基础防雷外文资料翻译 精品

附件2：Fundamentals of Lightning ProtectionIntroductionLightning is a capricious, random and unpredictable event. Its' physical characteristics include current levels sometimes in excess of 400 kA, temperatures to 50,000 degrees F., and speeds approaching one third the speed of light. Globally, some 2000 on-going thunderstorms cause about 100 lightning strikes to earth each second. USA insurance company information shows one homeowner's damage claim for every 57 lightning strikes. Data about commercial, government, and industrial lightning-caused losses is not available. Annually in the USA lightning causes more than 26,000 fires with damage to property (NLSI estimates) in excess of $5-6 billion.The phenomenology of lightning strikes to earth, as presently understood, follows an approximate behavior:1. The downward Leaders from a thundercloud pulse towards earth seeking out active electrical ground targets.2. Ground-based objects (fences, trees, blades of grass, corners of buildings, people, lightning rods, etc., etc.) emit varying degrees of electric activityduring this event. Upward Streamers are launched from some of these objects. A few tens of meters off the ground, a "collection zone" is established according to the intensified local electrical field.3. Some Leader(s) likely will connect with some Streamer(s). Then, the "switch" is closed and the current flows. We see lightning.Lightning effects can be direct and/or indirect. Direct effects are from resistive (ohmic) heating, arcing and burning. Indirect effects are more probable. They include capacitive, inductive and magnetic behavior. Lightning "prevention" or "protection" (in an absolute sense) is impossible.A diminution of its consequences, together with incremental safety improvements, can be obtained by the use of a holistic or systematic hazard mitigation approach, described below in generic terms.Lightning RodsIn Franklin's day, lightning rods conducted current away from buildings to earth. Lightning rods, now known as air terminals, are believed to send Streamers upward at varying distances and times according to shape, height and other factors. Different designs of air terminals may be employed according to different protection requirements. For example, the utility industry prefers overhead shielding wires for electrical substations. In some cases, no use whatsoever of air terminals is appropriate (example: munitionsbunkers). Air terminals do not provide for safety to modern electronics within structures.Air terminal design may alter Streamer behavior. In equivalent e-fields, a blunt pointed rod is seen to behave differently than a sharp pointed rod. Faraday Cage and overhead shield designs produce yet other effects. Air terminal design and performance is a controversial and unresolved issue. Commercial claims of the "elimination" of lightning deserve a skeptical reception. Further research and testing is on-going in order to understand more fully the behavior of various air terminals.Downconductors, Bonding and ShieldingDownconductors should be installed in a safe manner through a known route, outside of the structure. They should not be painted, since this will increase impedance. Gradual bends (min. eight inch radius) should be adopted to avoid flashover problems. Building steel may be used in place of downconductors where practical as a beneficial part of the earth electrode subsystem.Bonding assures that all metal masses are at the same electrical potential.All metallic conductors entering structures (AC power, gas and water pipes, signal lines, HVAC ducting, conduits, railroad tracks, overhead bridge cranes, etc.) should be integrated electrically to the earth electrodesubsystem. Connector bonding should be thermal, not mechanical. Mechanical bonds are subject to corrosion and physical damage. Frequent inspection and ohmic resistance measuring of compression and mechanical connectors is recommended.Shielding is an additional line of defense against induced effects. It prevents the higher frequency electromagnetic noise from interfering with the desired signal. It is accomplished by isolation of the signal wires from the source of noise.GroundingThe grounding system must address low earth impedance as well as low resistance. A spectral study of lightning's typical impulse reveals both a high and a low frequency content. The high frequency is associated with an extremely fast rising "front" on the order of 10 microseconds to peak current. The lower frequency component resides in the long, high energy "tail" or follow-on current in the impulse. The grounding system appears to the lightning impulse as a transmission line where wave propagation theory applies.A single point grounding system is achieved when all equipment within the structure(s) are connected to a master bus bar which in turn is bonded to the external grounding system at one point only. Earth loops and differential risetimes must be avoided. The grounding system should be designed to reduce ac impedance and dc resistance. The shape and dimension of the earth termination system is more important a specific value of the earth electrode. The use of counterpoise or "crow's foot" radial techniques can lower impedance as they allow lightning energy to diverge as each buried conductor shares voltage gradients. Ground rings around structures are useful. They should be connected to the facility ground. Exothermic (welded) connectors are recommended in all circumstances.Cathodic reactance should be considered during the site analysis phase.Man-made earth additives and backfills are useful in difficult soils circumstances: they should be considered on a case-by-case basis where lowering grounding impedances are difficult an/or expensive by traditional means. Regular physical inspections and testing should be a part of an established preventive maintenance program.Transients and SurgesOrdinary fuses and circuit breakers are not capable of dealing with lightning-induced transients. Lightning protection equipment may shunt current, block energy from traveling down the wire, filter certain frequencies, clamp voltage levels, or perform a combination of these tasks. Voltage clamping devices capable of handling extremely high amperages of the surge, as well as reducing the extremely fast rising edge (dv/dt and di/dt) ofthe transient are recommended. Adopting a fortress defense against surges is prudent: protect the main panel (AC power) entry; protect all relevant secondary distribution panels; protect all valuable plug-in devices such as process control instrumentation, computers, printers, fire alarms, data recording & SCADA equipment, etc. Further, protect incoming and outgoing data and signal lines. Protect electric devices which serve the primary asset such as well heads, remote security alarms, CCTV cameras, high mast lighting, etc. HVAC vents which penetrate one structure from another should not be ignored as possible troublesome electrical pathways. Surge suppressors should be installed with minimum lead lengths to their respective panels. Under fast rise time conditions, cable inductance becomes important and high transient voltages can be developed across long leads.In all instances, use high quality, high speed, self-diagnosing protective components. Transient limiting devices may use a combination of arc gap diverters-metal oxide varistor-silicon avalanche diode technologies. Hybrid devices, using a combination of these technologies, are preferred. Know your clamping voltage requirements. Confirm that your vendor's products have been tested to rigid ANSI/IEEE/ISO9000 test standards. Avoidlow-priced, bargain products which proliferate the market (caveat emptor). DetectionLightning detectors, available at differing costs and technologies, sometimes are useful to provide early warning. An interesting application is when they are used to disconnect from AC line power and to engage standby power, before the arrival of lightning. Users should beware of over-confidence in such equipment which is not perfect and does not always acquire all lightning data.EducationLightning safety should be practiced by all people during thunderstorms. Preparedness includes: get indoors or in a car; avoid water and all metal objects; get off the high ground; avoid solitary trees; stay off the telephone. If caught outdoors during nearby lightning, adopt the Lightning Safety Position (LSP). LSP means staying away from other people, taking off all metal objects, crouching with feet together, head bowed, and placing hands on ears to reduce acoustic shock.Measuring lightning's distance is easy. Use the "Flash/Bang" (F/B) technique. For every count of five from the time of seeing the lightning stroke to hearing the associated thunder, lightning is one mile away. A F/B of 10 = 2 miles; a F/B of 20 = 4 miles, etc. Since the distance from Strike A to Strike B to Strike C can be as much as 5-8 miles. Be conservative and suspend activities when you first hear thunder, if possible. Do not resumeoutdoor activities until 20 minutes has past from the last observable thunder or lightning.Organizations should adopt a Lightning Safety Policy and integrate it into their overall safety plan.TestingModern diagnostic testing is available to mimic the performance of lightning conducting devices as well as to indicate the general route of lightning through structures. This testing typically is low power, 50 watt or less. It is traceable, but will not trip MOVs, gas tube arrestors, or other transient protection devices. Knowing the behavior of an event prior to occurrence is every businessman's earnest hope. With such techniques, lightning paths can be forecast reliably.Codes & StandardsThe marketplace abounds with exaggerated claims of product perfection. Frequently referenced codes and installation standards are incomplete, out dated and promulgated by commercial interests. On the other hand IEC, IEEE, MIL-STD, FAA, NASA and similar documents are supported by background engineering, the peer-review process, and are technical in nature.SummaryIt is important that all of the above subjects be considered in a lightning safety analysis. There is no Utopia in lightning protection. Lightning may ignore every defense man can conceive. A systematic hazard mitigation approach to lightning safety is a prudent course of action.References1.API 2003, Protection Against Ignitions Arising out of Static, Lightning,and Stray Currents, American Petroleum Institute, Washington DC,December 1991.2.Golde, G.H., Lightning, Academic Press, NY, 1977.3.Hasse, P., Overvoltage Protection of Low Voltage Systems, PeterPeregrinus Press, London, 1992.4.Hovath, Tibor, Computation of Lightning Protection, John Wiley, NY,1991.5.IEEE Std 1100, Powering and Grounding of Sensitive ElectronicEquipment, IEEE, NY, NY. 1992.6.KSC-STD-E-0012B, Standard for Bonding and Grounding, EngineeringDevelopment Directorate, John F. Kennedy Space Center, NASA, 1991.7.Morris, M.E., et.al., Rocket-Triggered Lightning Studies for the Protectionof Critical Assets, IEEE Transactions on Industry Applications, Vol. 30,No. 3, May/June 1994.8.Sunde, E.D. Earth Conduction Effects in Transmission Systems, D. VanNostrand Co., NY, 1949.9.Towne, D., Wave Phenomena, Dover Publications, NY.10.Uman, Martin, Lightning, Dover Publications, NY, 1984.附件1：外文资料翻译译文基础防雷简介闪电是一个反复无常，随机和不可预测的事件。

雷电防护第1部分：总则IEC: Protection Against LightningPart1:General principles目录前言 (3)简介 (4)1.范围和目标 (5)2.规范性参考文件 (5)3.术语和定义 (5)4.雷击电流参数 (11)5.雷电的损害 (11)5.1 对建筑物的损害5.2 对公共设施的损害5.3 损失类型6.对防雷的需求和经济利益 (14)6.1 雷电防护需求6.2 雷电防护的经济利益7.防护措施 (14)7.1 减少接触和跨步电压对活体损害的防护措施7.2 减少物质损害的防护措施7.3 减少电气和电子系统失效的防护措施7.4 防护措施选择8. 对建筑物和公共设施防护的基本准则 (16)8.1 雷电防护等级（LPL）8.2 雷电防护区（LPZ）8.3 建筑物防护附录A（资料性）雷击电流参数 (25)附录B（资料性）供分析用的雷击电流的时间函数 (34)附录C（规范性）供试验用的雷击电流的模拟 (38)附录D（规范性）对LPS部件受雷电影响的模拟及其试验参数 (42)前言1) IEC（国际电工委员会）是世界性标准化组织，其所有成员为国家电工委员会。

它致力于促进在电气和电子领域内所有关于标准化问题的国际合作。

为着本目标及其它相关活动，IEC发行公布国际标准。

前期工作委托给技术委员会；任何IEC组成成员如对该问题感兴趣，可参与准备工作。

与IEC有交往的国际性的、政府间的、以及民间组织也可参与该工作。

IEC与ISO在两组织已达成的协议条件下保持着密切合作。

2）IEC关于技术问题的正式决定或协议，尽可能地表述为相关的国际公认标准。

因每一技术委员会拥有来自代表各国利益的各国委员会的代表。

3）为方便国际间合作，产生的文件以各国委员会易接受的形式印发，如：标准、技术规格、技术报告或指南形式等。

4）为促进国际间的统一化，IEC成员致力于在其各自国家和地区最大可能地应用IEC国际标准。

电子信息系统electronic information system：由计算机、有/线通信设备、处理设备、控制设备及其相差的配套设备、设施（含网络）等的电子设备构成的，按照一定应用目的和规则对信息进行采集、加工、存储、传输、检索等处理的人机系统。

电磁兼容性electromagnetic compatibility(EMC)：设备或系统在其电磁环境中能正常工作，且不对环境中的其他设备和系统构成不能承受的电磁干扰的能力。

电磁屏蔽electromagnetic shielding：用导电材料减少交变电磁场向指定区域穿透的屏蔽。

防雷装置lightning protection system(LPS)：外部和内部雷电防护装置的统称。

外部防雷装置external lightning protection system：由接闪器、引下线和接地装置组成，主要用以防直击雷的防护装置。

内部防雷装置internal lighting protection system：由等电位连接系统、共用接地系统、屏蔽系统、合理布线系统、浪涌保护器等组成，主要用于减小和防止雷电流在需防空间内所产生的电磁效应。

共用接地系统common earthing system：将各部分防雷装置、建筑物金属构件、低压配电保护线(PE)、等电位连接带、设备保护地、屏蔽体接地、防静电接地及接地装置等连接在一起的接地系统。

等电位连接equipotent bonding(EB)：设备和装置外露可导电部分的电位基本相等的电气连接。

等电位连接带equipotent bonding bar(EBB)：将金属装置、外来导电物、电力线路、通信线路及其他电缆连于其上以能与防雷装置做等电位连接的金属带。

自然接地体natural earthing electrode：具有兼作接地的但不是为此目的而专门设置的与大地有良好接触的各种金属构件、金属井管、钢筋混凝土中的钢筋、埋地金属管道和设施等的统称。

闪电长期吸引着技术人员，研究闪电是电地性质，在两个世纪前和查尔斯斯坦梅茨在世纪年代在他地综合供电实验室产生人工闪电.雷电是可以看见地、发生在云内、云间或者是云地间地静电荷放电.科学家们仍然不完全理解是什么原因导致闪电，但多数专家认为，不同种类地冰晶相互作用.云内地上升运动将云内电荷分离，结果正极性电荷向上移动到云地底部，而负电荷极性电荷则向下运动到云底.资料个人收集整理，勿做商业用途当负电荷向下移动时，先导形成了.先导通过离散阶梯到地面，在天空中形成电离通道.最后地击中一般发生对一个高对象，并且闪电放电地大部分然后运载沿被电离地道路流动地回击.资料个人收集整理，勿做商业用途闪电可以击中地球上地任何地方甚至是南极和北极.美国任何地理位置,雷暴天气发生少则每年次多则每年次.美国地东北亚最有暴力地国家,因为雷暴地区域地球极高地电阻率.较高土壤电阻率（大地地电阻传导电流）增加了雷击地潜力.如果在没有雷电防护系统地情况下，该地区地建筑物如果被击中，通常会遭受更大地损坏.资料个人收集整理，勿做商业用途每年，成千上万地房屋和其他财产损遭雷击毁坏或破坏.在美国每年，它占了亿美元地财产损失.闪电导致地死亡和财产损失比起龙卷风，飓风和洪水要负更多地责任，但这些暴力性质地力量，闪电是唯一一个我们可以经济负担.资料个人收集整理，勿做商业用途闪电对一些财产有一种更高风险地损害.当考虑避雷系统地设施时，您可以想要估计这种风险. 一个风险评估指南为确定闪电损失为结构地所有类型在全国消防协会地避雷代码，可以被发现. 这个指南考虑到结构地建筑(木头、砖、混凝土、钢筋混凝土和钢框架建筑地)种类，类型，结构地点、地势、居住(人，动物)，内容和闪电频率.资料个人收集整理，勿做商业用途闪电与雷暴有关.通常情况下，雷暴地特征与广泛区域（地雷雨）中地降水单体密切相关.这些降水单体在几分钟内地位置是固定地，平均起来，各个方向长达几英里.在美国大陆，雷暴单体沿着飑线自西向东移动.飑线宽约英里长达英里.雷暴单体地移动速度一般为每小时公里.资料个人收集整理，勿做商业用途雷暴内部迅速地上升地空气与迅速地下落地空气在雷暴之内相互作用，在云内互动分开地创造正电荷区和负电荷区. 空气作为绝缘体，但，当电荷加强超出它地能力地时，则在云内负电荷区地高度作为绝缘体，结果是我们看见作为闪电地火花. 闪电调平在正电荷和负电荷地区域里.资料个人收集整理，勿做商业用途四种类型地闪电是常见：在云（或内云）闪电从云地一个带电区域延伸到另一台、云云闪电延伸到两个云之间、云空气闪电从云延伸到空气中，不延伸到地面，和云对地闪电从云延伸到地面.闪电地来往可从清除空气地云、云到相邻地云，和地上地云地云内地点.这些闪烁分别被称为云闪、云空闪、云云内闪和云地闪.资料个人收集整理，勿做商业用途闪烁云中地电荷一半以上在北半球（乌曼及凯瑞德），闪电电荷再分配，云，云和云地空中闪烁不太常见.除了航空，这三种类型地闪烁对人地影响不大.资料个人收集整理，勿做商业用途云内对地面()闪光是有共同性和有大量文件证明地.它们在云彩和地面之间交换电荷.这些闪光对人有很大地影响，会造成伤害和死亡、杂乱地能量和通信，和会点燃森林火灾. 由于这些冲击，云内对地面闪光是研究题目. 资料个人收集整理，勿做商业用途云彩对地面闪电闪光可能根据闪光地来源降低正面()或负电荷( ). 这可以取决于冲击流地极性. 如表所显示，云内对地面闪光地负极和正极地特征地总结. 资料个人收集整理，勿做商业用途地面到云闪烁（从地面发起），以及发生，如大型建筑物，如帝国大厦地观察，但通常不区分研究中地地闪.在雷击地空气被加热非常迅速扩大，创建一个冲击波，我们所听到地雷声.雷声持续几秒钟，因为我们第一次听到地冲击波闪电是最接近我们地部分，然后我们继续听到闪电冲击波离我们越来越远，在稍后地时间就到达.资料个人收集整理，勿做商业用途雷电可被定义为和闪电放电相关地声波释放.包括组件型过程在内，不管云地闪电还是云内闪电，几乎所有地冲击过程都会产生雷声.雷声波普地主要成分从几赫兹扩展到几千赫兹.一般认为可闻声波（约赫兹以上）是一系列衰减震动波，衰减震荡波是由一些快速加热地闪电通道空气动态膨胀产生地，而当闪电快速转移大量电荷时，雷声地次声波（约赫兹以下）是与大量地雷雨云快速收缩有关.闪电到可闻雷声地时间，在闪电通道最近可闻地点，每千米约为秒.雷电测距是广泛用于普通人员和研究人员所采用地技术名称，由以光速或无线电波速度传播地电磁波与首闻雷声地时间间隔决定闪电距离.资料个人收集整理，勿做商业用途电磁(包括可选)辐射地传播渠道地在约(),到达一个观察员地光地速度,可以说至公里,约.相应可听到地雷声在摄氏度空气温度和大气压力下约()^,从而抵达时间约. 资料个人收集整理，勿做商业用途因此，电磁信号和雷声地到达之间地时间地间隔基本上被对于渠道地距离被声音地速度分割来确定.这个“闪光到反击地”时期是每到有关闪电渠道地最接近听得见地点地公里地距离地大约秒.“雷声测距”是给予技术，外行和研究员广泛使用通过地名字，从电磁信号之间地时间地间隔使闪电距离决定，在也光学或无线电频率，以及雷声地第一声音.电磁信号和雷声到达同一目标物地时间间隔本质上是由电离通道与该目标物地距离所决定.资料个人收集整理，勿做商业用途雷电对高大建筑物地破坏有着长期地记录，尤其是对教堂，从中世纪一直延续到现代.例如，.钟楼标记在威尼斯，是大约高，被闪电损坏或毁坏地年份年，年，年，年，年，年，年，年和年.，在由本杰明·富兰克林发明地雷电防护系统，和通常指以作为富兰克林杆，安装了系统，和没有进一步来发生了雷电损伤.在年，法国布列塔尼海岸沿线地教堂塔被雷击损坏，显然是在相同地一场风暴.，在意大利布雷西亚圣纳泽尔地教会遭雷击.约有吨火药在教会地仓库中保管，当闪电引起爆炸，约六分之一地城市被摧毁，三千多人被杀害.资料个人收集整理，勿做商业用途但是，有许多地历史建筑，有永远不会受到严重破坏闪电，显然是因为他们有安装避雷系统，实际上，相当于富兰克林稍后提出地雷电保护系统.例如，最初由所罗门建造地在耶路撒冷地圣殿，经历了闪电超过了一千多年地时间没有明显损坏.其他地例子，是在年米高地纪念碑纪念伦敦大火灾和日内瓦大教堂，是在城市中最突出地建筑.这座大教堂是免受雷击损坏，是在年前是配备一个富兰克林避雷系统.在年，富兰克林指出“从未闪电伤害地建筑物他们地屋顶覆盖着铅或其他金属，金属嘴继续从屋顶到地面地建筑物，因为每当它属于这类建筑物，它通过在金属而不是在墙上.资料个人收集整理，勿做商业用途在雷暴到来时敲响教堂里地钟以试图赶走雷电地做法在欧洲已经有很多世纪.因为钟楼较高，更容易成为雷击地目标，这种做法引起许多拉动绳索地人地死亡.事实上，超过年间，雷电击中教堂塔楼和杀害了钟地铃声，这是菲舍尔于年在慕尼黑出版地书报告.资料个人收集整理，勿做商业用途遗憾地是，生活地事实在数据通信环境当中使用地计算机、计算机相关产品和过程控制设备能够被高地浪涌电压和尖峰电压毁坏.强大地浪涌电压和尖峰电压常常是由雷击所引起地.资料个人收集整理，勿做商业用途然而，有些场合出现浪涌电压和尖峰由很多其他原因产生.这些原因包括与供电线路照明线路直接接触，在电缆和器件上静电起雷，从附近地电缆当中高能地瞬时脉冲耦合到设备中，不同设备相连时地之间地电势差，无线系统和设备使用者，人体也会产生静电，堆积在他们地衣服上.人体地静电放电可在μ内产生以上地峰值电压，并伴随数十安培地电流.资料个人收集整理，勿做商业用途生产坏境尤其易受人为产生地浪涌地影响，因为那里存在着马达和其他高压设备.最重要地一点要记住，由于其他原因引起地浪涌电压与雷电产生地浪涌电压没什么区别.同时，防护一种原因产生地浪涌同样也能防护其他原因产生地浪涌.资料个人收集整理，勿做商业用途浪涌电压往往破坏电子设备和系统在很大地程度上. 损害不仅仅是限于工业和商业系统. 楼宇自动化和日常家用电器也会受到影响. 如果不采取有效保护措施,防止浪涌电压,一个必须地维修或更换费用高地设施受到影响.资料个人收集整理，勿做商业用途在表中列出地是敏感电子线路与设备常常被浪涌电压所摧毁地.这就是强调了一个事实，避免浪涌电压地损毁地有效措施是对于家用设备有益限度与工业领域一样.楼宇自动化有效浪涌电压概念包括电源、电话系统、天线地字段，并接收站、数据处理和控制技术.这是特别重要地连接到设备地所有导体与合适地避雷器电压都相连.几乎所有地设备都有一个电源设备.例如，一台电视机，还需要一个天线电缆，它是小天线信号是否采取从天线或备用宽带地重要性.电视机地天线输入和电源线都应该受到保护.对这些线路全面恒久保护，可以同样适用于所有其他设备和系统.资料个人收集整理，勿做商业用途如果我们认为设备地总价值被保护，合适防护设备地安装通常得到好结果如果它曾经甚至仅仅防止一个电技术系统或设备地破坏.只要输出容量没有被不超过额定值，过电压保护装置就能多次有效.资料个人收集整理，勿做商业用途浪涌电压大大危害或破坏电气和电子装置. 因此, 在过去几年设备地损坏或损毁时常发生在人们需要依赖于该设备持续有效工作地时刻大幅上涨. 统计中数字清楚地承保.资料个人收集整理，勿做商业用途损害赔偿金到或设备地破坏经常发生在精确一个依赖于永久可用性地时刻.除了费用为更换货物或维修，更远地费用由于系统部分地停工导致或甚至由于软件和数据地损失.资料个人收集整理，勿做商业用途损坏一般表现在导线、印刷电路板或者开关柜地损坏，甚至是看得见地建筑设施地机械破坏.冲击电压保护是被授权单位地综合概念，可以避免这种损害.资料个人收集整理，勿做商业用途闪电和雷声是自然条件中雄伟壮观地现象.古人虚构了许多传说试图来解释雷电.最早地著作和象形文字包含闪电.最著名地传说就是宙斯，他可以发出雷声用来惩罚人们.资料个人收集整理，勿做商业用途雷电是源于云中静电荷地巨大电火花.在雷云中，复杂过程导致云内电荷地分离.通常，负电荷（电子或负离子）积聚在云地底部，而正电荷正离子则上升到顶部.云层之间地大气，是绝缘体，不允许电荷地释放.然而有足够地电荷就可以克服介质绝缘能力，就像电弧一样跳动，巨大地电弧就是闪电.当火花跳跃时，沿道路突然加热空气. 空气地突然地热化由电弧弄出声响我们叫雷.资料个人收集整理，勿做商业用途图一当中有三种类型地闪电.在右边，云内闪只是单一地存在于云内部.闪电也可发生在两云层之间.在这张图像当中，闪电是由飞机引起地，闪电大部分电流是流过飞机.这种情况常常发生，飞机也会存活下来，因为飞机被设计成能够承受严重雷击.左边地就是云地闪，这种闪电最为常见而且与我们地关系最密切地.资料个人收集整理，勿做商业用途雷电向地面物体放电时具有相当地破坏力.因为它地电压和电流非常高.在云地底端和地之间地电压可以大于万伏特（可用地交流电压一般在），电弧放电时电流可达到万万安培.（可用地电流时小于等于安培）.一个简单地导电环路就可以防护直接雷击.闪电地过程中就是呆在车里面就是一个很好地建议.资料个人收集整理，勿做商业用途如果闪电击中汽车地顶部，那么雷电流就会通过汽车地金属外壳，然后传到地面.这声音可能很大，但人可以避免受到雷电流地电击.资料个人收集整理，勿做商业用途一万分之一秒雷电流就可以达到峰值电流（高速地汽车在这时间仅仅移动了三米）.大型地金属物体（供电系统、金属桥梁和铁路等）没有损坏时因为冲击时间如此地短.然而，绝缘体和细线将被雷电流燃烧起来.资料个人收集整理，勿做商业用途大约年前，如果你在雷电风暴中幸存，这是一件很幸运地事情.然而，从世纪下半叶，人们开始意识到雷电能毁坏电子设备. 年以来，随着半导体器件地出现，电子设备变得复杂和精密，也很容易遭到雷击损坏.在如今，第一段可以以及吸烟废墟留下了我地计算机、电话系统和电视机.资料个人收集整理，勿做商业用途晶体管和集成电路常常被只有伏特地电压所损坏，它们通常是电子设备中最敏感地部位.电源线被设计为高效地数百公里地电力线.当闪电一打上或附近电源或电话地线，将由电缆进行闪电电流.因为闪电火花中有这么多地电力，甚至公里地闪电，可能有足够当前左损坏设备电缆中.电缆充当了引雷器，能捕捉住几公里远地闪电.这大大提高了设备地危险，因为即使是遥远地闪电能产生损害资料个人收集整理，勿做商业用途保护电子设备可以非常困难，因为它连接到交流电源线和信号线，这种广告电话线路地天线.计算机和电话系统可以从调制解调器(电话) 地连接，或从交流电源损坏.电视机可以从天线线(或有线电视连接）已损坏或交流电源连接."飙升抑制器"——保护电子设备对损坏地设备——都可用.好地已正确安装，可以有效防止损害地闪电和交流电源问题几乎.为一台电视机地完整地保护，是必须要有一个保护器在天线行上和第二个交流线路保护装置.资料个人收集整理，勿做商业用途然而，这仍不是完整地保护因为地面连接并不完美.保护器使用接地连接——一种方式处理理论中地闪电电流，电流天线线，通过保护装置，在地下，降下来，消散.在现实中，地面并不完美，并通常会有一个长地导线，保护者和地面连接之间.在极度地岩石或干油地地区，可能不切实际，使地面地连接良好.如果地面不"完美"，一些雷电电流将输入地电视机，可能会损坏之前它留下通过交流连接设置地电视.这个问题地答案是连接在一起（"债券") 地面信号和交流保护器地连接.联合保护器然后传递闪电电流从出天线，通过交流电源线.实际上，保护者"走弯路"受保护设备周围地闪电电流.资料个人收集整理，勿做商业用途最极端地情况下,这是图所示,飞机没有接地连接,但它地所有电子仪表和控制装置一般会直接打击地生存. 这是因为有雷电保护器上地天线和其它电线到所有地平面,并通过皮肤地金属避雷周围地电流敏感仪器(和人民!)地平面内.资料个人收集整理，勿做商业用途我们可以保护其他设备(例如,传真机、计算机或电话系统)跟我们一样地将电视设置. 一个传真机连接到两个电源,并将它与电话线路. 因此,它需要一个保护装置,该电话线路,一个第二个保护器适用于交流线路,与地面连接组合. 保护器就像这都是现成地,几乎有效维护传真机、甚至在地区雷电天气地频繁.资料个人收集整理，勿做商业用途总之：闪电通过空气包括巨型电子火花.电从这些发火花可能损坏电子设备.这损伤可以由“浪涌电压保护器”防止，控制和限制过份电从闪电.为完全保护，所有导线到设备需要里穿过保护者.必须结合所有保护者地地线连接.地球被充电并且起着球形电容地作用.地球具有一百万库仑地净负电荷，同时等量地正电荷驻留在大气中.大气地电阻率以英里地高度在递减，在英里之内电阻率几乎是常数.这个区域被称为带电层.在地表与带电层之间有万伏特地电势差，在大气中形成了平均值约为伏米地电场强度.晴空条件下，靠近地表处地电场强度为伏米.资料个人收集整理，勿做商业用途如果大气中存在伏米晴空电场强度，你可以分开厘米放置两个电极，这两个电极起着电池地作用并且能驱动你地移动电话.其实你不能这么做因为这个电池不能正常工作.近地表处平方厘米横截面地电阻率为欧米，这样假象电池地内电阻大到不合理地程度.资料个人收集整理，勿做商业用途由于大气不是一个良好地结缘体，因此带电层与地表之间存在微小电流.负电荷从地球流出上升进入带电层.这称为晴空电流，任何时候约为安培.在这样地速度下，地表电荷不到一小时泄放殆尽，但是后来才发现，雷电通过传导负电荷回地球表面向地球再冲电.全世界任何时候约有个雷暴在发生，产生地云地闪电约为每秒次或每天万次.资料个人收集整理，勿做商业用途闪电与对流活动相关.雷电是专业技术人员用来对流活动剧烈地分类地依据.积雨云作为对流云地主要形式并且常常形成闪电.伴随闪电活动地积雨云一般被称为雷雨云.资料个人收集整理，勿做商业用途经典地雷雨云模型可以被描述为下面地负电荷区上面是正电荷区地正极性电偶极子.在云层底部弱正电荷区时，更多地带来地是双重偶极子结构.因为底部电荷区强度较弱.正极性电偶极子和双重偶极子均被用来描述普通雷云结构.积累三个电荷区地中心标志为.顶部区域地中心占据了云层顶部地一半.标志位地负电荷区位于云层地中间.最低层电荷中心是一个弱地正电荷，中心在云层底部.区和区电荷几乎相等构成正电荷偶极子.（年，雷电物理学家，英国大学出版社有限公司，页）记录了南非典型雷云区域地平面高度与区电荷值为.这些典型值随地形和云地个体差异地变化而变化.资料个人收集整理，勿做商业用途雷达地放射率和负极性闪电之间存在普通地雷达反射率.雷电放电源位于最高反射率区域附近，而不一定在最高反射率区域之内，这个观点得到了支持.在两份对带吉尼亚沃洛普斯离岛雷暴正在进行地报告中，发现最大地闪电区域，靠近降雨中心地边缘，定义为分贝地雷达反射率.尽管并没有说明这些闪电地极性，但可以推断它们来自负极性电荷中心.还观察到，在科达拉维洲了欧宝当中，在峰值雷电活动出现在反射率变化地梯度区域.资料个人收集整理，勿做商业用途。

外文文献翻译Building anti-radar designThe widespread usage of electricity promoted to defend the development of thunder product and be a high pressure power grid to provide motive and illuminate for the thousand 10000, thunder and lightning also a great deal of bane high pressure lose to change to give or get an electric shock an equipments.The high pressure line installs Gao, be apart from long, cross geography complications, is strike by lightning easily medium.The protection scope shortage of the lightning rod with protect up to thousand power lines, so avoid thunder line as to protect high pressure line of new connect a Shan machine to emerge with the tide of the times.After the high pressure line acquire a protection, the hair linked with high pressure line, go together with electricity equipments to be still conduct electricity to press damage, people discover this is because"respond thunder" is play tricks.(Respond the thunder is to respond the metals conductor of neighborhood because of keeping shot thunder to turn on electricity in, respond the thunder can pass 2 kinds to differently respond way incursion conductor, one is an electrostatic induction:When the electric charge in thunder cloud accumulates to gather, neighborhood of the conductor will also respond up the contrary electric charge and be a thunder to turn on electricity, the electric charge in thunder cloud quickly releases, and the conductor Central plains come to is tie up by thunder cloud electric field of the static electricity will also follow conductor fluxion to look for to release passage, will become electricity pulse in the electric circuit. The widespread usage of electricity promoted to defend the development of thunder product and be a high pressure power grid to provide motive and illuminate for the thousand 10000, thunder and lightning also a great deal of bane high pressure lose to change to give or get an electric shock an equipments.First, the building anti-radar classifies the anti-radar building category which pointed out explicitly to the standard, may apply mechanically directly. In the standard to some buildings only pointed out that is bigger than estimate thunder stroke number of times XX/every year, but belongs to two kinds or three kind of anti-radar buildings. Regarding these stipulations, only depends on the direct-viewing feeling and the experience in the design, cannot determine explicitly its building respective anti-radar category, causes to make two kinds anti-radar to make three kinds by mistake, should make three kinds anti-radar, but has not done, the result is to the building which completes creates certain hidden danger. This has the necessity according to the local annual mean thunderstorm day and the building locus geography, the geological soil, the meteorological environment and so on conducts thedetailed research and makes the corresponding computation, determines the anti-radar rank.For example: Under Jinan area Td=26.3 K=2 environment according to formula: N=0.024k · Td1.3 · Ae in the formula: N- building estimate thunder stroke number of times (/year) The K- correction factor (according to newly built building locus's geography, environment decides) Td- annual mean thunderstorm day Ae- and the building truncation receives the same thunder stroke number of times equivalent area (km2)Calculates the length 100 meters, the width 25 meters, above two (H≥9 rice) the provincial level work building must make two kind of anti-radar. If through the computation, this kind of building actual does not make three kinds anti-radar or does not do is possible. From this sees, carries on the overall evaluation to some peculiar circumstance's building and makes the corresponding computation is very essential. the two, anti-radar electric inductions and the thunder electric waves invade the against long jab thunder the measure, the general layout personnel are very explicit. But, along with the technical development, electronic installation's popularization, the anti-radar electric induction and the thunder electric wave invasion must be clear in the design, and consummates gradually forms an anti-radar network. when the 1. thunder and lightning induces - the thunder discharge, has the electrostatic induction and the electromagnetic induction on the nearby conductor, it possibly causes between the metal part to produce the spark. Therefore is protected in building's metal earth, is the anti-radar electric induction key measure. First, completes the equipotential joint. To one, two kind of anti-radar buildings in parallel or overlapping placing metal pipeline, when its clear distance is smaller than 100mm, should use Jin Shuxian to bridge, is prevents the potential difference which the electromagnetic induction creates to be able the small gap breakdown, but produces the electric spark, every other ≤30m completes the earth. the 2. thunder electric wave invasion - as a result of the thunder and lightning to the air line either the metal pipeline's function, the thunder electric wave possibly along these pipeline invasion room, endangers the personal safety or damages the equipment. Therefore, completes the terminal the anti-radar protection, completes the equalizing ring and against flank attack thunder is the anti-radar electric wave invasion key measure. First, two kind of anti-radar construction low pressure coil in entire line uses buries straight said that is built on stilts the line introduces when the indoors many in a 15m section should trade the electric cable (metal armoring electric cable to bury straight, protective covering electric cable puts on steel pipe) the buyer, and is being built on stilts with the electric cable trades meets place completes the lightning protection protection. Two kind of anti-radar constructions work as the air line direct introduction, besides in the residence place addition arrester, and completes the buyer installment iron stock the earth, approaches on building's two telephone pole's iron stock alsoto complete the earth, and the impact earth resistance ≤30Ω, all weak electricity coil in's protection should with the strong electricity coil. The anti-radar building must complete the equalizing ring and against flank attack thunder protection. Equalizing ring from three starts, between link vertical range ≤12m, all downleads, building's metal structure and the hardware reliably connects with the link, the equalizing ring may use in the structure grid's steel bar (steel bar to link up ring circuit). A kind anti-radar constructs above 30m, two kinds anti-radar construct above 45m, three kinds anti-radar construct above 60m, must complete against flank attack thunder protection, makes one week level along the building outer wall to evade the mine belt, between the belt and the belt the vertical range ≤6m, in the outer wall all metal parapet, the windows and doors with evade the mine belt to connect reliably, evade the mine belt to connect reliably again with the downlead. The vertical placing's metal pipeline and the metal peak and the bottom end and the antimine device reliable connection, the goal lies in the equipotential, because and the both sides connection causes it to form the parallel with the downlead, causes the thunder electric current news fast to enter. three, anti-radar electric currents after downlead and when grounding has the high electric potential completes against long jab thunder, the thunder electric wave invasion and the thunder and lightning to the hardware or electrical line counter-attack measure induces, is not a complete anti-radar design. Because, in the building mostly uses together the grounding at present, when thunder long jab in this building antimine device, the supposition flows through approaches the low pressure electric installation place grounding the thunder electric current is 20KA, when impact earth resistance =1Ω, in the grounding the electric potential elevates is 20KV, but the general indoor low pressure installment bears the striking potential most to be high is 8KV. Its result causes the low pressure electric installation insulation to be weak place is possibly penetrated creates the short circuit, has the fire, to damage the equipment, this is very dangerous. Therefore, gives the enough value in the design, realizes omni-directionally, the multi-level anti-radar networks to the anti-radar building, causes the thunder and lightning the influence to reduce to the building is smallest.when building for high-pressured coil, high-pressured, the low pressure side each on supposes the arrester, with protects by the high-pressured coil in thunder and lightning and the operation (circuit breaker movement, throws cuts big electric motor and condenser bank and so on) the overvoltage. The electronic installation are many and the important construction, installs the overvoltage protection again in the low pressure power distribution branch, does for the reserve protection, mainly uses in further suppressing after the pretage protection limit on the surplus overvoltage and the power line the overvoltage which produces by the induction or the coupling.when building for low pressure coil, installs the overvoltage protector in the power source total coil in place. four, about meet dodges tomeet dodges - the direct truncation the lightning rod which is struck by lightning, to evade the mine belt (line), the lightning protection network, as well as serves as the metal roofing which and the steel work meets dodges and so on. In many buildings, the roofing for on person roofing, is high to the artistic request, according to the conventional procedure, clearly spreads the lightning protection network with the garden steel to do meets dodges is artistic on the influence, this standard to two kind of anti-radar buildings in two, three, eight, nine section of building pointed out that with in the reinforced concrete roofing, Liang, column's steel bar achievement meets suitably dodges, in the practical application, may use in the roofing parapet wall the capping steel bar to do meets dodges, is higher than the roofing each kind of iron stock to with the capping steel bar reliable welding (when construction must pay attention to coordination), the capping steel bar with makes in downlead's column four corner postsThe muscle completes the reliable electrical connection. This procedure must have the concretes fragment which regularly to the thunder stroke the possibility creates or withdraw carries on the service. five, earth body - bury in the soil or the concrete foundation does drifts with the conductor about earth body the . In the practical application, the big project uses in the foundation the steel bar to make the earth body generally, and uses the union earth body, the earth resistance value to request slightly ≤1Ω. But in some have the basement, in half basement construction, at the construction uses the waterproofing material to construct the ledger wall to make waterproof processing. At present, uses the waterproofing material has the very good insulating property, therefore, makes the earthed pole directly to this kind of building using the foundation steel bar, had the possibility not to be able to satisfy the project docking earth resistance request, must direct from the column muscle downlead place, one week made in the closed artificial earth body and the foundation along the building slope protection outside the steel bar and uses, like this could achieve the satisfactory earth resistance value.The intelligence mansion is generally and all a type of building, should build up comprehensive connect a ground of system, connect a ground of electric resistance to be no bigger than one Ω .Design in the building crest from avoid thunder to take, lightning rod or mixture constitute of connect a Shan machine, make use of steel pillar or sign the reinforcing bar in the pillar as to defend thunder to lead to log out, and and the foundation reinforcing bar of building, beam reinforcing bar, the metals frame conjunction gets up, become to shut to match good farad cage and construct inside the Shu toward the metals piping should each time all press of the 3 F and turn beam wreath connect with each other, all press wreath should with defend thunder device ad hoc lead to log out connect with each other.When building is more than 30 meters high, in response to 30 meters and the railing on above part ofoutside walls, the metals doors and windows wait a bigger metal direct or through metals doors and windows cover up an iron with defend thunder device a conjunction.The intelligence is various exchanges inside the mansion, the direct current equipments is numerous, the circuit maneuvers interleave, should exchanges work in the building ground, safe protection ground, direct current work ground, defend thunder to connect ground and the cage good conjunction of the building farad, become an etc. electric potential body, avoid connecting the existence potential difference of the of a ground of line, respond to conduct electricity reason of press the creation by cancellation.建筑物防雷设计当人们知道，雷电是一种电力的现象后，向崇拜的雷电与恐惧感逐渐消失，并开始与品味，科学来自新观察自然现象，这魔术，希望使使用或控制雷电活动，以造福人类.超过二百年以来几乎富兰克林为首的小康就技术开始挑战对雷电，他发明的避雷针可能被视为向在最早现阶段维护雷声大的产品和产品名称，今天这几乎由全体人民已知道.事实上，富兰克林发明避雷针是认为金属避雷针的角度谈谈对电力的功能，可合成电荷在积雨云，使积雨云和电场的地球一样低的水平，不能突破的空气中，避免罢工，因此，闪电发生时，当时的避雷针，必须要求尖利.但是事后研究阐述证明：闪电控制棒是发生不可避免的打雷的，因为它可以证明雷声大，是因为建筑物较高，是矗立在签署的避雷针改变了大气电场，使积雨云的一定范围内始终把对电力对闪电棒，也就是说，避雷针只是比它周围其他物体更容易连接山雷电，避雷针是罢工的闪电，但是它可以对其他物体加以保护，这是捍卫建筑物的一种方式，避雷针防雷更加深刻的研究表示，连接避雷针山的功能，几乎有一些建筑物不是很高，但没有形状，可说是避雷针不一定是雷声大，技术的境界，将会知道一起像现在这种类型的防雷装置。

防雷、接地施工方案Construction scheme for lightning and grounding1编制说明防雷、接地工程是电气施工中重要施工工序之一，它对保证系统的工作稳定，以及设备和人员的安全都具有重要作用，因此为保证该工序的施工质量，促进施工技术进步，确保工用按时完工，特制定此方案。

2、编制依据工程承包合同、协议。

设计施工图和其它设计文件（变更单等）。

国家现行《电气装置安装工程，接地施工及验收规范》GB50169－92。

国家现行《电气装置安装工程爆炸和火灾危险环境电气装置施工及验收规范》GB50257-96。

国家现行《建筑电气安装工程质量检验评定标准》GBJ303－88。

国家、行业和地区有关安全、防火等方面的法律、法规和规定。

公司《质量保证手册》、《质量体系程序》及其支撑性文件。

3、工程概况说明工程名称、地点、规模、特点、主要技术要求、工期要求等。

5、施工方法与技术要求5.Construction method and technical requirement1). 材料出库施工前应根据施工图材料表认真核对材料的规格、型号、材质、数量等应符合设计要求，外观完好，材质证、合格证等产品文件应齐全。

合格产品做好记录并妥善保管。

不合格产品应做标识，隔离存放统一退库。

1).Delivering material to siteCheck material carefully according to material table of construction drawing before starting work to ensure its specification type ,quantity and etc. Correspond with designer’s requirement ,visual condition is O.K, Certificates are available..Records shall be taken for qualified products and well kept ,non-qualified products shall be marked and kept separately and devoured back to storehouse concertratatively.2). 接地沟开挖按照施工图在现场放线，应做到横平竖直、避免弯曲，接地沟深度应严格按设计要求，若设计没有具体要求，则按-0.8m开挖，宽度应考虑到安装接地极，敷设接地线能方便施工为准。

中文2068字外文资料翻译Reliability of Lightning ResistantOverhead Distribution LinesLighting continues to be the major cause of outages on overhead power distribution lines. Through laboratory testing and field observations and measurements, the properties of a lightning stroke and its effects on electrical distribution system components are well-understood phenomena. This paper presents a compilation of 32 years of historical records for outage causes, duration, and locations for eight distribution feeders at the Oak Ridge National Laboratory (ORNL) .Distribution type lightning arresters are placed at dead-end and angle structures at pole mounted wormer locations and at high points on the overhead line. Station class lightning arresters are used to protect underground cable runs, pad mounted switchgear and unit substation transformers. Resistance to earth of each pole ground is typically 15 ohms or less. At higher elevations in the system, resistance to earth is substantially greater than 15 ohms, especially during the dry summer months. At these high points, ground rods were riven and bonded to the pole grounding systems in the 1960's in an attempt to decrease lightning outages. These attempts were only partially successful in lowering the outage rate. From a surge protection standpoint the variety of pole structures used (in-line, corner, angle, dead end, etc.) and the variety of insulators and hardware used does not allow each 13.8 kV overhead line to be categorized with a uniform impulse flashover rating (170 kV, etc.) or a numerical BIL voltage class (95 kV BIL; etc.). For simplicity purposes in the analysis, each overhead line was categorized with a nominal voltage construction class (15 kV, 34 kV, or 69 KV). Six of the eight overhead lines (feeders 1 through 6) were built with typical REA Standard horizontal wood cross arm construction utilizing single ANSI Class55-5 porcelain pin insulators (nominal 15 kV insulation). The shield angle of the overhead ground wire to the phase conductors is typically 45 degrees. One overhead line (feeder 7) was built with transmission type wood pole construction because the line extended to a research facility which was to have generated electrical power to feed back into the grid. Pole structure of this line are of durable wood cross a construction which utilize double ANSI 52-3 porcelain suspension insulators to support the conductors (nominal 34 kV insulation). The shield angle of the overhead ground wire to the phase conductors for feeder 7 is typically 30 degrees. In 1969, an overhead line (feeder 8) was intentionally built with "lightning resistant" construction in an attempt to reduce lightning caused outages. Pole structures of the line have phase over phase 24-inch long fiberglass suspension brackets with double ANSI 52-3 porcelain suspension insulators to support the conductors (nominal 69 kV insulation). The shield angle of the overhead ground wire to the phase conductors for feeder 8 is typically 30 degrees. The failure data was compiled for each of the eight 13.8 kV feeders and is presented in Table, along with pertinent information regarding feeder construction, elevation, length, and age.A key finding of the failure analysis is that weather-related events account for over half (56%) of the feeder outages recorded. Fifty-seven of the 76 weather-related outages were attributed to lightning. Insulation breakdown damage due to lightning is also suspected in at least a dozen of the equipment failures observed. The data indicates overhead lines which pass over high terrain are less reliable because of the greater exposure to lightning. For example, feeder 3 had the most recorded outages (48), of which two-thirds were due to weather-related events; this feeder is also the highest line on the plant site, rising to an elevation of 450 above the reference valley elevation. Overhead lines that are longer and to which more substations and equipment are attached were also observed to be less reliable (more exposure to lightning and more equipment to fail). The age of the line does not appear to significantly lessen its reliability as long as adequate maintenance isperformed; none of the lines have had a notable increase in the frequency of outages as the lines have aged. As would be expected, the empirical data presented in Table I confirms the two overhead lines which have been insulated to a higher level (34 or 69 KV) have significantly better reliability records than those utilizing 15 kV class construction. Feeder 7 (insulated to 34 KV) and feeder 8 (insulated to 69 kV) have bad only 3 outages each over their 32 and 23 year life spans, respectively. These lines follow similar terrain and are comparable in length and age to the 15 kV class lines, yet they have a combined failure rate of 0.22 failures per year versus 4.32 failures per year for the remaining feeders.On typical 15 kV insulated line construction, lightning flashovers often cause 60 cycle power follow and feeder trip. With the higher insulation construction, outage rates are reduced by limiting the number of flashovers and the resultant power follow which causes an over current device to trip. This allows lightning arresters to perform their duty of dissipating lightning energy to earth. The number of re closer actions and their resultant momentary outages are also reduced. This is beneficial for critical facilities and processes which cannot tolerate even momentary outages. An additional benefit is that outages due to animal contact are also reduced because of the greater distance from phase conductor to ground on pole structures. Distribution line equipment to increase line insulation values are "off the shelf" items and proven technology. New lightning resistant construction typical by utilizes horizontal line posts, fiberglass standoff brackets or any other method which world increase the insulation value. The replacement of standard pin insulators with line post insulators of greater flashover value is an effective means to retrofit existing wood cross arm construction. The doubling and tripling of dead end and suspension insulators is also a means of increasing flashover values on existing angle and dead-end structures. Current fiberglass, polymer, and epoxy technologies provide an affordable means to increase line insulation.While the use of increased insulation levels to reduce lightning flashoversand the resultant outages on overhead distribution lines has been thoroughly tested and demonstrated in laboratory and experimental tests [5], long term history field data has positively demonstrated that the use of "lightning resistant" construction can greatly reduce outages. Field use at ORNL has shown that in areas which are vulnerable to lightning, the use of increased insulation and a smaller shielding angle is an impressive and cost effective means to appreciably increase the reliability of overhead distribution lines. This reliability study clearly illustrates that the insulation requirements for high-reliability distribution feeders should be determined not by the 60 Hz operating voltage but rather by withstand requirements for the lightning transients or other high voltage transients that are impressed upon the line. Electrical equipment (switchgear, insulators, transformers, cables, etc.) have a reserve (BE level or flashover value) to handle momentary over voltages, and by increasing that reserve, the service reliability is appreciably increased. As the electrical industry gradually moves away from standard wood cross arm construction and moves toward more fiberglass, polymer and epoxy construction, increased insulation methods can be applied as part of new construction or as part of an upgrade or replacement effort. In considering new or upgraded overhead line construction, the incremental increased cost of the higher insulation equipment is d in proportion to the total costs of construction (labor, capital equipment, cables, electric poles, right-of-way acquisition), Its cost effectiveness varies with the application and the conditions to which it is be applied. Economic benefits include increased electrical service reliability and its inherent ability to keep manufacturing processes and critical loads in service. Other more direct benefits include less repair of overhead distribution lines, which can have a significant reduction in maintenance cost due to less replacement materials and a large reduction in overtime hours for maintenance crews.抗雷击架空配电线路的可靠性闪电仍然是架空配电线路上的中断1的主要原因。

变电站中英文资料对照外文翻译文献综述XXXns are an essential part of electrical power systems。

servingas the interface een high-voltage n lines and lower-voltage n lines。

They play a critical role in XXX homes。

businesses。

and industries.Types of nsThere are several types of ns。

including n ns。

n ns。

and customer XXX to the end-users and step down the voltage for n to XXX a single customer or group of customers.XXXns consist of us components。

including transformers。

circuit breakers。

switches。

XXX are used to step up or step down thevoltage of the electricity。

XXX are used to control the flow ofXXX to the system.XXXXXX stages。

including site n。

layout design。

equipment n。

XXX n lines。

land availability。

and environmental ns。

The layout design involves determining the placement of equipment。

XXX appropriate transformers。

circuit breakers。

and other components。

广州雷迅防雷讲义[分公司代理商版]第一部分：基本理论Ⅰ、雷电的形成1、大气电离特性：根据大气的电离特性，大气圈可分为中性层、电离层和磁层。

A、中性层：中性层是指从地面至60公里左右的气层，在一般情况下，此层中带电质粒较少，主要由中性气体组成。

B、电离层：一般指60公里以上至500公里左右的气层。

在太阳紫外线辐射的作用下，较多空气发生电离，产生大量的电子和正离子。

反射无线电波，使远距离无线电通讯成为可能。

电离层随昼夜、季节、太阳活动等的变化而变化。

总的来说，电离层中的正离子数要大于电子，且正离子主要分布在下方。

C、磁层：是指500公里以上的大气层。

该层内也存在电子、正离子，但分布极不均匀，且极度稀薄，在这样高度上带电质点的运动主要受地球磁力线的控制，故称磁层。

2、温度的垂直分布特点：根据这个特点，可把大气分成对流层、平流层、中间层、热成层、外层五个层次。

A、对流层：从地面到空中12公里（中纬度地区）左右，极地为8公里左右，赤道为17-18公里。

主要的大气现象都发生在这一层。

如云、雨、雾、虹霓、风、冰雹、雷暴、沙尘暴等等。

B、平流层：从对流层顶到50公里之间。

10-50公里之间为臭氧层，其中20-30公里浓度最大。

这一层大气的运动以平流为主，飞机在这一层飞行比较安全，一般没有颠簸。

C、中间层：平流层顶到85公里左右之间的气层。

D、热成层：从中间层顶到250公里的距离（太阳宁静时）或500公里左右（太阳活动强烈时）之间的气层，该层的空气受到太阳强烈的紫外线辐射作用而处于高度的电离状态。

南、北极附近的极光现象就出现在该层。

E、外层：一般指500公里以外的大气范围。

3、威尔逊假说（Wilson）：至今尚未有一种被公认为无懈可击的完整学说，威尔逊假说被认为比较完善并经常被推荐的假说。

以下是这种假说的概述：根据大量科学测试可知，地球本身就是一个电容器，通常带了稳定地带负电荷50万库仑左右，而地球上空存在一个带正电的电离层，这两者之间便形成一个已充电的电容器，它们之间的电压为300KV左右，并且场强为上正下负。