风力发电变桨系统外文翻译

中国地质学院本科毕业论文外文资料翻译系专别：业：信息工程系电气工程及其自动化姓名：9学号：02013年3月20日PAGEPAGE5外文资料翻译译文1风机变桨系统概述风力发电机组控制系统硬件分别安装在三个不同部分：机舱控制，安装在机舱内。地面控制，安装在塔架底部。变桨控制，安装在轮毂内部。人机界面触摸屏显示风机的运行状况和参数，或者启动或停止风机。风力发电机组四种控制方式：定速定浆距控制发电机直接连到恒定频率的电网,在发电时不进行空气动力学控制。定速变浆距控制发电机直接连到恒定频率的电网,在大风时浆距控制用于调节功率。变速定浆距控制变频器将发电机和电网去耦(decouples),允许转子速度通过控制发电机的反力矩改变。在大风时,减慢转子直到空气动力学失速限制功率到期望的水平。变速变浆距控制变频器将发电机和电网去耦,允许通过控制发电机的反力矩改变转子速度。在大风时,浆距控制用于调节功率。2变桨系统的工作原理定浆距风机通过叶片的失速,即改变叶片横断面周围流动的气流,导致效率的损失,从而控制风机的最大输出功率。变浆距风机是通过叶片沿其纵向轴转动,改变气流对叶片的攻角,从而改变风力发电机组获得的空气动力转矩,使发电机功率输出保持稳定。改变风力发电机组获得的空气动力转矩,使发电机功率输出保持稳定。3变桨系统和定桨系统的比较定桨距失速调节型风力发电机组定奖距是指桨叶与轮载的连接是固定的，即大/小发电机。在低风速段（与变桨距风机叶片比较机组的整体效率较低。变桨距调节型风力发电机组是指通过变桨驱动装置,带动安装在轮毂上的45°，0°，直到风力机达到额定转速并网发电；在运行过程中，当输出功率小0°位置不变，不作任何调节；当发电机输出功率达到额定功率以后，调节系统根据输出功率的变化调整桨距角的大小，使发电机的输出功率保持在额定功率。缺点是结构比较复杂，故障率相对较高。变桨系统的分类式统一变桨距控制即机组所有桨叶都由一个执行机构驱动，或者三个执行机桨距方式一般都采用液压方式。独立变桨距方式，每个桨叶都由独立的变桨距执行机构驱动，如果其中一个变桨距执行结构出现故障，其它两个桨叶仍能调节桨叶节距角,实现功率控制，而统一变桨距执行结构出现故障，只能停机维修；另外自然界的风在整个风轮扫及面上分布是不均匀的，独立桨叶控制可以根据各个桨叶上的风速不同进行调节，不仅能维持发电机输出功率，而且能减小桨叶拍打振动，因此独立桨叶控制比统一控制更具有一定的优势。独立变桨距控制将桨叶负载分别由单90°。但风力机组风速传感器安装在风轮后的机舱上，不能正确反映扫及面上的风速，因此控制时一般都以发电机额定功率或转子转速为界，即当发电机输出功率（转速）低于额定值时，进行变速恒频控制，最大捕获风能；而当输出功率（转速）高于额定值时，进行变桨距控制，维持发电机功率在额定值附近。要实现真正的独立变桨,输入变量包括桨叶节距角变化和风速，以及每情况，而且复杂的控制程序也很难在工程中实现，所以目前工程上仍然采用统一变桨，即三个桨叶同时动作。根据执行机构的类型可分为液压变桨和电动变桨。电动变桨根据所用电机可以分为直流伺服和交流伺服两种类型。直流型电变桨伺服控制系统交流型电变桨伺服控制系统结构简单﹑UPS；以便在电网突然断电或其它紧急情况停机时,变桨伺服系统可以通过自备的UPS变桨系统的组成变桨系统主要由PLC﹑可逆直流调速装置﹑直流电机﹑绝对式位置编码器PLCCAN速度和角度指令),并控制可逆直流调速装置驱动直流电机带动桨叶朝要求的方向和角度转动,同时PLC还负责蓄电池的充电控制﹑蓄电池电压的监控等辅助控制。主要技术性能指标伺服电机额定转速 2500rpm额定输出电流 17A额定转矩 20.0Nm电源电压 三相AC380V绝缘等级 F级冷却方式 自然冷却防护等级 IP64环境温度制动装置编码器伺服驱动系统

－25℃～＋40℃选件绝对值位置编码器额定输出功率 7.5KW额定输出电流 24A额定输出电压 3×0400V(AC)输入电压 3×AC380V(－25％～＋10％)过载能力 43A/30秒冷却方式 散热器外置自然冷却防护等级 IP24或更高环境温度制动电阻

－25℃～＋40℃外加配置现场总线 CAN总线保护功能

电机三相短路保护﹑过载保护﹑电源过压保护等外文原文1fanpitchSystemOverviewwindturbinecontrolsystemhardwarewereinstalledinthreedifferentpartsThecabincontrol,installedinsidethecabin.Groundcontrol,mountedonthebottomofthetower.Pitchcontrol,internallymountedonthehub.man-machineinterfaceThetouchscreendisplaystheoperationalstatusandparametersofthefan,ortostartorstopthefan.windturbinethefourcontrolwayConstantspeedgivenpitchcontrolThegenerator is directlyconnected to theconstant frequencygrid,theaerodynamiccontrolisnotperformedwhenthepowergeneration.constantspeedvariablepitchcontrolThegeneratorisdirectlyconnectedtotheconstantfrequencyofthepowergrid,powerisusedtoadjustthepitchcontrolinhighwinds.variablespeedandpitchcontrol

theTheinverterofthegeneratorandgriddecoupling(decouples),toallowtherotorspeedbytheanti-torquecontrolofthegeneratorchanges.Inhighwinds,slowdowntherotoruntilaerodynamicstalllimitpowertothedesiredlevel.variablespeedpitchcontrolInvertergeneratorandgriddecouplingchangepermittedbytheanti-torquecontrolofthegeneratorrotorspeed.Inhighwinds,thepitchcontrolisusedtoadjustthepower.2pitchsystemworksFixedpitchbyastalloftheblade,i.e.tochangetheairflowflowingaroundthebladecrosssection,resultinginalossofefficiency,therebycontrollingthemaximumoutputpoweroftheblowerfan.Thevariablepitchfanisthroughthevanestorotatealongitslongitudinalaxistochangetheangleofattackoftheairflowtotheblades,therebychangingthetheaerodynamictorqueobtainedbythewindturbinegenerator,sothatthegeneratorpoweroutputstable.Pitchservocontrolsystemastheouterringofwindpowercontrolsystem,playsaveryimportantroleinthecontrolofthewindturbine.Itcontrolsthebladepitchangleofthewindturbinecanautomaticallyadjustthesizeofthewindvelocity.Thestartofthelowwindspeed,thebladepitchcangototherightangle,sothatthewindwheelhasamaximumstartingtorque;,therebychangingwindwhenthewindvelocityistoohigh,byadjustingthebladepitch,andtochangetheangleofattackoftheairflowtothebladesaerodynamictorqueobtainedbythegeneratorset,thegeneratorpoweroutputtomaintainstability.3pitchsystemandthecomparisonoffixed-bladesystemFixed-bladeawayfromthestalladjustmenttypewindturbinegivenAwardfromtheconnectionofthepaddlewheelloadisfixed,thepitchangleisfixed,thatis,whenthewindchanges,thewindwardangleofthebladecannotbechanges,bladetheairfoilitselfhasstallcharacteristics.Whenthewindspeedishigherthantheratedwindspeed,theangleofattackoftheairflowisincreasedtoastallcondition,theeddycurrentisgeneratedonthesurfaceoftheblades,reducingefficiency,andtothepoweroutputofthegenerator.Inordertoimprovetheefficiencyofwindturbinesinlowwindspeeds,usuallyatwo-speedgenerator(ie,large/smallgenerator).Segmentrunningatlowwindspeeds,usingasmallmotortothebladesCountyhighaerodynamicefficiencyandtoimprovetheoperatingefficiencyofthegenerator.Stalladjustingtheadvantagesofthetypestallregulationissimpleandreliable,passivestallregulatedonlybythebladeswhenthewindspeedchangescausedbyvariationsinoutputpowerandthecontrolsystemwithoutanycontrol,thecontrolsystemgreatlyreduced.Thedisadvantageisthattheweightofleaves(comparisonwithvariablefanblades),paddlewheelload,towercomponentsbyalargerforce,andlowertheoverallefficiencyoftheunit.Thepitchadjustmentwindturbinesgeneratingmeansthroughthepitchdrivemeans,drivingtherotationofthebladesmountedonthehub,therebychangingthesizeofthebladepitchangle.Adjustmentmethod:Whenthewindturbineoperatingconditions,thecontrolsystemcommandspitchpitchangleadjustedto45°,andthenadjustedto0°whenthespeedreachesacertainreachtheratedspeeduntilthewindturbinetothegrid;duringoperation,whentheoutputpowerislessthantheratedpower,thepitchangletomaintainthesame,doesnotmakeanyadjustmentinthe0°position;reachratedpowerwhenthegeneratoroutputpower,theregulationsystemadjustedaccordingtothechangesintheoutputpowerofthepitchanglesize,sothattheoutputpowerofthegeneratorismaintainedattheratedpower.Thedisadvantageisthatthemorecomplexstructure,arelativelyhighfailurerate.4pitchclassificationVariablepitch unified pitch and independent pitch system accordancewithitsworkcanbedividedintotwokindsofwaysUnifiedvariablepitchcontrolthatcrewallbladesbyanexecutiveagencydrive,ordrivethreeimplementingagencies,thebladepitchanglechanges.Thetorqueofthehydraulicsystem,unifiedinalargewindturbinepitchdistanceisgenerallyhydraulically.Independentvariablepitchmode,eachbladebytheindependentpitchactuatordriver,ifonepitchimplementationofstructuralfailure,andtheothertwobladescanstilladjustthebladepitchangle,thepowercontrol,unifiedpitchimplementationofstructuralfailure,onlyamaintenanceshutdown;Further,thenatureofthewindinthesweepoftheentirewindwheelandthesurfaceisnotuniformlydistributed,independentbladecontrolmaybeadjusteddependingonthewindspeedontherespectiveblades,notonlytomaintainthegeneratoroutputpower,butalsocanreducethebladeflappingvibration,independentbladecontrolmorethanunifiedcontrolhascertainadvantages.Independentvariablepitchcontrolbladeloadbornebyasingleexecutiveagency,sogenerallyusedmotorexecution,motorinternalringgearpaddlewheelsdrivenbythedrivegear,thebladepitchanglechanges.Butthepitchprocesschangesinthepitchangleofthebladeonlyfrom0to90°.Butonwindturbineswindspeedsensorisinstalledinthecabinafterthewindwheel,cannotcorrectlyreflectthesweepandsurfacewindspeed,controlgeneratorratedpowerorrotorspeedisboundedgenerallylow,thatis,whenthegeneratoroutputpowerratedVSCFcontrol,maximumcaptureofwindenergy;higherthantheratedoutputpower(speed),pitchcontrolandmaintainthegeneratorpowerratingnear.Toachieveatrulyindependentpitchinputvariables,includingchangesinbladepitchangleandwindspeed,andeachbladeforcemultivariablecontrol,butbecauseofthewindspeedsensordoesnotreflectthewindspeedoneachblade,andthecomplexityofthecontrolprogramitisdifficulttoachieveintheproject,sotheprojectstillunifiedthatthethreebladesatthesametime.canbedividedaccordingtothetypeoftheimplementingagencyhydraulicpitch,andtheelectricpitch.electricpitchdependingonthemotorcanbedividedintotwotypesDCservoandACservo.dcelectricpitchservocontrolsystemDCpitchsystemmainlyconsistsofthefollowingcharacteristics:aserieswoundDCmotorstartingtorque.Tensofmetersindiameterbladerotationweighingseveraltons,isgood;DCsteplessspeed,low-speedperformance;doesnotallowno-loadoperation,otherwiseitwouldcause"Speed";motorcarbonbrush,maintenancedifficulties;CanadianThebackupbatteryismoreconvenient.ACelectricpitchservocontrolsystemAC-typepitchsystemmainlyconsistsofthefollowingcharacteristics:ACpermanentmagnetsynchronousmotors,orACinductionmotor,simplestructure,maintenanceworkloadissmall;representsthedevelopmentdirectionoftheservocontrolsystem;mustbeaddedtotheUPS;suddenpowerfailuresothatthegridorotheremergencyshutdown,thepitchservosystemcanbrieflyownedtheUPSpowersupplysystemtocompletetheclosingpaddleandtakeothersafetymeasurespredeterminedpitch.5ThecompositionofthepitchsystemThepitchsystemmainlybythePLC,reversible,absolutepositionencoderDCspeeder,DCmotorbythebatteryasabackuppowersupply.PLCcomposedofthepitchcontrolsystemviafieldbus(egCANbus)andthemaincontrolsystemco