直流马达控制及其在短波发射机调谐系统中的应用

本文简要论述了直流马达的工作原理及开关驱动技术,并分析和对比了Thales公司250（II）型发射机和大陆公司418E型发射机马达驱动和控制的工作原理。通过这种对比阐述了数字技术对马达控制技术发展的重要意义。     

降低直接驱动式电唱盘马达振动的一种新方法

当直接驱动式马达旋转时,转盘与底座、马达的转子与定子之间会产生作用力与反作用力,这样就会导致音臂的振动,从而影响了声重放质量。本文介绍的方法是增加辅助马达或转矩发生器从而将这些力减至最小;将主驱动马达和辅助马达或转矩发生器进行反相驱动,这样便可大大地减小旋转平面内底座的振动。这项技术从本质上改善了音质。     

微纳米马达聚集的驱动方式以及应用研究现状

简单阐述了微纳米马达及相关领域的发展历程,详细介绍了在微纳米马达驱动技术的基础上调控微纳米马达发生聚集,重点阐述了通过化学驱动和物理驱动等一系列驱动方式使微纳米马达之间相互发生作用、产生运动并在可控的情况下表现出的聚集行为。从聚集现象能有效提升微纳米马达执行任务的效率、增强完成复杂任务能力的角度出发,归纳了通过化学能、声能、磁能、电能、光能来驱动微纳米马达进而实现聚集的研究成果,总结了近年来微纳米马达在聚集领域的研究进展,以及在生物医学中对相关疾病治疗的成功应用。最后,对微纳米马达聚集现象的未来发展方向与面临的挑战进行了展望。     

液体媒质非接触型压电超声马达机理研究

介绍了一种液体媒质非接触型压电超声马达;这种马达的定子与转子是不接触的,且转子处于液体媒质中,定子压电振动所产生的能量通过定、转子间的液体传递给转子,从而驱动转子旋转,是压电超声马达的一个新的研究领域,文章给出了液体媒质非接触型压电超声马达的结构及驱动电路,对其运行机理进行了分析,并对目前存在的问题及进一步的研究方向作了阐述。     

直线超声马达研究进展

简述了近十年来直线超声马达的研究进展,分析了超声马达在结构设计和摩擦驱动等方面的关键问题。分析表明,开发新型原理的超声马达方兴未艾,但接触型马达为目前直线马达的主要发展方向。本体结构简化、驱动性能增强、工作效率及稳定性提高,是超声马达结构设计时应考虑的目标和任务。但接触型直线马达正常工作过程就是定/动子间的高频冲击磨损过程,定动子间摩擦学设计至关重要。另外,装配预紧力、接触间隙和磨损过程等引起的非线性问题,在马达设计制造和使用维护中应给予关注。最后,探讨了马达使用性能及运行寿命的影响因素,并总结了直线超声马达工作过程中的能量损失缘由和噪声产生机理。     

环形行波超声马达驱动电路的研究和设计

在介绍超声马达运行机理的基础上，分析了环形行波超声马达对驱动电路的要求，用驱动电路解决了超声马达中压电振子的极化问题，设计出了一种新颖的具有频率自动跟踪功能的行波超声马达驱动电路，分析了驱动电路的工作条件，得到了超声马达转速频率关系曲线。     

自动化技术与远动技术

0605030 非接触压电马达驱动机理分析[刊,中]／刘景全／／压电与声光．-2005,27(5)．-562-565(L) 主要研究行波型非接触压电马达的驱动机理,该文引入边界层概念,对振动体产生的边界层进行分析, 探讨行波型超声波非接触驱动机理。给出在振子产生     

复合型超声马达驱动转矩的分析

以复合型超声马达为研究对象,分析了在不同情况下的最大输出转矩,通过实验研究了超声振动产生的悬浮力对极限输出转矩振动应满足的条件,为准确设计复合型超声马达提供了依据。     

遗漏脉冲检测器保护变压器

作为天体望远镜控制器的一部分, 本电路向驱动马达提供一个AC 驱动波形。AC输出频率由一个外部振荡器设备调节,以产生所希望的 驱动速率。     

利用Fluke 87V数字多用表测量调速马达

在过去，马达的维修一般是指处理传统的三相马达故障，这些故障主要是由进水、灰尘、油脂、轴承损坏、马达轴心偏离，或者仅仅是由正常老化造成的。但是，随着电子马达的使用，马达的维修已经发生了很大变化，更多的是对调速马达驱动(ASD)进行维修。这些驱动有许多特殊的测量问题，就连经验丰富的专家也会对此感到头疼。     

开关磁阻电机基于转矩脉动最小化的直接转矩控制技术

开关磁阻电机的主要缺点是转矩脉动较大以及振动和噪声比其他调速系统严重。这里将直接转矩控制技术应用到开关磁阻电机中,以转矩脉动最小化为主要控制目标,在此基础上建立了直接转矩控制的仿真模型。仿真及实验研究表明,直接转矩控制技术能够将磁链矢量幅值很好地控制在滞环带内,从而有效地控制转矩脉动,降低电机的振动和噪声。     

异步电机直接转矩弱磁控制研究

针对异步电机直接转矩控制系统的弱磁控制,提出了一种新的弱磁控制策略。该策略最基本的思想就是使磁链给定值跟随着转矩误差的变化。该算法不需要复杂的电机参数而且能够实现各个速度段的平滑过度。在整个运转过程中限制定子磁链不超过设定值,在不同的速度区段给定不同的定子磁链,易于实现。最后,文章通过仿真验证了该控制策略可实现异步电机直接转矩控制系统的弱磁升速和减速过程。     

Speed and Load Torque Observer Application in High-Speed Train Electric Drive

This paper presents an application of induction motor mechanical speed and load torque observers in high-speed train drives. The observers are applied for a 1.2-MW electric drive with an induction motor. The goal of using such observers is to utilize computed variables for diagnostic purposes of speed sensors and torque transmission system. The concept of diagnostic system is presented in this paper, and proper criteria are proposed. The suggested system is designed to work without a speed sensor in the case of existing sensor faults. Monitored motor load torque is used to limit the maximum motor torque in the case of existing problems in the gearbox. The results of simulation and experimental investigations for a 1.2-MW induction motor drive are presented.      

Design and control of a permanent magnet spherical wheel motor

We present a permanent magnet–based spherical wheel motor that can be used in omnidirectional mobility applications. The proposed motor consists of a ball‐shaped rotor with a magnetic dipole and a hemispherical shell with circumferential air‐core coils attached to the outer surface acting as a stator. Based on the rotational symmetry of the rotor poles and stator coils, we are able to model the rotor poles and stator coils as dipoles. A simple physical model constructed based on a torque model enables fast numerical simulations of motor dynamics. Based on these numerical simulations, we test various control schemes that enable constant‐speed rotation along arbitrary axes with small rotational attitude error. Torque analysis reveals that the back electromotive force induced in the coils can be used to construct a control scheme that achieves the desired results. Numerical simulations of trajectories confirm that even without explicit methods for correcting the rotational attitude error, it is possible to drive the motor with a low attitude error (<5°) using the proposed control scheme.     

Analysis of Performance of Adjustable-Speed Drives during Voltage Sags

The induction motors are the most common electric machines on industrial systems and with extended applications when adjustable speed drives (ASD) are used. The speed drives are based on power electronic devices and therefore they are highly sensitive to electric disturbances such as voltage sags, interruption, etc. Voltage sags has become one of most common power quality problems in the electrical systems, producing negative effects mainly in loads with power electronic technology. In this paper, the analysis of the effects produced by voltage sags in the ASD and the induction motor are presented. The electric system used for the analysis is conformed by an induction motor, an AC drive with V/Hz control scheme and a step down transformer connected in Yd. The voltage sags were produced by faults in the electric system with a time duration of 6 cycles (0.1 s). The whole electric system was modeled and simulated in Matlab/Simulink environment. The operating conditions of the induction motor was 80% of nominal speed and full load. The obtained results show high sensitivity of the drive, mainly to the dc-link voltage drop, resulting in a motor speed drop and overcurrents in the drive feeders at the ending sag. The adopted parameters used as a limit for the speed drive disruption were 5% of variation in the motor speed and 1.5 p.u. for the peak current. The most severe effects occur with sags type A and G due to three-phase and two-phase to ground faults respectively. The effect of these sags produced a dc-link voltage drop higher than 30% and therefore the drive disruption as a result of the operating limits exceeded. With voltage sags type C and D, caused by single-phase to ground and two-phase faults respectively, the effects produced in the drive and the motor are negligible.     

交流电机高性能转矩控制教学内容设计

交流电机高性能转矩控制是交流调速课程讲授的核心,也是学生学习的难点。本文从交流电机产生转矩的物理本质出发,结合转矩和磁链解耦控制特征,全面阐述了交流电机中高性能转矩控制数学模型;基于这些模型分析了当前两种典型的交流电动机高性能转矩控制系统结构,最后给出实验结果。课堂教学结果显示,本文提出的教学内容设计能够使得学生迅速抓住交流电机高性能转矩控制本质,取得了很好的教学效果。     

Quasi-Z源逆变器PMSM系统直流环节电压控制方法

可变直流环节电压控制能够提高电动机驱动系统的运行效率。目前,Z源逆变器电机系统直流环节电压参考值由电机电流和转速计算得到,但电机电流变化时,电压参考值会产生非必要波动,影响电机稳定运行。为降低参考电压波动对系统的影响,该文提出了一种直流环节参考电压线性计算方法。该文介绍了直流环节电压控制原理,并说明了推导方法。与一般方法相比,线性控制方法摆脱了电流波动对直流环节电压的影响。最后,通过仿真验证了该方法的可行性和有效性。     

An induction motor drive using an improved high frequency resonantDC link invertor

An induction motor drive that uses an improved high-frequency resonant DC link inverter is presented. The resonant circuit was systematically analyzed first to establish the criteria for initial current selection, and a circuit to establish the bidirectional initial current was then proposed. The proposed current initialization scheme solves voltage overshoot and zero crossing failure problems in the ordinary resonant DC link inverters. A three-phase 3 kW insulated-gate-bipolar-transistor (IGBT) based 60 kHz resonant link inverter has been constructed and successfully tested with an induction motor drive. The speed control system is implemented using two microprocessors. Experimental results are presented to show superior operation of the proposed resonant DC link inverter drive     

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。     

基于Matlab GUI的电机拖动辅助教学平台设计

交、直流电动机起动、调速、制动方法分析是《电机与拖动》课程教学中的重点问题,控制方式种类多,课堂教学主要是运用公式推导的理论分析方法,过程复杂且抽象难懂。利用Simulink建立交、直流电机拖动系统电气结构图仿真模型,GUI建立操作界面,二者交互链接开发电机拖动辅助教学平台,并以直流电机直接起动和电枢串电阻起动模块为例对设计过程中的关键技术进行了详细说明。该平台可实现原理说明、模型运行、参数设置、波形显示、结果分析等功能,对电机拖动原理以及效果的深入理解有很好的辅助作用。