變電站的系統(tǒng)過電壓防護技術(shù)文獻翻譯.doc

畢業(yè)論文(設(shè)計)文獻翻譯本翻譯源自于： /p-144919607.html 畢業(yè)設(shè)計名稱： 變電站數(shù)據(jù)采集系統(tǒng)設(shè)計 外文翻譯名稱： 變電站系統(tǒng)過電壓防護技術(shù) 學(xué) 生 姓 名 ： 趙文浩 院 (系)： 電子信息學(xué)院 專 業(yè) 班 級 ： 電氣10803 指 導(dǎo) 教 師 ： 唐桃波輔 導(dǎo) 教 師 ： 唐桃波時 間 ： 至 變電站系統(tǒng)過電壓防護技術(shù)學(xué)生：趙文浩，電子信息學(xué)院指導(dǎo)教師：唐桃波，長江大學(xué)變電站的過電壓保護是以電子信息系統(tǒng)為保護核心，為被保護設(shè)備構(gòu)建一個均壓等電位系統(tǒng)，并通過各級過電壓浪涌保護器逐級把電流泄放入大地，使變電站設(shè)備全和可靠地運行。1 變電站過電壓防護近年來，變電站的通信、通信系統(tǒng)、繼電保護系統(tǒng)、后臺管理模塊經(jīng)常發(fā)生過電壓損毀事件，究其原因主要是其相關(guān)系統(tǒng)和弱電產(chǎn)品過電壓防護水平較弱，甚至根本沒有過電壓防范技術(shù)措施，其后果對電網(wǎng)的安全運行帶來了較大負面影響。隨著綜合自動化系統(tǒng)和通信自動化系統(tǒng)等二次弱電系統(tǒng)在變電站的廣泛應(yīng)用，這類電子系統(tǒng)(設(shè)備)元器件的集成度愈來愈高，信息存儲量愈來愈大，速度和精度不斷提高，而工作電壓只有幾伏，信息電流僅為微安級，因而對外界干擾極其敏感，特別對雷電等電磁脈沖和過電壓的耐受能力很低。當雷電等過電壓和伴隨的電磁場達到某一閥值時，輕則引起系統(tǒng)失靈，重則導(dǎo)致設(shè)備或其元器件永久性損壞。盡管雷電直擊電子系統(tǒng)(設(shè)備)的可能性不大，但是雷擊附近大地、建筑物、交流供電線路和空中雷云放電時直接形成的，或者由于靜電感應(yīng)及電磁感應(yīng)形成的沖擊過電壓，都有可能通過與之相連的電力線路、信號線路或接地系統(tǒng)，通過各種接口，以傳導(dǎo)、耦合、輻射等形式，侵入電子系統(tǒng)(設(shè)備)并釀成嚴重的干擾或事故。因此，加強和改進電子系統(tǒng)(設(shè)備)的防護，盡量減小其遭受雷電等沖擊干擾損害造成的直接損失和間接損失，已成為當今亟待解決的問題。2 過電壓保護設(shè)計IEC(國際電工委員會)TC81技術(shù)委員會將防雷分為外部防雷和內(nèi)部防雷兩個部分，外部防雷是指避雷針(或避雷帶、避雷網(wǎng))、引下線和接地系統(tǒng)，是被保護物體免受直接雷擊；內(nèi)部防雷則是防止雷電和其他內(nèi)部過電壓侵入設(shè)備造成的毀壞。一個完善的防雷及過電壓保護系統(tǒng)必須綜合運用泄流(分流)、均壓(等電位)、屏蔽(隔離)、接地、限壓(箝位)保護等各項技術(shù)，按照外部防雷和內(nèi)部防雷的原則，根據(jù)防護對象的特點，靈活應(yīng)用，采取具體措施，構(gòu)成一個完整的防護體系。變電站內(nèi)的過電壓形式主要有：雷電過電壓、工頻過電壓及諧振過電壓、操作過電壓等，這些過電壓以傳導(dǎo)或電磁感應(yīng)的方式在線路及設(shè)備上形成危險的過電壓，特別是雷電過電壓，雷擊變電站時，會在低壓供電系統(tǒng)及弱電系統(tǒng)產(chǎn)生很強的感應(yīng)過電壓，同時使變電站的地電位升高(例如：變電站的接地電阻為1 Q，雷電流為10 kA，則地電位為10 kV)，因地電位升高造成對線路及設(shè)備的反擊而損壞線路及設(shè)備的事件時有發(fā)生，因此，盡管變電站的外部防雷系統(tǒng)(避雷針引下線及接地裝置)符合國家及部頒標準的要求，且其綜合自動化和通信自動化等二次弱電系統(tǒng)也采取了諸如屏蔽、接地、隔離、濾波等措施，但卻不能完全避免強大的雷電過電壓及電壓反擊對系統(tǒng)造成的干擾和破壞，因此，變電站二次弱電系統(tǒng)內(nèi)部防雷及過電壓也必須采取相應(yīng)的防護措施，按照IEC內(nèi)部防雷EMP的分區(qū)，對設(shè)備的電源線、信號線、數(shù)據(jù)線等加裝內(nèi)部防雷及過電壓器件，防止雷電感應(yīng)、雷電流沿線竄人、電壓反擊、浪涌過電壓等瞬間暫態(tài)過電壓造成系統(tǒng)故障及損壞電子設(shè)備。浪涌過電壓保護器根據(jù)其接線方式分為串聯(lián)和并聯(lián)兩種，使用串聯(lián)浪涌過電壓保護器時，有可能存在由于傳輸信號不匹配的原因?qū)е聦鬏斝盘栍懈蓴_的情況，特別是數(shù)據(jù)通信接口在串人浪涌過電壓防護器后，會產(chǎn)生數(shù)據(jù)無法正常通訊。因此，在數(shù)據(jù)通訊接I：I中串人浪涌過電壓防護器后，必須對數(shù)據(jù)的傳輸情況進行認真檢查，如發(fā)現(xiàn)數(shù)據(jù)無法正常傳輸，則有可能是由于不匹配的原因?qū)е聦鬏斝盘柕母蓴_，應(yīng)更換相匹配的浪涌過電壓防護器。如果在使用浪涌過電壓防護器時采用并聯(lián)方式，基本上不存在上述情況，但這種接線方式對浪涌過電壓防護器的技術(shù)要求更高。3 變電站系統(tǒng)過電壓防護31 站用電系統(tǒng)過電壓防護安裝在變電站內(nèi)的通信調(diào)度自動化系統(tǒng)大多采用交流電源或直流電源為其設(shè)備供電，在其整流環(huán)節(jié)，一般有較大容量的濾波電容，對瞬態(tài)過電壓沖擊有一定的吸收作用，站用變壓器低壓側(cè)到站用饋電屏之間采用的是屏蔽電纜且設(shè)備都有良好的接地，運用現(xiàn)代防雷技術(shù)來分析，必須增加回路的分流措施，因為其工作接地、保護接地都與其它電氣設(shè)備采用同一接地裝置，而且設(shè)備都處于LPZOB區(qū)，電磁脈沖強度相對較強，在站用變低壓側(cè)雖然有防止線路侵人波的避雷器，但殘壓高，因此在變電站遭受雷擊時，通過線路耦合和地電位升高而造成的反擊過電壓依然存在，而且高壓側(cè)的殘壓高達幾千伏，因此必須對這些調(diào)度自動化設(shè)備的供電回路進行過電壓保護。根據(jù)雷電防護區(qū)域的劃分原則，變電站內(nèi)二次設(shè)備供電系統(tǒng)感應(yīng)雷電過電壓的防護可以按兩級(B、C級)來進行分流保護。B級防雷一般采用具有較大通流容量的防雷裝置，可以將較大的雷電流泄散入地，從而達到限流的目的，同時將過電壓減小到一定的程度，c級防雷采用具有較低殘壓的防雷裝置，可以將回路中剩余的雷電流泄散人地，達到限制過電壓的目的，使過電壓減小到設(shè)備能耐受的水平。電源系統(tǒng)的防護主要是抑制雷電及操作在電源回路上產(chǎn)生的浪涌和過電壓。根據(jù)變電站的現(xiàn)狀，對變電站的二次系統(tǒng)感應(yīng)雷及操作過電壓采用兩級防護。由于變電站多建在較為空曠的區(qū)域，電磁強度相對較強，電力線路和通信電纜是很容易遭受到感應(yīng)雷電的襲擊，感應(yīng)過電壓沿著電力線路和通信線路進人設(shè)備，從而將設(shè)備損壞，因此，交流母線處加裝第一級電源防護(B級)是為了保證整個控制室的安全，并且將80的過電壓泄散到大地，起到初級保護的作用，但在交流饋線上仍有部分過電壓和B級電源防雷的殘壓加在線路上，因此必須在重要的交流饋線處(直流充電屏、UPS等)進行c級電源防護，從而將過電壓抑制到后端用電設(shè)備能夠耐受的水平。311 第一級防護處理措施防護位置：據(jù)1EC1312(雷電電磁脈沖的防護中的雷電保護區(qū)域的劃分原則。避雷器的安裝位置應(yīng)在不同保護區(qū)的交界處，對于此網(wǎng)絡(luò)即第一級防護應(yīng)設(shè)在交流母線處。在兩根母線上各加裝一個同型號的B級三相電源浪涌過電壓保護器。安裝位置：交流母線(機柜內(nèi))。312 第二級防護處理措施對于較為重要的交流饋線上的設(shè)備，此處為直流充電屏，加裝c級三相電源避雷器。由于直流充電屏是兩路交流供電，所以在直流充電屏處加裝兩個同型號的c級三相電源浪涌過電壓保護器。安裝位置宜選擇在直流充電屏交流電源空氣開關(guān)處。32 綜合自動化系統(tǒng)過電壓防護防護位置：微機型綜合自動化系統(tǒng)承受過電壓的能力極低，幾百伏的過電壓就足以將設(shè)備損壞，因此必須對高壓側(cè)避雷器的殘壓(幾千伏)進行進一步的抑制，以滿足設(shè)備絕緣水平的需要，同時由于地電位升高而感應(yīng)到電源回路零線的過電壓也高達上千伏，因此必須在采用交流綜合自動化系統(tǒng)的交流回路上加裝c級單相浪涌過電壓保護器。安裝位置宜選擇在綜合自動化屏交流電源空氣開關(guān)處。33 不間斷電源設(shè)備(UPS)過電壓防護防護位置：由于內(nèi)部計算機系統(tǒng)、集線器、監(jiān)控設(shè)備、電能量計費系統(tǒng)等均經(jīng)由UPS 供電保護，為了保障以上微電子設(shè)備的安全，故在UPS 電源裝置前端加裝c級浪涌過電壓保護器。選用型號：選用(UPS為單相電源輸入時)C級單相電源浪涌過電壓保護器或(UPS 為三相電源輸入時)的c級三相電源浪涌過電壓保護器。安裝位置宜選擇在UPS 電源進線前端。34 通信接口過電壓防護通信接口過電壓防護同電網(wǎng)供電系統(tǒng)相比，此回路對過電壓的敏感程度要高得多，且這些設(shè)備在有過電壓的情況下顯得非常脆弱。設(shè)備的絕緣耐受水平也相當?shù)?。與這些設(shè)備相連的有信號線、數(shù)據(jù)線、測量和控制線路，并且這些線路基本上是處于LPZOB區(qū)域，也有穿過LVZOA區(qū)域的，線路上的感應(yīng)過電壓相對較強，根據(jù)IEC的測試，當電磁場強度增大到007GS時，微型計算機設(shè)備將產(chǎn)生誤動，丟失數(shù)據(jù)。而且這些回路運行的安全與否直接關(guān)系到一次系統(tǒng)設(shè)備的安全，因此須對重要回路的接口進行過電壓防護。341 微機遠動設(shè)備接口過電壓防護防護位置：由于變電站微機遠動裝置采用分布分散式結(jié)構(gòu)。由遙信模塊、智能遙測模塊、智能遙控模塊、智能遙調(diào)模塊組成。各單元模塊都裝設(shè)在不同的自動化屏內(nèi)，模塊之間通過RS232接口或現(xiàn)場總線進行通信。這些接口線路都處在室內(nèi)，設(shè)備接口線路的距離較短，因此不會感應(yīng)到較強的過電壓，但是各自動化設(shè)備與其它二次設(shè)備(測量單元、計算機等)有電氣連接，當其它二次設(shè)備感應(yīng)到很強的感應(yīng)過電壓時，將會反擊到這些自動化設(shè)備的通信接口上，從而使設(shè)備接口電路損壞，因此有必要在這些設(shè)備的接口上加裝RS232的浪涌過電壓保護器。安裝位置宜選擇在微機遠動裝置通信線路接口處。342 電能量計費系統(tǒng)信號過電壓保護防護位置一：變電站采用多功能電子電能表進行電能量采集，電子電能表承受過電壓的水平極低。由于電能表與站內(nèi)微機遠動設(shè)備的通信采用RS232的接口，其通信線路較長，又處在LVZOB區(qū)域，在變電站附近或變電站遭受直接雷擊時，將感應(yīng)出較強的感應(yīng)過電壓，為了防止設(shè)備的損壞。在靠近電子電能表的RS232端口加裝RS232的浪涌過電壓保護器。安裝位置宜選擇在靠近電子電能表的RS232端口處。防護位置二：電子電能表采集的信息通過集中采集器的MODEM(調(diào)制解調(diào)器)由電話線將數(shù)據(jù)傳送到遠端，由于電話線路從室外引入，線路上感應(yīng)到的感應(yīng)雷電流相對較強，容易將調(diào)制解調(diào)器設(shè)備的接口損壞，因此必須在調(diào)制解調(diào)器的電話線路接口處加裝一個接口浪涌過電壓保護器。安裝位置宜選擇在內(nèi)線電話出線端和外線電話的人線端。343 遠方通信接口過電壓保護防護位置：由于變電站基本采用無人值守。對一次回路的各種保護、測量、控制、調(diào)節(jié)信號通過光纖、數(shù)據(jù)通信網(wǎng)絡(luò)或載波向遠方(省調(diào)、地調(diào)、集控站等)傳送數(shù)據(jù)。如果采用載波，由于載波機與微機自動化裝置的信號連接線路相對較長，在變電站附近或變電站遭受直接雷擊時，處在LPZOB區(qū)的通信線路將感應(yīng)出較強的感應(yīng)過電壓，因此必須在靠近微機自動化裝置的信號接I：I端加裝信號避雷器，同時處在LPZOB區(qū)并延伸到LPZOA區(qū)的通信線路(DDN、X25)非常容易感應(yīng)上雷電過電壓，也必須加裝浪涌過電壓保護器。安裝位置宜選擇在遠動裝置通信線路接口處。變電站系統(tǒng)過電壓防護問題是近年來提出的一個新課題，以上僅是結(jié)合本單位相關(guān)現(xiàn)場實際情況對防護技術(shù)措施的初步探討，還需在不斷吸取實際運行經(jīng)驗進行總結(jié)分析和不斷完善，希望在今后新建變電站或者對老舊變電站進行綜合自動化改造時，加強對過電壓防護系統(tǒng)的同時規(guī)劃和設(shè)計，確保設(shè)備和電網(wǎng)的安全穩(wěn)定運行。Substation system over-voltage protection technologySecond substation equipment over-voltage protection on electronic information system for the protection of core equipment for the construction of a protected both pressure and other potential system, and through all levels of over-voltage surge protectors of the current step by step into the land of China, Substation secondary safety equipment and reliable operation.1 second over-voltage substation protection In recent years, the substation communications, communications systems, protection systems, background management module frequent over-voltage damage, the main reason for this is weak and its related systems products over-voltage protection level is weak, or no guard against over-voltage Technical measures, the consequences for the safe operation of power grids bring about a greater negative impact. With integrated automation systems and automation systems such as communication systems in the substation weak secondary by the wider use of such electronic systems (equipment) components of the integrated more and more, the growing volume of information storage, speed and accuracy of the Increased and operates only a few volts, current information only microamp level, thus extremely sensitive to outside interference, especially the lightning and electromagnetic pulse, such as over-voltage tolerance is low. When thunder and lightning, such as over-voltage and accompanied by the electromagnetic fields reach a certain threshold, ranging from system failure caused, resulted in heavy equipment or permanent damage to its components. Despite the thunder and lightning viewpoint of electronic systems (equipment) is unlikely, but lightning strike near the land, buildings, communication and air supply line directly Leiyun discharge form, or because of electrostatic induction and the impact of electromagnetic induction formation of over-voltage, There might be connected to the power lines, signal lines or grounding system, through various interfaces to transfer, coupling, radiation and other forms of invasive electronic system (equipment) and lead to serious disturbances or incidents. Therefore, strengthening and improving the electronic system (equipment) protection, to minimize the impact of interference by lightning and other damage caused direct losses and indirect losses, has become the urgent need to solve the problem.2 over-voltage protection design IEC (International Electrotechnical Commission) TC/81 mine technical committee will be divided into internal and external mine mine in two parts, the external mine is lightning rod (or with lightning, lightning network), Yin Xiaxian and grounding system, Objects to be protected from direct lightning strikes, mine is to prevent internal lightning and other internal over-voltage damage caused by invasive equipment. A comprehensive mine and over-voltage protection systems must be integrated use of discharge (segregation), both pressure (and other potential), shielding (isolation), grounded, limit pressure (clamp) protection, and other technology, in accordance with the external mine And the principle of internal mine, in accordance with the targets of protective features, flexible application to take concrete measures, constitute a complete protection system. Over-voltage substation in the form are: Lightning over-voltage, the resonant frequency over-voltage and over-voltage, over-voltage operation, these over-voltage transmission or electromagnetic induction to the way the lines and equipment on a dangerous over-voltage, in particular, Lightning over-voltage, lightning substation, in the low-voltage power supply system and weak system to produce a strong over-voltage sensor, while the substation to potential rise (for example: the substation grounding resistance to 1 Q, lightning current 10 kA, while the potential for 10 kV), due to the increased potential of the counter lines and equipment damaged lines and equipment and the events have occurred, therefore, despite the substation outside the mine system (lightning rod. Yin Xiaxian And grounding devices) in line with national standards and the requirements of Buban, and the integrated automation and communications automation systems, such as weak secondary have been taken, such as shielding, grounding, isolation, filtering, and other measures, but it can not completely avoid over-voltage powerful lightning And voltage of the system counter the disruption caused damage and, therefore, the second weak system substation and a mine-voltage must also take the appropriate protective measures, in accordance with the IEC within the mine area EMP, the devices power cord, signal Lines, data lines, and the installation of lightning protection and internal over-voltage devices to prevent lightning sensors, channeling people along the lightning current, voltage counterattack, such as transient voltage surge too transient over-voltage caused by a fault and damaged electronic equipment. Over-voltage surge protection in accordance with its connection mode is divided into two series and parallel, the use of over-voltage surge protection tandem with, there may exist because of signal transmission does not match the causes of transmission of the signal interference, in particular data Communication Interface in the series were over-voltage surge protection in place, will have the normal data communications. Therefore, the data communications access I: I in the series were over-voltage surge protection in place, the transmission of data must be carried out conscientiously check if the data are not normal transmission, it may be due to the reasons do not match the transmission signal Interference, should be replaced to match the over-voltage surge protection for. If the use of over-voltage surge protection for use of parallel, the situation is basically non-existent, but the connection mode of over-voltage surge protection for higher technical requirements.3 secondary system over-voltage substation protection 3.1 points over-voltage electricity system protection Substation installed in the communications dispatch automation systems are used AC power or a DC power supply equipment for the rectification of its links are generally larger capacity filter capacitance, the transient over-voltage shock absorption of a certain extent, the station Low-voltage transformer side go to feed between the screen using a shielded cable and equipment have a good grounding, the use of modern technology to analyze mine, we must increase the circuits segregation measures, because its grounding, protection and other electrical grounding all Grounding devices using the same equipment, and equipment are in a LPZOB, the relative strength of strong electromagnetic pulse, the station changed to prevent low-pressure side although there are lines intrusive wave arrester, but the residual pressure high, in the substation of lightning, through the line Coupling and the potential rise caused by over-voltage counterattack still exist, and high-pressure side of the residual pressure as high as several thousand volts, it is necessary to these scheduling automation equipment for the power supply over-voltage circuit protection. Lightning Protection in accordance with the principle of regional division, substation equipment in the secondary power supply system over-voltage sensors lightning protection may be two (B, C level) for the protection of segregation. B-mine use is generally greater flow capacity of the mine installations, the Lightning could be more casual Liuxie people, to achieve the objective of current limit, over-voltage at the same time will reduce to a certain extent, c-mine use With lower residual pressure of the mine installations, you can loop in the remaining scattered lightning Liuxie people, to limit the purpose of over-voltage, over-voltage equipment can be reduced to the level of tolerance. The main power supply system is inhibited lightning protection and operation of the power back to the road and over-voltage surge. According to the substation status of the substation of the second mine-sensing system and the operation and use of two over-voltage protection. As build more substations in the region more open, relatively strong electromagnetic strength, power lines and communication cables are very vulnerable to lightning attacks sensors, sensors along the over-voltage power lines and communication lines into one device, which will damage equipment, Therefore, the exchange of first-class bus to install the power protection (B level) is to ensure the safety of the entire control room, and 80 percent of the over-voltage China, scattered to the earth, play a primary role in the protection, but are still in the exchange of feeder Some of the B-level power supply voltage and mine the residual pressure increases on-line and must therefore be important in the exchange of feeder lines (DC charging screen, UPS, etc.) c-level power protection, which would curb over-voltage electrical equipment to back-end To the level of tolerance.Protective location: It is 1 EC1312 (LEMP protection in the region of lightning protection principles. Arrester installation should be in different locations at the junction of protected areas, this network, the first-class protection should be located in the bus exchange. In Two on the bus with the installation of a B-class models of a three-phase power supply voltage surge protector. Install Location: AC bus (cabinet). 3.1.2 second-class protection measures to deal with For the more important feeder lines on the exchange of equipment, here for the DC charge screen, the installation of c-level three-phase power arrester. As DC charging screen is two-way exchange of electricity supply, so the screen in the DC charge with the installation of two models of c-level three-phase power supply over-voltage surge protector. Installation location should choose the DC charge screen open exchange of air power Commissioner Office. 3.2 integrated automation system over-voltage protection Protective position: Computer-based integrated automation systems ability to bear a very low voltage, several hundred volts of over-voltage is enough to damage the equipment, so must the high side arrester the residual pressure (thousands of volts) to further curb to meet equipment Insulation level of need, and because of the potential rise to power and the induction loop is also over-voltage line up on KV, to be used in the exchange of integrated automation system to the exchange on the c-level single-phase installation of a surge Voltage protection. Location should choose to install automated-ping in the Composite Air switch the AC power.3.3 did not ask off power supplies (UPS) over-voltage protection Protection here: because of the internal computer systems, hubs, monitoring equipment, electric energy billing systems and so on through the UPS power supply protection, in order to protect the safety of these micro-electronics equipment, the UPS power supply device in front of the installation of a c-Surge Voltage protection. Optional models: The (UPS for single-phase power input) C-class single-phase power surge or over-voltage protection (UPS for the three-phase power input) of c-level three-phase power supply over-voltage surge protector. Installation should choose the location of UPS into the front line. 3.4 communication interface over-voltage protection Communication Interface over-voltage protection compared with the grid supply system, this over-voltage circuit on the degree of sensitivity is much higher, and these are over-voltage equipment in the circumstances it is very fragile. Equipment insulation tolerance level is very low. With the equipment connected to a signal line, data lines, measurement and control lines, and these are basically in line LPZOB region, but also through the LVZOA region, on the lines of sensors over-voltage relatively strong, according to the IEC test, when the electromagnetic field Strength increased to 0.07 GS, will have a micro-computer equipment malfunction, loss of data. And the safety of these circuits is directly related to a system of safety equipment, so important to be on the interface circuit over-voltage protection. 3.4.1 remote computer interface devices over-voltage protection Protective position: As substation computer remote installations scattered distribution structure. From remote modules, intelligent telemetry module, intelligent remote control module, intelligent remote-module. The modules are installed in different automated-ping, through the RS232 interface between the modules or field bus communication. These interfaces are in the indoor circuit, equipment interface circuits shorter the distance, so there will be no more sensors to the over-voltage, but the automation equipment and other secondary equipment (measurement unit, computer, etc.) have electrical connections, when Other secondary equipment sensors to a strong over-voltage sensors, will be counter to these automation equipment, communications interface, so that damage to equipment interface circuits, it is necessary in these devices RS