無功補償外文翻譯

西南交通大學

本科畢業(yè)設(shè)計英文文獻翻譯年級:2010級學號:專業(yè):電氣工程及其自動化2014年6月IndustrialenterprisesofreactivepowercompensationFrom:PowerSystemAnalysisandDesignAbstractTheimprovementofindustrialenterprisesistoimprovethepowerfactorofelectricpowerefficiency，animportantmeansofsavingenergy.Inthispaper，theoreticalanalysisandapplicationexamplesoftheindustrialenterprises，thesignificanceofreactivepowercompensationandtheroleandviewofthecurrentpowersystem，industrialenterprises，theproblemsfortheproposedimprovementsandmeasures.IntroductionInindustrialenterprises，thevastmajorityofelectricalequipmentbelongstoperceptualload，thesedevicesinoperationtoabsorbalargenumberofreactivepower.Anincreaseinreactivepowersupplysystempowerfactortolowersystemvoltagedroptooccur，electricalequipmentnotfullyutilized，increasinglinelossesandlower-poweredequipment，powersupplycapacityandsoon.InsitureactivepowercompensationandthusimprovethepowerfactoroftheEnergyConservationhasextremelyimportantsignificance.ThechoiceofmethodofcompensationCompensationforreactivepowercompensationisdividedintocentralizedanddecentralizedcompensationforthreekindsofcompensationandinsitu.Focusoncompensation，thatis，highandlowvoltagepowerdistributionsetupbyseveralgroupswithinthecapacitor，capacitorconnectedtothepowerdistributionbus，thecompensationforthedistributionofpowerwithinthereactivepower，andtoreachtherequiredvalueofthetotalpowerfactorabove.Thismethodofcompensationcancompensateforhighandlowvoltagebusroutespriortothereactivepower，whichisequivalenttothereactivepowersourcetomovetheelectricitydistributioncompanies，allowinguserstopowerthesystemrequirementsforreactivepowerhasbeenreductionintheelectricitysectortoachievetherequiredpowerfactor.Andtheirdistributionwithintheenterprisebusfollowingthelineoftransformerandreactivepowercompensationcannotplayarole，thereisstillalargenumberofreactivepowerlineflowswithintheenterpriseandgeneratelosses.Dispersioncompensationisthecapacitorswereinstalledatvariousworkshopsattheswitchboard，whichwillenableinstallationofdistributiontransformerandthesubstationtotheplantlinescanbeduetoadecreaseinreactiveloadcompensationeffect.Localcompensationisthereactivepowercompensationdevicedirectlyconnectedtotheinductionmotorterminalsonthesideorintotheline.Focusoncompensationmethodsusedinthecapacityofcapacitorcompensationorin-placethanthegroupingofcompensationshouldbesmall，itsutilizationrateisevenhigherdisadvantageisthechangeindistributionhasnotbeencompensatedbythefeeders，onlylightenedtheloadreactivepowergrid.Dispersioncompensationinthewaytheutilizationofcapacitorcompensationthantheinsituhigh，sothetotalrequirementofcompensationissmallerthanthespotisaneconomicalandreasonableremedy.Reactivepowercompensationshouldfollowthe"overallplanning，rationaldistribution，classificationofcompensation，in-placebalance;focusoncompensationanddispersioncompensationcombinetospread-basedcompensation;highcompensationandlowvoltagecompensationcombinedwithlow-pressure-basedcompensation;Regulatorcombinedwithlowerlosses，downarethemainloss"principle[1].CompensationcapacitytodetermineInthepowergridinthereactivepowerconsumptionisabig，about50%ofthereactivepowerconsumedintransmission，transformationandthedevice，50%oftheconsumedelectricityusers.Inordertoreducereactivepowerconsumption，itisnecessarytoreducethereactivepowerinthegridwhereflow.Thebestwaytostartfromtheusertoincreasereactivepowercompensation，improveuserloadpowerfactor，sothatGeneratorreactivepowercanbereducedandthereductionoftransmission，transformationanddistributionequipmentinthereactivepowerconsumption，soastoachievethepurposeofreducingwearandtear[2].CompensationforreactivepowercapacityofQcfor

=Pav1C0S2=Pav1C0S2申1-1-1C0S2申2Loadchangescanbedecidedaccordingtothestaticordynamiccompensationmode.Whentheloadchangeisrelativelystable,weshouldusethestaticmethodofcompensation,whichcannotonlyreducethelinelosses,andinvestment;whentheloadchangeislarge,dynamiccompensationmethodshouldbeused,stablevoltage[3].ReducelinelossesIslocatedataratedvoltage,activepowerisconstant,duetopowerfactorchanges,thelinelossrateofchangeAP%forthe△P%二1-)2x100%cos申1- 2JAscanbeseenfromTable1toimprovethepowerfactorinloweringpowerconsumption,improvingeconomicefficiencyplaysanimportantrole.Table1Powerfactorandpowerlosspercentageofthecorrespondingdatacos.Mi0-800-850-900-951.000-60+3-7550-1755-5560-11640-6533-9841-5247-8453-1857-750-70234432-1839-345-7510-7512-LI22-1530■丸37-6743-75Ifaconstantactivepowercondition,theoriginalpowerfactorcos申1of0.59,compensatedpowerfactorcos申2of0.98,itslinelossratereductionAP%to64%.Dynamiccompensationdevice,Grouptotrackthepowercapacitorcompensation,powerfactorcanbedifferentfromthestabilityprovidedinthecontextofthepowerfactortoachieveadequatecompensationpurposes.Lines,transformercapacityincreaseLines,transformercapacityincreasedASforthe

△S=Sx△S=Sxcos申1-+

cos申Additionalcompensationdevice，mayimprovethepowerfactor，powerfactoronthebusinessofdirecteconomicbenefitisobvious.Becausethestateelectricitysystem，startingfromtherationaluseofenergy，accordingtothepowercompanytoadjustthepriceduetohighandlowvalues.Thecompensationdeviceforenterpriseandtheentirepowersystemeconomicoperationallhavesignificanteconomiceffects.ToimprovethevoltagequalityToimprovethevoltagequalityisthedynamicreactivepowercompensationequipmentinstalledaroundtheroleofplaceinthelinevoltagecompensationhasincreasedslightly.xxWheretg申1-compensationdeviceisnotinstalledbeforethe申1angletangent;tg申2-compensationequipmentinstalledafterthe申2angletangent;R,x---lineresistance，reactance.IndustrialenterprisesforthepowersystemproblemsandsolutionFig1foradiagramofpowersupplysystemsforheavymachinetoolplant.Atpresent，thetotalcapacityoftheplanttransformer17660kVA，atotalof20transformers(1#~20，#transformers)，eachtransformercapacityrangeof50~1250kVA，changingtheratioof10kV/014kV.Transformerlowvoltagesideoftheloadismainlymotor，shownintheM1，M2Mnshown.Ingeneraltherateoftransformerloadisbasicallymaintainedat28%~29%，andthemaximumloadof7000kW.HighandlowvoltagecompensationtoreplaceacombinationofhighconcentrationofcompensationFromthefigurewecanseetheplantsupplynetworkfocusedonhigh-voltagepowerfactorcompensationiscompensationthatisonlyinthehigh-voltagebusbar10kVsubstationcapacitorbanksonthepick，whilethelowpressurehasnottakenanycompensationmeasures.Thefixedcapacitorcompensationmethodtherehavebeencompensationorduecompensation，andrightbelowthesecondpowersupplybuspower

factorcompensationcircuitdoesnotwork.Asthelowpowerfactorcausedbythelinelossesandtransformerequipmentisabigloss,socompensationasfaraspossiblewhengrading,installationofcapacitorsneartheload.Thereforeproposedthatthehighsidetofocuscompensationanddispersioncompensationforlow-voltagesideofacombinationofmethodofcompensationt■

t■

nrovb

HTA9](]*Figure1PowerSupplySystemofaHeavyMachineToolPlantdiagramTochangethepowersupplyasmuchaspossibletoavoidthe"bighorse-drawncart"phenomenonInmakingourselection,weshouldconsiderleavingacertainmargin,topreventheavydamagetoequipmentwhen,somostofthetimecausedbyequipment,andsevereunderrununderruntheformationofthe"bighorse-drawncart"Run.Astheplantloadfactorofthetransformerisbasically28%?29%,andshowsthetransformercapacityistoolarge,transformercapacitycannotbefullyutilized,notonlyawasteofinvestmentinequipmenthasincreasedthepowerloss.Rationalchoicebythetransformercapacityandelectricalequipmenttoreduceorlimitthelight-loadornoloadtimetopreventthe"bighorse-drawncart"phenomenon.Toavoidtheno-loadoperationofequipmentAtpresent,theplantisrunningaseriousloadofsomeequipment.Improvingthepowerfactor,thefirstconsiderationshouldbegivenareasonableruntheequipmenttoimprovepowerfactorofpowerthedeviceitself.TheplantmainloadisACmotor,itspowerfactorloadwithitchange,motoridling,thepowerfactorofabout0.1?0.3betweentheratedloadat0.8?0.85betweenthemotorandthusshouldbemadenearthe.ratedloadstaterun.Weshouldimprovethemotorpowerfactor,thesimplestwayistousecapacitorsandelectricmotorsinparallel,sotoavoidtheno-loadoperationdeviceistoimprovethepowerfactorequipment,animportantway.EconomicBenefitAnalysisTothefactorypowersupplysystemintwo#transformers,forexample,installationofcapacitorsinthelowvoltageside,sothathigh-pressuresideoftheplanttofocusoncompensationanddispersioncompensationcombinationoflow-voltagesideofacompensationformula,showninFigure2.Graph2#transformercapacityof800kVA,modelS9-800/10,ratedcopperlossforthe715kW,transmissionlinemodelYJV22.Getpriceof0.55yuan/kWh.Thepowerfactorbythecompensationpriorto0.59tocompensateforpost-0.98,Table2istheuseofmeasuringinstrumentsmeasuredinthefieldoftransformersecondarysiderun-timedataareanalyzedbycalculatingthelossofreactivepowercompensationreducedenergyefficiency.Table2transformersecondary-siderun-timedatatable

電矗止 鋤功功率 為無功功車h h 日倆 QEr1425.L餌57301108.11118.2520.616—■斗?UMU93.W131.17720.58J■■J-422.54216275.f300.2JOG.36151.3J70.575442fi.94?2.8315.]S43.4123.9issm0.M7410J422.5歸9126.120.679.■4^.4421j仍7303.69745149.13810.M77■4^.5Ml235250.2U0.5S160.534s■^6.2251.1270.7嘰儲151J0760.539422.S+252662血肖102.45151：760.5611G42122919317.4112960.65硼1228142<B2274.92300.92144.L52T0J89Theenergy-savinghigh-voltagepowerlinesThroughouttheyeartosaveelectricityAW=aPhelectricpowerlines,electricpowerlines,Where△Pl-theincreaseini( 、c△P=312R1-cos申 11{cosP丿Thenumberofannualoperatinghours,whichever5000h.Thecalculationofannualenergysavings162217kW.h,withinoneyeartoreduceelectricityconsumptioncosts81.92millionyuan.Transformer-savingThelossofmaintransformerironlossandcopperloss.Transformersecondarysidetoimprovethepowerfactor,canreducethetotalloadcurrent,therebyreducingthecopperloss.TransformercopperlossoftheyeartosaveenergyAW=(APCul-APCu2)hwhereAPCul-compensationfortheactualrun-timebeforethetransformercopperlossofelectric=△PCuN=△PCuN△PCu1APCu2-compensatedtransformercopperlossofelectricpower,

△PCu2△PCu2=△PCuN1COS申 1.cos申2Thecalculationofannualenergysavings3150kWh,withinayeartosaveelectricitytransformercopperlossof173,518yuan.PowerFactorAdjustmenttariffUserswithinayeartoreducespendingmorethanthelowpowerfactorpenalty:800x0.589x5000x0.55x17.22%(increaserate)=221.31millionyuanofcompensationwithinoneyearaftertheusersgetthepowerfactorbonus:800x0.589x5000x0.55x2.7%(reducedrate)3.15milliontotalof251.81millionyuanfromthetwoabovecalculationswecanseeanoverallincreasewithinoneyearofnetincome341.73millionyuan,accordingtothecapacityrequiredtocompensateforequipmentinvestment27.15millionyuan, 9monthswillbeabletorecovertheirinvestments.Thisshowsthattheplantfoundryforthespecificcircumstancesofthetransformersecondarysidecompensationforuseofdecentralizedapproachtoreactivepowercompensationisfeasibleandcanachievelong-termandsignificanteconomiceffects.10kv無功補償摘自一一《電力系統(tǒng)分析和設(shè)計》摘要提升工業(yè)企業(yè)用電效率、節(jié)約電能的重要手段和方法就是改善電能消耗的功率因數(shù)。本文通過分析理論和應(yīng)用實例說明了企業(yè)用電的無功功率補償?shù)囊饬x和作用，就工業(yè)企業(yè)電力供應(yīng)系統(tǒng)當前存在的問題，提出了改進建議和措施。1引言在工業(yè)企業(yè)中，電氣設(shè)備中絕大多數(shù)都是感性負載，這些設(shè)備在運行過程中吸收大量的無功功率。無功功率的增加使得供電系統(tǒng)的功率因數(shù)降低，從而出現(xiàn)系統(tǒng)電壓下降、電氣設(shè)備得不到充分利用、增加線路損耗以及降低供電設(shè)備的供電能力等情況。因此，就地進行無功補償，提高功率因數(shù)對節(jié)能具有非常重要的意義。補償方式的選擇無功補償分為集中補償、分散補償和就地補償三種。集中補償，即在高壓和低壓配電所內(nèi)設(shè)置若干組電容器，電容器接在配電母線上，補償該配電所供電范圍內(nèi)的無功功率，并使總功率因數(shù)達到規(guī)定值之上。這種補償方式只能補償高壓和低壓母線之前線路上的無功功率，它們相當于把無功功率源移到用電企業(yè)的配電所，使用戶對供電系統(tǒng)要求的無功功率有所減少，達到供電部門所要求的功率因數(shù)。而它們對配電母線以下的企業(yè)內(nèi)部的變壓器和線路的無功功率不能起到補償作用，仍有大量的無功功率在企業(yè)內(nèi)部線路上流動并產(chǎn)生損耗。分散補償是將電容器組分別安裝在各個車間的配電盤處，這種安裝方式可以使配電變壓器以及變電所至車間的線路都可以由于無功負荷的減少而獲得補償效果。就地補償是把無功補償器直接接在異步電動機旁或進線端子上。集中補償方式所用電容器組的容量較分組補償或就地補償要小，它的利用率則更高，缺點是對變、配電所各饋線并未得到補償，僅減輕了電網(wǎng)的無功負荷。分散補償方式中的電容器組的利用率比就地補償高，因此總需要量較就地補償要小，是一種經(jīng)濟合理的補償方式。無功補償應(yīng)遵循“全面規(guī)劃，合理布局，分級補償，就地平衡;集中補償與分散補償相結(jié)合，以分散補償為主；高壓補償與低壓補償相結(jié)合，以

低壓補償為主；調(diào)壓與降損相結(jié)合，以降損為主”的原則。補償容量的確定在電網(wǎng)中的無功功率消耗較大時，大約50%的無功功率消耗在輸、變、設(shè)備上，50%消耗在電力用戶上。為了減少無功功率消耗，就必須減少無功功率在電網(wǎng)里的流動。最好的辦法從用戶開始增加無功補償，提高用戶負荷的功率因數(shù)，這樣可以減少發(fā)電機無功出力和減少輸、變、配電設(shè)備中的無功電力消耗，從而達到降低損耗的目的。補償?shù)臒o功功率容量Q為c=Pav=Pav-1-1C0S2申11-11C0S2申12式中P—最大負荷日平均有功功率；cosP—未裝設(shè)補償裝置前的功率因數(shù)實測av1值；cosP—裝設(shè)補償裝置后所達到的功率因數(shù)值。2無功補償裝置的作用可以根據(jù)負荷變化情況決定采用靜態(tài)還是動態(tài)補償方式。當負荷變化較為平穩(wěn)時，應(yīng)采用靜態(tài)補償方式，這不僅能較好地降低線路損耗，而且投資少;當負荷變化較大時，應(yīng)采用動態(tài)補償方式，穩(wěn)定電壓。降低線損設(shè)在某一額定電壓下，有功功率恒定不變，由于功率因數(shù)變化，其線路損耗變化率AP%為△P%二1-（^0^）2X100%

cos申2從表4.1中可以看出提高功率因數(shù)對于降低電能損耗，提高經(jīng)濟效益具有十分重要的作用。表4.1功率因數(shù)與有功損耗百分率的對應(yīng)數(shù)據(jù)COS.扌10OS^20.￡00.850.900.951.000-604芬7550-1755-5560-116斗65妙9S斗］1?52斗S41呂0-702呂4432-1839-545-7517512-1122-155637-6743-75若在恒定有功功率條件下，原有的功率因數(shù)cos申為0?60,補償后的功率因數(shù)icosP為1,0時，其線損率降低AP%為64%。采用動態(tài)補償裝置，將電力電容器分組2跟蹤補償，則可由原來不同的功率因數(shù)穩(wěn)定在所規(guī)定的功率因數(shù)范圍內(nèi)，達到充分補償?shù)哪康摹?.2線路、變壓器的增容線路、變壓器的增容量AS為(、Q2[COS申

△S=Sx1— 1-.cos申丿后添加的補償手段，提高功率因數(shù)，功率因數(shù)直接的經(jīng)濟利益的企業(yè)是顯而易見的。由于關(guān)稅制度的國家，從能源的合理利用出發(fā)，功率因素值根據(jù)企業(yè)調(diào)整價格水平。這種補償裝置是針對電力系統(tǒng)的整個企業(yè)的經(jīng)濟運行，并有顯著的經(jīng)濟效益。4.3改善電壓質(zhì)量改善電壓質(zhì)量是安裝前和安裝動態(tài)無功補償裝置后，具有增加的線電壓補償位置的作用?！鱑=U1—U2X100%=tgP2XQ1 R+吧X式中tgp—未裝設(shè)補償裝置前p角的正切;11tgp—裝設(shè)補償裝置后p角的正切;22R、x—線路的電阻、電抗。

5工業(yè)企業(yè)供用電系統(tǒng)存在的問題與解決措施圖1為某重型機床廠供電系統(tǒng)示意圖。目前，該廠變壓器總?cè)萘繛?7660kVA，共有20臺變壓器（1#?20#變壓器），每臺變壓器的容量范圍為50?1250kVA，變比為10kV/014kV。變壓器低壓側(cè)負載主要為電動機，如圖中Ml、M2Mn所示。一般情況變壓器負載率基本上維持在28%?29%之間，最大負載時為7000kW。5.1采用高、低壓相結(jié)合的補償方式取代高壓集中補償從圖中的功率因數(shù)補償網(wǎng)絡(luò)是種植僅接受在高壓變電站10kV母線高壓集中補償電力電容器組中可以看出，在低氣壓，但沒有采取任何補償措施。這樣一來就會有一個固定電容補償?shù)那闆r下過補償或欠補償，第二個總線功率因數(shù)補償下面的電源線不起作用。線和因造成功率因數(shù)低的損耗變電站設(shè)備損壞是很大的，所以賠償應(yīng)盡量分級，靠近的安裝電容負載。因此，建議關(guān)注的賠償?shù)暮喜ρa償?shù)母邆?cè)和低側(cè)分散的方式。t■?出nTAerbt■?出nTAerb圖5.1某重型機床廠供電系統(tǒng)示意圖5.2改變供電方式，盡可能避免“大馬拉小車”的現(xiàn)象當設(shè)備選型，考慮留下一些能力，以防止損壞設(shè)備過載時，所以大部分的時間，造成設(shè)備的嚴重不足不足形成了“大馬拉小車”的運行。自植物的負載率基本上變壓器28％29％之間，這表明大容量變壓