新型高效单相感应电动机的设计计算方法研究

作为三相感应电动机单相运行的一种特殊接线方式 ,与三相感应电动机在三相对称电源上运行相比 ,SEMIHEX电动机具有高的功率因数和效率。本文研究了对称运行需要满足的条件 ,采用双旋转磁场理论对其进行分析 ,给出了性能计算的具体方法 ,计算结果和试验结果的吻合 ,证明本文给出的方法是正确有效的。     

A nine‐switch inverter for driving two AC motors independently

This paper presents a nine‐switch inverter that can drive two AC motors independently. Recently, as an inverter that can drive them independently, a five‐leg inverter has been proposed. Ten switching devices are used for the five‐leg inverter, whereas only nine are used for the nine‐switch inverter. So, the nine‐switch inverter has the merit that one switching device can be reduced compared to the five‐leg inverter. Moreover, the maximum output voltage of the nine‐switch inverter equals that of the five‐leg inverter. In this work, we propose the structure of the nine‐switch inverter and a modulation method for the same, and validate the nine‐switch inverter by showing simulation results. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

基于DSP的感应电机直接转矩控制研究

在传统的异步电机直接转矩控制中,在低速时的转矩波动会使控制系统性能变差.这里采用高性能的磁链观测器来准确观测磁链,并且采用转矩与磁链双层滞环比较器来优化改进开关选择表.仿真与实验结果证明本文的控制方案能有效降低低速时的转矩波动.     

机械科学与工程研究中的创新能力

分析探讨了提高科技创新能力的关键要素。创新教育首先要培养创新意识。要用敏锐的洞察力去发现问题、形成并提出问题。要有丰富的知识,以及获取、处理信息并将其转换为知识的能力。要有科学研究的素质和创造性思维的能力。要善于通过高度的科学或哲学概括,建立不同现象间的内在关联,以获得创新。要善于利用发散或反向思维取得创新成果。     

基于光栅信号的步进电机速度控制

在分析步进电机运行特性的基础上 ,讨论了步进电机运行时高速失步和低速波动的原因及其对策 ,研究了转换角和超前角在步进电机速度控制中的作用 ,采用改变光栅反馈脉冲当量角及延时调整转换角的方法进行速度的平稳调节 ,并给出了速度控制方案及其实现     

Transient State Machine Enabled from the Colliding and Coalescence of a Swarm of Autonomously Running Liquid Metal Motors

Internally triggered motion of an object owns important potential in diverse application areas ranging from micromachines, actuator or sensor, to self‐assembly of superstructures. A new conceptual liquid metal machine style has been presented here: the transient state machine that can work as either a large size robot, partial running elements, or just divide spontaneously running swarm of tiny motors. According to need, the discrete droplet machines as quickly generated through injecting the stream of a large liquid metal machine can combine back again to the original one. Over the process, each tiny machine just keeps its running, colliding, bouncing, or adhesion states until finally assembling into a single machine. Unlike the commonly encountered rigid machines, such transient state system can be reversible in working shapes. Depending on their surface tension, the autonomously traveling droplet motors can experience bouncing and colliding before undergoing total coalescence, arrested coalescence, or total bounce. This finding would help mold unconventional robot in the sense of transient state machine that could automatically transform among different geometries such as a single or swarm, small or large size, assembling and interaction, etc. It refreshes people's basic understandings on machines, liquid metal materials, fluid mechanics, and micromotors.     

我国中小型电机制造业市场前景分析

我国将会成为世界电动机,特别是中小电动机的生产制造基地;我国出口电机竞争能力亟待加强,产品开发要与国际接轨,以打入国际市场为主攻方向,从产品质量、外观、性能、安装尺寸、可靠性等方面增强在国际市场的竞争能力;国家优惠政策给电机行业带来了积极的影响     

异步电机软启动控制系统研究

针对传统的两相调压控制系统中存在两组晶闸管选型不一致的问题,本文先对带阻性负载的两相可控交流调压的三相电路,详细分析了负载电压的工作波形。并针对两组晶闸管选型不一致的缺陷提出了一种改进的两相调压软启动控制系统。在MATLAB/simul ink仿真平台上实现了两组晶闸管通电电流一致的控制,控制方式达到了预定的控制效果。     

基于Matlab/Simulink的异步电机直接转矩控制方法的研究

本文通过分析异步电机数学模型,逆变器模型及空间矢量电压的分析来阐明异步电机直接转矩控制方法的原理,基于Matlab/Simulink仿真平台建立异步电机直接转矩控制方法仿真平台,仿真结果表明该控制方法使得系统变得简单,易于实现,具有广泛的应用意义。