浅析高压电动机振动值与电能质量之间的联系

为探讨高压电动机在运行时出现的电机本体振动值偏高问题的原因,将电能质量技术应用到电动机振动分析中.通过理论简析和实测数据建立了电流不平衡性与电机振动值之间的关系,提出电动机进线电流不平衡是迫使其振动值偏大的重要原因.实测数据分析结果表明,外电源进线电压不平衡是引起电机振动值偏大的直接原因之一.     

转子静偏心状态下机床电主轴电磁力有限元分析

电磁振动是电磁直驱型机床电主轴不可回避的振动来源,为了抑制电磁振动需要探讨其电磁力的频谱特征。推导了三相异步电主轴的电磁力波计算公式,重点分析了转子偏心状态下的电磁力波特点。基于Ansoft电磁场计算软件,建立了某国产电主轴的电磁场有限元分析模型,获得了电主轴的运行特性曲线。研究了转子在不偏心和偏心状态下的电磁力频谱变化规律,结果表明,静偏心会使电磁力力波成分更为丰富; 偏心的增加不会影响电磁力的阶次和频率分布,但与不平衡磁拉力的幅值和低阶力波幅值成正相关关系,将加剧电主轴的振动。     

基于异步电动机的电动汽车驱动系统

为了顺应汽车低碳环保的发展趋势,将异步电机用作电动汽车的驱动电机来代替价格昂贵且环保性差的永磁同步电机。采取转子磁链定向矢量控制的方法来实现异步电机的调速控制,在此基础上建立了一个异步电机作为驱动电机,由电池和双向DC/DC供电的电动汽车驱动系统。推导了异步电机的数学模型,搭建了一个小型电动汽车实验平台,并在实验平台上对异步电机调速性能和双向DC/DC供电系统进行了实验验证。实验结果表明,采用转子磁链定向矢量控制能很好的实现电动汽车的驱动系统的调速控制。     

船用异步电动机电磁振动有限元分析

针对船用YH系列异步电动机电磁振动问题,在分析了电动机电磁振动的源头是径向电磁力波的基础上,介绍了有限元计算径向电磁力波的基本原理,利用有限元仿真分析软件对比分析了不同槽配合、不同转子槽形、不同气隙长度的径向电磁力波各次谐波幅值,从而找出了各个电磁参数与船用异步电动机电磁振动的关系,首次提出了低振动低噪声交流异步电动机电机电磁设计准则。     

基于VB的岸桥机房电机底座振动快速分析

根据岸桥机房振动测试结果分析出导致机房振动的主要原因,发现提高电机底座横向刚度可以有效抑制振动.基于将系统简化为单自由度强迫振动模型和有限单元法两种计算方法,利用VB分别编制了能将电机及底座参数化的振动快速分析软件.通过分析电机底座不同结构布置形式对其固有频率和最大振动响应速度的影响可知,增大电机底座截面惯性矩可以降低系统振动响应;快速分析软件分析结果与ANSYS计算结果一致,同时比较了用两种方法编制的软件的优缺点.运用所编软件对某岸桥机房电机底座进行了快速优化设计,振动实测数据与分析结果吻合,证明了快速分析软件分析结果的可信度和所用方法的可靠性.     

On some opportunities for improving vibration machines with self-synchronizing inert vibration exciters

Two opportunities for improving vibration machines with self-synchronizing unbalanced (inert) vibration exciters with an above-resonance operating vibration frequency are considered. The first opportunity regards machine startup modes, and the second concerns operation in the established mode. The proposed improvements allow one to decrease generating motor power, power consumption, and the operational dynamic load.     

齿谐波磁场的分析研究及计算机仿真处理

研究分析了磁场对电机运行性能的影响一直是电机电磁设计中的一个重要课题。该齿谐波电机齿槽的电磁设计，通过对3．8kW的小型异步电动机齿槽电磁设计和运行性能的计算机程序仿真，取得了良好的效果。基本达到消除高次谐波、齿谐波，改善异步电动机的运行性能的目的。     

三角位移转换式压电直线电机

为了在保持电机精度的同时获得较大作动行程,提出了一种以叠层压电陶瓷作为激励振动源的压电直线电机。分析了电机的工作原理,推导了电机驱动足在工作时的运动轨迹。设计安装了电机样机,并对其定子进行了测试。最后,在两种激发条件下实验研究了电机的整机性能。结果表明:单组叠层压电陶瓷激励时,该样机定子驱动头在接触面法向和切向同时具有振动分量,并能够在阶跃和连续两种不同激励方式下实现单向大行程直线运动。以锯齿波激励时可实现步进运动,激励频率为20Hz时步距为0.1μm;以两路相位差π/2的正弦波激励时,可在1.5kHz到5.8kHz的激励频率区间输出稳定连续的直线运动,其运动速度随激励频率的升高而增大,在峰-峰值110V(50V偏置)的正弦电压激励下其推力可达4.8N。该电机具有高位置分辨率和宽频率响应,可以在两种工作模式下分别稳定地实现直线步进和大行程连续运行。     

Bi-modes alternation stepping ultrasonic motors

Based on the principle of alternative operation of two bending vibration modes in an annular stator, this paper presents a standing-wave stepping ultrasonic motor characterized by no accumulative errors driven by an open-loop control circuitry. The driving forces are generated from the motions of projections on the stator in two modes. The positioning of the motor is achieved by the cooperation between the stator projections and rotor teeth, and the number of the rotors determines the stepping angle of the motor. Two-phase sinusoidal signals corresponding to the two modal frequencies drive the motor bi-direction stepping rotation via a switch unit. The prototype runs steadily without miss-step on trial. The single-step angle displacement of the motor is 2.5°.     

浅谈利用三相异步电机发电的原理和意义

根据三相异步电动机的运行状态,对电动机改做发电机运行的过程进行了深入分析和研究,提出了异步电动机作发电机运行时需要注意的事项,并通过了实验室的试运行。     

燃料电池轿车动力总成悬置系统的优化设计

以某燃料电池车为研究对象,建立了电机动力总成悬置系统的动力学模型,通过分析动力总成悬置系统的耦合特性和加速工况时的瞬态振动,指出了原始设计不合理的地方.在此基础上,以悬置位置与悬置刚度为设计变量,以加速工况悬置处的瞬态动反力为目标函数.运用遗传算法对动力总成悬置系统进行了优化设计,从而有效地改善了动力总成悬置系统的隔振性能.     

ENGINEERING CHARACTERISTICS AND ITS MECHANISM EXPLANATION OF VIBRATORY SYNCHRONIZATION TRANSMISSION

Vibratory synchronization transmission (VST) is a kind of special physical phenomenon ininertia vibration mechanical systems. For an inertia vibration mechancal system driven by one pair ofmotors runs in step, even the power supply of one motor is cut off, the motor can continue to keeprotating state under the vibration exciting of the machine body driven by only one other motor. And itsrotating frequency will be the same as that of the other one. The transient process of this wonderfulphysical phenomenon has not been described quantitatively according to current-existing mechanicalmodels. On the basis of investigation of the engineering characteristics of VST, a mechanical and elec-trical coupling mathematical model of a two-shaft inertia vibration machine is established. With thismodel, the transient process of VST is recurred quantitatively and successfully, and a reasonable ex-planation is given.     

一种研究异步电动机振动的新方法

在理论上建立了异步电动机转矩的模型,提出了异步电动机振动边频结构分析法。并进一步讨论了振动机电调特性和边频带非迭混特性。结合故障实例,对异步电动机的磨损动不平衡和电压波动实测振动信号进行了处理和分析。实验结果与理论结论相一致。因而表明,边频结构分析法是研究异步电动机振动的一种有效方法。它可应用于异步电机振动特征频率的识别、状态监测和故障诊断。     

电力牵引系统异步电动机直接转矩控制仿真

基于电力牵引系统中异步电动机直接转矩控制的基本数学模型,建立了该种异步电动机直接转矩控制系统的Matlab／Simulink仿真模型。通过数值仿真证明了直接转矩控制的优越性。     

Multidisciplinary simulation for driving performance analysis of an escalator system

An electric motor coupled with a gear train generates driving torque to move step band and handrail band together with passenger load for operation. Therefore, understanding of electric motor dynamics and its influence on escalator system in transient and steady state is very important for both product development and service operation in compliance with safety code requirement. A multidisciplinary escalator simulation model in complete system-level is introduced based on multibody dynamics technology including 3-phase induction motor, gear train inside of machine gearbox, step band, handrail band and all other drive chain bands. Torque from 3-phase induction motor is considered in the system model by the flux linkages equations derived from d-q axis equivalent circuit. The verified simulation model compared with Thévenin’s equivalent circuit model is used to investigate driving performance of an escalator system in different passenger load condition.     

基于前馈补偿的效率优化异步电机直接转矩控制

针对异步电机在轻载和高速运行时效率低的问题,提出了一种异步电机直接转矩控制技术的效率优化算法。建立了基于定子磁场定向下旋转坐标系的电机损耗模型,分析了电机损耗与转矩、转速与定子磁链的关系,从而导出稳态时最优的定子磁链幅值,实现电机在不同工况下以最优效率运行。为解决最优磁链计算模块引入后电机控制系统动态响应慢的问题,将伺服电机控制中常用的前馈补偿与速度外环PI调节器相结合,来提高效率优化算法引入后系统的动态性能。     

五自由度磁悬浮电主轴结构与有限元分析

提出一种五自由度稳定悬浮的电主轴,由二自由度磁悬浮异步电机与三自由度轴向混合磁轴承实现五个自由度的稳定悬浮。其中,三自由度混合磁轴承采用四个定子磁极来控制轴向悬浮力与径向扭转力,可有效减少轴向长度。文中介绍了五自由度磁悬浮电主轴工作原理,建立磁悬浮异步电机和混合磁轴承的数学模型,并用电磁场分析软件welll5．0分析其磁场和悬浮力,验证电主轴的可行性,最后运用biatlab软件建立基于转子磁场定向的无轴承异步电机控制系统,仿真结果表明该控制方法可有效稳定控制电机。     

计算机辅助选择电机系统

本软件基于CAES原理 ,利用面向对象的编程技术和数据库开发技术实现了中小型电动机的智能类型选择 ,并对Y系列 (IP4 4 )三相异步电动机以及Y系列 (IP2 3)三相异步电动机的具体技术参数和结构参数选择 ,集成为电机的计算机辅助选择系统。     

City-Bus-Route Demand-based Efficient Coupling Driving Control for Parallel Plug-in Hybrid Electric Bus

Recently,plug?in hybrid electric bus has been one of the energy?e cient solutions for urban transportation. However,the current vehicle e ciency is far from optimum,because the unpredicted external driving conditions are di cult to be obtained in advance. How to further explore its fuel?saving potential under the complicated city bus driving cycles through an e cient control strategy is still a hot research issue in both academic and engineering area. To realize an e cient coupling driving operation of the hybrid powertrain,a novel coupling driving control strategy for plug?in hybrid electric bus is presented. Combined with the typical feature of a city?bus?route,the fuzzy logic inference is employed to quantify the driving intention,and then to determine the coupling driving mode and the gear?shifting strategy. Considering the response deviation problem in the execution layer,an adaptive robust controller for electric machine is designed to respond to the transient torque demand,and instantaneously compensate the response delay and the engine torque fluctuation. The simulations and hard?in?loop tests with the actual data of two typical driving conditions from the real?world city?bus?route are carried out,and the results demonstrate that the pro?posed method could guarantee the hybrid powertrain to track the actual torque demand with 10.4% fuel economy improvement. The optimal fuel economy can be obtained through the optimal combination of working modes. The fuel economy of plug?in hybrid electric bus can be significantly improved by the proposed control scheme without loss of drivability.     

平行于硬盘盘面方向振动主动控制系统仿真分析

平行于硬盘盘面方向,通过微加速度传感器检测外界冲击振动信号,结合硬盘自身的寻道控制系统,采用自适应逆控制算法,提出了附加音圈电机电流的抗冲击振动控制方法。基于Lagrange-Maxwell方程,建立了系统的机电动力学模型。仿真模拟了硬盘寻道过程,对系统的振动控制性能进行了仿真分析,结果验证了该方法的可行性。