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1、<p><b>  英文翻譯(譯文)</b></p><p>  英 文 名 稱(chēng)Application guide for the choice of protective relays </p><p>  中 文 名 稱(chēng) 繼電保護(hù)選擇的應(yīng)用指導(dǎo)

2、 </p><p>  學(xué) 生 姓 名 </p><p>  學(xué) 號(hào) </p><p>  系、年級(jí)專(zhuān)業(yè) 電氣工程系、10電氣工程及其自動(dòng)化 </p><p>  指 導(dǎo) 教 師

3、 </p><p>  職 稱(chēng) </p><p>  2014年 1 月 20 日</p><p>  Application guide for the choice of protective relays</p><

4、p>  1. INTRODUCTION </p><p>  Protective Relays are the brain of the electrical apparatus. In this respect, their choice is a critical step in the The selection of protective devices is based on: </p&

5、gt;<p>  The safety of personnel and equipment (sensitivity of detection and response time). </p><p>  The quality and continuity of the electrical supply (fault determination, special directional pro

6、tection, automatic transfer and fast clearing times to improve/ensure system stability).</p><p>  The optimization of the power system’s reliability and safety dictates the use of independent stand-alone rel

7、ays located close to the power circuit breakers that they control. In some cases, improvements in the overall protection performance are possible by transmitting the relay status to a remote location (known as important

8、to ensure that these additional functions do not jeopardise the inherent integrity </p><p>  In recent years, technological progress has led to the use of microprocessors in protective relay manufacture. Thi

9、s has led to: </p><p>  A significant increase in the amount of information that is processed by the relays. </p><p>  Easy calculation of electrical quantities such as harmonics. </p>&l

10、t;p>  Secure and reliable exchange of digital information with remote locations.</p><p>  Continuous monitoring of protection relay integrity by self-supervision and auto-diagnostics.</p><p>

11、  CEE have developed the PROCOM range of digital protection relays, which benefits from the above advantages without sacrificing the stand-alone capability of the classical solid state relays such as the ITG and TTG seri

12、es. </p><p>  In addition to the PROCOM protection relays such as the RMS, RMSD, RMSR, IMM, GMS and DMS relays, the PROCOM range also includes the CMS digital instrumentation units, AMS local PLCs and PMG.&l

13、t;/p><p>  It is therefore possible, by selecting the appropriate combination of units, to define a complete circuit breaker local management system including Protection, Automation and Instrumentation. </p&

14、gt;<p>  Nowadays, the difficult economic environment within the industry is imposing increasing demands on efficiency by reducing operating and maintenance costs. At the same time, improvements are required in th

15、e continuity and quality of supply, together with personnel and equipment safety. </p><p>  With these trends in mind, CEE has recently developed the PROSATIN range of equipment, which combines the capabilit

16、ies of the PROCOM range with that of the MicroSATIN range to provide the complete Integrated Protection, Supervision and Remote Control of Electrical Power Networks. </p><p>  The PROSATIN systems therefore

17、provide full SCADA function for Electrical Power Networks, combining the following functions: </p><p>  Protection </p><p>  Supervision (Measurements, Alarms, Data Logging and Mimic Diagrams) &

18、lt;/p><p>  Control (Local or remote by VDU) </p><p>  PROSATIN reduces costs and improves continuity of supply by: </p><p>  Reducing the time to check and analyse the power system op

19、erational status of parameters, </p><p>  Increasing preventative maintenance by automatic and continuous supervision including auto-diagnosis,</p><p>  Optimisation of energy costs, and </p&

20、gt;<p>  Improvements in operational procedures and maintenance leading to reduced downtimes.</p><p>  In order to be adaptable to varying degrees of user needs, PROSATIN is available in the following

21、 sub-systems:</p><p>  PS1000: Simple supervisory systems based on desktop PCs intended for use in relatively small electrical networks. </p><p>  PS2000: SCADA system with time logging for indu

22、strial plants and distribution networks. </p><p>  PS4000: Complete high-speed SCADA system for industrial plants. </p><p>  The selection of protection relays therefore depends upon the answer

23、to two basic questions:</p><p>  a) What are the local protective functions necessary to give the best conditions for the Power System Safety and fault discrimination? </p><p>  b) Will the powe

24、r system be supervised or controlled in the future? </p><p>  The answer to the second question determines the type choose the classical solid state protection, or the more modern microprocessor controlled d

25、igital relays. </p><p>  The answer to the first question determines the selection of protective relay types and their setting ranges. This, together with the power system behaviour (under both steady state

26、and transient conditions) is the subject of this guide. </p><p>  Note that the PROSATIN modular architecture enables a gradual step-by-step implementation of a full supervisory system. The PROCOM protection

27、 range can be easily integrated into an existing installation while the measuring units, the local PLCs and the data loggers are installed in stages, taking into account the existing system.</p><p>  2. HIG

28、H VOLTAGE INDUSTRIAL & DISTRIBUTION NETWORKS</p><p>  Protective relays play an important role in the operation of industrial networks. If they are correctly applied they provide protection of both equip

29、ment and personnel together and ensure the best possible quality of electrical power supply. </p><p>  The object of this guide is to define the protective relays that are the most suited to the layout of th

30、e electrical power system network (parallel operation of production units or step-down substations, ring-main or radial distribution, type of network earthing, etc.). </p><p>  Reference is made to various t

31、ypes of overcurrent relays: </p><p>  ITG, RMS and RMSA series.</p><p>  ITG relays are classical solid state overcurrent and earth fault relays. RMS and RMSA relays are microprocessor based rel

32、ays which use an original method of analysing input current signals; the Fast Fourier Transformation. Using this feature a large number of harmonics are taken into account to build currents with a true RMS value. This pe

33、rmits relays to be desensitised to certain harmonics for special applications. Furthermore relays of the RMSA series are autonomous in that they can operate wi</p><p>  2.1 PROTECTION AGAINST PHASE TO PHASE

34、 FAULTS </p><p>  Overcurrent protection is the basic protection used in electrical power networks. They must be both sensitive and rapid in order to minimise the stress imposed on the equipment during the f

35、ault period (electrodynamic and thermal stresses). </p><p>  It is also essential that they should be selective, that is capable of eliminating only the faulty element whilst maintaining the supply to health

36、y parts of the network. </p><p>  2.1.1 Choice of the time/current characteristic </p><p>  Overcurrent protection relays are mainly characterised by their time/current characteristic. Several

37、types are available: </p><p>  Independent or definite time relays (whose operating time is independent of current level) </p><p>  Dependent or inverse time relays (whose operating time depends

38、 on the current level). </p><p>  This last type of relay may be sub-divided into three categories according to the IEC standard 255-4: </p><p>  Inverse time relays (ITG7200 se

39、ries )</p><p>  Very inverse time relays (ITG7300 series )</p><p>  Extremely inverse time relays (ITG7400 series )</p><p>  Digital multi-curve overcurrent re

40、lay (RMS700, RMS7000, RMST7000 and RMSA7000 series) </p><p>  No particular criterion exists for the systematic choice of one or other type of relay. However, dependent time relaying is preferable in the f

41、ollowing cases where: </p><p>  The operation of the network includes high-level short-time overloads, </p><p>  Magnetising inrush currents at switch-on may be considerable for several tenths o

42、f a second, </p><p>  Relay operation must be co-ordinated with a large number of fuses. </p><p>  On the other hand, independent time relays are preferable when the short-circuit level is very

43、high, or when it is likely to vary widely at a given point (for example when a network is supplied from small generators whose short-circuit decrement curve falls off rapidly). </p><p>  As a basic rule, how

44、ever, there is a general tendency to use independent time relays in Continental Europe and dependent time in Anglo-Saxon countries. </p><p>  Time-delayed overcurrent relays lend themselves to chronological

45、selectivity. This however is not without a certain inconvenience, in that fault clearance time increases closest to the source, where short-circuit levels are the highest. It is thus necessary to minimise the grading int

46、erval . </p><p>  The grading interval normally used for electronic protection relays is 400 ms, which is obtained by summating the following: </p><p>  Breaker fault clearance time, </p>

47、<p>  Summation of the time errors of the two relays, </p><p>  Overshoot of the upstream relay, </p><p>  Safety margin of approximately 100 ms. </p><p>  When transformer fe

48、eder protection is being considered it is advisable to use relays having an instantaneous high-set unit. This is set above the secondary short-circuit level and transformer in-rush current, which then allows the operatin

49、g time of upstream relays to be reduced thereby reducing the cable short-circuit withstand requirements. </p><p>  The grading interval may be reduced if required, for times less than about 1 sec, to 250 ms,

50、 using relays with high-stability timer circuits (which is the case with ITG 7000 or RMS 700/7000 relays). </p><p>  2.1.2 Accelerated selective protection </p><p>  In cases where the number o

51、f grading steps at one voltage level would lead to fault clearance times which are either too long for the withstand of the equipment in the network, or incompatible with the time allowed by the power distribution author

52、ity, it is possible to use an accelerated system.</p><p>  This consists of reducing the relay time-delay to a pre-determined minimum value when the fault is on the section immediately downstream. The inform

53、ation required to achieve this is transmitted from the downstream relay to the upstream relay via wiring. The fault clearance time is thus independent of its location, the relay minimum operating time being a function on

54、ly of the speed with which the downstream information can be transmitted (the operating time of the “instantaneous” unit of the down</p><p>  Relay types ITG 7172 and ITG 7173 (and RMSR relays) with a two-le

55、vel definite time characteristic for phase faults and a single level for earth faults operate in accordance with this principle. The phase fault high-set unit and the earth-fault unit are associated with the acceleration

56、 logic incorporated inside the relay, the low-set unit being used to protect against overloads and is totally independent of the logic. In order to maintain a high degree of security, selective (or graded) back-up t</

57、p><p>  2.1.3 Differential protection</p><p>  This type of protection operates on the principle of current comparison in the same phase but at the two extremities of the protected equipment, (cab

58、le: SOLKOR-RF, transformer: DMS7002, DTT7031, rotating machines: DMS 7001, DTM 7033, IAG 7034 or bus bars: IAG 7034) and has two main advantages:</p><p>  It may be instantaneous, because it only reacts to f

59、aults inside the protected zone, </p><p>  It will operate for the transfer of energy in either direction, which is particularly important in the event of multiple sources. </p><p>  It may also

60、 allow a grading step to be eliminated, thus reducing the tripping time for faults on the upstream network. To counterbalance these advantages however, it requires pilot links (SOLKOR-RF) and matched class X current tran

61、sformers are generally recommended with stabilising resistors for the differential protection of transformers, rotating machines and busbars. </p><p>  The differential relays for cable protection, type SOLK

62、OR-RF, operate on a special principle </p><p>  They do not compare individually the currents in each phase, but rather a combination of the three currents. </p><p>  The advantage of this syste

63、m is that only one pair of pilot wires is required, but the operating levels are different for faults on different phases. </p><p>  2.1.4 Directional protection</p><p>  When a substation is s

64、upplied by two cables or two transformers in parallel, the protection on these two feeders (in the upstream substation) would operate simultaneously for a fault affecting one of them. To obtain selective protection it is

65、 necessary to use either differential or directional relays. In the latter case phase directional overcurrent relays type RMSD7921 or ITD7111 should be installed on each incomer. </p><p>  The directional el

66、ement of these relays checks the phase angle between the current and voltage of one phase, and allows the overcurrent unit to operate if this phase angle indicates current in the reverse direction. </p><p> 

67、 RMSD 7000 relays, with the FFT input signal treatment, check the phase angle between the fundamental of current and voltage. As a result they remain stable and selective even in networks containing high levels of harmon

68、ics.</p><p>  The time delay of the directional relay is chosen to be selective with the upstream relays, and thus the loop is first opened (by tripping the correct LV breaker), followed by the upstream prot

69、ection isolating the faulty feeder. Alternatively, the upstream breaker may be opened by sending an intertrip signal from the LV directional relay to accelerate fault elimination. </p><p><b>  1 簡(jiǎn)介<

70、/b></p><p>  繼電保護(hù)裝置可以認(rèn)為是電力系統(tǒng)設(shè)備裝置中的大腦部分。在這一方面,他們的選擇是電力系統(tǒng)的設(shè)計(jì)和發(fā)展不可缺少的一步。</p><p>  保護(hù)設(shè)備的選擇是基于以下幾點(diǎn)原則:</p><p>  保證供電能供應(yīng)的質(zhì)量和連續(xù)性(短路判斷、特別是方向保護(hù),自動(dòng)傳輸和快速清除時(shí)間的提高/保障系統(tǒng)的穩(wěn)定性)</p><p>

71、;  保護(hù)人員和設(shè)備的安全(能夠敏感的察覺(jué)到變化,并有所反應(yīng))。</p><p>  為了使電力系統(tǒng)的穩(wěn)定性和安全性達(dá)到最優(yōu)化的需求,規(guī)定我們?cè)诳拷娏€路斷路器側(cè)配置使用獨(dú)立的繼電器來(lái)控制。在一些特殊情況下,通過(guò)信號(hào)的傳輸終端或自動(dòng)單元來(lái)做來(lái)提高所有保護(hù)設(shè)備的性能也成為可能。然而,在使用這些的時(shí)候我們需要保證外加的功能不能夠?qū)Ρ镜氐睦^電保護(hù)產(chǎn)生威脅。</p><p>  最近幾年,隨著微

72、控制器在繼電保護(hù)上的應(yīng)用和發(fā)展,繼電保護(hù)呈現(xiàn)出以下趨勢(shì):</p><p>  繼電器能夠處理更多有用的數(shù)據(jù)</p><p>  電量和諧波的計(jì)算的計(jì)算越來(lái)越簡(jiǎn)單</p><p>  與遠(yuǎn)方終端的數(shù)字信息交換的安全和可靠性提高</p><p>  通過(guò)自身監(jiān)控和自動(dòng)故障保護(hù)的智能功能對(duì)繼電保護(hù)裝置進(jìn)行不斷的監(jiān)控掃描。</p>&l

73、t;p>  歐洲各國(guó)發(fā)展基于PROCOM技術(shù)的數(shù)字繼電器,在不犧牲古典固態(tài)繼電器的獨(dú)立能力如ITG和TTG系列繼電器的基礎(chǔ)上提高它的性能。</p><p>  另外,基于PROCOM技術(shù)的保護(hù)繼電器如RMS,RMSD,RMSR,IMM,GMS 和DMS繼電器,也包括CMS的數(shù)字儀表單元,AMS本地可編程邏輯控件等,所有的這些設(shè)計(jì)基于數(shù)字化設(shè)計(jì)都是為了滿(mǎn)足歐洲各國(guó)繼電保護(hù)設(shè)備應(yīng)用標(biāo)準(zhǔn)的要求。</p>

74、;<p>  因此通過(guò)選擇適當(dāng)單元的組合來(lái)實(shí)現(xiàn)完整的電流斷路器的本地管理系統(tǒng),更好地實(shí)現(xiàn)繼電保護(hù)系統(tǒng)的完善性,包括保護(hù)、自動(dòng)化和結(jié)構(gòu)化將成為可能。</p><p>  現(xiàn)今,在經(jīng)濟(jì)環(huán)境較為困難的背景下,通過(guò)減少運(yùn)營(yíng)和維護(hù)費(fèi)用來(lái)實(shí)現(xiàn)效率的增長(zhǎng)。同時(shí),對(duì)器件的穩(wěn)定性和安全的性的要求也在不斷的提高。</p><p>  考慮到這些趨勢(shì)和要求,歐洲各國(guó)最近在致力于基于PROSATIN

75、范圍內(nèi)的器件的研究,它是由許多PROCOM組成的微型智能控制保護(hù)系統(tǒng)。能夠?qū)﹄娏W(wǎng)絡(luò)實(shí)行遠(yuǎn)方終端控制制系統(tǒng)的監(jiān)管。</p><p>  PROSATIN系統(tǒng)因此為電力系統(tǒng)網(wǎng)絡(luò)提供了全數(shù)據(jù)采集功能,主要功能有以下幾個(gè)部分組成:</p><p><b>  保護(hù)功能</b></p><p>  監(jiān)管功能(測(cè)量、預(yù)警、數(shù)據(jù)邏輯和圖表模擬等)</

76、p><p><b>  控制功能</b></p><p>  PROSATIN通過(guò)以下支持來(lái)實(shí)現(xiàn)降低成本和提高供電可靠性:</p><p>  減少檢測(cè)時(shí)間和運(yùn)行模型參數(shù)的分析</p><p>  通過(guò)連續(xù)的自動(dòng)的監(jiān)控系統(tǒng)包括自我診斷來(lái)增加設(shè)備的自動(dòng)維護(hù)</p><p><b>  優(yōu)化能源

77、損耗</b></p><p>  提高運(yùn)行過(guò)程的性能并且減少設(shè)備維護(hù)時(shí)間</p><p>  為了滿(mǎn)足廣大使用者的需求,PROSATIN系統(tǒng)還能有以下的輔助系統(tǒng):</p><p>  PS1000:基于計(jì)算機(jī)界面的簡(jiǎn)單監(jiān)控畫(huà)面讓界面操作更為簡(jiǎn)單</p><p>  PS2000:隨生產(chǎn)計(jì)劃和網(wǎng)絡(luò)分配按時(shí)間采集數(shù)據(jù)的數(shù)據(jù)采集系統(tǒng)&l

78、t;/p><p>  PS4000:為生產(chǎn)計(jì)劃而服務(wù)的高速數(shù)據(jù)采集系統(tǒng)</p><p>  因此繼電保護(hù)部分主要有以下兩個(gè)問(wèn)題來(lái)決定:</p><p>  (a)本地繼電保護(hù)系統(tǒng)需要配置什么樣的功能才能更好的判斷電力系統(tǒng)的正常和非正常運(yùn)行?</p><p> ?。╞)在未來(lái),電力系統(tǒng)是否能夠自行監(jiān)管和控制呢?</p><p&g

79、t;  對(duì)第二個(gè)問(wèn)題的答案決定了繼電保護(hù)類(lèi)型的設(shè)計(jì)-是更多的使用傳統(tǒng)的固態(tài)模型繼電保護(hù)設(shè)備,還是更多的引進(jìn)數(shù)字微控制器模型來(lái)實(shí)現(xiàn)保護(hù)系統(tǒng)。</p><p>  對(duì)第一個(gè)問(wèn)題的答案則決定了保護(hù)類(lèi)型的選擇和他們的保護(hù)范圍的設(shè)定。綜合考慮電力系統(tǒng)行為模型(在穩(wěn)定的傳輸狀態(tài)下)是本指導(dǎo)叢書(shū)的主要探討內(nèi)容。</p><p>  注意,PROSATIN系統(tǒng)的結(jié)構(gòu)是可以通過(guò)監(jiān)控系統(tǒng)一步一步的實(shí)現(xiàn)的。PR

80、OCOM的保護(hù)范圍也是很容易安裝在已存在的測(cè)量單元上的,比如本地的PLC設(shè)備上。</p><p>  2 高電壓工業(yè)和配電網(wǎng)絡(luò)的保護(hù)</p><p>  繼電保護(hù)在電能網(wǎng)絡(luò)中扮演這非常重要的角色,他們是否能夠?qū)ζ骷腿w設(shè)備作出正確的保護(hù)動(dòng)作,這為能否提供高質(zhì)量電能提供了保證。</p><p>  這本指導(dǎo)叢書(shū)主要是定義了在電力系統(tǒng)網(wǎng)絡(luò)中繼電保護(hù)合理布局等問(wèn)題<

81、;/p><p>  它們由不同類(lèi)型的過(guò)電流繼電器組成,如:IGT,RMS和RMSA等。</p><p>  ITG繼電器是一種典型的固態(tài)過(guò)電流模型和接地短路繼電器。</p><p>  RMS和RMSA繼電器是基于微處理器的繼電器,是使用原始的方法分析輸入電流信號(hào),以及快速傅里葉變換。使用這種繼電器時(shí)需要考慮大量諧波電流的有效值。這使得這種繼電器能夠被用于一些特殊的應(yīng)用

82、中。此外繼電器RMSA系列是自控的,他們可以在沒(méi)有輔助系統(tǒng)支持的情況下通過(guò)CTs來(lái)獲得能源的支持。</p><p>  2.1 相間短路保護(hù)分析</p><p>  過(guò)電流保護(hù)是電力系統(tǒng)網(wǎng)絡(luò)中使用最基本的保護(hù)之一。他們必須要能夠快速的感知在短路情況下產(chǎn)生的電流沖擊變化量并在短時(shí)間內(nèi)做出正確的反應(yīng)(還要考慮到電應(yīng)力和熱應(yīng)力的承受范圍)</p><p>  它的另一個(gè)基

83、礎(chǔ)特性就是選擇性,能夠正確反應(yīng)故障處短路以維持供電網(wǎng)絡(luò)的健康穩(wěn)定。</p><p>  2.1.1 時(shí)間/電流特性選擇</p><p>  過(guò)電流保護(hù)繼電器的主要特征是通過(guò)他們的短路時(shí)間和短路電流特性來(lái)表征的,以下有幾種類(lèi)型選擇方案:</p><p>  獨(dú)立或明確的時(shí)間繼電器(他們的工作電流是獨(dú)立于電流等級(jí)的)</p><p>  關(guān)聯(lián)或相

84、反限時(shí)繼電器(他們的工作電流是由電壓等級(jí)來(lái)決定的)</p><p>  根據(jù)IEC 255-4標(biāo)準(zhǔn),最后一種類(lèi)型的繼電器還可以細(xì)分為三種類(lèi)型:</p><p>  反限時(shí)繼電器 (ITG7200系列)</p><p>  強(qiáng)反限時(shí)繼電器 (IGT7300系列)</p><p>  超強(qiáng)反限時(shí)繼電器 (IGT

85、7400系列)</p><p>  數(shù)字多重過(guò)電流繼電器 (RMS700,RMS7000,RMST700和RMSA7000系列)</p><p>  沒(méi)有具體的說(shuō)明規(guī)范用以來(lái)對(duì)系統(tǒng)的一個(gè)或多個(gè)類(lèi)型的繼電器的選擇。然而,時(shí)間繼電器可以用于以下幾種情況下使用:</p><p>  電能網(wǎng)絡(luò)中含有高電壓等級(jí)和短時(shí)間的過(guò)負(fù)荷現(xiàn)象</p><p>  

86、存在啟動(dòng)瞬間電機(jī)的啟動(dòng)勵(lì)磁電流侵入電網(wǎng)中</p><p>  繼電器操作必須與大量的保險(xiǎn)裝備協(xié)調(diào)融合工作時(shí)</p><p>  另一方面,獨(dú)立時(shí)間繼電器在短路電流非常高的情況下,或者在給定的點(diǎn)可能相位差很大的情況下(例如當(dāng)網(wǎng)絡(luò)提供從小型發(fā)電機(jī)的短路衰減曲線迅速脫落)它的優(yōu)勢(shì)比較大</p><p>  然而,有趣的是,在歐洲大陸一些國(guó)家則傾向于使用獨(dú)立時(shí)間繼電器,而對(duì)

87、于盎格魯-撒克遜等一些國(guó)家則傾向于使用非獨(dú)立時(shí)間繼電器。</p><p>  時(shí)滯過(guò)電流繼電器本身就具有時(shí)間選擇性。但是,這還是有一些不足之處,如最靠近電源處故障清除時(shí)間會(huì)增加,且短路電路電流非常的大。因此有必要減少分級(jí)間隔來(lái)解決這一問(wèn)題。</p><p>  電力保護(hù)繼電器中的分級(jí)間隔通時(shí)間通產(chǎn)是400 ms,由以下因素綜合考慮獲得:</p><p><b&

88、gt;  斷路故障的清除時(shí)間</b></p><p>  兩繼電器誤動(dòng)作的總時(shí)間</p><p><b>  上級(jí)保護(hù)的過(guò)操作</b></p><p>  大約為100ms的安全空余時(shí)間</p><p>  當(dāng)變壓器饋線保護(hù)被認(rèn)為是使用繼電器有一個(gè)瞬時(shí)高置單元的明智選擇。這是設(shè)置高于二次短路水平和變壓器脈動(dòng)電

89、流,然后允許將上游的操作時(shí)間繼電器減少?gòu)亩鴾p少電纜短路承受需求。</p><p>  分級(jí)間隔可能會(huì)減少如果需要,時(shí)間小于1秒,使用繼電器與高穩(wěn)定性定時(shí)器電路則在250ms左右(ITG 7000或均方根700/7000繼電器)。</p><p>  2.1.2 限時(shí)電流速斷</p><p>  在某些情況下,如分級(jí)數(shù)量在一個(gè)電壓水平下太多將導(dǎo)致故障清除時(shí)間要么是太長(zhǎng)

90、,使網(wǎng)絡(luò)和設(shè)備不能承受,或不符合配電部門(mén)允許的時(shí)候,可以使用一個(gè)加速系統(tǒng)。</p><p>  它是由。實(shí)現(xiàn)這一傳播所需的信息從下游繼電器到上游通過(guò)線路傳遞。故障清除時(shí)間是獨(dú)立于它的位置,繼電器最低操作時(shí)間僅作為一個(gè)與下級(jí)信息傳送速度有關(guān)的一個(gè)函數(shù)。</p><p>  繼電器類(lèi)型ITG 7172和IGT 7173 (包括RMSR繼電器)兩相短路故障特征和單相接地故障的時(shí)間特性原理是符合這

91、一原則。相間故障單元和接地故障單元是與加速度邏輯整合內(nèi)部繼電器相關(guān)聯(lián),低設(shè)定單元被用來(lái)防止過(guò)載和完全獨(dú)立的邏輯。因此在故障發(fā)生在沒(méi)有繼電器保護(hù)鏈接的情況下也能保證系統(tǒng)的安全性和選擇性。</p><p>  2.1.3 差動(dòng)保護(hù)</p><p>  這一保護(hù)的原則是比較同一相上電流的大小,單由兩個(gè)繼電保護(hù)裝置來(lái)執(zhí)行保護(hù)。它的優(yōu)點(diǎn)主要有以下幾個(gè):</p><p>  瞬

92、時(shí)動(dòng)作,因?yàn)樗粚?duì)故障內(nèi)部做出反應(yīng)</p><p>  它能夠識(shí)別電能的方向傳輸,特別是在多電源的情況下</p><p>  它也可能允許消除分級(jí),從而減少故障時(shí)上游網(wǎng)絡(luò)跳閘時(shí)間。然而為了平衡這些優(yōu)點(diǎn),它需要飛行員鏈接(SOLKOR-RF)和匹配類(lèi)X與穩(wěn)定電阻電流互感器通常推薦變壓器的差動(dòng)保護(hù),旋轉(zhuǎn)機(jī)器和匯流。</p><p>  電纜的差動(dòng)繼電器保護(hù),SOLKOR

93、-RF類(lèi)型,操作一個(gè)特殊原則:</p><p>  他們不單獨(dú)比較每個(gè)階段的電流,而是三個(gè)電流的結(jié)合</p><p>  這種系統(tǒng)的優(yōu)點(diǎn)是,只有一跟通信電纜是必需的,但不同相間的故障對(duì)其操作也是不同的</p><p>  2.1.4 方向保護(hù)</p><p>  當(dāng)變電所需要支持兩個(gè)電纜或是兩組平行變壓器的時(shí)候,保護(hù)系統(tǒng)會(huì)保護(hù)這兩個(gè)被保護(hù)系統(tǒng)

94、(上游變電站)同時(shí)運(yùn)行故障其中之一。獲得選擇性保護(hù)很有必要利用微分或方向繼電器。在后一種情況下階段方向過(guò)電流繼電器類(lèi)型RMSD7921或ITD7111應(yīng)安裝在每個(gè)新來(lái)者。</p><p>  這些繼電器的定向元素檢查電流和電壓之間的相位角的階段,并允許過(guò)流單元操作如果這相角顯示當(dāng)前在相反的方向。</p><p>  顯示7000年繼電器、輸入信號(hào)的FFT處理,檢查電流和電壓的相角之間的根本

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