一种减少SRM转矩脉动的控制策略研究

开关磁阻电机(SRM)由于其简单的结构和优异的性能,应用范围很广泛,但其本身结构导致了转矩脉动的产生,为了解决这个问题,文章研究了一种控制策略—直接转矩控制,以减少开关磁阻电机的转矩脉动。文章详细阐述了直接转矩控制的基本原理和实现方法,并对基于这种控制策略的开关磁阻电机的控制进行了Matlab仿真。仿真结果表明直接转矩控制能够有效地减少开关磁阻电机的转矩脉动,且控制方法简单,系统具有良好的动静态性能。     

一种开关磁阻电机无位置传感器控制方法的实现

开关磁阻电机位置传感器的使用,增加了结构的复杂性,降低了控制的可靠性,因此脱离传感器的无位置控制技术成为了国内外专家学者研究的热点之一。分析开关磁阻电机的工作原理,并结合国内外有关开关磁阻电机无位置传感器转子位置检测和调速控制的相关文献,总结得到一种简单的开关磁阻电机无位置传感器控制方法。仿真和实验结果表明,该方法能够实现对无位置传感器开关磁阻电机的有效控制。     

基于单片机的开关磁阻电机驱动系统设计

该文介绍了开关磁阻电机的基本原理,设计了一种用80C196单片机实现的开关磁阻电机驱动系统,并对该开关磁阻电机调速系统的性能进行了实验与测试,实验证明该系统运行可靠。     

基于MCU和CPLD的开关磁阻电机控制器的设计

以MCU和CPLD为核心,研制了一种通用的开关磁阻电机控制器,与开关磁阻电机一起组成宽调速范围、高效节能的开关磁阻电机调速系统,克服了直流和交流电机调速系统的一些缺点,实践证明,该系统能很好地应用于各种通用调速场合,具有成本低、控制灵活、自适应能力强及适用范围广等优点.     

开关磁阻电机控制系统仿真建模研究

基于开关磁阻电机的基本方程式,利用Madab/Simulink环境下的基本模块,搭建了一个开关磁阻电机驱动系统的动态仿真模型.可以对给定参数的开关磁阻电机的动态特性进行仿真.仿真结果证明了开关磁阻电机建模方法的合理性、有效性,为实际电机控制系统的设计和调试提供了新的思路.     

开关磁阻电机发电原理与仿真研究

本文介绍了一种新型六相12/10极开关磁阻电机,对发电运行原理进行了分析,并利用Ansoft公司的RMxprt和Maxwell2D瞬态模块对开关磁阻电机发电系统进行建模,对正常和缺相两种运行状态下的发电性能进行了动态仿真分析,通过与三相6/4极开关磁阻电机发电性能进行比较,验证了新型开关磁阻电机在发电运行时具有更好的安全欲度,说明了相数对安全欲度的影响.     

PIC16F1508的开关磁阻电机伺服系统设计

本文以PIC16F1508单片机为控制核心,利用其PWM模块、CLC模块、TMR1模块的组合进行脉宽调制和速度检测,使用开关磁阻电机专用驱动功率芯片FCAS20DN60BB作为驱动,实现对开关磁阻电动机的伺服控制。本控制系统结构简单,减少了外部逻辑器件的使用,并且提高了系统的可靠性、大大降低了系统的成本。通过使用370W、四相8/6极开关磁阻电机作为控制对象,取得了较好的实验效果。     

开关磁阻电机高性能闭环调速系统仿真

在提高开关磁阻电机调速控制的精确度的研究中,由于系统存在非线性,调速精度低.利用传统控制方法进行开关磁阻电机调速的过程中,由于开关磁阻电机是双凸极结构,其电磁特性呈现高度的非线性,参数和结构也是在时刻变化的,不存在有效的反馈,造成固定参数的传统的开环调速控制方法的调速精确度较低.提出一种闭环控制的开关磁阻电机调速方法.利用线性法对开关磁阻电机中的相关控制变量进行分析,建立控制系统模型,以实际电流和参考电流的偏差作为调速过程中的反馈,等效控制开关磁阻电机绕组中的相电压,通过改变反馈参数对绕组中的相电压进行调节,从而实现开关磁阻电机调速过程中的闭环控制.实验结果表明,改进算法能够有效提高开关磁阻电机转速控制的精确性.     

开关磁阻电机调速系统及其应用

本文介绍了开关磁阻电机调速系统的发展概况及基本构成,并对开关磁阻电机调速原理进行分析,最后详细阐述了该系统作为一种新型调速系统的优点及其应用.     

基于角度优化的开关磁阻轮毂电机发电回馈控制策略研究

开关磁阻轮毂电机简单、工作可靠、效率高,应用于电动汽车具有很大应用潜力,但由于其严重的非线性,数学模型难以建立。通过分析开关磁阻轮毂电机制动发电和能量回馈工作原理,找到影响发电效率的主要因素,通过模糊控制调节开通角、关断角度实现角度优化,提高开关磁阻轮毂电机发电效率。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

A human-computer interface for non-computer specialists

The COM teleconferencing system was designed to be easy to use for both beginners and people with much computer experience. A number of design choices in organizing the human-computer interface were considered very carefully. These design problems are not unique for teleconferencing applications, but will appear in many other developments of human-computer interfaces for non-computer specialists. This report discusses naming conventions, menu format, user commands, help facility and the treatment of ‘type ahead’ from the users.