发电厂电气系统综合自动化

1、Integrated Auto mation of Power Plant Electrical System1IntroductionIntegrated automation technology has been applied in power system substations, and decentralized and distributed technology1is widely used in integrated automationsystem.Comparedtothecentralized technology,this technology has many a

2、dvantages such as simple and flexible structure,high reliability,convenient installation and low cost of maintenance.However,integrated automation technology has not been widely used in power plant electrical system.Protective relay and security devices of electrical system run in a self9-governed s

3、tate,which havent formed an integrated electrical automation system.Therefore The managing and maintaining level hang behind.Latterly more and more power plants,especially those newly constructed are interested in the automation of power plant electrical system and its relationship with traditional

4、distributed control system(DCS.This paper analyzes the actuality of power plant electrical system,brings out a new ideal of application ofmicrocomputer9-basedintegratedautomation technology to power plant electrical system,and gives concrete realization of the program.2The status of power plant elec

5、trical systemThe electrical system discussed in this paper is mainly referred to the protection, measurement,control and automatic devices of secondary system.Main protection devices include generator protection,main transformer protection and start up/stand by transformer protection.Automatic devic

6、es include automatic regulator voltage (AVR,automatic transfer switch(ATS,faultkymograp hand protection includes high-voltage motor low-voltage system includes auto-low-voltage intelligent motor protector,breaker,DC system,etc2water system are not included.The characteristics of electrical system3op

7、eration frequency than thermal microcomputer and large-adopted.mainly on steam9-electricalsystem.“Hardcable”.exchange is limited on account of the cost.impossible to accomplish more complex electrical data.Aiming at the comparatively laggard level of power plant electrical system automation,this pap

8、er analyzes the feasibility, necessity and some key points of the application of integrated automation technology to power plant electrical system.New idea using fieldbus control system technology is presented.This paper also gives the outline and detailed antomatic synchronization system(ASS.6kV au

9、xiliary power integrative protection device, auxiliary transformer integrative protection device,feeder protection device,etc.400 V changeover device,intelligent.All these belong to the electrical system.The common systems such as coalhandling system,ash handling system and chemical are that electri

10、cal equipments have less control objects;lowersystem devices.Electrical devices have high reliability and swift action time.The technology level of individual electrical device is high.Presently,16or32bit single-chip scale programmable logic chip are used to build embedded system.Technologies of AC

11、sampling and digital signal process are also widely DCS is widely used in power plants,and it fulfills basic operation and control functions.DCS concerns boiler system meanwhile little on Traditionally,control and signal exchange between DCS and electrical system is through this connection mode need

12、s manycables,and the cost is high.Besides,the information It is electric operation management or achieve deep application of Since DCS is the most important system in power3Feasibility Analysis of Electrical System Integrated AutomationThe improvement of electrical system automation is based on inte

13、grated automation and field bus or industrial Ethernet technology.Microcomputer9-based protection and automation devices are widely used in power plant electrical system.The measure,logic judge,action,record and man9-machine interface function can be done by software.Moreover,all these devices have

14、communication interface,they can exchange information with master system or with each other through field bus.Fieldbus technology has been widely used in industry and electric power field, and it has been paid more and more attention.The technology in communication rate,communication distance and an

15、ti jamming capability has been improved.Many sorts of standards have been formed,such as Profibus advocated by Siemens,FF by ABB,CAN originated from automobile industry and Lon works brought forward by Echelon company.They are all influential fieldbus technology and applied in industry automation ar

16、ea4.Recently,industrial Ethernet network becomes new hotspot.The application of microcomputer-based devices of electrical system,fieldbus or industrial Ethernet technology and communication capability provided by DCS system bring powerful support for the integrated automation of power plant electric

17、al system.4Real inaction of Integrated Automation in Electrical System Electrical system integrated automation is to connect foregoing many protective relay and automation devices by fieldbus and then connect them to DCS system and (possibleelectrical workstation through communication devices.The el

18、ectrical workstation implements all the electrical application such as monitoring and maintenance function,and the basic Control function is accomplished by DCS system using“hard cable”.With the development of technology,the control function can also be fulfilled by communication.Thereare two main p

19、roblems in building integrated electrical automation system.One is how to build the electrical system network;the other is how to connect electrical system with DCS.Fieldbus standard is the main problem in building the network.Due to the protection and automation devices produced by different manufa

20、cturers,the physical layer and communication protocol may be different,so the devices cannot be connected simply.Since it is difficult to unify the fieldbus standard,one way to solve this problem is to divide electrical system into several subsystems.According to the electrical system feature,the su

21、bsystem can be divided into6kV subsystem,400V subsystem,generator9-transformer protection subsystem and AVR subsystemetc.Each subsystem supports the same fieldbus standard.For example,feeder protection,motor protection,transformer protection on6kV bus must support one kind of standard.Protections of

22、400V System or intelligent circuit breaker use the same standard.Generator transformer protection and AVR can have the same or different standards.5ConclusionAdopting integrated automation of power plant electrical system is the tendency of improving the automation level of power plant,especiallyimp

23、roving electric operation management level.It will save the investment and improve the reliability.Microcomputer protection,automatic device,maturecommunication and fieldbus technology are the technical guarantees forintegrated automation of electrical system.This paper puts forward two schemes of i

24、ntegrated automation of electrical system.But the modes of connecting with DCS,standard of filedbus and structureof communication network,are still under research and need more practice.发电厂电气系统综合自动化1引言综合自动化系统已经被应用于变电站系统中,并且分散分配技术也被广泛地用于综合自动化系统中。与集中的技术相比较这种技术有许多的优点,比如:它有简单和柔韧的结构,高的可靠性,方便的安装和较低的成本。然而,

25、综合自动化技术并没有广泛的用于发电厂电气系统中。电力系统中起保护作用的继电器和其他安全设备处于半自动运行状态,并没有实现综合自动化。因此,管理和维持高水平的工作就落后了。后来,越来越多的电厂特别是那些新建的电厂热忠于电气综合自动化系统而不是传统的集散控制系统。这篇论文分析的是发电厂电气系统的现状以及提出了基于微型计算机技术的发电厂电气系统综合自动化的理想应用程序,并给出了具体实现方案2发电厂电气系统的现状电气系统自动化的进步是建立在综合自动化和现场总线或以太网络工艺学基础之上的。以微型计算机为基础的保护和自动化设备被广泛地应用在电厂电气系统中。测量,逻辑判断,动作记录和人-机界面的功能都可以由软件来完成。并且,所有这些设备都具有通信界面,能够和主系统或其他系统之间通过现场总线进行信息交换。现场总线控制技术目前已被广泛用于工业和电力系统中,并且这项技术越来越受到重视。现场总线控制系统的通信速率,通信距离,抗干扰能力都有了极大的改善。其许多标准也被制定,如西门子公司的Pr