南京工程学院期末考查报告书电气工程专业外语B院(系、部、中心)电力工程学院专业电气工程及其自动化班级电气071学生姓名褚楚学号206070819任课教师朱建忠2010年7月南京考查要求:1、对已学的课程内容进行总结,节选4篇课题作为报告的主题。2、通过文献的搜索(可借鉴Google、Yahoo和电子图书馆的外文期刊),查找数篇与课程相关的资料(一定是经过选择后的文献,要最好的)。3、通过已经掌握的专业词汇和课题背景对已查找的文献进行精心分析,分析角度可从词汇、语法和课题背景等。4、对文献进行通篇翻译,翻译最好可直译,遇拗口的语句可选择意译。5、翻译后从文中选出关键字。6、总结翻译成果,写下中心思想。7、考查报告总结(语句需简洁)。成绩Page1.TheProductionofElectricalEnergy(电能生产)1.EnglishtestFromreference1Inlargesteampowerplants,thethermalenergystoredinsteamisconvertedintoworkbymeansofturbines.Aturbineconsistsessentiallyofashaftorrotorfixedinbearingsandenclosedinacylindricalcasing.Therotorismadetoturnsmoothlybymeansofjetsofsteamfromnozzlesaroundtheperipheryoftheturbinecylinder.Thesesteamjetsstrikebladesattachedtotheshaft.Centralpowerstationsemploycondensingturbinesinwhichthesteampassesintoacondenserafterleavingtheturbine.Condensationiseffectedbythecirculationoflargequantitiesofcoldwaterthroughthetubesofthecondenser,thusincreasingtheexpansionratioofthesteamandtheconsequentefficiencyandworkoutputoftheturbine.theturbinesareconnecteddirectlytolargeelectricitygenerators.Inturbinestheactionofthesteamiskinetic.Thereisprogressiveexpansionofthesteamfromthehighpressureandrelativelysmallvolumeatwhichitenterstheturbinetothelowpressureandrelativelyverygreatvolumeatwhichitleaves.Steamismadebyheatingwaterinaboiler.Theusualboilerhasafurnaceinwhichfuelisburnedandtheheatgivenoffduringcombustionisconductedthroughthemetalwallsoftheboilertogeneratesteamatapressurewithintheboilervessel.Innuclearplants,steamisgeneratedwiththeaidofareatorinwhichthecontrolledfissionofuraniumorplutoniumsuppliesthenecessaryheatforthevaporizationofwater.Thusthereatorreplacesthesteamgeneratorofconventionalplants.Keywords:turbine,steamFromreference2Upuntilnowwehavebeenmainlyconcernedwithminimizingthecostofoperatingapowersystem.Anoverridingfactorintheoperationofapowersystemisthedesiretomaintainsystemsecurity.Systemsecurityinvolvespracticesdesignedtokeepthesystemoperatingwhencomponentsfail.Forexample,ageneratinguntilmayhavetobetakenoff-linebecauseofauxiliaryequipmentfailure.Bymaintainingproperamountsofspinningreserve,theremainingunitsonthesystemcanmakeupthedeficitwithouttoolowafrequencydroporneedtoshedanyload.Similarly,atransmissionlinemaybedamagedbyastormandtakenoutbyautomaticrelaying.Ifincommittinganddispatchinggenerationproperregardfortransmissionflowsismaintained,theremainingtransmissionlinescantaketheincreasedloadingandstillremainwithinlimit.Becausethespecifictimesatwhichinitiatingeventsthatcausecomponentstofailareunpredictablethesystemmustbeoperatedatalltimesinsuchawaythatthesystemwillnotbeleftindangerousconditionshouldanycredibleinitiatingeventoccur.Sincepowersystemequipmentisdesignedtobeoperatedwithincertainlimits,mostpiecesofequipmentareprotectedbyautomaticdevicesthatcancauseequipmenttobeswitchedoutofthesystemiftheselimitsareviolated.Ifanyeventoccursonasystemthatleavesitoperatingwithlimitsviolated,theeventmaybefollowedbyaseriesoffurtheractionsthatswitchotherequipmentoutofservice.Thisisusuallyreferredtoasasystemblackout.Keywords:powersystem,sec...