浅谈IEC61850规约在工程现场的应用

IEC61850是新一代的变电站自动化系统的国际标准,它规范了数据的命名、数据的定义、设备行为、设备的自描述特征和通用配置语言。同传统的IEC60870-5-103标准相比,它不仅仅是一个单纯的通信规约,而是数字化变电站自动化系统的标准,它指导了变电站自动化的设计、开发、工程、维护等各个领域。该标准通过对变电站自动化系统中的对象统一建模,采用面向对象技术和独立于网络结构的抽象通信服务借口,增强了设备之间的互操作性,可以在不同厂家的设备之间实现无缝连接。智能化一次设备和数字式变电站要求变电站自动化采用IEC61850标准。IEC61850是至今为止最为完善的变电站自动化标准,它不仅规范保护测控装置的模型和通信接口,而且还定义了数字式CT、PT、智能开关等一次设备的模型和通信接口。采用IEC61850国际标准可以大大提高变电站自动化技术水平、提高变电站自动化安全稳定运行水平,节约开发验收维护的人力物力,实现完全的互操作。本文结合工程现场实例探讨IEC61850在工程中的基本应用。     

基于IEC61850标准的数字化变电站电能计量系统

本文介绍了IEC61850标准和数字化变电站的电能计量系统的结构组成,随着IEC61850标准在变电站中推广应用,作为变电站重要组成部分的电能计量系统也需要设备信息数据的数字化、通信网络的标准化,以适应数字化变电站发展需要。     

IEC61850数字化变电站的描述

在深入研究IEC61850协议的基础上介绍了IEC61850的通信体系及特点,并阐述了作者对IEC61850标准的认知和与目前变电站系统进行比较,综合介绍了本标准应用于数字变电站的优势及存在的问题,使对IEC61850有更深一步认识。     

探讨移动变电站远程监控系统

随着社会经济的不断发展,科学技术水平的不断提高,移动变电站作为一种重要应急供电设备,在突发重大自然灾害、设备更新改造时有着重要作用。现阶段,大多数变电站其通信接口主要在IEC 61850标准基础上形成的,在此基础上,移动变电站远程通信概念基于IEC 61850标准面向通用对象的变电站事件模型,构建远程监控系统。     

智能变电站通用报文解析器设计

本文介绍了智能变电站中各种数字报文信息,设计了针对智能变电站的通用报文解析器,对智能变电站中的GOOSE报文、采样值SV报文、MMS报文以及远动IEC60870-5-104规约报文进行实时记录、分析,并以图形化的界面展示分析结果,方便运维人员能及时、形象的了解二次设备的运行状态,提高运维水平。     

浅谈35kV数字化变电站关键技术

摘要：常规变电站的数字化改造是当前电网数字化建设的热点,近年来新型电子式互感器技术、IEC61850标准、数字断路器及网络通信技术的日趋成熟,为解决常规变电站向数字化方向发展提供了技术保证。本文提出基于IEC61850—9过程层解决方案,设备接口支持IEC61850间隔层解决方案,对内支持集中1EC61850、对外配置规约转换功能的站控层解决方案以及站控层与过程层网络分设、过程层分采样点对点和独立GOOSE网络的组网解决方案。最后,本文以35kV常规变电站数字化改造项目为对象,进行方案实践,验证了方案具有可行、经济和稳定运行等方面的优势,能够满足35kV变电站数字化需求。同时,给出实践中遇到的试验调试过程的解决方法。提出方案的优化措施。     

基于IEC61850的数字化变电站技术

电子行业的数字化技术飞速发展,工商界的许多领域都正在进行数字化革新。可以预计,随着技术的发展,每套设备、每个插座和开关甚至每盏白炽灯都将具有设置、监测以及控制功能。为了管理众多器件并且使这些器件互相通信,需要一种新型的通信模式。这种通信模式以变电站IEC61850通信网络和系统作为标准。随着IEC61850标准的不断推广,变电站技术也得到迅速发展。基于IEC61850的数字化变电站逐渐得到应用。本文阐述了IEC61850的内容和特点,分析了数字化变电站的结构,并指出数字化变电站建设是变电站未来发展的必然趋势。     

IEC61850的分布式母线保护方案

主要研究IEC61850的分布式母线保护方案,对IEC61850标准进行了分析,并建立了一套基于IEC61850的分布式母线保护方案,对变电站综合自动化设计有着一定的帮助。     

新型数字化变电站光纤纵差保护同步方法分析与设计

随着现代科技智能化电气的发展,变电站自动化技术进入了数字化时代,数字化变电站技术是以IEc61850标准为基础发展起来的。在IEC61850．9-1/2通信标准的数字化变电站中,光纤纵差线路保护装置的关键技术是解决两侧电气量的同步。针对这一问题,本文提出了数字变电站线路差动保护基于乒乓原理的定时中断同步的采样同步调整方案,并分析了基于该同步时差动保护性能和互操作的解决措施。从而实现两侧电气量的同晓     

智能变电站二次设备集成方案探析

在IEC 61850标准的应用背景下,现代变电站中网络采样技术的应用有效推动了其智能化发展方向,同时也加快了二次设备的集成进度,使设备控制更加先进化与自动化,实现了"高效、价低以及占地少"的新一代智能变电站的发展。鉴于此,以现代智能变电站为论述对象,以二次设备的集成方案为论述手段,就此展开专业分析。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.     

Cooler temperatures inductive to locust outbreaks

Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence     

Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels

<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese     

More than Skin Deep – Understand Skin Biology by Means of Dermatogenomics

<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages.