电力系统介绍_电力英语.ppt

电力英语阅读,任惠华北电力大学电力工程系（保定）,2019/12/19,HUIRENNCEPU,45-2,PowerSystemIntroduction,Powerdispatching,voltage,current,activepower,reactivepower,statusofcircuitbreakers,Statusofprotectiverelays,电力系统调度,2019/12/19,HUIRENNCEPU,45-3,2019/12/19,HUIRENNCEPU,45-4,2019/12/19,HUIRENNCEPU,45-5,2019/12/19,HUIRENNCEPU,45-6,2019/12/19,HUIRENNCEPU,45-7,2019/12/19,HUIRENNCEPU,45-8,Basics,DC/AC直流/交流Voltage电压Voltagelevel电压等级110v,220v,380v,3kV,6kV,10kV,20kV,35kV110kV,220kV,330kV,500kV,750kV,1100kVPhasevoltage相电压,linevoltage线电压Activepower（realpower）有功功率Reactivepower无功功率,2019/12/19,HUIRENNCEPU,45-9,Basics,2019/12/19,HUIRENNCEPU,45-10,2019/12/19,HUIRENNCEPU,45-11,Basics,GeneratorPowerTransformerCircuitbreakerProtectiveRelayDispatchingsystem,2019/12/19,HUIRENNCEPU,45-12,2019/12/19,HUIRENNCEPU,45-13,2019/12/19,HUIRENNCEPU,45-14,2019/12/19,HUIRENNCEPU,45-15,2019/12/19,HUIRENNCEPU,45-16,2019/12/19,HUIRENNCEPU,45-17,2019/12/19,HUIRENNCEPU,45-18,燃煤机组,2019/12/19,HUIRENNCEPU,45-19,PowerDispatching,Dispatchingregulationonpowersystem:issuedin1993byStateCouncil.Unifieddispatchingandhierarchicalmanagement:fivelevels.,国调,网调,省调,地调,县调,2019/12/19,HUIRENNCEPU,45-20,2019/12/19,HUIRENNCEPU,45-21,Powerdispatchingautomationsystem(调度自动化系统).Thetaskisprovidingtooperators(调度员)allvariouskindsofrealtimeinformationofpowersystem,makingmanagementanddispatchingdecisiontoensuresafetyandeconomicaloperationofpowersystem.SometimesitisalsocalledEMS(EnergyManagementSystem)(能量管理系统),2019/12/19,HUIRENNCEPU,45-22,EMSincludesthefollowingpoweradvancedsoftware:LoadForecasting(负荷预测),AutomatedGenerationControl(自动发电控制),StateEstimation(状态估计),TransientStabilityAnalysis(暂态稳定分析),OptimalPowerFlow(最优潮流),DispatcherTrainingSimulator(调度员培训仿真系统)ThebasicsoftheseadvancedsoftwareisSCADAsystem.,2019/12/19,HUIRENNCEPU,45-23,Thegeneratorvoltagesareintherangeof11to30kV;highergeneratorvoltagesaredifficulttoobtainbecauseofinsulationproblemsinthenarrowconfinesofthegeneratorstator.发电机机端电压范围在11kV至30kV之间。机端电压难以达到更高的原因是由于发电机定子的绝缘问题。,2019/12/19,HUIRENNCEPU,45-24,Transformersarethenusedtostepupthevoltagestotherangeof110to765kV.由升压变压器将电压升至110kV至765kV。InCaliforniathebackboneofthetransmissionsystemiscomposedmainlyof500kV,345kV,and230kVthree-phaselines.Thevoltagesrefertovoltagesfromlinetoline.加州的主干输电网由500kV、345kV和230kV的三相线路组成。上述电压指的是线电压。,2019/12/19,HUIRENNCEPU,45-25,Onereasonforusinghightransmission-linevoltagesistoimproveenergytransmissionefficiency.Basically,transmissionofagivenamountofpower(atspecifiedpowerfactor)requiresafixedproductofvoltageandlinecurrent.Lowerlinecurrentsareassociatedwithlowerresistivelosses(I2R)intheline.采用高输电线电压的原因之一是提高能量传输效率。基本上，当传输一定的功率时（在给定功率因数下），电压和线路电流的乘积一定。降低电流相当于降低线路上的电阻性损耗。,2019/12/19,HUIRENNCEPU,45-26,Theprimaryobjectiveoftheinterconnectionisimprovedservicereliability;alossofgenerationinoneareacanbemadeupbyutilizingsparecapacityinanotherarea.电网互联的主要目的是提高供电可靠性；一个区域损失的发电量可以由另外一个区域的剩余容量供给。,2019/12/19,HUIRENNCEPU,45-27,Decision:BuildorUpgradeCitySubstation城市变电站面临抉择：新建还是扩建Becausemanycitieshaveexperiencedrapidgrowth,theirsubstationshaveoftenreachedthelimitsoftheircapacity.Asaresult,downtowndistributionsystemsareoftenoverworkedandmanyneedamajorupgrade,overhaul,orexpansion.However,spaceisscarce.由于城市不断发展，许多城市变电站已经达到其负荷极限，许多配电站急需升级、检修或扩建，问题是空间不足。,2019/12/19,HUIRENNCEPU,45-28,BCHydrobuiltCathedralSquare,amajor230/12kVundergroundgas-insulatedsubstationlocated62ftunderground,in1984.BC水电公司于1984年建造了这个位于地下62ft（英尺）的230/12kV气体绝缘地下变电站。Ithasthreelevelsundergroundandanurbanparkabove.Itoriginallyhadadozen12kVfeeders,buthassinceundergoneseveralupgrades,includingtheadditionof24feedersforacurrenttotalof36.变电站建在地面以下，分为三层，地面上则是个公园，最初有12条12kV馈电线路，经过几次扩建增加了24条，目前共有36条馈电线路。,2019/12/19,HUIRENNCEPU,45-29,Usingsomedevicessuchasmagnetictemperatureindicatorsthatmeasuredifferentialtemperaturebetweenloadtap-changer(LTC)oiltanksandmaintransformeroiltanks,theutilityhasmovedfromanannualLTCbreakermaintenancescheduletoanas-neededschedule.由于使用了一些电磁温度指示器之类的装置来测量有载调压分接头油箱和主变压器邮箱之间的温差，这家电力公司不必像以前那样，每年都要进行LTC开关维修，而是根据需要随时进行维修。,2019/12/19,HUIRENNCEPU,45-30,On-linemonitoringinformationiscollectedbytheutilitysupervisorycontrolanddataacquisition(SCADA)system,andisthensenttothediagnosticsprogramwherethedataareanalyzedaccordingtopresentparameterssuppliedbyDPheretheonlyrequirementisrelativemotion,andsinceastationaryarmatureandarotatingfieldsystemhavenumerousadvantages,thisarrangementisstandardpracticeforallsynchronousmachinesratedaboveafewkilovolt-amperes.交流发电机不受任何限制，惟一的要求是相对移动，而且由于固定电枢及旋转磁场系统具有许多优点，这种安排是所有额定容量超过几千伏安的同步发电机的标准做法。,2019/12/19,HUIRENNCEPU,45-42,顺译法例句（2）,Forlargemotors,therefore,aphase-windingrotorisused,withthewindingconnectedatoneendtoeachotherandattheotherendtoslip-rings,thusenablingtheresistanceoftherotortobevariedatwill,providingagreaterstartingtorqueandsomespeedcontrol.因此，对于大型电机来说，一般采用相绕组转子，其绕线的一端互相连接，而另一端接于轴的滑环上，这样，可随意改变转子的电阻，从而可提供更大的起动转矩，并可适当控制速度。,2019/12/19,HUIRENNCEPU,45-43,倒译法,当原文结构层次与汉语相反时，要从英语原文的后面译起，自下而上，逆着原文的顺序翻译，称为倒译法。例如：Theresistanceofanylengthofaconductingwireiseasilymeasuredbyfindingthepotentialdifferenceinvoltsbetweenitsendswhenaknowncurrentisflowing.已知导线中的电流，只要求出导线两端电位差的伏特数，就不难测出任何长度的导线的电阻。,2019/12/19,HUIRENNCEPU,45-44,倒译法,Variousmachinepartscanbewashedverycleanandwillbeascleanasnewoneswhentheyaretreatedbyultrasonics,nomatterhowdirtyandirregularlyshapedtheymaybe.各种机器零件无论多么脏，形状多么不规则，当它们用超声波处理后，就可以被洗得非常干净，甚至干净得像新的零件一样。,2019/12/19,HUIRENNCEPU,45-45,分译法,为了汉语表述的方便，可将原文的长句拆开来分别译出。当长句中的主句与从句或介词短语及分词短语等多修饰的词与词之间的关系不是很密切，并且各自具有相对的独立意义时，可分解成几个部分或意思层，然后再按时间顺序、逻辑顺序有机的组合在一起，还可以增减适当的词语以便断句之间的衔接。例如，可添加或利用原文中的总括性词语作为引语，而后分述各个部分；或先将某一短语和从句分出去单独译出，在利用总括性词语把它和主句联系到一起；或先译出原文