技术
The development history, status and trends of the microcomputer protection of power plants
M Johnson
Abstract: power system protection goes through a long-term development, which has entered the microcomputer protection period of development. To this end, the brief history of the development of microcomputer protection is made to indicate the advantage which is compared with the traditional one. Highlight introduction is the new trends in microcomputer protection, namely self-accommodation controlled technology, and substations integrated automation technology applications.
Keywords: relay; microcomputer relay; automation
The rapid development of the power system relay continuing to set new requirements, electronic technology, computer technology and the rapid development of communication technologies and development of technologies for protective continuously injected new vitality. A protective relay is a device that may be energized by a voltage signal, a current signal, or both. When energized, it operates to indicate or isolate an abnormal operating condition. Basically the protective relay consists of an operating element and a set of contacts. The operating element takes the signal from sensing devices in the system, such as current or potential transformers (or both), performs a measuring operation, and responds to the results by causing the contacts to open or close. When the relay operates, it may either actuate a signal or complete a circuit to trip a circuit to trip a circuit breaker, which in turn isolates the section of the system that is in trouble.
Power system relay and the type of development experience, commutation type, transistors and integrated circuits - type stages, now developed to a stage of microcomputer protection.
That is the digital computer relay computers (including miniature machine) to constitute the basis of the relay. It originated in 20 Century 60 Years later, in the
Computer technology in the 70 early and mid-1990s there have been major breakthroughs in the rapid development of LSI technology, makes micro-processors and micro-computer into a practical stage. The dramatic decline in prices may * Xing, the dramatic increase in computational speed, to a climax computer protective research. In the late 1990s, the emergence of a relatively perfect computer protection prototype, and put into trial operation of the electricity system. 80 Age structure of computer hardware and software protection technology matures, and in some countries replication. 90 Age, the power system relay protection technology developed to computer era, it is protective of the historical process of technological development of the fourth generation.
Since the late 1970s, had started a computer research relay, institutions of higher learning and research institutes play a leading role. Thus, different principles and different types of computer cabling and the protection of their equipment for a new generation of power system provided excellent performance, functional and reliable work protective devices. With computer protection device studies in computer protection software, algorithms have also made a lot of theories.
In the realization of computerization and networking protective conditions, the protection device is actually a high-performance, multifunctional computer, the whole electrical system, a computer network wisdom terminals. It can obtain from the Internet operation and the failure of any electrical system information and data; it can also be obtained any protected information and data transmission device to the network control center or any terminals. Therefore, each computer protection devices will be completed protective functions, but in the absence of normal operations can complete breakdown measurement, control, data communications functions, namely the achievement of protection, control, surveying, and data communications integration.
Currently, in order to measure, protection and control needs, all outdoor substation equipment, such as transformers, lines, secondary voltage, and the current must be controlled from the main cables. Substantial control of the laying of cables not only massive investment, but also to secondary circuit is very complex. But if the protection, control, measurement, data communications integrated computer devices, local outdoor transformer stations installed in the adjacent protected equipment will be protected equipment voltage, the device Dianliuliang conversion of the volume figures, through computer networks to control, the control cables can be substantial. If used as a fiber network transmission medium, but also from electromagnetic interference. Now photocurrent transformer (OTA) and optical voltage transformer (OTV) in the pilot phase of the study, the electricity system in the future will be applied. OTV in the Ota and the circumstances, protection devices should be placed away from BP and OTV recent local, or to be placed on the protected equipment nearby. OTV BP and the optical signal devices, and integration of this electrical signal conversion, on the one hand, for the protection of judgment; on the other hand as a measurement volume through the network to control. From the room through the network of protected equipment will be ordered to control the operation of the integrated devices, the devices operate from the implementation of integrated devices. In 1992, experts made the protection, control, measurement, communications integration and the development of a TMS
Protective technology is the future trend to computerized, networked, intelligent, protection, control, measurement and data communications integration.
With computer protection device studies in computer protection software, algorithms have also made a lot of theories and practical applications in several parts. Research and practice show that compared with the traditional relay, computer protection has many advantages, the main features as follows:
1) Improve and enhance the functioning of protective features and performance, the correct rate movements. Will be mainly in the protection of limited access to conventional character; Its strong memory failure to achieve better weight protection; May introduce automatic control, and new technologies such as adaptive mathematics, a prediction, control and artificial neural network vague, its correct operation rate has been proven in operational practice.
2) It can easily expand other support functions. If Guzhanglubo, waveform analysis can be conveniently contained additional low frequency cut, an automatic switch on, Guzhanglubo, failures ranging function.
3) Processes structural conditions favorable. Embodied in hardware more generic, it’s easy to manufacture uniform standards; small device size, reduced disc spaces; consumption low.
4) It may easily improve. Reflected in the figures are affected by temperature changes character components, power fluctuations, the impact of life expectancy, not affected by the impact of the replacement of components; And includes a strong ability to make an inspection and available methods of detection of major software components, the status and functions of software components itself.
5) To facilitate the use of flexible, computer interface more friendly. Its more convenient to carry, thus shortening repair time; At the same time based on operational experience in the field may change the way through software identity, structure.
6) It can afar control. Computer protection devices with serial communications functions, and substations computer control system for communication with the remote control computer protection characteristics.
Protective technologies to the development trend of computerization, networking and intelligent, protection, control, measurement and data communications integrated development. With the rapid development of computer technology and computer power systems in the field of universal application relay, the new control theory and methods to be used by computer relay, with a view to achieving better results, so that computer relay to a higher level of research development, there have been some notable new trend.
Modern computer technology, communications technology and Internet technology for transformer stations to change the current surveillance, control, protection and metering devices and systems are state of the portfolio and provides the technical foundation of system integration. High, ultrahigh voltage transformer stations are facing a technological innovation. Relay and combining integrated automation became possible with its performance in the integrated resource sharing, remote control and information sharing. Modules for remote terminals (RTU), computer protection devices at the core, substations control, signals, measurements, such as circuit in a computer system before, replacing traditional control over the protection of the screen, to reduce the size substations and equipment investment, and enhance the secondary system can reasonable. As computer performance continues to improve, the rapid development of modern communication technologies, and rolled out standardized statute, transformer stations integrated automation became hot topic.
Currently, transformer stations for the surveillance, control, protection, including Guzhanglubo, emergency control devices, has been achieved digital computer, but almost all the functions of a single independent devices, each device and the lack of overall co-ordination functions fine-tune and function to enter the information can not be shared, wiring complex as a whole can be reduced sexual , at the same time can not take full advantage of powerful computer data processing functions and speed, is a waste economically. Now widely applied substation automation systems for conventional automation system, automatic control technology its applications, computer data acquisition and processing technology, communications technology, to replace manual transformer stations for the normal operation of surveillance, operation, Dianyawugong control, measurements recorded and statistical analysis, failure operation surveillance, warning and incident records and order the operation, Most do not involve protective and emergency control, Guzhanglubo, RTU, maintenance of information processing and other functions, function relatively simple.
In all, the microcomputer protection will be shown new characteristic with the progress and development of a variety of technical update features, and also will have a wider application.
Article source material:
发电厂微机继电保护发展的历史、现状及其趋势
约翰逊 M
瑞典理工大学
摘 要：电力系统继电保护经过长期发展，已经进入微机继电保护发展时期。为此，对微机继电保护的发展史作了简述，指出其与传统的继电保护相比所具有的优点。重点介绍了微机继电保护的新趋势，变电所综合自动化技术的应用。
关键词：继电保护；微机继电保护；自动化
电力系统的飞速发展对继电保护不断提出新的要求，电子技术、计算机技术与通信技术的飞速发展又为继电保护技术的发展不断地注入了新的活力。继电器是靠电压，电流或是有它们共同作用而动作的一种装置。当（线圈）励磁时，它就动作指示或切断非正常运行状态。一般来讲，继点保护器是有一个测量元件和一系列触点构成的。如同电流互感器，电压互感器工作原理一样，测量元件从系统中的互感器获得电流，进行测量，并使各个触点打开或闭合。当继电器动作时，它或发信号，或是断路器跳闸，切断系统中的故障部分。
电力系统继电保护的发展经历了机电型、整流型、晶体管型和集成电路型几个阶段后，现在发展到了微机保护阶段。
微机继电保护指的是以数字式计算机（包括微型机）为基础而构成的继电保护。它起源于20世纪60年代中后期，是在英国、澳大利亚和美国的一些学者的倡导下开始进行研究的。60年代中期，有人提出用小型计算机实现继电保护的设想，但是由于当时计算机的价格昂贵，同时也无法满足高速继电保护的技术要求，因此没有在保护方面取得实际应用，但由此开始了对计算机继电保护理论计算方法和程序结构的大量研究，为后来的继电保护发展奠定了理论基础。
计算机技术在70年代初期和中期出现了重大突破，大规模集成电路技术的飞速发展，使得微型处理器和微型计算机进入了实用阶段。价格的大幅度下降，可*性、运算速度的大幅度提高，促使计算机继电保护的研究出现了高潮。在70年代后期，出现了比较完善的微机保护样机，并投入到电力系统中试运行。80年代，微机保护在硬件结构和软件技术方面日趋成熟，并已在一些国家推广应用。90年代，电力系统继电保护技术发展到了微机保护时代，它是继电保护技术发展历史过程中的第四代。从70年代末即已开始了计算机继电保护的研究，高等院校和科研院所起着先导的作用，至此，不同原理、不同机型的微机线路和主设备保护各具特色，为电力系统提供了一批新一代性能优良、功能齐全、工作可靠的继电保护装置。随着微机保护装置的研究，在微机保护软件、算法等方面也取得了很多理论成果。
在实现继电保护的计算机化和网络化的条件下，保护装置实际上就是一台高性能、多功能的计算机，是整个电力系统计算机网络上的一个智能终端。它可从网上获取电力系统运行和故障的任何信息和数据，也可将它所获得的被保护元件的任何信息和数据传送给网络控制中心或任一终端。因此，每个微机保护装置不但可完成继电保护功能，而且在无故障正常运行情况下还可完成测量、控制、数据通信功能，亦即实现保护、控制、测量、数据通信一体化。
目前，为了测量、保护和控制的需要，室外变电站的所有设备，如变压器、线路等的二次电压、电流都必须用控制电缆引到主控室。所敷设的大量控制电缆不但要大量投资，而且使二次回路非常复杂。但是如果将上述的保护、控制、测量、数据通信一体化的计算机装置，就地安装在室外变电站的被保护设备旁，将被保护设备的电压、电流量在此装置内转换成数字量后，通过计算机网络送到主控室，则可免除大量的控制电缆。如果用光纤作为网络的传输介质，还可免除电磁干扰。现在光电流互感器(OTA)和光电压互感器(OTV)已在研究试验阶段，将来必然在电力系统中得到应用。在采用OTA和OTV的情况下，保护装置应放在距OTA和OTV最近的地方，亦即应放在被保护设备附近。OTA和OTV的光信号输入到此一体化装置中并转换成电信号后，一方面用作保护的计算判断；另一方面作为测量量，通过网络送到主控室。从主控室通过网络可将对被保护设备的操作控制命令送到此一体化装置，由此一体化装置执行断路器的操作。1992年,专家提出了保护、控制、测量、通信一体化问题，并研制了以TMS
随着微机保护装置的研究，在微机保护软件、算法等方面也取得了很多理论成果，并且应用于实际之中。研究和实践证明，与传统的继电保护相比较，微机保护有许多优点，其主要特点如下：
1)改善和提高继电保护的动作特征和性能，动作正确率高。主要表现在能得到常规保护不易获得的特性；其很强的记忆力能更好地实现故障分量保护；可引进自动控制、新的数学理论和技术如自适应、状态预测、模糊控制及人工神经网络等，其运行正确率很高也已在运行实践中得到证明。
2)可以方便地扩充其他辅助功能。如故障录波、波形分析等，可以方便地附加低频减载、自动重合闸、故障录波、故障测距等功能。
3)工艺结构条件优越。体现在硬件比较通用，制造容易统一标准；装置体积小，减少了盘位数量；功耗低。
4)可靠性容易提高。体现在数字元件的特性不易受温度变化、电源波动、使用年限的影响，不易受元件更换的影响；且自检和巡检能力强，可用软件方法检测主要元件、部件的工况以及功能软件本身。
5)使用灵活方便，人机界面越来越友好。其维护调试也更方便，从而缩短维修时间；同时依据运行经验，在现场可通过软件方法改变特性、结构。
6)可以进行远方监控。微机保护装置具有串行通信功能，与变电所微机监控系统的通信联络使微机保护具有远方监控特性。
继电保护技术发展趋势向计算机化，网络化，智能化，保护、控制、测量和数据通信一体化发展。随着计算机技术的飞速发展及计算机在电力系统继电保护领域中的普遍应用，新的控制原理和方法被不断应用于计算机继电保护中，以期取得更好的效果，从而使微机继电保护的研究向更高的层次发展，出现了一些引人注目的新趋势。
现代计算机技术、通信技术和网络技术为改变变电站目前监视、控制、保护和计量装置及系统分割的状态提供了优化组合和系统集成的技术基础。高压、超高压变电站正面临着一场技术创新。继电保护和综合自动化的紧密结合已成为可能，它表现在集成与资源共享、远方控制与信息共享。以远方终端单元（RTU）、微机保护装置为核心，将变电所的控制、信号、测量、计费等回路纳入计算机系统，取代传统的控制保护屏，能够降低变电所的占地面积和设备投资，提高二次系统的可*性。随着微机性能价格比的不断提高，现代通信技术的迅速发展，以及标准化规约的陆续推出，变电站综合自动化成了热门话题。
目前，用于变电站的监视、控制、保护，包括故障录波、紧急控制装置，虽然已实现了微机数字化，但几乎都是功能单一的独立装置，各个装置缺乏整体协调和功能的调优，且功能孤立，输入信息不能共享，接线复杂，从整体上降低了可靠性，同时不能充分利用微机数据处理的强大功能和速度，经济上也是一种浪费。现在广泛应用的变电站自动化系统为常规自动化系统，它应用自动控制技术、计算机数据采集和处理技术、通信技术，代替人工对变电站进行正常运行的监视、操作、电压无功控制、量测记录和统计分析、故障运行的监视、报警和事件顺序记录与运行操作，大多不涉及继电保护、紧急控制、故障录波、RTU、维修状态信息处理等功能，功能相对比较简单。
竞争的电力市场将促进新的自动化技术的开发和应用，在经济效益的驱动下，变电站将向集成自动化方向发展。根据变电站自动化集成的程度，可将未来的自动化系统分为协调型自动化和集成型自动化。协调型自动化仍然保留间隔内各自独立的控制、保护等装置，各自采集数据并执行相应的输出功能，通过统一的通信网络与站级相连，在站级建立一个统一的计算机系统，进行各个功能的协调。而集成型自动化既在间隔级，又在站级对各个功能进行优化组合，是现代控制技术、计算机技术和通信技术在变电站自动化系统的综合应用。所谓集成型自动化系统是将间隔的控制、保护、故障录波、事件记录和运行支持系统的数据处理等功能集成在一个统一的多功能数字装置内，间隔内部和间隔间以及间隔同站级间的通信用少量的光纤总线实现，取消传统的硬线连接。
总之，微机保护必将随着各种技术的进步和发展呈现更新的特征，也将获得更广泛的应用。
文章来源：瑞典理工大学、电子和计算机工程学校，技术报告第393l、2001.
