220kV母线保护在不同运行方式下的应用

本文以涵江变220kV母线BP-2A保护改造为例,介绍了涵江变母线保护改造前后220kV母线一次接线方式、BP-2A母线保护接线回路的变化及软件修改变化,分析了该母线保护改造前后的优缺点．并提出合理的建议。     

浅谈变电站保护屏屏顶小母线的安装注意事项

鉴于变电站保护屏屏顶小母线安装的重要性,本文从变电站保护屏屏顶小母线安装面临的困难、小母线绝缘问题的处理、母线扁盒制作三方面提出安装注意事项,以预防触电和保护误动事故的发生,确保保护屏屏顶作业的安全。     

母差CT极性对母差保护的影响分析

母线是变电所和发电厂的重要组成部分,发电机、输配电线路、变压器和调相设备均由母线连接,其可靠性直接影响着变电所和发电厂的可靠性。母线保护为母线主保护,如果出现故障,母线则无法及时、准确、可靠地动作,从而影响电力系统的稳定性,造成严重的后果。因此,加强母线保护,确保其正常动作,是确保电力系统稳定运行的重要环节。     

母线保护在变电站母线倒闸操作时的处理

母线系统在保护动作中存在一定的拒动和误动,会给整个电力系统造成不小的危害。母线倒闸是十分常见的操作,需要一定的专业技能素养,才能做好相关操作工作。本文就母线保护的基本原则进行了分析,深入探讨了母线倒闸时母线保护的操作处理,以供参考。     

浅谈母线保护相关技术要求

在电力系统变电站运行过程中,母线是一种非常重要的系统设备之一,对于电力系统的安全运行有着重大的影响和意义。而母线保护作为母线正常运行的有效保障,只有不断对母线保护技术进行深入的改造与完善,才能进一步提高母线的可靠性,从而确保电力系统的可靠运行,促进我国电力事业的蓬勃发展。为此,笔者通过结合多年来的工作经验,主要对母线保护相关技术要求进行了详细的论述,具体介绍了母线保护的重要性、相关技术原则等,并得出以下相关结论,以供参考交流。     

探讨母线保护的故障启动方法

母线保护对于电力系统来说,其是继电保护的重要构成环节。母线在输配电的环节中有很关键的作用,当其发生故障时,会对电力系统造成严重的影响,导致母线连接设备的运行出现异常,产生大面积停电或是设备破坏。随着电力系统的不断发展,母线保护的要求越来越高,对其可靠性、灵敏性和快速性的要求日渐增长。本文对母线保护的基本原理进行了简单分析,深入探讨了母线保护的故障启动方法,以供参考。     

一种适用于N间隔的母差保护装置

大型发电机组中压厂用母线是全厂各类负荷的集中汇集点,其安全运行直接影响机组乃至电网的安全运行。近年来,开关柜故障造成母线"火烧连营",甚至造成机组跳闸、人身伤亡事故接连发生,因此,实现发电厂中压母线快速保护迫在眉睫。从火力发电机组中压母线保护现状及存在问题为出发点,设计一种适用于N间隔的母差保护装置,彻底解决母线快速保护难题。     

弧光保护在电网应用中存在的问题及解决方案

在35kV及以下电压等级电网的母线正逐步应用弧光保护。为了提高可靠性,六盘水供电局某些变电站应用弧光保护时就采用“电弧光和电源二次电流”双判据、并为每段母线配置一套弧光保护装置的方案。但这种方案存在死区问题,即当一台变压器带35kV或10kV两段母线负荷并列运行时,若Ⅱ段母线上发生故障,Ⅰ段母线弧光保护将因检测不到弧光而不能动作,Ⅱ段母线弧光保护将因检测不到电流而不能动作,Ⅰ段母线故障时存在同样问题。本文对该问题展开分析,论述了“电流或逻辑”的解决方案,即弧光保护装置同时采集进线电源断路器与分段断路器的电流互感器的二次电流,只要有任意一个电流满足弧光保护电流判据时电弧光也满足要求,弧光保护即可动作。     

态势评估方法在水电仿真系统应用

针对水电仿真系统中母线保护规则冗余、通用性差,保护过程复杂性高等问题,本文将信息融合技术的态势评估模型应用于母线保护系统中。通过对多信源数据的实时采集,在态势评估过程中以粗糙集理论进行母线系统领域知识的自动获取,利用改进的黑板模型实现动态运行环境下的母线系统的实时保护功能。经在吉林丰满水电仿真系统的实验,验证了该模型的有效性和实际应用价值。     

数字化变电站10kV母线保护方案研究

中压母线在发生短路故障时产生的电弧光对设备及人员造成极大的损害，为了满足继电保护快速性的要求，在一些重要的变电站中压母线配置专用的母线保护。目前数字化变电站的建设已由理论研究走向工程实践阶段，本文结合数字化变电站的建设提出了几种中压母线保护的解决方案。     

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。     

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.     

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     

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.