步电动机为例进行了实验验证.结果表明:永磁体性能的分散性影响起动过程中的最小转矩,对电机的起动有较大影响;永磁体分散性对空载电流、空载功率因数、负载功率因数和过载能力影响较大,而对额定运行时的效率、电流影响不大.     

永磁同步电动机直接转矩控制系统研究

针对永磁同步电动机控制中存在低速时转矩脉动问题,对脉动问题形成的具体原因进行了探讨,详细介绍了永磁电机直接转矩控制理论,描述了常规永磁同步电动机直接转矩控制系统矢量选择方法和存在的不足,结合实际应用情况,提出了增加电压矢量的三电平逆变器控制方案,并给出了控制系统的结构图和数学模型。通过仿真分析,结果表明了该方案提高控制系统的性能,有效减小电机的电磁转矩脉动。     

绕组开路故障下的双三相永磁同步电机容错控制

针对汽车方向盘电动助力转向系统可靠性问题,基于双三相永磁同步电机(PMSM)研究了绕组开路故障下的容错控制策略。以一相绕组开路为例,通过推导出电机绕组开路时的坐标变换矩阵,建立了故障下的双三相PMSM d-q轴坐标系数学模型。在对电压方程进行解耦变换的基础上,设计了结合前馈补偿的电流调节器架构,研究了定子总铜耗最小的容错控制策略。仿真结果表明,所研究的控制策略改善了双三相PMSM绕组缺相后的运行性能。     

基于固定矢量作用时间的新型直接转矩控制系统

永磁同步电动机传统直接转矩控制具有转矩脉动大、开关频率不恒定等缺点,在分析传统直接转矩控制中磁链和转矩脉动的基础上,利用固定矢量作用时间合成新矢量的新型直接转矩控制方法控制永磁同步电动机.该方法根据转矩和磁链误差来选择基本电压矢量对,根据磁链的位置和转矩误差的大小来确定所选择的基本电压矢量的作用时间,从而得到了新的合成电压矢量进行控制.仿真结果表明基于固定矢量作用时间的新型直接转矩控制方法能够有效减小传统直接转矩控制方法中的磁链和转矩脉动,同时不增加控制的复杂性,明显改善了系统的控制性能.     

Reduction of Vibration in Concentrated Winding Permanent Magnet Synchronous Motor by Means of Skew Effects of Rotor

Global warming and the problem of successfully incorporating environmental safeguards are promoting the need for a more power‐efficient motor. Therefore, as a driving source, permanent magnet synchronous motors (PMSMs) with concentrated winding are widely used in a variety of fields. However, a PMSM with a concentrated winding generates more vibration than one with a distributed winding because of the radial electromagnetic force. This paper describes the effect of a new skewed rotor on the characteristics of a concentrated winding PMSM. We investigated this effect by three‐dimensional finite element method (3D FEM) analysis and measurement. We also demonstrate that the proposed rotor is effective in reducing the radial electromagnetic force without decreasing motor efficiency. © 2014 Wiley Periodicals, Inc. Electr Eng Jpn, 187(2): 33–43, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22400