电气工程及其自动化外文翻译--继电保护发展现状

电气工程及其自动化外文翻译--继电保护发展现状
电气工程及其自动化外文翻译--继电保护发展现状

毕业设计(外文翻译材料)

学院:专业:学生姓名:指导教师:电气与电子工程学院电气工程及其自动化

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Relay protection development present situation

Abstract: Reviewed our country electrical power system relay protection technological development process, has outlined the microcomputer relay protection technology achievement, propose the future relay protection technological development tendency will be: Computerizes, networked, protects, the control, the survey, the data communication integration and the artificial intellectualization.

Key word: relay protection, present situation development, future development

1 relay protection development present situation

The electrical power system rapid development to the relay protection propose unceasingly the new request, the electronic technology, computer technology and the communication rapid development unceasingly has poured into the new vigor for the relay protection technology development, therefore, the relay protection technology is advantageous, has completed the development 4 historical stage in more than 40 years time.

After the founding of the nation, our country relay protection discipline, the relay protection design, the relay manufacture industry and the relay protection technical team grows out of nothing, has passed through the path in about 10 years which advanced countries half century passes through. The 50's, our country engineers and technicians creatively absorption, the digestion, have grasped the overseas advanced relay protection equipment performance and the movement technology , completed to have the deep relay protection theory attainments and the rich movement experience relay protection technical team, and grew the instruction function to the national relay protection technical team's establishment. The relay factory introduction has digested at that time the overseas advanced relay manufacture technology, has established our country relay manufacturing industry. Thus our country has completed the relay protection research, the design, the manufacture, the movement and the teaching complete system in the 60's. This is a

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time which the mechanical and electrical relay protection prospers, was our countries relay protection technology development has laid the solid foundation.

From the end of the 50's, the transistor relay protection was starting to study. In the 60's to the 80's,it is the times which the transistor relay protection vigorous development and widely used. Tianjin University and the Nanjing electric power automation plant cooperation research 500kV transistor direction high frequency protection the transistor high frequency block system which develops with the Nanjing electric power automation research institute is away from the protection, moves on the Gezhou Dam 500kV line , finished the 500kV line protection to depend upon completely from the overseas import time.

From the 70's, start based on the integration operational amplifier integrated circuit protection to study. Has formed the completely series to at the end of 80's integrated circuit protection, substitutes for the transistor protection gradually. The development, the production, the application the integrated circuit protects which to the beginning of the 90's still were in the dominant position, this was the integrated circuit protection time. The integrated electricity road work frequency conversion quantity direction develops which in this aspect Nanjing electric power automation research institute high frequency protected the vital role, the Tianjin University and the Nanjing electric power automation plant cooperation development integrated circuit phase voltage compensated the type direction high frequency protection also moves in multi- strip 220kV and on the 500kV line.

Our country namely started the computer relay protection research from the end of the 70's, the institutions of higher learning and the scientific research courtyard institute forerunner's function. Huazhong University of Science and Technology, southeast the university, the North China electric power institute, the Xian Jiao tong University, the Tianjin University, Shanghai Jiao tong University, the Chongqing University and the Nanjing electric power automation research institute one after another has all developed the different principle, the different pattern microcomputer protective device. In 1984 the original North China electric power institute developed

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the transmission line microcomputer protective device first through the evaluation and in the system the find application, had opened in our country relay protection history the new page, protect the promotion for the microcomputer to pave the way. In the host equipment protection aspect, the generator which southeast the university and Huazhong University of Science and Technology develop loses magnetism protection, the generator protection and the generator? Bank of transformers protection also one after another in 1989、1994 through appraisal and investment movement. The Nanjing electric power automation research institute develops microcomputer line protective device also in 1991 through appraisal. The Tianjin University and the Nanjing electric power automation plant cooperation development microcomputer phase voltage compensated the type direction high frequency protection, the Xian Jiao tong University and the Xuchang Relay Factory cooperation development positive sequence breakdown component direction high frequency protection also one after another in 1993, in 1996 through the appraisal. Here, the different principle, the different type microcomputer line and the host equipment protect unique, provided one batch of new generation of performance for the electrical power system fine, the function has been complete, the work reliable relay protection installment. Along with the microcomputer protective device research, in microcomputer aspect and so on protection software, algorithm has also yielded the very many theories result. May say started our country relay protection technology from the 90's to enter the time which the microcomputer protected.

2 relay protections future development

The relay protection technology future the tendency will be to computerizes, networked, the intellectualization, will protect, the control, the survey and the data communication integration development.

2.1 computerizes

Along with the computer hardware swift and violent development, the microcomputer protection hardware also unceasingly is developing. The original

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North China electric power institute develops the microcomputer line protection hardware has experienced 3 development phases: Is published from 8 lists CPU structure microcomputer protection, does not develop to 5 years time to the multi- CPU structure, latter developed to the main line does not leave the module the big modular structure, the performance enhances greatly, obtained the widespread application. Huazhong University of Science and Technology develops the microcomputer protection also is from 8 CPU, develops to take the labor controlling machine core partially as the foundation 32 microcomputers protection.

The Nanjing electric power automation research institute from the very beginning has developed 16 CPU is the foundation microcomputer line protection, obtained the big area promotion, at present also is studying 32 protections hardware system. Southeast the university develops the microcomputer host equipment protects the hardware also passed through improved and the enhancement many times. The Tianjin University from the very beginning is the development take more than 16 CPU as the foundation microcomputer line protection, in 1988 namely started to study take 32 digital signals processor (DSP) as the foundation protection, the control, the survey integration microcomputer installment, at present cooperated with the Zhuhai automatic equipment company develops one kind of function complete 32 big modules, a module was a minicomputer. Uses 32 microcomputers chips only to focus by no means on the precision, because of the precision the a/d switch resolution limit, is surpassed time 16 all is accepts with difficulty in the conversion rate and the cost aspect; 32 microcomputers chips have the very high integration rate more importantly, very high operating frequency and computation speed, very big addressing space, rich command system and many inputs outlet. The CPU register, the data bus, the address bus all are 32, has the memory management function, the memory protection function and the duty transformation function, and (cache) and the floating number part all integrates the high speed buffer in CPU.

The electrical power system the request which protects to the microcomputer enhances unceasingly, besides protection basic function, but also should have the

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large capacity breakdown information and the data long-term storage space, the fast data processing function, the formidable traffic capacity, with other protections, the control device and dispatches the networking by to share the entire system data, the information and the network resources ability, the higher order language programming and so on. This requests the microcomputer protective device to have is equal to a pc machine function. In the computer protection development initial period, once conceived has made the relay protection installment with a minicomputer. At that time because the small machine volume big, the cost high, the reliability was bad, this tentative plan was not realistic. Now, with the microcomputer protective device size similar labor controlling machine function, the speed, the storage capacity greatly has surpassed the same year small machine, therefore, made the relay protection with complete set labor controlling machine the opportunity already to be mature, this will be one of development directions which the microcomputer protected. The Tianjin University has developed the relay protection installment which Cheng Yong tong microcomputer protective device structure quite same not less than one kind of labor controlling machine performs to change artificially becomes. This kind of equipment merit includes: has the 486pc machine complete function, can satisfy each kind of function request which will protect to current and the future microcomputer. size and structure and present microcomputer protective device similar, the craft excellent, quakeproof, guards against has been hot, guards against electromagnetic interference ability, may move in the very severe working conditions, the cost may accept. Uses the STD main line or the pc main line, the hardware modulation, may select the different module willfully regarding the different protection, the disposition nimble, and is easy to expand.

Relay protection installment, computerizes is the irreversible development tendency. How but to satisfies the electrical power system request well, how further enhances the relay protection the reliability, how obtains the bigger economic efficiency and the social efficiency, still must conduct specifically the thorough research.

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2.2 networked

The computer network has become the information age as the information and the data communication tool the technical prop, caused the human production and the social life appearance has had the radical change. It profoundly is affecting each industry domain, also has provided the powerful means of communication for each industry domain. So far, besides the differential motion protection and the vertical association protection, all relay protections installment all only can respond the protection installment place electricity spirit. The relay protection function also only is restricted in the excision breakdown part, reduces the accident to affect the scope. This mainly is because lacks the powerful data communication method. Overseas already had proposed the system protection concept, this in mainly referred to the safe automatic device at that time. Because the relay protection function not only is restricted in the excision breakdown part and the limit accident affects the scope (this is most important task), but also must guarantee the entire system the security stable movement. This requests each protection unit all to be able to share the entire system the movement and the breakdown information data, each protection unit and the superposition brake gear in analyze this information and in the data foundation the synchronized action, guarantees the system the security stable movement. Obviously, realizes this kind of system protection basic condition is joins the entire system each main equipment protective device with the computer network, that is realization microcomputer protective device networked. This under the current engineering factor is completely possible.

Regarding the general non- system protection, the realization protective device computer networking also has the very big advantage. The relay protection equipment can obtain system failure information more, then to the breakdown nature, the breakdown position judgment and the breakdown distance examination is more accurate. Passed through the very long time to the auto-adapted protection principle research, also has yielded the certain result, but must realize truly protects to the system movement way and the malfunction auto-adapted, must obtain the more

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systems movement and the breakdown information, only then realization protection computer networked, can achieve this point.

Regarding certain protective device realization computer networking also can enhance the protection the reliability. The Tianjin University in 1993 proposed in view of the future Three Gorges hydroelectric power station 500kv ultrahigh voltage multi-return routes generatrix one kind of distributional generatrix protection principle, developed successfully this kind of equipment initially. Its principle is disperses the traditional central generatrix protection certain (with to protect generatrix to return way to be same) the generatrix protection unit, the dispersible attire is located in on various return routes protection screen, each protection unit joins with the computer network, each protection unit only inputs this return route the amperage, after transforms it the digital quantity, transmits through the computer network for other all return routes protection unit, each protection unit acts according to this return route the amperage and other all return routes amperage which obtains from the computer network, carries on the generatrix differential motion protection the computation, if the computed result proof is the generatrix interior breakdown then only jumps the book size return route circuit breaker, Breakdown generatrix isolation. When generatrix area breakdown, each protection unit all calculates for exterior breakdown does not act. This kind the distributional generatrix protection principle which realizes with the computer network has the high reliability compared to the traditional central generatrix protection principle. Because if a protection unit receives the disturbance or the miscalculation when moves by mistake, only can wrongly jump the book size return route, cannot create causes the generatrix entire the malignant accident which excises, this regarding looks like the Three Gorges power plant to have the ultrahigh voltage generatrix the system key position to be extremely important.

By above may know, microcomputer protective device may enhance the protection performance and the reliability greatly, this is the microcomputer protection development inevitable trend.

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2.3 protections, control, survey, data communication integrations

In realization relay protection computerizing with under the condition, the protective device is in fact a high performance, the multi-purpose computer, is in an entire electrical power system computer network intelligent terminal. It may gain the electrical power system movement and breakdown any information and the data from the net, also may protect the part which obtains it any information and the data transfer for the network control center or no matter what a terminal. Therefore, each microcomputer protective device not only may complete the relay protection function, moreover in does not have in the breakdown normal operation situation also to be possible to complete the survey, the control, the data communication function that is realization protection, control, survey, data communication integration.

At present, in order to survey, the protection and the control need, outdoor transformer substation all equipment, like the transformer, the line and so on the secondary voltage, the electric current all must use the control cable to direct to . Lays the massive control cable not only must massively invest, moreover makes the secondary circuit to be extremely complex. But if the above protection, the control, the survey, the data communication integration computer installation, will install in outdoor transformer substation by the protection device nearby, by the protection device voltage, the amperage is changed into after this installment internal circulation the digital quantity, will deliver through the computer network, then might avoid the massive control cable. If takes the network with the optical fiber the transmission medium, but also may avoid the electromagnetic interference. Now the optical current transformer (OTA) and the optical voltage transformer (OTV) in the research trial stage, future inevitably obtained the application in the electrical power system. In uses OTA and in the OTV situation, the protective device should place is apart from OTA and the OTV recent place, that is should place by the protection device nearby. OTA and the OTV light signal inputs after this integration installment in and transforms the electrical signal, on the one hand serves as the protection the computation judgment; On the other hand took the survey quantity, delivers through

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the network. May to deliver from through the network by the protection device operation control command this integrated installment, carries out the circuit breaker operation from this the integrated installment. In 1992 the Tianjin University proposed the protection, the control, the survey, the correspondence integration question, and has developed take the tms320c25 digital signal processor (DSP) as a foundation protection, the control, the survey, the data communication integration installment.

2.4 intellectualizations

In recent years, the artificial intelligence technology like nerve network, the genetic algorithms, the evolution plan, the fuzzy logic and so on all obtained the application in electrical power system each domain, also started in the relay protection domain application research. The nerve network is one non-linear mapping method, very many lists the complex non-linear problem with difficulty which the equation or solves with difficulty, the application nerve network side principle may be easily solved. For example exhibits in the situation in the transmission line two sides systems electric potential angle to occur after the transition resistance short-circuits is a non-linear problem, very difficult correctly to make the breakdown position from the protection the distinction, thus creates moves by mistake or resists to move; If thinks after the network method, passes through the massive breakdowns sample training, so long as the sample centralism has fully considered each kind of situation, then in breaks down time any all may correctly distinguish. Other likes genetic algorithms, the evolution plan and so on also all has its unique solution complex question the ability. May cause the solution speed these artificial intelligence method suitable unions to be quicker? The Tianjin University carries on the nerve network type relay protection from 1996 the research, has yielded the preliminary result. May foresee, the artificial intelligence technology must be able to obtain the application in the relay protection domain, by solves the problem which solves with difficulty with the conventional method.

3 conclusions

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Since the founding of China's electric power system protection technology has undergone four times. With the rapid development of power systems and computer technology, communications technology, relay technology faces the further development of the trend. Domestic and international trends in the development of protection technologies: computerization, networking, protection, control, measurement, data communications integration and artificial intelligence, which made protection workers difficult task, but also opened up the activities of vast.

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继电保护发展现状

摘要:回顾我国电力系统继电保护技术的发展过程,概述了微机继电保护技术成果,提出了未来继电保护技术的发展趋势将是:计算机化,网络化,保护,控制,调查,数据通信一体化和人工智能化。

关键词:继电保护,目前发展形势,未来发展

1继电保护发展现状

电力系统继电保护的快速发展不断提出新的要求,电子技术,计算机技术和通信技术的快速发展,不断给继电保护技术的发展注入新的活力,因此,继电保护技术是有利的,在短短40多年的发展时间内,经历了4个历史阶段。

建国之后,我国继电保护学科,继电保护设计,继电器制造工业和继电保护技术队伍从无到有,大约10年的时间就已经完成,然而在发达国家需要半个多世纪才能完成。50年代,我们国家的工程师和技术人员创造性地吸收,消化,并掌握了国外先进的继电器保护设备性能和运动技术,完成深继电器保护理论造诣和具有经验丰富的运动继电器保护技术团队,对全国继电保护技术队伍的建立的起了指导作用。当时继电器厂引进消化国外先进的继电器制造技术,建立了我国继电器制造业。因此,我们国家在60年代就已经完成了继电保护研究,设计,制造,运动和教学的完整体系。这是一个机械和电气继电保护繁荣的时代,为我国继电保护技术的发展奠定了坚实的基础。

从50年代末,晶体管继电保护已经开始在我国研究。在60年代到80年代中是晶体管继电保护蓬勃发展和广泛应用的时代。天津大学与南京电力自动化设备合作研究500kV晶体管方向高频保护的晶体管高频块与南京电力自动化研究院开发的系统是远离的保护,对葛洲坝500 kV线路进行操作,开始进入500kV 线路保护完全不依靠从国外进口的重要时代。

从70年代开始,是基于集成运算放大器的集成电路保护研究。在80年代集成电路的保护,逐渐取代晶体管保护,最终已形成完整的系列。集成电路保护的开发,生产,应用到90年代仍然占主导地位,这是集成电路保护的时代。集成电路的工作变频量的方向发展,在这方面,南京电力自动化研究院高频保

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护起着的重要作用,天津大学与南京电力自动化设备合开发的集成电路相电压补偿式高频方向保护在多条220kV和500kV线路上得到应用。

我国从70年代末即开始在计算机继电保护方面的研究,高等院校和科研院体现出了先进的功能。华中科技大学,东南大学,华北电力学院,西安交通大学,天津大学,上海交通大学,重庆大学和南京电力自动化研究的研究所后,根据在不同的原则,不同的模式上,另一种微机保护装置开始出现。1984年原华北电力学院研制的输电线路微机保护装置首先通过鉴定,并在系统中找到应用程序,打开了我国继电保护历史新的一页,为微机保护的推广铺平了道路。在主机设备的保护方面,东南大学和华中科技大学开发的发电机失去磁保护技术,发电机保护和发电机、变压器保护也相继于1989年,1994年通过鉴定,投入到运行之中。南京电力自动化研究院开发微机线路保护装置也于1991年通过鉴定。天津大学与南京电力自动化设备合作开发微机相电压补偿式方向高频保护,西安交通大学与许昌继电器厂合作开发正序击穿分量方向高频保护,也相继于1993年,1996年通过鉴定。在不同的原则,不同类型的微机线路和主设备保护独特之上,又提供了一批新的新一代电力系统的优良性能,功能已经完善,工作可靠的继电保护装置。随着微机保护装置的研究,在微电脑方面等保护软件,算法上也取得了很多的理论结果。

可以说从90年代开始我国继电保护技术进入微机保护的时代。

2继电保护的未来发展

继电保护技术未来的趋势将是向着计算机化,网络化,智能化,保护,控制,调查和数据通信一体化发展。

2.1计算机化

随着计算机硬件的迅速发展,微机保护硬件也在不断地发展。原华北电力学院研制的微机线路保护硬件已经历了3个发展历程:从8个CPU结构的微机保护出版,不到5年的发展时间,多CPU结构,后者已经发展为主线,确实不能离开模块的大模块化结构,性能提高很大,得到了广泛应用。华中科技大学的发展也从8个CPU的微机保护,发展成以采取工控机核心部分为基础的32微机保护。

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南京电力自动化研究院从一开始就开发了16个CPU为基础的微机线路保护,获得大面积推广,目前也正在研究32个微机保护硬件系统。东南大学开发的微机主机设备的保护也通过了多次改进和增强。从一开始,天津大学的发展需要超过16个CPU为基础的微机线路保护,在1988年即开始研究以32位数字信号处理器(DSP)为基础的保护,控制,调查一体化微机装置,目前在珠海自动化设备公司合作开发的一种功能齐全的32个大模块,一个模块是小型机。使用32微型芯片,只专注没有精度的手段,因为精度的A/D转换分辨率的限制,超过时间16所有被接受的转化率和成本方面的困难; 32个微型芯片有很更重要的、非常高的工作频率和计算速度,高集成度非常大的寻址空间,丰富的指挥系统和许多输入插座。 CPU寄存器,数据总线,地址总线都是32位,具有内存管理功能,存储器保护功能和责任的转换功能,(缓存)和浮点数部件都集成在CPU的高速缓存。

在电力系统微机保护的要求不断提高的情况下,除了保护的基本功能,还应该有与其他大容量故障信息和数据的长期存储空间,快速的数据处理功能,强大的通信能力,保护,控制装置和调度通过网络分享整个系统的数据,信息和网络资源的能力,高阶语言编程等。这就要求微机保护装置相当于一台PC机的功能。在计算机保护发展初期,曾经设想与小型机的继电保护装置。当时因为体积大,成本高,可靠性差,这个设想是不现实的。现在,随着微机保护装置大小相似的工控机的功能,速度快,存储容量大大超过了同年的小机器,因此,提出了一套完整的工控机的机会已经成熟的继电保护,这将是其中微机保护的发展方向之一。天津大学已开发的继电保护装置,程永通微机保护装置结构完全相同不低于工控机执行,以改变人为地变成。这种设备的优点包括:具有的486PC机功能齐全,能够满足各种功能要求,这将保护当前和未来微机。规模和结构与目前的微机保护装置相似,工艺精良,具有防震,防电磁干扰能力,可移动,在非常严重的工作条件下,成本可以接受。使用的STD主线或PC 主线,硬件调制,可以选择不同的模块,对于不同的保护,配置灵活,易于扩展。

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继电保护装置,计算机化是不可逆转的发展趋势。如何,但以满足电力系统的要求,如何进一步提高继电保护的可靠性,如何获得更大的经济效益和社会效益,还必须进行专门的深入研究。

2.2网络化

计算机网络已经成为信息时代的信息和数据通信工具的技术支柱,导致了人类的生产和社会生活中出现了彻底改变。它深刻地影响每一个行业领域,每个行业领域也提供了强大的通信手段。到目前为止,除了差动保护和垂直关联保护,所有的继电器保护装置不仅可以响应保护装置的地方电力的精神。继电器的保护功能也只限于切除故障部分,减少事故的影响范围。这主要是因为缺乏强大的数据通信方式。国外已经提出系统保护的概念,这在当时主要是指安全、自动装置。因为继电器的保护功能不仅限于切除故障部分,并限制事故影响的范围(这是最重要的任务),但也必须保证整个系统的安全稳定运行。这就要求每个保护单元都能够分享到整个系统的运行和故障信息的数据,每个保护单元能够在分析这些信息和数据的基础上同步动作叠加制动齿轮,保证系统的安全稳定运行。显然,实现这种系统保护的基本条件是加入整个系统的每个主设备保护装置,是实现微机保护装置联网的计算机网络。目前的技术条件下,这是完全可能的。

对于一般的非系统保护,实现保护装置的计算机联网也有很大的优势。继电保护设备可以获取系统故障的详细信息,然后到崩溃的性质,更准确的故障位置判断和故障距离检测。通过自适应保护原理研究,经过了相当长的一段时间,终于取得了一定的成绩,但也必须认识到,真正保护系统的运行方式和故障自动适应,必须获得更多的系统运动和故障信息,只有实现保护计算机网络,才可以实现这一点。

对于某些保护装置实现计算机网络的功能,还可以提高保护的可靠性。天津大学在1993年根据在未来的三峡水电站500kV超高压多回线路母线分布式母线保护的原则之上,提出这样的看法,这种设备最终研制成功。其原理是分散传统的中央母线保护的若干(与保护母线返回方式相同)母线保护单元,分散的装在位于各回路保护屏上,每个保护单元与计算机网络相联接,每个保护单

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元只输入本回路的电流后,把它转换成的数字量,通过计算机网络传送给其它所有回路保护单元,每个保护单元根据本回路的电流和其它所有回路的电流从计算机网络获取信息,进行母线差动保护的计算,如果计算结果证明是母线内部故障,那么只跳开本回路的断路器,故障母线被隔离。当母线区域细分,每个保护单元都计算为外部故障不采取动作。这种与计算机网络相结合的分布式母线保护的原则,比传统的中央母线保护原则具有更高的可靠性,功能更加完善。因为如果保护单元接收的干扰或计算错误移动时,只能跳开返回路线中的断路器,不能导致母线整个的恶性事故而切除,根据三峡电源厂,以有“超高压母线系统中的关键地位,在功能上是极为重要的。

由上述可以知道,微机保护装置,可大大提高保护性能和可靠性,这将是微机保护发展的必然趋势。

2.3保护,控制,调查,数据通信集成一体化

在实现继电器的情况下,电脑的保护,保护装置实际上是一种高性能,多用途的电脑,在整个电力系统计算机网络的智能终端,通过网上的任何信息和数据,它就可能获得电力系统运行和故障信息数据,也可能获得任何信息和数据传输网络控制中心或无论任何终端保护的一部分。因此,每个微机保护装置不仅可完成继电保护的功能,而且在不击穿正常运行的情况下也有可能完成调查,控制,数据通信功能,能够实现保护,控制,调查显示,数据通信一体化。

目前,为了调查,保护和控制的需要,室外变电站的所有设备,如变压器,二次电压线等,所有的电流必须使用直接的控制电缆。规定了大量的控制电缆不仅需要大量投资,而且还会使二次回路更加复杂。但如果上述的保护,控制,调查,数据通信一体化在计算机上安装,将保护装置安装在室外变电站附近,由保护装置把电压,电流变为数字量后,将提供给计算机,通过网络进行传输,则可能避免大量的控制电缆。如果采用光纤传输介质的网络,也可以避免电磁干扰。现在的光电电流互感器(OTA)和光电压互感器(OTV)正在研究试验阶段,将来必然在电力系统中得到广泛的应用。在使用OTA和OTV情况时,保护装置应放在距离OTA和OTV最近的地方,那是应该在保护装置附近放置。通过OTA和OTV之后,在这个一体化装置中输入的信号,转换成电信号,一方面作为

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保护的计算判断信息数据;另一方面作为调查的数量,通过网络来提供。可以通过网络提供保护装置的操作控制命令,通过这一综合装置,进行断路器操作和判断。天津大学在1992年提出的保护,控制,调查,通信一体化问题,并已开发TMS320C25数字信号处理器(DSP)为基础的保护,控制,调查,数据通信一体化装置。

2.4 智能化

近年来,人工智能技术如神经网络,遗传算法,进化规划,模糊逻辑等等,在电力系统中的各个领域都得到了广泛应用,也开始在继电保护领域的应用进行研究。神经网络是一种非线性映射的方式,很多种复杂的带有困难方程的或很难解决的非线性问题,如果应用神经网络侧的原则,可迎刃而解。对于展品的情况,例如双方在传输线系统电势的角度发生后的过渡电阻短路是一种非线性的问题,很难判断出正确的故障位置,根据保护的原则,从而造成移动错误或拒动;如果采用神经网络的方法后,通过大量的故障样本检测,只要样本集中充分考虑各种情况,然后在休息停机时间,任何所有可能就会正确区分。其他如遗传算法,进化规划等也都具有其独特的解决复杂问题的能力。这些人工智能方法,可能会加快导致解决方案的速度。天津大学进行的神经网络型继电保护从1996年开始研究,已经取得了初步的成果。可以预测,人工智能技术,必然是能够获得在继电保护领域上的广泛应用,因为解决了用常规方法难以解决的问题。

3结论

建国以来,中国的电力系统保护技术已经历了四个阶段。随着电力系统和计算机技术,通信技术的快速发展,继电保护技术将面临着进一步发展的趋势。国内和国际上在保护技术的发展趋势将是:计算机化,网络化,保护,控制,测量,数据通信一体化和人工智能化,这不仅使得保护工作具有艰巨的任务,而且还开辟了广阔的发展空间。

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