斯坦福 马拉松 西门子 英格 利莱松玛 法拉弟 科私 威克 三波 ABB发电机电球维修保养维修
马拉松运动医疗支援
Marathon runner injury
• 波士顿遵循高门槛:惟一需要以往成绩 纪录达标才可以参加 • 巴黎马拉松也对参赛选手有着严格的 入门的标准，必须需要提供20公里长 跑成绩证明才允许参加。 • 东京马拉松0死亡(2007-):42名医生，70 名护士，420名专业救护成员，40名跑 者+医生。还有在日本机场、地铁站 等 公共场所都配备自动除颤器（AED）， 在一些高风险体育比赛中被强制性应 用，甚至都写进了某些法规。赛道配 备66台AED设备，15救护站，并配备紧 急救助车辆，而医疗服务专业救护体 系在过去几年用AED救过3个参赛者的 性命。
近年来猝死事件回顾
• • ●2015年，首次参加渣打马拉松十公里赛事的24岁男子在距离终点仅几百米的铜锣湾怡东酒店时倒地，最 终不治。 ●2014年，珠海半程马拉松中特种兵猝死。苏州环金鸡湖国际半程马拉松，一位25岁女选手在比赛过程中 死亡。 21岁的小伙子倒在了昆明高原国际半程马拉松赛的赛道上。张家口· 康保草原国际马拉松赛中，一名 选手在半程赛道约18公里处死亡。新北市一名45岁周姓男子，台湾米仓田中马拉松。（全国各地一共51场 ，平均一个月4场） ●2013年，美国波士顿于4月15日举行第117届波士顿马拉松大赛（爆炸事件致3人死）。英国南部海岸度假 胜地布莱顿举办的马拉松赛上，1名23岁男子倒地身亡，疑似是心脏病发。墨西哥首都举行的国际马拉松比 赛中,一名38岁的选手因呼吸衰竭死亡。 ●2012年，11月18日，广州首次举办马拉松比赛。在第16届香港国际马拉松赛上，一名男选手在完成比赛 后晕倒，送医院后被证实死亡。同年在英国伦敦国际马拉松赛上，一名30岁的女子在离终点不到1公里处晕 倒，后经抢救无效不幸去世。 ●2011年，在美国费城举办的马拉松比赛上，两名参赛者因心脏病突发死亡，其中一名21岁亚裔男子在终 点倒下，另一名40岁的白人男子在距离终点线400米处倒下。二人均被送往附近医院，随后医生宣布两人因 心脏病突发死亡。加拿大多伦多湖滨马拉松赛 1人猝死。 ●2010年，美国圣地亚哥“银滩半马拉松公开赛”，32岁的华裔参赛者在跑到离终点不到1公里处突然倒地 ，陷入昏迷，送医院抢救无效宣告死亡。 ●2009年，底特律进行的第32届马拉松比赛3名参赛者在比赛中突然死亡。 ●2008年，上海国际马拉松赛成为马拉松爱好者一显身手的机会，轰轰烈烈的比赛后，却传来噩耗：华东 理工大学法学院一名研究生在参加半程马拉松比赛时突然倒地，后抢救无效身亡。 ●2007年，28岁的美国马拉松赛冠军莱恩谢伊猝死在美国纽约马拉松赛上。 ●2006年，共有4万人参加的香港国际马拉松赛造成了1人死亡，22人入院以及4800人抽筋的现象。 ●2005年，北京马拉松赛上，一名26岁的业余选手不幸猝死。 ●2004年，北京马拉松赛上，一名24岁的大学生和一名64岁的长跑俱乐部联队队员猝死。
迎亚运常用100英语
迎亚运常用100英语n Games 亚洲运动会2.host country 举办国3.opening ceremony 开幕式4.closing ceremony 闭幕式5.torch relay 火炬传递6.mascot 吉祥物7.volunteers 志愿者8.sports events 体育赛事9.track and field 田径10.swimming 游泳11.gymnastics 体操12.diving 跳水13.table tennis 乒乓球14.badminton 羽毛球15.football 足球16.basketball 篮球17.volleyball 排球18.archery 射箭19.boxing 拳击20.taekwondo 跆拳道21.judo 柔道22.wrestling 摔跤23.tennis 网球24.hockey 曲棍球25.shooting 射击26.weightlifting 举重27.rowing 划船28.canoeing 皮划艇29.cycling 自行车赛30.triathlon 三项全能31.equestrian 马术32.fencing 击剑33.chess 国际象棋34.bridge 桥牌n record 亚洲纪录36.world record 世界纪录37.gold medal 金牌38.silver medal 银牌39.bronze medal 铜牌40.podium 前三名41.final round 决赛42.semi-final 半决赛43.preliminary round 预赛44.qualification round 资格赛45.heat race 预赛（径赛）46.knockout round 淘汰赛47.referee 裁判员48.linesman/judge 裁判员（田赛）49.scorekeeper/timekeeper 计分员/计时员50.official 官员（组织者）51.VIP guest 要客（贵宾）52.cheerleader 啦啦队长53.stadium/arena/sports ground/pitch体育场/体育馆/场地/草坪球场）n Games Federation 亚洲运动会联合会n Games Organizing Committee 亚洲运动会组织委员会56.host city 举办城市57.torchbearer 火炬手n Games mascot 亚运会吉祥物n Games emblem 亚运会会徽n Games flag 亚运会会旗n Games theme song 亚运会主题歌n Games torch 亚运会火炬n Games Volunteer Program 亚运会志愿者计划64.athlete’s village 运动员村65.international observer 国际观察员66.local organizer 当地组织者n Games media center 亚运会媒体中心68.television rights 电视转播权69.official sponsor 官方赞助商70.official supplier 官方供应商71.event coordinator 活动协调员72.accreditation center 资格认证中心73.ticketing system 票务系统74.security and safety 安全保障75.press conference 新闻发布会76.media coverage 媒体报道77.live broadcast 直播 commentary 电视评论79.live streaming 直播流媒体80.official website 官方网站81.social media 社交媒体82.hashtag话题标签83.medal tally 奖牌榜84.host city bid 申办城市85.bid presentation 申办陈述报告86.host city evaluation 申办城市评估87.host city selection 申办城市选拔88.bid committee 申办委员会89.bid logo 申办标志90.bid book 申办报告91.bid video 申办视频n Games Torch Relay Route 亚运会火炬传递路线93.torch relay route map 火炬传递路线图94.torch relay start and end point 火炬传递起点和终点95.torch relay stopover points 火炬传递停靠点96.torch relay schedule 火炬传递时间表97.torch relay parade route 火炬传递游行路线98.torch relay iconic landmarks 火炬传递标志性地点99.torch relay partners 火炬传递合作伙伴100.torch relay volunteers 火炬传递志愿者。
运动比赛主要项目英语名称
运动比赛主要项目英语名称编辑：理想谭一、田径项目（Track and Field）1. Sprint（短跑）：Short-distance running races.（短距离跑步比赛。
）- 100-meter dash（100 米短跑）- 200-meter dash（200 米短跑）2. Middle-distance running（中距离跑）：Races of moderate distances.（中等距离的跑步比赛。
）- 800-meter run（800 米跑）- 1500-meter run（1500 米跑）3. Long-distance running（长跑）：Long-distance races.（长距离跑步比赛。
）- 5000-meter run（5000 米跑）- 10000-meter run（10000 米跑）4. Hurdles（跨栏）：Races with barriers to jump over.（有栏架需要跨越的比赛。
）- 110-meter hurdles（男子110 米栏）- 100-meter hurdles（女子100 米栏）5. Relay races（接力赛）：Races where teams pass a baton.（团队传递接力棒的比赛。
）- 4x100-meter relay（4×100 米接力）- 4x400-meter relay（4×400 米接力）6. Long jump（跳远）：Jumping for distance.（比跳跃距离的项目。
）7. Triple jump（三级跳远）：Three consecutive jumps for distance.（连续三次跳跃比距离的项目。
）8. High jump（跳高）：Jumping over a bar for height.（比跳跃高度，越过横杆的项目。
世界顶级马拉松赛事盘点
世界顶级马拉松赛事盘点（正文）世界顶级马拉松赛事盘点马拉松是一项具有悠久历史和广泛影响力的长跑项目，而世界顶级马拉松赛事更是吸引了众多选手和观众的关注。
在这篇文章中，我们将盘点一些世界顶级马拉松赛事，让读者对这个精彩的运动有更深入的了解。
1. 波士顿马拉松波士顿马拉松作为世界上最古老的、历史最悠久的马拉松赛事之一，吸引了来自全球各地的马拉松爱好者争相参与。
该赛事创办于1897年，以其具有挑战性的赛道和激烈的竞争而闻名。
波士顿马拉松每年四月举行，赛道全长42.195公里，起点位于波士顿郊区霍普金顿，终点设在波士顿市中心的卡波利广场。
这个赛事不仅吸引了顶级选手的参与，还成为了体育界的一项盛事。
2. 伦敦马拉松伦敦马拉松是全球最大的慈善马拉松赛事之一，也是世界田径协会金牌等级比赛。
该赛事创办于1981年，自那以后每年四月在伦敦市举行。
伦敦马拉松的赛道贯穿了伦敦市内的重要地标，如伦敦塔桥、大本钟和白金汉宫等。
这项赛事吸引了世界各地的选手和观众，同时也成为了众多慈善机构筹款的重要途径。
3. 芝加哥马拉松芝加哥马拉松是美国规模最大的马拉松赛事之一，拥有超过40,000名参赛选手。
该赛事创办于1977年，每年十月在芝加哥市举行。
赛道设在市区内，穿越了一些著名的景点和社区，如密歇根湖畔、芝加哥大学和米尔沃基大道等。
芝加哥马拉松以其快速的赛道而受到选手的青睐，是创造个人最好成绩的理想选择之一。
4. 柏林马拉松柏林马拉松是世界顶级马拉松赛事之一，也是马拉松世界纪录频繁被打破的地方。
该赛事创办于1974年，每年九月在柏林市举行。
柏林马拉松赛道平坦且快速，被认为是刷新世界纪录的理想地点。
多次世界纪录在柏林马拉松上诞生，如2018年肯尼亚选手凯普乔格打破男子纪录和2019年埃塞俄比亚选手齐里内西亚打破女子纪录。
5. 纽约马拉松纽约马拉松是世界马拉松大满贯赛事之一，以其宏伟的赛道和独特的场景而著名。
该赛事创办于1970年，每年在纽约市举行。
电机学符号及读音
电机学符号及读音
电机学符号及读音包括：
1. 西格玛 Sigma，读音为西格马。
2. 阿尔法 Alpha，读音为英语at的简写，英语念爱特。
3. 贝塔 Beta，读音为西格玛 Sigma。
4. 伽玛 Gamma，读音为套 Tau。
5. 德尔塔 Delte，读音为德尔塔 Delte。
6. 宇普西龙 Upsilon，读音为艾普西龙 Epsilon。
7. 艾欧塔 Iota，读音为艾欧塔 Iota。
8. 克西 Xi，读音为克西 Xi。
9. 喀帕 Kappa，读音为喀帕 Kappa。
10. 欧麦克轮 Omicron，读音为欧麦克轮 Omicron。
11. 拉姆达 Lambda，读音为拉姆达 Lambda。
12. 派 Pi，读音为派 Pi。
13. 缪 Mu，读音为缪 Mu。
14. 柔 Rho，读音为柔 Rho。
15. 拗 Nu，读音为拗 Nu。
16. 电动机常用符号 KVYJ KVPZYA等读法
- KV (千伏)，K(千) V(伏)，意为电压继电器；
- KYJ (千压继电器)，K(千) YJ(压继电器)；
- KA (千安)，K(千) A(安)，意为电流继电器；
- LJ (拉继电器)，L(拉) J(继电器)；
- FLJ (负序电流继电器)，F(负) LJ(流继电器)；- LLJ (零序电流继电器)，L(零) LJ(流继电器)；- ZYJ (正序电压继电器)，Z(正) YJ(压继电器)；- FYJ (负序电压继电器)，F(负) YJ(压继电器)。
斯坦福发电机介绍
斯坦福发电机简介康明斯发电机技术（中国）有限公司（原无锡新时代交流发电机有限公司）是康明斯发电机技术系统在中国的唯一的独资企业，首期投资1760万美元。
成立于1996年2月，于1997年11月正式开业。
目前年生产能力为65,000台发电机。
康明斯发电机技术系统有50多年成功地满足顾客需要的经验，是世界交流发电机技术的先导，康明斯发电机技术系统拥有全球销售和服务网络，并在英国、美国、中国、印度有生产工厂。
无锡工厂完全按照康明斯发电机技术系统的设计及工艺标准来制造斯坦福交流发电机。
产品设计、材料、生产、试验均由英方人员直接管理控制。
体积小，重量轻，技术先进，性能可靠是斯坦福发电机的重要特性。
康明斯发电机技术系统制造的斯坦福发电机可与世界上所有柴油机配套，如康明斯、帕金斯、VOLVO、MTU、道依茨、卡特彼勒和国产95、130、135、150、190系列等柴油机。
各系列产品成功供应发电机组成套厂家，广泛应用于铁路、船舶、邮电通信、军工、油田、交通、高层建筑及冷藏集装箱等领域。
康明斯发电机技术系统所生产的发电机系列为:BC16、BC18、UC224、UC274、HC4、HC5、LV6、HC7。
功率范围为:6.5KW －2000KW。
HC系列的发电机为无刷旋转磁场结构，电压最高达660V/50HZ或60HZ，满足BS5000标准第三部分和其他国际标准。
在HC4,HC5,HC6/LV6,HC7四个机座号中，200KW-2000 KW范围内，可选1500rpm(50HZ)或1800rpm（60HZ）、4极的发电机。
在HC6/LV6和HC7两个机座号中，224KW-1300KW范围内，可选1000rpm（50HZ）或1200rpm(60HZ)、6极的发电机。
机座号位HC4和HC5的发电机，其励磁系统可为使用AS440或SX421AVR的定子供电或为使用MX341或MX321AVR的永磁发电机（PMG）励磁，机座号位HC6/LV6和HC7的发电机使用MX341或MX321AVR的永磁发电机（PMG）励磁系统。
马拉松MX系列发电机英文说明书
MAGNAMAXGENERATOR INSTALLATION OPERATION, AND MAINTENANCEMANUALTABLE OF CONTENTSTABLE OF CONTENTS (2)SAFETY (6)GENERAL INFORMATION (7)MECHANICAL DESIGN (7)General (7)Conduit Box (7)MagnaMAX Unirotor TM Construction (7)Adapters and Drive Discs (7)ELECTRICAL DESIGN (8)Temperature Rise (8)Standby Generator Ratings (8)Premium Insulation System (8)Power Factor (8)MagnaMAX Voltage Regulator (8)HOW TO READ A MODEL NUMBER (9)INSTALLATION (10)RECEIVING YOUR MAGNAMAX GENERATOR (10)UNPACKING AND HANDLING (10)STORAGE (10)PREPARATION FOR USE (10)GENERATOR MOUNTING - SINGLE BEARING (10)GENERATOR MOUNTING-TWO BEARING (11)BELT DRIVE (11)ENVIRONMENTAL CONCERNS (11)ELECTRICAL CONNECTIONS (12)GENERATOR LEAD CONNECTIONS (12)12 LEAD HIGH WYE CONNECTION (13)12 LEAD LOW WYE CONNECTION (13)12 LEAD HIGH DELTA CONNECTION (14)12 LEAD LOW DELTA CONNECTION (14)10 LEAD HIGH WYE CONNECTION (15)10 LEAD LOW WYE CONNECTION (15)6 LEAD WYE CONNECTION (16)6 LEAD DELTA CONNECTION (16)3 LEAD DELTA CONNECTION (17)4 LEAD WYE CONNECTION (17)DOUBLE DELTA -- SINGLE PHASE CONNECTION (18)LOW ZIG ZAG -- SINGLE PHASE CONNECTION (18)HIGH ZIG ZAG -- SINGLE PHASE CONNECTION (18)PARALLELING OPERATIONS (19)PRIME MOVER (19)VOLTAGE REGULATOR (19)SWITCHGEAR (19)PARALLELING BASICS (19)REACTIVE LOAD CONTROL (20)PARALLELING CIRCUITRY (20)THYRISTOR OR SCR LOADING (21)OPERATION (21)PRE-START INSPECTION (21)STARTING-UP THE GENERATOR (22)FIELD FLASHING (22)VOLTAGE ADJUSTMENTS (22)OTHER ADJUSTMENTS (23)MAINTENANCE (23)GENERAL INFORMATION (23)AIR INTAKE AND EXHAUST (23)ELECTRICAL CONNECTIONS, WINDINGS (24)LUBRICATION (24)DRYING ELECTRICAL INSULATION (26)Space Heaters (26)Oven (26)Forced Air (26)“Short Circuit” Method (26)CLEANING METHODS (27)Solvents (27)Cloth and Compressed Air (27)Brushing and Vacuum Cleaning (27)Shell Blasting (27)Steam Cleaning (27)DISASSEMBLY (28)REMOVAL FROM PRIME MOVER (28)CONDUIT BOX REMOVAL (29)EXCITER STATOR (FIELD) REMOVAL (30)EXCITER ARMATURE (ROTOR) REMOVAL (30)PMG STATOR REMOVAL (31)MAIN ROTOR REMOVAL (33)FRONT END BRACKET REMOVAL (35)EXCITER INSPECTION (35)EXCITER STATOR (35)EXCITER (ROTOR) ARMATURE (36)PMG INSPECTION (37)PMG STATOR (37)PMG ROTOR (37)MAIN ROTOR INSPECTION (37)BEARING (37)FAN (38)MAIN ROTOR CORE AND WINDINGS (40)DRIVE DISCS (SINGLE BEARING GENERATORS ONLY) (40)FRONT (EXCITER) END BRACKET INSPECTION (40)DRIVE END BRACKET OR SAE ADAPTER INSPECTION (41)MAIN STATOR INSPECTION (42)FRONT END BRACKET INSTALLATION (42)MAIN ROTOR INSTALLATION (42)PMG INSTALLATION (45)EXCITER INSTALLATION (46)CONDUIT BOX INSTALLATION (47)ASSEMBLY TO PRIME MOVER (48)TROUBLESHOOTING (50)INTRODUCTION (50)SYMPTOM: (51)NO VOLTAGE OR RESIDUAL VOLTAGE (51)LOW VOLTAGE - (52)NO LOAD (52)LOW VOLTAGE WHEN LOAD IS APPLIED (53)HIGH VOLTAGE (53)VOLTAGE IS FLUCTUATING (54)OPERATES SATISFACTORILY WHEN COLD, BUT SHUTS DOWN WHEN WARM (54)BUILDS VOLTAGE FROM STARTUP,THEN GOES TO LOW (RESIDUAL) VOLTAGE (54)EQUIPMENT RUNS NORMALLY ON UTILITY POWER, BUT WILL NOT RUN ON GENERATOR SET (54)GENERATOR TESTING (55)VISUAL INSPECTION (55)CONSTANT EXCITATION (12V BATTERY) TEST (55)MEASURING VOLTAGES (56)TYPICAL VOLTAGE MEASUREMENTS (57)Generator Output Voltage (57)Regulator Output (Exciter Stator Input) (57)Regulator Sensing (57)Regulator Input Volts (PMG Output Volts) (57)CURRENT (AMP) MEASUREMENTS (57)MEASURING RESISTANCE (58)Main Stator (58)Exciter Rotor (58)TESTING DIODES (RECTIFIERS) (58)INSULATION RESISTANCE - MAIN STATOR (59)GENERATOR TESTING (59)INSULATION RESISTANCE - MAIN ROTOR (59)INSULATION RESISTANCE - EXCITER STATOR (60)INSULATION RESISTANCE - EXCITER ROTOR (60)MAIN ROTOR FIELD AC IMPEDANCE TEST (60)MAGNAMAX EXPLODED VIEW (61)STANDARD TOOLS (64)SPECIAL TOOLS (65)MISCELLANEOUS (66)PREPARATION FOR SHIPMENT OR EXTENDED STORAGE (66)SHIPPING INSTRUCTIONS (66)STORAGE INSTRUCTIONS (66)TABLE 12-1: MAGNA MAX - FASTENER AND TORQUE SPECIFICATIONS (68)TABLE 12-2: CAPSCREW TORQUE VALUES (69)TABLE 12-3:EXCITATION DATA -60 HZ - 1800 RPM (70)TABLE 12-3:EXCITATION DATA -50 HZ - 1500 RPM (71)TABLE 12-5: RESISTANCE VALUES - MAIN WINDINGS (72)TABLE 12-6: RESISTANCE VALUES - EXCITER WINDINGS (73)SAFETYPLEASE REMEMBER SAFETY FIRST. If you are not sure of the instructions or procedures, seek qualified help before continuing.This service manual emphasizes the safety precautions necessary during the installation, opera-tion, and maintenance of your generator.Each section has caution and warning messages. These messages are for your safety and the safety of the equipment involved. If any of the cautions or warnings is not readily understood, seek clarification from qualified personnel before proceeding.Before any service work is done, disconnect all power sources and, where appropriate, lock out all controls, to prevent an unexpected start-up of the generator set. Proper grounding in compliance with local and national electrical codes must be provided. These safety precautions are necessary to prevent potential serious personal injury, or even death.The hazards associated with lifting or moving the generator are pointed out in the installation and service sections; incorrect lifting or moving can result in personal injury or property damage.Whenever the generator is running, always assume and proceed as if voltage is present. Residual voltage is present at the generator leads and at the regulator panel connections, even with the regulator fuse removed. Caution must be observed, or serious personal injury or death can result.Whenever solvents, cleaners, or flammable liquids are present, adequate ventilation must be available to avoid fire, explosion, and health hazards. Always avoid breathing vapors and use suitable personal protective equipment to prevent personal injuries. (Such as eyes, face, and hand protection.)This manual is not intended to be a substitute for properly trained personnel. Only qualified trained people should attempt repairs. The cautions and warnings point out known conditions that are potentially dangerous. Each installation will create its own set of circumstances. No manual can cover every possible situation.When in doubt, ask. Don’t be embarrassed to ask, “dumb questions”. Remember that dumb questions are much easier to handle than dumb mistakes.GENERAL INFORMATION MECHANICAL DESIGNGeneralAll single and two bearing units are manufactured with cast iron end brackets and adapters, and fabricated steel frames. Flexible drive discs and SAE adapters are machined to SAE standards. Pre-lubricated, regreasable, shielded ball bearings are used on MagnaMAX generators. Standard units are fully guarded. Drip proof shields are available as an option.Conduit BoxThe large end mounted conduit box is con-structed of formed sheet steel that will allow the addition of top mounted control packages. Refer to Marathon Electric for top mounted controls of more than 240 lbs. There is ample room inside the conduit box for a circuit breaker (through 800A Frame) and other options. The conduit box cover properly directs outside ventilating air through the generator.MagnaMAX Unirotor TM Construction An aluminum die cast rotor core affords high mechanical integrity and low vibration at operating speeds. Amortisseur winding and coil supports are die cast as an integral part of the rotor. Laminations are 4-pole, one piece laminations which are shrunk fit and keyed to the shaft. No dovetails, cross bolts or other pole to shaft connecting devices are used. The cast unidirectional aluminum alloy ventilation fan provides even air distribution to maximize cooling and generator efficiency.Adapters and Drive DiscsAll single bearing units are available with several adapters and drive disc arrangements. These can be shipped to order or can be changed in the field with standard shop tools. When changing flexible drive discs, spacers are used between the discs and the cast iron hub to maintain SAE standard dimensions.ELECTRICAL DESIGNAll standard products have 2/3 pitch main windings to eliminate the third harmonic. This serves to lower operating temperatures, give lower harmonic content and better waveform, and extend the overall life of the generator.Temperature RiseAll ratings and frame sizes are based on NEMA and CSA Class F and Class H temperature rises on both the rotor and stator windings. Ratings for British, German, French, IEC and all popular marine agencies are available.Standby Generator Ratings Synchronous generators used on emergency backup power can have temperature rises up to 25°C above those for continuous operation. (NEMA MG1 -22.40 and MG 1-22.84).Premium Insulation SystemAll MagnaMAX generators are built with Class H or better insulation materials. All standard generators are suitable for continuous duty at Class F temperature rise and will give equivalent or better winding life expectancy to generators supplied with Class A or B insulation systems operated within their temperature limits. The varnishes and epoxies used are synthetic, non-hygroscopic. Multiple dip and bake cycles of the main winding, plus a final coat of epoxy, make the standard winding moisture and fungus resistant. The MagnaMAX rotor is wet wound with thermo-setting epoxy applied between each layer, plus a final coating of epoxy for moisture and abrasion resistance. MagnaMAX generators can be ordered with an epoxy vacuum pressure impregnated insulation system as an option. (MagnaMAX generators with form wound coils include VPI as standard.)Power FactorAll standard generators are designed for operation at rated kVA at 0.8 lagging power factor but can be operated at rated kVA over the 0.8 to 1 .0 power factor range. MagnaMAX Voltage RegulatorThe standard voltage regulator is a fully encapsulated, static types with a solid state build up circuit. Standard features include 3-phase RMS sensing, paralleling, adjustable under frequency protection, and over excitation protection. The regulator meets EMI suppression to Mil Std-461B, part 9. An optional feature is adjustable armature current limiting. See the regulator manual for more information.HOW TO READ A MODEL NUMBERIt is extremely important to properly identify the machine when requesting parts or service. Always have the generator model number and serial number when requesting information from the factory. We cannot help you without this information.An Example For MagnaMAX Generators 431RSL 2000 AA - 000Character Category Description1st three characters Frame Number4th character Winding type R—Random WoundF—Form Wound5th character Bearing arrangement S—1 BearingD—2Bearings6th character Voltage range L—Up to 480 voltsM—1000-6600 voltsS—600 volts7th Character Product style4-Magna8th Character Type9th & 10th Character Wk2 Code11th Character Modification A-Z assigned sequentially 12th Character Mounting Arrangement A-Y see chart figurer 2-1 13th, 14th & 15th characters Modification numbers For internal use only Arrangement Adapter SAE Size Drive Disc SAE SizeA311-1/2B211-1/2C48D310E111-1/2F114G47-1/2H1DelcoJ1/214K210L1/2DelcoM014N2Small Delco0None NoneP018S0DelcoU0018V46-1/2W0021Y410Figure 2-1INSTALLATIONRECEIVING YOUR MAGNAMAX GENERATORUpon receipt of the generator, it is recommended that it be carefully examined for possible damage incurred in shipment. The generator was given to the Freight Company in good condition, and they are responsible for the product from our dock to yours. Any damage should be noted on the freight bill before accepting the shipment. Claims for damages must be promptly filed with the Freight Company. UNPACKING AND HANDLINGRead all instruction cards carefully. When lifting, attach an overhead crane to the lifting lugs on the generator frame. Apply lifting forces in a vertical direction.WARNINGTHE LIFTING LUGS ON THE GENERATOR ARE DESIGNED TO SUPPORT THE GENERATOR ONLY.DO NOT LIFT COMPLETE GENERATOR SET BY MEANS OF LIFTING DEVICES ON THE GENERATOR. PERSONAL INJURYOR QUIPMENT DAMAGE MAYOCCUR.STORAGEIn the event that the generator is not to be installed on the prime mover immediately, it is recommended that it be stored in a clean, dry area that is not subject to rapid changes in temperature and humidity. See "STORAGE INSTRUCTIONS" for more information.PREPARATION FOR USEAlthough the generator is carefully inspected and tested in operation before it leaves the factory, it is recommended the unit be thoroughly inspected. The insulation on the wire should be inspected and all bolts should be checked for tightness.Remove all shipping tapes, bags, blocks, and skids, which are used to prevent vibration and rotor movement during shipment. Dry, low-pressure compressed air of approximately 30 PSI (206 KPA) can be used to blow out the interior of the generator. In the case of two bearing machines, it is possible to turn the rotor by hand to make sure that it rotates smoothly without binding.If the machine has been in storage for a year or longer it is recommended that it be lubricated according to the lubrication instructions and chart supplied in the maintenance section.If the machine has been exposed to damp, humid conditions the insulation resistance should be checked. Refer to the instructions supplied in this manual.GENERATOR MOUNTING - SINGLE BEARINGSingle bearing generators are provided with an SAE flywheel adapter and flexible drive discs. Very close tolerances are maintained in the manufacture of the generator so that the alignment procedure is extremely simple. A coupling hub of nodular iron is shrunk on the shaft and special steel drivediscs are bolted to the hub. Holes are provided in the periphery of the coupling disc, which correspond to tapped holes inthe flywheel. The outside diameter of the discs fits in a rabbet in the flywheel so that concentricity is assured in all cases.WARNINGDO NOT APPLY ANY FORCE TO THE GENERATOR FAN FOR LIFITNG OR FOR ROTATING THE GENERATORROTOR. DISREGARDING THESEINSTRUCTIONS MAY CAUSE PERSONAL INJURY OR EQUIPMENTDAMAGECAUTION:GRADE 8 CAPSCREWSOR GRADE 8 PLACE-BOLTS AND HARDENED WASHERS ARE REC-OMMENDED TO MOUNT THE DRIVE DISCS TO THE FLYWHEEL.DO NOT USE HELICAL OR OTHER LOCKING DEVICES UNLESS APPROVED.The SAE adapter and the flywheel housing are designed to match each other with no further alignment necessary. Shims may be necessary under the feet of the generator to insure a solid mounting. See THE SERVICE SECTION for more information. GENERATOR MOUNTING-TWOBEARINGTwo bearing generators are provided with a shaft extension and key way. For direct-coupled sets the assembler furnishes a flexible coupling which is installed between the driver and the generator shaft.IMPORTANT: Aligning the two machinesas accurately as possible will reduce vibration, increase-bearing life, and insures minimum coupling wear. It may be necessary to shim the generator feet for proper support and alignment. Consult the coupling manufacturer’s instructions for alignment specifications and procedures. BELT DRIVEPlease refer to Marathon Electric for applications involving belt driven installations.ENVIRONMENTAL CONCERNSDirt, moisture, heat, and vibration are enemies of electrical equipment. The ambient temperature should not exceed the value shown on the generator nameplate. Generators for outdoor application should be protected from the elements by housings with proper openings for ventilation. This protection should be designed to prevent the direct contact of wind driven rain, snow, or dust with the generator. In moist or humid areas, such as the Tropics and marine serv-ice, additional protection is recommended. Although the standard windings are humidity and moisture resistant, special insulation and accessories such as space heaters can increase generator life. In extremely dirty and dusty environments a means of providing filtered cooling air to the generator is recommended. Please refer to Marathon Electric for filter kits that are available.ELECTRICAL CONNECTIONSThe generator conduit box construction allows conduit to enter the top, bottom, or either side of the box. A hole-saw or any suitable tool can be used to provide for the conduit entrance. Protect the interior of the generator from shavings when drilling or sawing. An approved connector must be used in conjunction with the conduit.To minimize the transmission of vibration, it is essential that flexible conduit be used for all electrical cable entrance to the generator. Refer to the connection diagram supplied with the generator and / or the proper diagrams shown in this section. Install all intercomponent and external wiring in accordance with the regulations of the national and local electrical codes. Clean all contact surfaces to assure good electrical bonding with the generator lugs or bus bars. Use heavy-duty terminal lugs or good quality clamps for making all connections. Insulate all connections in accordance with national and local regulations.Be sure the generator frame is grounded to all the other components of the system with a ground wire in accordance with national and local regulations.GENERATOR LEAD CONNECTIONS The electrical connections in the conduit box should be made in accordance with the appropriate “connection diagram.” Use the diagram appropriate for the number of leads and voltage range required. Refer to the drawings supplied with the generator and to drawings in this section.The final voltage setting is established within the selected range by an adjustment of the voltage regulator.CAUTION:SOME GENERATORS HAVE MULTIPLE, IDENTICALLY MARKED, CABLES FOR EACH LEAD. CONNECT ALL IDENTICALLY MARKED CABLES TOGETHER WHEN MAKING CONNECTIONS.PARALLELING OPERATIONSMagnaMAX generators come standard with amortisseur windings die cast as an integral part of the rotor. This exclusive, Unirotor TM, construction makes all MagnaMAX generators suitable for paralleling operations when the proper control equipment is added. Paralleling with other generator sets and / or with the utility power grid offers a number of advantages. Multiple unit installations increase power capacity; they can be added or removed from the line depending on the load requirements; they can be better maintained and repaired (since single source breakdown would mean total loss of power), and they often provide more reliable, efficient, and economical operation.Successful parallel operation means that the generators deliver power to the external system without delivering power to each other, or accepting power from the load bus or power grid. Additional equipment is necessary to insure safe and successful operation. PRIME MOVERThe prime mover provides the speed and torque which will be necessary to keep the machines in synchronized operation. A governor controls the prime mover's speed. The governor will directly control the watt or kW output and frequency of the unit. The governor must have special paralleling provisions to permit parallel operation with the other machines.VOLTAGE REGULATORThe voltage regulator controls the generator output voltage and the reactive power supplied by the generator. When two or more ac generators operate in parallel, the voltage regulator must have paralleling provisions (either internally or external to the regulator) to control the reactive or VAR load while it is in parallel operation. A separate paralleling current transformer is required to sense the reactive current and signal the voltage regulator. This additional paralleling circuitry is absolutely necessary to control the reactive current flowing between the generator sets. SWITCHGEARThere are additional relays and breaker controls that are necessary to insure safe, trouble free operation of paralleled units. Reverse power relays monitor the direction of power flow to insure that the generator is delivering power, not accepting it. These power relays control breakers, which are a means of connecting and disconnecting the gen-erator from the load. The total system can include over-voltage, over-current protection, under fre-quency protection, power factor correction provi-sion and a variety of associated control equipment from manual switchgear to microprocessors. The amount of control gear and level of sophistication will be determined by the needs and requirements of the particular application.PARALLELING BASICSThe following points are basic criteria which must be met before two units can be paralleled. THIS IS NOT MEANT TO BE SPECIFIC INSTRUCTIONS FOR PARALLELING OPERATION.1. Additional paralleling circuitryA. Voltage regulator-paralleling provisionsB.Paralleling current transformer(s)C. Paralleling provisions on governor controlsD. Switchgear2. The voltage and frequency must be the same for all sets with voltages in phase.3. The voltage regulation characteristics of the individual generators should be similar.4. The generators must have the same phase rotation.5.The driving engines should have the same speed regulation characteristics and the governors should be adjusted to give the same speed regulation.Before operating generator sets in parallel, each set should be checked by starting, operating, and adjusting the sets as individual units before attempting paralleling. REACTIVE LOAD CONTROLWhen two identical generators are operating together in parallel and an unbalance occurs in field excitation, circulating currents begin to flow between the generators. This current will appear as a lagging power factor or inductive load to the highly excited generator, and as a leading power factor or capacitive load to the generator with the lower field current. This is known as the reactive circulating current and there are two methods of controlling it in parallel operation:1. Reactive droop compensation. (Formerly known as parallel droop compensation.)The bus voltage droops, or decreases, as the reactive lagging power factor load is increased.2. Reactive differential compensation. (Formerly known as cross current compensation.) The reactive differential compensation circuit allows parallel generators to share reactive loads with no decrease or droop in generator voltage.The circuit must meet the following criteria:A.All paralleling current transformers for all the generators being paralleled must be included in the secondary interconnection loop.B. When different size generators are paralleled all paralleling current transformers must have the same proportional ratios that give approximately the same secondary current.C. Voltage regulator paralleling circuitry must be the same.D. Current transformer secondary and the generator lines must be isolated electrically.E. It is also desirable to have an auxiliary contact on the main generator breaker to short the parallel CT secondary when that breaker is open (not connected to the load bus).Because of the above criteria, reactive differential compensation cannot be used when paralleling with the utility power grid. There is no limit, however, in the number of generators that can be included in this type of circuit. PARALLELING CIRCUITRYBecause of the number of variables involved in paralleling generator sets, every installation will have its own circuitry and methods or procedure of bringing paralleled units on line. There are numerous ways of connecting paralleled units and an almost unlimited variety of applications and associated equipment.When parallel operation is desired, it is important that the control manufacturer, the generator manu-facturer, and the systems engineer work together to insure the proper selection of all components. Please refer to Marathon Electric for application assistance.THYRISTOR OR SCR LOADING Solid state electronic control devices which utilize thyristors or SCR firing circuits (such as variable frequency induction motor controls, precision motor speed controls, no-break powered battery chargers, etc.) can introduce high frequency harmonics which adversely affect or destroy the normal waveform of the generator. This creates additional heat in the generator stator and rotor, and can cause overheating. These devices can and do present problems to non-utility power generating equipment or any limited power bus system. The problems that can occur are not limited to the generator itself, but can effect the solid state control device, the equipment it controls, other associated loads, monitoring devices or a number of combinations over the entire system.MagnaMAX generators can supply power to thyristor or SCR loads when properly applied. The standard voltage regulator is PMG powered and senses 3 phase RMS voltages for maximum stability against severely distorted waveforms. SCR type applications such as cranes, shovels, etc., require special consideration of the generator insulation system due to greater dielectric stress and severe environmental conditions. It is impor-tant that the control manufacturer, the generator manufacturer, and the systems engineer work together to insure the proper selection of all components. Please refer to Marathon Electric for application assistance. OPERATIONPRE-START INSPECTIONBefore operating the generator for the first time, the following checks are recommended.1. A visual inspection should be made to check for any loose parts, connections, or foreign materials2. Check for clearance in the generator and exciter air gap. Be sure the generator set turns over freely. Bar the generator over by hand at least 2 revolutions to be sure there is no interference.WARNINGDO NOT APPLY ANY FORCE TO THEGENERATOR FAN FOR LIFITNG ORFOR ROTATING THE GENERATORROTOR. DISREGARDING THESEINSTRUCTIONS MAY CAUSE PERSONAL INJURY OR EQUIPMENTDAMAGE3. Check all wiring against the proper connection diagrams and make sure all connections are properly insulated. Support and tie leads to keep them from being damaged by rotating parts or by chafing on sharp corners.4. Be sure the equipment is properly grounded.5. Inspect for any remaining packing materials and remove any loose debris, building materials, rags, etc. that could be drawn into the generator.6. Check fasteners for tightness.7. Check to be sure no tools or other hardware have been left inside or near the machine.8. Install and check to be sure all covers and guards are in place and secure.WARNINGRESIDUAL VOLTAGE IS PRESENT AT THE GENERATOR LEADS AND AT THE REULATOR PANEL CONNECTIONS EVEN WITH THE REGULATOR FUSE REMOVED.CAUTION MUST BE OBSERVED OR SERIOUS PERSONAL INJURY OR DEATHCAN RESULT.STARTING-UP THE GENERATORThe following procedure should be followed for starting-up the generator for the first time:1.The generator output must be disconnected from the load. Be certain that the main circuit breaker is open.2.D isable the voltage regulator by removing the fuse.WARNINGDO NOT OVERSPEED THEGENERATOR. EXCESSIVE CENTRIFUGAL FORCES COULD DAMAGE THE ROTATING FIELDS. BE PREPARED FOR AN EMERGENCYSHUTDOWN.3.F ollow the manufacturer's instructions and start the prime mover. Check the speed and adjust to the RPM shown on the generator nameplate.4.Replace the regulator fuse and adjust the voltage to the required. Check all line to line and line to neutral voltages to be sure they are correct and balanced. If the voltages are not correct shut down immediately and recheck all connections.5. Close the main circuit breaker and apply the load.6. Monitor the generator output current to verify it is at or below nameplate amps.7. Adjust engine speed at full load to 1800 rpm for 60 hertz, 1500 rpm for 50 hertz. (Refer to prime mover/governor instruction manuals.)8. Before stopping the engine, remove the load by tripping the main circuit breaker.FIELD FLASHINGThe standard MagnaMAX generator is supplied with a PMG (permanent magnet generator). It will never require field flashing. In rare cases where a special generator may be furnished without a PMG, refer to the factory for more detailed information. Include the complete generator model and serial number.VOLTAGE ADJUSTMENTSThe voltage regulator controls the generator output voltage. There is a cover to access the controlpanel on the side of the generator conduit boxFigure 4-1Figure 4-2 Regulator Access Refer to the regulator manual for detailed information. In cases where special or remote mounted regulators are used, refer to instructions supplied by the generator set assembler and to the voltage regulator manual.。
田径比赛项目常用英语单词汇编
田径比赛项目常用英语单词汇编田径比赛项目常用英语单词：Athletics 田径race 跑middle-distance race 中长跑long-distance runner 长跑运动员sprint 短跑 (美作:dash)the 400 metre hurdles 400米栏marathon 马拉松decathlon 十项全能cross-country race 越野跑jump 跳跃jumping 跳跃运动high jump 跳高long jump 跳远 (美语:broad jump)triple jump, hop step and jump 三级跳pole vault 撑竿跳throw 投掷throwing 投掷运动putting the shot, shot put 推铅球throwing the discus 掷铁饼throwing the hammer 掷链锤throwing the javelin 掷标枪walk 竞走初中英语单词分类大全-体育运动-体育项目gymnastics 体操gymnastic apparatus 体操器械horizontal bar 单杠parallel bars 双杠rings 吊环trapeze 秋千wall bars 肋木side horse, pommelled horse 鞍马weight-lifting 举重weights 重量级boxing 拳击Greece-Roman wrestling 古典式摔跤hold, lock 揪钮judo 柔道fencing 击剑winter sports 冬季运动skiing 滑雪ski 滑雪板downhill race 速降滑雪赛,滑降slalom 障碍滑雪ski jumping competition 跳高滑雪比赛ski jump 跳高滑雪ice skating 滑冰figure skating 花样滑冰roller skating 滑旱冰bobsleigh, bobsled 雪橇。
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斯坦福马拉松西门子英格利莱森玛法拉弟科私威克三波ABB 德丰朗特发电机电球维修保养同步发电机，俗称“电球”柴油发电机组一般是采用同步发电机(也俗称电球) 将柴油发动机的旋转机械能转为电能。
各种用电设备要依靠它发出的电力工作,因此对同步发电机的工作性能要求是很高的。
同步发电机的维修工作原理同步发电机是根据电磁感应原理制造的。
主要组成部分如图1。
现代交流发电机通常由两部分线圈构成;为了提高磁场的强度,一部分线圈绕在一个导磁性能良好的金属片叠成的圆筒内壁的凹槽内,这个圆筒固定在机座上称为定子。
定子内的线圈可输出感应电动势和感应电流,所以又称其为电枢。
发电机的另一部分线圈则绕在定子圆筒内的一导磁率强的金属片叠成的圆柱体的凹槽内,称为转子。
一根轴穿过转子中心并将其紧固在一起,轴两端与机座构成轴承支撑。
转子与定子内壁之间保持小而均匀的间隙且可灵活转动。
这叫做旋转磁场式结构的无刷同步发电机。
工作时,转子线圈通以直流电形成直流恒定磁场,在柴油机的带动下转子快速旋转,恒定磁场也随之旋转,定子的线圈被磁场磁力线切割产生感应电动势,发电机就发出电来。
图1 双轴承发电机剖视图转子及其恒定磁场被柴油机带动快速旋转时,在转子与定子之间小而均匀的间隙中形成一个旋转的磁场,称为转子磁场或主磁场。
平常工作时发电机的定子线圈即电枢都接有负载,定子线圈被磁场磁力线切割后产生的感应电动势通过负载形成感应电流,此电流流过定子线圈也会在间隙中产生一个磁场,称为定子磁场或电枢磁场。
这样在转子、定子之间小而均匀的间隙中出现了转子磁场和定子磁场,这两个磁场相互作用构成一个合成磁场。
发电机就是由合成磁场的磁力线切割定子线圈而发电的。
由于定子磁场是由转子磁场引起的,且它们之间总是保持着一先一后并且同速的同步关系,所以称这种发电机为同步发电机。
同步发电机在机械结构和电器性能上都具有许多优点。
同步发电机转子的励磁所谓励磁即是向同步发电机转子提供直流电使其产生直流电磁场的过程。
同步发电机转子凹槽内的线圈就是由称做励磁机的一个专门的设备为其供以直流电形成直流磁场的。
早期的发电机是采用单独的励磁机给转子线圈提供直流电的,系统庞大而复杂。
随着技术的进步,现代同步发电机都是将发电机与励磁机组装在一起构成一个完整的发电机。
励磁机其实就是个小发电机,它的工作原理与同步发电机一样。
所不同的是它的定子线圈和转子线圈所起的作用与同步发电机——主发电机正好相反;固定在主发电机定子旁的励磁机的定子线圈通以直流电形成直流磁场,而安装在主发电机转子轴上的励磁机的转子线圈成为输出电动势的电枢。
励磁机的转子与定子内壁之间也是保持着小而均匀的间隙。
这也称为旋转电枢式结构的无刷同步发电机。
安装在主发电机定子旁的励磁机定子线圈的直流电,是由主发电机定子线圈即电枢的部分输出电压经整流后而得到的。
与主发电机转子同轴安装的励磁机转子线圈在其定子线圈产生的磁场内旋转、切割磁力线所产生的感应电动势,经同轴安装在它旁边的整流器也就是旋转整流器变成直流电流,输到主发电机的转子线圈使其产生直流转子磁场。
从而达到了对主发电机转子线圈励磁的要求。
同步发电机输出电压的控制控制的目的就是实现在同步发电机额定负荷范围内稳住输出电压。
调控技术的理念是实时地从主发电机电枢取得电压和电流,经整流和负反馈调理后供给励磁机的定子线圈,使其产生变化规律与主发电机输出电压变化规律相反的直流电磁场,这个磁场也必然使励磁机转子电枢的输出电压及旋转整流器供给主发电机转子线圈的直流电流按同样的规律而变化。
从而起到实时调节主发电机转子磁场大小,使主发电机在额定负荷范围内保持良好输出特性的作用。
对发电机输出电压的调节过程,可以用以下的流程表示;由于负荷增加使主发电机电枢电压↓(降) →经负反馈调理后励磁机定子电流及磁场↑→励磁机转子电枢输出电压↑→旋转整流器输出电流↑→主发电机转子磁场↑→使主发电机电枢电压↑若主发电机电压升高,则其反馈调控使以上各环节作用降低,导致电压回到额定值。
可见通过励磁机实时调控主发电机转子磁场的大小,就可以稳住输出电压。
这其中起重要作用的是负反馈调节单元,通常称其为恒压励磁装置和自动电压调节器。
自动电压调节器AVR交流同步发电机常用自动电压调节器AVR这种电子部件调节励磁机定子磁场的强弱。
虽然AVR的种类很多,但性能大同小异;都是实时采样主发电机的输出电压值与预先设定的值相比较,用比较的结果去调节脉冲宽度调制器PWM;输出电压值高则调制器输出脉冲宽度窄,反之则宽。
然后再用这些脉冲去调控大功率开关器件即三极管或场效应管控制送入励磁机定子线圈的电流的时间。
从而使它的磁场强弱随着主发电机输出电压的变化而相反变化;即输出电压升高则励磁机定子磁场减小,输出电压降低励磁机定子磁场增强。
从而达到负反馈调控的目的。
图2 自动电压调节器电路原理图图2是常用的一种AVR类型。
取样自主发电机输出电压的信号从8、9两端输入到电压测量比较单元,与内部预先设定的电压值(例如380V)相比较。
比较结果以输出电压UA送入脉冲宽度调制单元PWM,输出电压UC送入低频保护单元。
电压测量比较单元的L、S、H是连接主发电机输出电压幅值调节电位器的三个端子。
脉冲宽度调制器由稳压器输出的直流电压UCC作为工作电源,以确保其性能稳定。
它的输出电压UB控制调制管VT3。
若由电压测量比较单元送来的UA大,表明主发电机输出电压升高,则大的UA就会使脉冲宽度调制器输出的脉冲UB的宽度变窄。
窄的脉冲就会使VT3导通时间短,通过的电流少。
反之,主发电机电压降低UA变小,脉冲宽度调制器输出的脉冲UB的宽度随之变宽,从而使VT3导通时间变长,通过的电流增多。
励磁机定子线圈一端接在端子X1上,另一端接在XX1端子上。
由主发电机电枢送来的EA、EB、Ec三相电压,经过三个二极管VD10、VD11、VD12整流后,电流从X1端流入励磁机的定子线圈,由XX1流出,再经过调制管VT3和XN 端子流回主发电机电枢,形成励磁机定子线圈的励磁电流通路。
VT3是这个通路上的开关,它导通时间长,则定子线圈流过电流时间长,定子磁场强度大；VT3导通时间短,定子线圈电流少,定子磁场强度小。
AVR就是这样调控主发电机的电压的;主发电机由于负荷原因输出电压升高,电压测量比较单元输出的UA随着升高,受UA控制的脉宽调制器输出脉冲UB宽度变窄,开关管VT3导通时间短,励磁机定子磁场减弱,转子电枢电压及旋转整流器输出电流随之减小,导致供给主发电机转子的励磁电流变小,则主发电机因其转子磁场的减小而使输出电压降低。
反之,AVR的负反馈调控功能就会使主发电机的输出电压升高。
在主发电机因负荷超出额定值而输出极大电流时,柴油发动机也需随之输出巨大的动力以致导致其转速低于额定值。
低频保护单元的作用就是在这种情况下限制励磁机定子线圈里电流的超额增大。
它以电阻和电容构成的充放电支路预先设定一个低频保护点,当主发电机负荷正常时,从电压测量单元来的UC小于低频保护点,则低频保护单元输出的电压Ud高,二极管VD8被截止,Ud到不了脉宽调制器,起不了作用。
若主发电机超载则Ud变低,VD8导通,Ud和UA 就可同时作用于脉宽调制器,使其输出的脉冲UB随Ud的下降而变窄,调制管VT3导通时间随之变短,励磁电流减小励磁机定子磁场变弱,从而导致主发电机转子磁场减小。
发电机输出电压下降、电流减小。
低频保护单元起到了保护励磁机和主发电机的作用。
同步发电机的维护同步发电机是柴油发电机组的关键部分。
为柴油发电机组建立一个合适的工作环境,做好日常维护是十分必要的。
发电机房内的高温、潮湿和空气污染物是引起发电机故障的最常见因素。
粉尘、灰尘和其它空气污染物的积累会引起绝缘层的性能变坏,不仅易形成对地的导电通路,还会使转子轴承部分的摩擦力增大而发热。
湿气以及空气污染物中的湿气极易在发电机内形成对地的漏电通路,引起发电机故障。
机房内温度过高会使发电机组工作时产生的热量难以散出,造成其输出功率下降、机组过热。
所以机房的防尘、防潮湿、通风降温就必须引起足够的重视。
无论是单轴承发电机还是双轴承发电机,它们的转子轴与柴油发动机主轴之间连接的同轴度要求很高。
长时期运行后的机组有时同轴度可能降低,导致发电机燥声增大,温度过高。
应定期检查、维护以保持同轴度良好。
负荷超出发电机的额定负载范围,或三相负荷很不平衡,也会造成发电机效率降低和过热。
Standford marathon Siemens Inge Leigh Larsen Mar Fala brother, private Vic three wave ABB Wheelock Bronte generator electric ball repair maintenanceSynchronous generator, commonly known as "electric ball"Diesel generator set is generally adopted in synchronous generator ( also known as electric ball ) diesel engine rotating mechanical energy into electric energy. A variety of electrical equipment to rely on it sends the electrical work, so the synchronous generator performance requirements are very high.Synchronous generator repair worksSynchronous generator is based on the electromagnetic induction principle manufacturing. The main part of figure 1. Modern AC generator typically consists of two portions of the coil form; in order to improve the strength of the magnetic field, a portion of the coil wound on a magnetic properties of good metal lamination of the cylinder inner wall of the groove, the cylinder is fixed on the frame referred to stator. Stator coil can output the induced electromotive force and induced current, so also known as the armature. Generator and another part of the coil is wound on the stator cylinder of a permeability strong metal sheet laminated cylindrical groove, called rotor. A shaft extends through the center of the rotor and fasten together, both ends of the shaft and the base form bearing support. The rotor and stator inner wall between remain small and uniform gap and can rotate flexibly. This is called a rotary magnetic field type structure of brushless synchronous generator.When working, the rotor coil with DC DC magnetic field is formed, in the diesel engine driven rotor spun, constant magnetic field is rotated, the stator coil by the magnetic field lines cutting to produce induced electromotive force, the generator can generate electricity.Fig 1 the double bearing generator section viewThe rotor and the magnetic field is a diesel engine to drive a fast rotation, between the rotor and the stator are small and uniform gap in the form of a rotating magnetic field, known as the rotor magnetic field or magnetic field. The normal work when the generator stator whereby the armature is connected with a load, the stator coil is the magnetic field lines after cutting the induced electromotive force generated by the load currents induced in the formation, the current flowing through the stator coils can generate a magnetic field in the gap, known as the stator magnetic field and armature magnetic field. When the rotor, stator between small and uniform gap has emerged in the rotor magnetic field and stator magnetic field, the two magnetic field interactions constitute a composite magnetic field. The generator is composed of synthetic magnetic field of the magnetic lines cutting stator coil and power. Due to the magnetic field of the stator is composed of rotor magnetic field is induced, and they always keep one after the other and the same speed synchronization relationship, so that the generator for synchronous generator. Synchronous generator in the mechanical structure and electrical properties has many advantages.The excitation of synchronous generator rotorThe excitation of synchronous generator rotor is to provide DC power to the DC electromagnetic process. Synchronous generator rotor groove is called exciter coil by a specialized equipment for its formation for DC DC magnetic field. Early generator is used to separate the exciter rotor coil to provide DC power to the system is large and complex. With the development of technology, modern synchronous generator is the generator and exciter assembled together constitute a complete generator.The exciter is actually a small generator, its working principle and the synchronous generator. The difference is that the stator coil and the rotor coil the role of main generator and synchronous generator -- just the opposite; fixed in the main generator stator adjacent to the stator of the exciter coil with DC DC magnetic field is formed, and is mounted on the main rotor shaft of generator 's exciter rotor coil becomes the output electromotive force of the armature. Exciter rotor and stator inner wall is also maintained a small and uniform gap. This is also known as the revolving armature type structure of brushless synchronous generator. Mounted on the main generator stator side exciter stator coil DC, is composed of a main generator stator coil or armature portion of the output voltage is rectified obtained after the. With the main generator rotor coaxially mounted exciter rotor winding in the stator coil to generate a magnetic field in rotating, cutting the lines of magnetic force produced by the induction electromotive force, the coaxially mounted beside it is rotating rectifier rectifier into DC current, input to the main generator rotor coil of the DC magnetic field of the rotor. We can reach the main generator rotor coil excitation requirement.Synchronous generator output voltage controlControl is achieved in the synchronous generator rated load range to stabilize the output voltage. Regulation of technical philosophy is in real time from the main generator armature voltage and current by the rectifier to obtain, and the negative feedback adjust supply a stator of the exciter coil, make its produce variation and main generator output voltage variation instead of DC electromagnetic field, the magnetic field will also make the exciter rotor armature voltage and rotating rectifier supply main generator rotor coil DC current according to the same rule changes. In order to adjust the main generator rotor magnetic field, so that the main generators in the rated load range to maintain good output characteristic function.The generator output voltage regulating process, can use the following process representation;As the load increases the main generator armature voltage. (down ) to the negative feedback after conditioning exciter stator currents and magnetic fields up to the exciter rotor armature voltage up to rotating rectifier output current up to the main generator rotor magnetic field to make up of main generator armature voltage.If the main generator voltage increases, the feedback control to the above each link function reduces, causes the voltage to rated value.Visible through the exciter real-time regulation of main generator rotor magnetic field size, can stabilize the output voltage. Which play an important role in the negative feedback regulation unit, usually called constant-voltage excitation device and automatic voltage regulator.Automatic voltage regulator AVRSynchronous AC generator automatic voltage regulator of the AVR commonly used electronic components regulating exciter stator magnetic field intensity. Although the AVR type are many, but the performance is similar; real-time sampling of the main generator output voltage value and the predetermined value are compared, with comparable results to the regulating pulse width modulator PWM; the output voltage value is high, narrow pulse width modulator output, whereas the width. Then these pulses to control high power switching devices such as a transistor or FET controls into the exciter stator coil current time. So that the magnetic field strength as the main generator output voltage change the opposite changes; i.e. the output voltage wave exciter stator magnetic field decreases, lowering the output voltage exciter stator magnetic field enhancement. So as to achieve the purpose of negative feedback regulation.Figure 2 automatic voltage regulator circuit schematicFigure 2is a commonly used type AVR. Sampling independent generator output voltage signal from the8,9 ends and input to a voltage measuring unit of comparison, and internal predetermined voltage value ( for example380V ) phase comparison. And compare the results with the output voltage of UA into pulse width modulation unit PWM, output voltage UC into low frequency protection unit. Voltage measurement comparison unit L, S, H is connected to the main generator output voltage amplitude adjusting potentiometer three terminals.Pulse width modulator by the regulator output DC voltage of UCC as a working power supply, in order to ensure its stable performance. Its output voltage UB control modulation tube VT3. If the voltage measurement comparison unit sent UA, shows that the output voltage of the generator is increased, the UA will enable pulse width modulator output pulse width of UB. Narrow pulse will makeVT3conduction time is short, the current through the less. Conversely, the main generator voltage to reduce the UA smaller, pulse width modulator output pulse width of UB become wide, so thatVT3turn-on time is long, the current increase.Exciter stator coil end of the terminal X1, the other end of the XX1terminal. The main generator armature. EA, EB, Ec three-phase voltage, through the three diode VD10, VD11, VD12rectifier, current from the X1 end into a stator of the exciter coil, by XX1outflow, and after modulated tube VT3and XN terminals to the main generator armature, forming the exciter stator coil excitation current path. VT3 is the channel switch, conduction time is long, the stator coil current flowing through a long time, the stator magnetic field strength; VT3conduction time is short, the stator coil current, stator magnetic field intensity.This is the AVR regulation of main generator voltage due to the load causes; main generator output voltage increases, voltage measurement comparison unit output UA increasing, UA control of the pulse width modulator output UB pulse width becomes narrower, the switch tube VT3conduction time is short, the exciter stator field weakens, the rotor armature voltage and rotating rectifier output current decreases, bring about supply main generator rotor excitation current is small, then the main generator because of its rotor magnetic field decreases so that the output voltage is reduced. Conversely, negative feedback regulation of AVR function will make the main generator output voltage rise.The main generator for the load exceeds a rated value and output maximum current, diesel engine also subsequently output power that led to its rotational speed is lower than the rated value. Lowfrequency protection unit is the role of condition limiting exciter stator coil current excess increases. It composed of resistor and capacitance charge and discharge circuit set a low frequency protection, when the main generator load normal, from a voltage measuring unit of UC less than low frequency protection points, then low frequency protection unit output voltage of Ud, diode VD8is off, Ud reach the pulse width modulator, having no effect. If the main generator overload Ud becomes lower,VD8conduction, Ud and UA can simultaneously act on the pulse width modulator, the output pulse of UB with Ud decline narrowed, modulation tube VT3turn-on time become short, excitation current decreases the exciter stator magnetic field become weak, which leads to the main generator rotor magnetic field decreases. Generator output voltage, current decrease decline. Low frequency protection unit to protect the exciter and generator effect.Synchronous generator maintenanceThe synchronous generator is the key part of diesel generating set. For the diesel generator set to establish a suitable working environment, make daily maintenance is very necessary.Generator room inside the high temperature, humidity and air pollutants are the most common factors caused by fault of generator. Dust, dirt and other air pollutants accumulation will cause the bad performance of the insulating layer, not only easy to form the conductive pathways, may also make the rotor bearing part of the friction increases heating. Moisture and air pollutants in the moisture easily in the generator of the leakage path, cause the fault of generator. Room temperature is too high will make the generator generates heat when not out, causing the output power decreases, unit overheated. So the room dust prevention, damp, ventilation cooling must cause enough attention.Either a single or double bearing generator bearing generator, the rotor shaft and the diesel engine spindle is connected between the high requirement of coaxiality. Long period running of units sometimes coaxial may reduce, lead generator noise increases, high temperature. Should be checked regularly, in order to maintain concentricity good maintenance.Beyond the rated load range load generator, or a three-phase load is not balanced, also will cause the generator efficiency reduction and overheat.。