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1、<p><b> 英文翻譯(譯文)</b></p><p> 英 文 名 稱Application guide for the choice of protective relays </p><p> 中 文 名 稱 繼電保護選擇的應用指導
2、 </p><p> 學 生 姓 名 </p><p> 學 號 </p><p> 系、年級專業(yè) 電氣工程系、10電氣工程及其自動化 </p><p> 指 導 教 師
3、 </p><p> 職 稱 </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 簡介<
70、/b></p><p> 繼電保護裝置可以認為是電力系統(tǒng)設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)的設計和發(fā)展不可缺少的一步。</p><p> 保護設備的選擇是基于以下幾點原則:</p><p> 保證供電能供應的質量和連續(xù)性(短路判斷、特別是方向保護,自動傳輸和快速清除時間的提高/保障系統(tǒng)的穩(wěn)定性)</p><p>
71、; 保護人員和設備的安全(能夠敏感的察覺到變化,并有所反應)。</p><p> 為了使電力系統(tǒng)的穩(wěn)定性和安全性達到最優(yōu)化的需求,規(guī)定我們在靠近電力線路斷路器側配置使用獨立的繼電器來控制。在一些特殊情況下,通過信號的傳輸終端或自動單元來做來提高所有保護設備的性能也成為可能。然而,在使用這些的時候我們需要保證外加的功能不能夠對本地的繼電保護產生威脅。</p><p> 最近幾年,隨著微
72、控制器在繼電保護上的應用和發(fā)展,繼電保護呈現(xiàn)出以下趨勢:</p><p> 繼電器能夠處理更多有用的數(shù)據(jù)</p><p> 電量和諧波的計算的計算越來越簡單</p><p> 與遠方終端的數(shù)字信息交換的安全和可靠性提高</p><p> 通過自身監(jiān)控和自動故障保護的智能功能對繼電保護裝置進行不斷的監(jiān)控掃描。</p>&l
73、t;p> 歐洲各國發(fā)展基于PROCOM技術的數(shù)字繼電器,在不犧牲古典固態(tài)繼電器的獨立能力如ITG和TTG系列繼電器的基礎上提高它的性能。</p><p> 另外,基于PROCOM技術的保護繼電器如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,所有的這些設計基于數(shù)字化設計都是為了滿足歐洲各國繼電保護設備應用標準的要求。</p>
74、;<p> 因此通過選擇適當單元的組合來實現(xiàn)完整的電流斷路器的本地管理系統(tǒng),更好地實現(xiàn)繼電保護系統(tǒng)的完善性,包括保護、自動化和結構化將成為可能。</p><p> 現(xiàn)今,在經濟環(huán)境較為困難的背景下,通過減少運營和維護費用來實現(xiàn)效率的增長。同時,對器件的穩(wěn)定性和安全的性的要求也在不斷的提高。</p><p> 考慮到這些趨勢和要求,歐洲各國最近在致力于基于PROSATIN
75、范圍內的器件的研究,它是由許多PROCOM組成的微型智能控制保護系統(tǒng)。能夠對電力網(wǎng)絡實行遠方終端控制制系統(tǒng)的監(jiān)管。</p><p> PROSATIN系統(tǒng)因此為電力系統(tǒng)網(wǎng)絡提供了全數(shù)據(jù)采集功能,主要功能有以下幾個部分組成:</p><p><b> 保護功能</b></p><p> 監(jiān)管功能(測量、預警、數(shù)據(jù)邏輯和圖表模擬等)</
76、p><p><b> 控制功能</b></p><p> PROSATIN通過以下支持來實現(xiàn)降低成本和提高供電可靠性:</p><p> 減少檢測時間和運行模型參數(shù)的分析</p><p> 通過連續(xù)的自動的監(jiān)控系統(tǒng)包括自我診斷來增加設備的自動維護</p><p><b> 優(yōu)化能源
77、損耗</b></p><p> 提高運行過程的性能并且減少設備維護時間</p><p> 為了滿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:基于計算機界面的簡單監(jiān)控畫面讓界面操作更為簡單</p><p> PS2000:隨生產計劃和網(wǎng)絡分配按時間采集數(shù)據(jù)的數(shù)據(jù)采集系統(tǒng)&l
78、t;/p><p> PS4000:為生產計劃而服務的高速數(shù)據(jù)采集系統(tǒng)</p><p> 因此繼電保護部分主要有以下兩個問題來決定:</p><p> ?。╝)本地繼電保護系統(tǒng)需要配置什么樣的功能才能更好的判斷電力系統(tǒng)的正常和非正常運行?</p><p> (b)在未來,電力系統(tǒng)是否能夠自行監(jiān)管和控制呢?</p><p&g
79、t; 對第二個問題的答案決定了繼電保護類型的設計-是更多的使用傳統(tǒng)的固態(tài)模型繼電保護設備,還是更多的引進數(shù)字微控制器模型來實現(xiàn)保護系統(tǒng)。</p><p> 對第一個問題的答案則決定了保護類型的選擇和他們的保護范圍的設定。綜合考慮電力系統(tǒng)行為模型(在穩(wěn)定的傳輸狀態(tài)下)是本指導叢書的主要探討內容。</p><p> 注意,PROSATIN系統(tǒng)的結構是可以通過監(jiān)控系統(tǒng)一步一步的實現(xiàn)的。PR
80、OCOM的保護范圍也是很容易安裝在已存在的測量單元上的,比如本地的PLC設備上。</p><p> 2 高電壓工業(yè)和配電網(wǎng)絡的保護</p><p> 繼電保護在電能網(wǎng)絡中扮演這非常重要的角色,他們是否能夠對器件和全體設備作出正確的保護動作,這為能否提供高質量電能提供了保證。</p><p> 這本指導叢書主要是定義了在電力系統(tǒng)網(wǎng)絡中繼電保護合理布局等問題<
81、;/p><p> 它們由不同類型的過電流繼電器組成,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,以及快速傅里葉變換。使用這種繼電器時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用
82、中。此外繼電器RMSA系列是自控的,他們可以在沒有輔助系統(tǒng)支持的情況下通過CTs來獲得能源的支持。</p><p> 2.1 相間短路保護分析</p><p> 過電流保護是電力系統(tǒng)網(wǎng)絡中使用最基本的保護之一。他們必須要能夠快速的感知在短路情況下產生的電流沖擊變化量并在短時間內做出正確的反應(還要考慮到電應力和熱應力的承受范圍)</p><p> 它的另一個基
83、礎特性就是選擇性,能夠正確反應故障處短路以維持供電網(wǎng)絡的健康穩(wěn)定。</p><p> 2.1.1 時間/電流特性選擇</p><p> 過電流保護繼電器的主要特征是通過他們的短路時間和短路電流特性來表征的,以下有幾種類型選擇方案:</p><p> 獨立或明確的時間繼電器(他們的工作電流是獨立于電流等級的)</p><p> 關聯(lián)或相
84、反限時繼電器(他們的工作電流是由電壓等級來決定的)</p><p> 根據(jù)IEC 255-4標準,最后一種類型的繼電器還可以細分為三種類型:</p><p> 反限時繼電器 (ITG7200系列)</p><p> 強反限時繼電器 (IGT7300系列)</p><p> 超強反限時繼電器 (IGT
85、7400系列)</p><p> 數(shù)字多重過電流繼電器 (RMS700,RMS7000,RMST700和RMSA7000系列)</p><p> 沒有具體的說明規(guī)范用以來對系統(tǒng)的一個或多個類型的繼電器的選擇。然而,時間繼電器可以用于以下幾種情況下使用:</p><p> 電能網(wǎng)絡中含有高電壓等級和短時間的過負荷現(xiàn)象</p><p>
86、存在啟動瞬間電機的啟動勵磁電流侵入電網(wǎng)中</p><p> 繼電器操作必須與大量的保險裝備協(xié)調融合工作時</p><p> 另一方面,獨立時間繼電器在短路電流非常高的情況下,或者在給定的點可能相位差很大的情況下(例如當網(wǎng)絡提供從小型發(fā)電機的短路衰減曲線迅速脫落)它的優(yōu)勢比較大</p><p> 然而,有趣的是,在歐洲大陸一些國家則傾向于使用獨立時間繼電器,而對
87、于盎格魯-撒克遜等一些國家則傾向于使用非獨立時間繼電器。</p><p> 時滯過電流繼電器本身就具有時間選擇性。但是,這還是有一些不足之處,如最靠近電源處故障清除時間會增加,且短路電路電流非常的大。因此有必要減少分級間隔來解決這一問題。</p><p> 電力保護繼電器中的分級間隔通時間通產是400 ms,由以下因素綜合考慮獲得:</p><p><b&
88、gt; 斷路故障的清除時間</b></p><p> 兩繼電器誤動作的總時間</p><p><b> 上級保護的過操作</b></p><p> 大約為100ms的安全空余時間</p><p> 當變壓器饋線保護被認為是使用繼電器有一個瞬時高置單元的明智選擇。這是設置高于二次短路水平和變壓器脈動電
89、流,然后允許將上游的操作時間繼電器減少從而減少電纜短路承受需求。</p><p> 分級間隔可能會減少如果需要,時間小于1秒,使用繼電器與高穩(wěn)定性定時器電路則在250ms左右(ITG 7000或均方根700/7000繼電器)。</p><p> 2.1.2 限時電流速斷</p><p> 在某些情況下,如分級數(shù)量在一個電壓水平下太多將導致故障清除時間要么是太長
90、,使網(wǎng)絡和設備不能承受,或不符合配電部門允許的時候,可以使用一個加速系統(tǒng)。</p><p> 它是由。實現(xiàn)這一傳播所需的信息從下游繼電器到上游通過線路傳遞。故障清除時間是獨立于它的位置,繼電器最低操作時間僅作為一個與下級信息傳送速度有關的一個函數(shù)。</p><p> 繼電器類型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部繼電器相關聯(lián),低設定單元被用來防止過載和完全獨立的邏輯。因此在故障發(fā)生在沒有繼電器保護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 差動保護</p><p> 這一保護的原則是比較同一相上電流的大小,單由兩個繼電保護裝置來執(zhí)行保護。它的優(yōu)點主要有以下幾個:</p><p> 瞬
92、時動作,因為它只對故障內部做出反應</p><p> 它能夠識別電能的方向傳輸,特別是在多電源的情況下</p><p> 它也可能允許消除分級,從而減少故障時上游網(wǎng)絡跳閘時間。然而為了平衡這些優(yōu)點,它需要飛行員鏈接(SOLKOR-RF)和匹配類X與穩(wěn)定電阻電流互感器通常推薦變壓器的差動保護,旋轉機器和匯流。</p><p> 電纜的差動繼電器保護,SOLKOR
93、-RF類型,操作一個特殊原則:</p><p> 他們不單獨比較每個階段的電流,而是三個電流的結合</p><p> 這種系統(tǒng)的優(yōu)點是,只有一跟通信電纜是必需的,但不同相間的故障對其操作也是不同的</p><p> 2.1.4 方向保護</p><p> 當變電所需要支持兩個電纜或是兩組平行變壓器的時候,保護系統(tǒng)會保護這兩個被保護系統(tǒng)
94、(上游變電站)同時運行故障其中之一。獲得選擇性保護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電流繼電器類型RMSD7921或ITD7111應安裝在每個新來者。</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,并允許過流單元操作如果這相角顯示當前在相反的方向。</p><p> 顯示7000年繼電器、輸入信號的FFT處理,檢查電流和電壓的相角之間的根本
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