分马力(小功率)电机行业运行良好

电机作为机电能量转换的重要装置,是电气传动的基础部件,其耗电量约占全部用电量的60％以上,各类电机在工业自动化应用中．对国民经济、能源利用、环境保护和人民生活质量的提高发挥着重要作用。     

小功率电机在国内外的发展概况

简要综述近年来小功率电机在国内外生产的状况 ,探讨小功率电机的发展趋势 ,并介绍新材料、新元器件在小功率电机中的应用情况。     

分马力电机安全认证工厂审查中企业存在的共性问题

对分马力电机安全认证工厂审查中企业存在的共性问题进行了分析，指出这些总是产生的原因，并提出了解决办法。     

分马力电机产品“十五”市场发展预测

分马力(小功率)电机包括一般用途及专门用途的电动机,如一般工业机械配用及家用电器、办公器械等用电动机.分马力电机应用面广、涉及面宽、生产规模大、引人瞩目,并随着我国国民经济的发展和人民物质生活的提高得到了高速发展.全行业目前有"电机厂"牌子的企业约190家,其中参加中国电机工业协会分马力电机分会的有130家左右;乡镇企业、集体企业及其它行业企业附属的生产分马力电机的厂家有1000多家;合资企业约20多家,大多分布在沿海地区.     

小功率电机行业状况与发展趋势

一、我国小功率电机行业发展状况 1、制造企业的结构、性质与数量 我国小功率电机行业已初步形成了比较完整的产业体系.小功率电机生产及配套厂商约在2000家以上;主机厂商近1000家.规模企业在200家以上.民营企业约占80%左右;外资或合资合作企业约占10%左右,国有、集体或股份制企业在10%左右;行业从业人员近30万人.     

小功率电机在国内外的发展概况

简要综述近年来小功率电机在国内外生产的状况，探讨小功率电机的发展趋势，并介绍新材料、新元器件在小功率电机中的应用情况。     

Rapid parameter determination for induction motor analysis and control

This paper describes the implementation of a rapid online parameter determination method for three-phase induction motors. The technique is based on data sampling during a normal run-up-to-speed test. The method has been refined such that even the normal locked-rotor and synchronous speed data are measured during the run-up test. Furthermore the technique takes into account rotor parameter variations with frequency due to skin effect (mainly due to double-cage or deep-bar rotor), and other nonlinear imperfections such as heating and main flux path saturation. Moreover, the monitoring system, capable of identifying three-phase RMS voltage and current, power, power factor, and speed within one or two sampling periods of less than a few hundred microseconds each, can be used for condition monitoring of any three-phase electrical drive system and can be permanently or temporarily connected to such a system for diagnosis.     

基于分数阶PID控制的永磁直驱电机仿真研究

研究了将一种基于分数阶PID控制的新型控制器引入到永磁直驱同步电机控制当中,取代基于传统工程设计的PI调节器,改善电机的调速性能。在dq同步旋转坐标系下建立了永磁同步发电机组数学模型,通过PWM控制技术得到发电机侧变流器所需的驱动信号,实现功率的传输,运用Matlab/Simulink工具箱对PMSM系统进行仿真。结果表明,验证了所提控制方法的正确性,相对传统PI调节器,分数阶PID控制器的控制系统动态性能优良,鲁棒性好。     

离散分数阶Fourier变换的阶数分解算法

分数阶Fourier变换在科学计算和工程中有广泛应用前景,但现有的离散分数阶Fourier变换（DFRFT）缺乏有效的快速算法。本文给出了一种采用阶数分解的DFRFT算法,由特定阶数DFRFT的加权和可得到任意分数阶域的DFRFT,权系数由DFTHermite本征值和附加零构成序列的离散Fourier反变换（IDFT）得到,且在搜索最佳分数阶域的过程中仅需计算一次IDFT,无需重新计算其所有变换核,从而可有效减少运算量,适合于应用在分数阶域的多分量信号检测和滤波处理中,仿真结果表明了该算法的有效性。     

Online cable monitor developed in Japan

The Japanese high-voltage system is outlined. The OLCM (online cable monitor) method is explained in detail from concept to the developed automatic model. OLCM is the name of the apparatus for monitoring the deterioration state of XLPE cables without interrupting service. With OLCM, it is possible to detect deterioration of XLPE cables having water-trees while the cables are live. Some views on the insulation resistance characteristics of deteriorated XLPE cables following long-term operation of the OLCM are presented     

Newly developed voltage security monitoring system

A voltage security monitoring system has been developed and installed in the energy management system of TEPCO's (Tokyo Electric Power Co.'s) central energy control center. The authors present the background and concept of the developed system, the newly developed algorithm, the configuration of the system and results of actual operation. A PV (total demand, voltage) curve is used for estimating voltage stability. To determine the curve, an algorithm for obtaining multiple load flow solutions is developed. The system has been in operation since February 1990, running at intervals of one minute     

英国开发新型超高效家用灯泡

英国的研究人员近日声称，他们正在开发一种新型超高效家用灯泡，这意味着普通灯泡可能会在不远的将来被取而代之。     

日本研究小组研制出超导发光二极管

日本北海道大学末宗几夫教授领导的研究小组成功开发出实现“量子通信”必不可少的超导发光二极管。     

SGCC successfully developed large-capacity sodium-sulfur monomeric battery

Through many years‘ cooperation,SGCC and Shanghai Silicate Research Institute of Chinese Academy of Science successfully developed 650 ampere-hours capacity sodium-sulfur monomeric storage battery with the independent intellectual property right