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基于PLC的污水处理系统外文翻译

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昆明理工大学大学毕业设计英文资料与中文翻译专业班级:自动化112班学生姓名:何荣法指导教师:张光辉学院:信息工程与自动化学院2015年5月\nApplicationofcontrolsystemonthebaseofPLCinsewagetreatmentThepaperintroducesadistributedcontrolsystemofsewagetreatment,andthecoreofthesystemisPLC.Thestructureofthecontrolsystem,theassignmentandimplementationofthetasks,thecontrolschemeandthedesignconceptofprogramareexpounded.Thewayofcentralmonitoringmanagementanddispersingcontrolisusedbythecontrolsystem;thelong一distancecontrolandmonitoringoffieldequipmentareunchargedoftheuppercomputer;thesoftwareprogramofdesignsusesIntouch7.0.Thespecifictechnology,equipment,thecontrollingofmainparameterandseveralrunningdataareunchargedofthePLCstations,andthesoftwareprogramofdesignsusesConcept2.2XLwithonlinetrackingandoutlinesimulating.MB+netisadoptedbythecommunicationbetweentheuppercomputerandthePLCstations,withitssimplybuildingnet,quicklyrunningandstablecommunication.TheautomaticcontrolofPLChasbeensuccessfullycompletedinsewagetreatment,whichhasimprovedtheoperationefficiencyandmanagementlevelofsewagetreatmentequipmentIntroducedtotakePLCasthedistributetypecontrolsystemofcoreinthewastewatertreatmentsystemofapply.Concretelydescribedthestructure,missionofthecontrolsystemanallotmentandcarryout,thewayofcontrolandthethoughtoftheprogramdesign.Thewaycontrolledtheconcentrationmonitorofthesystemadoptionamanagementandscatteredacontrol,theplaceofhonormachineberesponsibleforthespotthelongrangeoftheequipmentscontrolandsurveillance,softwareadoptionIntouch7.0drawup.ThePLCnativestationisresponsiblefortotheconcretecraft,equipmentandismainlycontrolledparametertocarryoncontrolandcollectvariousmovementdata,theprogramdesignadoptionhaveon-linefollowwithoff-lineimitatetheConceptoftruefunction2.2XLsoftware.PlaceofhonormachineandofthePLCadoptionsetthenetbequicklysimpleandcirculatespeed,correspondbyletterthestabilitystrongMBnet.ThewholecontrolsystemsuccessfullysolvedthePLCcontrolsaproblemintheautomationwithinwastewatertreatmentandraisedawastewatertreatmentequipmentstocirculateanefficiencyandmanagelevel.Recently,forcarryingouthighquality,lowconsume,stabledependablemovement.Domesticandinternationalmanywastewatertreatmentfactories\nadoptedamodernforerunnertocontroltechniqueandcalculatortechniqueandconstitutecalculatordirect,controlthus,managesystem.Makesystemexcellenttoturnmovement.Buttheprogrammablelogiccontroller(PLC)thentakemicroprocessorascore.Synthesizethecalculatortechniqueautomaticallycontrolstechniqueandcorrespondencetechniquebutdevelopsofakindofnewandingeneraluseautomaticcontroldevice.Havestructuresimple,functionsuperior,dependablesexGao,workproperlywordsingeneraluse,beeasytoplaitdistance,usageconvenienceetc.advantageetc.ThesilverCitythefirstwastewatertreatmentfactoryadoptedaSBRcraftandtakePLCasthecontrolsystemofcore,dayafterhandlingthesewage10×104ttheprocessingofreachmarksewagecanusedforanagricultureirrigation.1ControlsystemstructureControlthewayof"concentrationmonitormanagement,scatteracontrol"ofthesystemadoption.Theemulationhold,placeofhonormachine,gatheralinemachine,printertoBelocatedonmediumcontrolroom,twosetPLCsarelocatedoncontrolthespot.Adoptthiskindofstructurecanmaketheinformationintheproductionlinecancentralizedmanagementwithcarryoutwholeoperation,managementwithexcellentturn.Alsomaketocontroldangerousdispersioninthemeantime,raisethesystemcredibility.1.1TheuppercomputersMediumcontroltwocalculatoradoptionPIIclassworksofroomtocontrolmachine,circulatetheoperatesystemofWindowsNT.Theplaceofhonormachineberesponsibleforonthesceneestablisheachlongrangecontrol(full-automaticcontrol,automaticcontrol,ordertomoveacontrol)withsurveillance,makeuseofIntouch7.0engineeringsoftwarepackagesprovideagoodpersonmachinedialogueboundarybutobtainconcerningparameterandequipmentsappearanceinformationfromthePLCbysearchingaway,keepaviewmanifestationtocomeoutontheCRTbygoodsketchtype,printanecessarydatainthemeantimeandbeprovidedforlordtocontrolandmanagerinstructionproduce.Superviseandcontrolboundarybutincludethesystemtotaldiagram,systemcentdiagram,imitatethequantitygeneralchart,parameteraconstitution,reporttothepoliceawindow,historytrendandregisterawindowetc.boundarybut.Inthesystemtotaldiagram,circulatethepersonnelcankeepwatchonsignals,suchasallmovementappearances,equipmentstroubleandliquidwhichcontrolanequipmentanddischargeetc.Operateapersonnel\ninthesystemthecentthediagramcancarryonasinglemachinepointtomovetocirculateanoperationtoallcontrolequipment,becomethesetautomaticallycirculateoperationorthewholefactoriesfull-automaticoperationcombinesurveillance.Inthemeantimeplaceofhonormachine2anddoaplaitdistanceamachine.Mediumcontrolroomtoestablishanotheraninsettypeemulationtohold,isbeenonecontrolbytheplaceofhonormachine,inordertokeepthecraftprocessoftheviewmanifestationwholefactoryandmainparametervalue.1.2ThePLCstandAccordingtowastewatertreatmentoftwopart,thespotthelongrangeoftheequipmentsthecontroloutputandthespotthesignalcollecttocontrolastationcompletionfromtwoPLCwoodground.PLC1nativecontrolstationcontrolthespacegrid,sewagepromoteapumphouse,Puspirittosinksandpond'setc.toprepareaprocessingpart.ThePLC2nativecontrolstationcontrolsdirtymiretodehydrate,presstofiltermachineetc.department..PLC3nativecontrolstationcontrolSBRlivingcreatureprocessingpart.Moreover,theonthespotnativecontrolstationiseachtoestablishanoperationterminaltoestablisheach,beresponsibleforatnativetoestablisheachcontrolonthescene.(automaticcontrol,ordertomoveacontrol)Thespotiseachthephysicalparameterthatthesupervisionorderandincludewaterlevel,temperature,dischargeandturnsoon,electriccurrent'setc.imitatequantity,fromtoinresponsetoofanappearancespreadafeelingmachineorchangetosendtoamachineexaminationtocomeoutandchangeintotheelectriccurrentsignalofthe4~20mA,throughshieldinsidethePLCthattheelectriccablesendstoeachstaturessystem,fromthePLCpicksupapeoplethroughvariousmoldpiecesampletelecommunicationnumber.Same,imitatequantitycontrolthesignalsendtoperformanceorganizationbythe4~20mAelectriccurrentformafterbeingoutputbythePLC,controlperformanceorganizationofaction.TheQuantumseriesPLCofSchneidercompanyissatisfyliberalof,accordingtostandardofnetworkconjunctionandthespottotallineconjunctionetc.applicationthetechniqueprovidedvariousnetworkachoice,supportModbus,Mod-busPlus(MB+),thelongrangeI/0,TCP/IPetc.networkconjunction,havestrongerandvivid.Therefore,thewastewatertreatmentisconvenienttoarriveofthePLCchoosetheseriesofMOofuseSchneider.1.3CorrespondencesMBagreementistheMcompanyreleaseofanopentypeoftheadoption\nIEEE802.4correspondbyletter5agreementsthespottotallineofcardagreement.MBthenetworktogetherothernetworkscomparetohaveasetofnetsimple,theinvestmentbelittle,networkspeedquick,correspondencethestabilitystrongetc.characteristics,itmakecalculator,controllerandotherdatasourcesthroughanusagedoublewringlineorfiberopticcableBeabodytotogethercarryoncorrespondenceatthewholenetworktop.ButtheCPUmoldpieceoftheMQseriesPLCimplyMBcorrespondence,thereforecorrespondbyletteranetworktochoosetouseMBnetwork.Mediumcontroltwomachine,twocontrolstationswithnativePLCofroomtopassMBthenetworklinktogether.ThePLCCPUmoldpiecepassesMBcorrespondenceandtwomachinescarryondatacommutationandcollecttheplaceofhonorsupervisionvariousoperationinstructionofthesystemandthespottheexaminationsignalanddata,throughanalysishandle,passexportationmoldpiecetocontrolobjectoutputcontrolsignal;Inthemeantime,thePLCpassesMBnetupwardthemachinereturntovariousdata,placeofhonormachinelogarithmsaccordingtocarryonanoperationprocessing,showvarioussignalandprintvariousstatement.2ThedesignofPLCcontrolprogramThesystemhasfourkindsofcontrolmethods:Thenativehandmovesacontrol,singlesetequipmentspointmovesacontrol,becomeaset,theequipmentsautomaticallycontrols,thewholefactoryequipmentfull-automaticcontrol.Twokindsofex-withgeneralmethodsatestablisheachadjusttotryormaintainusage,thesystemismainlycirculatewithfull-automaticcontrol.Underthiskindofway,alleachkindofequipmentfromPLCaccordingtoinadvancedrawupofprocedureautocontrol,don'tneedtooperateapersonnelanintervention.VariousspotdataspreadsahighestmachinethroughaPLC,comeoutintheplaceofhonoronboarddescriptionandmakethecraft,equipmentsmovementofwholefactoriesgetanoverallcontrol.ThelivingcreatureprocessingpartofthePLC3stationcontrolisthewholewastewatertreatmentofkeypart,belimitedbyspace,onlywiththePLC3standofprogramdesignforexample.2.1ProcessofcontrolThePLC3stationswereusedtocontroltogetintoPuspiritfromsewage,thepondiseverywheresewagerunoffPuaftermanagespiritthewholeprocessofthepond.Includeturnofsequenceandtime-switchmoderatebreezesmachineofcontrolvariousvalve,pump,breezemachinetosoonregulateetc.inthisprocess.ThePuspiritpondisthecoreofwastewatertreatmenttoconstructathing,sewageistocome\nandgothroughamicrobiallivingcreatureoxygenationinthepondinadditiontoorganicmatter,theprocessingeffectofcontenttosewageoftheoxygeninwateristogotoapassimportant.RequestaccordingtotheSBRcraft,thedeliquescenceoxygeninthePuspiritpondcontentusuallycontrolswithinthescopeof1~3mgs/LandannoyastageendtofuseanoxygencontentinthePushouldbenotoverthe2mgs/L.ContaintheoxygenoncemeasuredloworleadGao,allwillinfluenceafluidmatterquantity.Handle4setsofthe10×104ttheSBRof8pondmodestorespondpondtotheday,eachonerespondsthatthepondgotogetherwithapedestalfromchangePinmachinecontrolofbreezemachine,usedforannoyingpondPuspirittobyturnprovideoxygentowardtwoPus.Establish4piecesofdeliquescenceoxygentestinstrumentsinthedifferentlocationofeachPuspiritpond,measurecontainofsewageamountofoxygeninpond,thePLCseparatesa5minestoexamineadeliquescenceoxygeninaPuspiritpondvalueeachtime,accordingtofuseoxygenofaveragevaluetocontrolbreezemachinetoturnsoon.Iffuseoxygenlowlimitatthebottomoftheenactment,thefrequencymodulationbreezemachineturnstosoonincrease5%;IffuseoxygenGaowhilesetupperlimit,thefrequencymodulationbreezemachineturnstosoonlower5%.So,carriedoutPuspiritpondtoprovideautomaticallyregulateoftheamountofoxygen,sinceavoidedunnecessaryenergyloss,againexcellentturnedmovementcraft.2.2ThedesignofPLCprogramTheadoptiveplaitdistancesoftwareisaConcept2.2XLs.ConceptisaccordingtoundertheWindowsofthePLCplaitdistancetool,havegoodcustomer'sinterface,andhaveon-linefollowandoff-lineimitatetruefunction.ThecontrolprocedureofPLC3stationsisdividedintofiveproceduremoldpiece.(1)Publicmoldpiecesofprocedureuse-includeabeginningtostarttoturnpart,hourcentsecondetc.askpulseunit,SBRtorespondaperiodenactment,fuseoxygenenactment...etc..(2)Ordercontrolmoldpiecesoftheswitchquantity-thecoordinationcontrolreporttothepoliceofcirculateandrelatedbreakdownofequipment,suchaseachvalve,pumpandbreezemachine...etc..TheenterofSBRpondspiritvalve,enterwatervalve,refluxpump,surplusdirtymirepumpfromPLCaccordingtothecraftofthewastewatertreatmentperiodtimesegmentcontrol,watervalvefromPLCaccordingtocrafttimeandsupervoiceliquidthemeasuredvalueoftheinstrumenttocontrol.\n(3)Protectionmoldpiecesoftheoff-power-systempowerfailureafter,thePLCsavesallappearancelocksandmakeaftertreatingtoaddanelectricityPLCinstaurationkeepoftheappearancecontinuetocirculate.(4)Moldpiecesofcorrespondences-usetocompletePLCandvariousdatatransmissionofplaceofhonormachine.(5)Fuseanoxygenvaluetoautomaticallyregulateamoldpiece-accordingtofuseanoxygenvaluetoregulatebreezemachinetoturnsoonandreporttothepoliceofrelatedbreakdown.Thetargetwhichregulatestoturnsoonpromisesthebeworthofdeliquescenceoxygenas2mgs/LinthewholePuspiritperiod.Adoptivecontrolstrategyisasfollows:ThePuspiritperiodbeginning,thebreezemachineattopspeedmovementattainsa2mgs/Linshortlyofthehouraskbymakingdeliquescenceoxygenandtake5minesasaperiodtoexaminedeliquescenceoxygentobeworthinthemeantime.Whenfuseanoxygenvaluebigatthe2mgs/L,thebreezemachineturnstosoondescend5%;Whenfuseanoxygenvaluesmallatthe2mgs/L,thebreezemachineturnstosoonrise5%.Ifthebreezemachineturnstosoonrisetoallowoftallestturnsoon,fuseanoxygenvaluereturnsmallthenmaintaintallesttoturnsoonatthe2mgs/L.ThiskindofcircumstancemayannoythelastphaseofperiodtoappearinthePu,butalsowillnotclearlyinfluencewastewatertreatmentquality.SuperviseandcontrolanexportationelectriccurrentofchangethePinmachinevalueatanytimeinthePuthespiritofthewholeperiod,makeitnotexceedchangethesumofPinmachinesettleavalue.Ifmeetasurprisedcircumstancetomaketooutputelectriccurrentexceedwhenthesumsettlevalue,immediatelylowerbreezemachinetoturnsoon.Ifthebreezemachineturnstosoondeclinetoallowoflowestturnsoon,outputelectriccurrenttoreturnexceedthesumsettleavalue,thenstopbreezemachineandsendouttoreporttothepolicesignalinthemeantimeAlongwithautomaticcontroltechnicaldevelopment,theUNITANKcraftmoreandmoregetsextensivelyapplied.Regardexperienceasprinciplecurrently,useDO,time,dischargeasacraftcontrolparameter,adjustthePuspiritcirculateofmachineandlineupmiretheetc.lackaccuratemathematicsmodeltocarryouttheautomaticcontrolofhigherlayerofSBRmethodfortime.SomeoneonceputforwardtooktheCODorthedoasparameterofmistycontrolofthought.TheresearchdirectionoftheautomaticcontrolofSBRmethodmainlyistolookforseveralcontrolparametersfromnowon,sincecanreflectintowateroffluidmatterwaterquantityvarietyandreactionprocessinofdeclineasolutioncircumstance,andthencandoforthe\ncalculatorcontrolparameter.ThePLCgathersinproperordercontrolandprocesstocontrolattheintegralwholeandhavedependablesexGao,usageconvenience,vivid,setnetsimpleofthecharacteristicsbetheemollienttoolofthesmallscaleindustrialautomationintherealization.Inthewastewatertreatment,accordingtoPLCcontrolsystematsolidsex,credibility,accuratesexetc.dintabutsatisfiedadesignarequest,promisedwastewatertreatmentofsmoothlyprogress.BecauseofInternetfastdevelopment,hopecancometovisittoaskwastewatertreatmentfactorythroughanInternetoffromcontrolsystem,theInternetwhichneededtoinputuser'snameandpasswordandthencancarryoutlongrangecametocarriedonacontroltotheequipmentofwholefactories.TransportthesewagedataofwastewatertreatmentfactorytothenationalenvironmentalprotectionbureauthroughanInternetinthemeantimecityenvironmentalprotectionbureauperhaps,forthepurposeoftheBuclassmanagementofsectiontowastewatertreatmentfactory.\n基于PLC的控制系统在污水处理中的应用介绍了以PLC为核心的分布式控制系统在污水处理系统中的应用。具体叙述了控制系统的结构、任务分配及实现、控制方式和程序设计思想.控制系统采用集中监测管理、分散控制的方式,上位机负责现场设备的远程控制和监视,软件采用Intouch7.0编制。PLC本地站负责对具体的工艺、设备、主要被控参数进行控制及采集各种运行数据,程序设计采用具有在线跟踪和离线仿真功能的Concept2.2XL软件。上位机与PLC之间采用组网简单、运行速度快、通信稳定性强的MB+网。整个控制系统成功地解决了PLC在污水处理中的自动化控制问题,提高了污水处理设备运行效率和管理水平。近年来,为了实现高质量、低消耗、稳定可靠的运行。国内外许多污水处理厂采用了现代先进控制技术和计算机技术,从而构成计算机监督、控制、管理系统.使系统优化运行。而可编程逻辑控制器(PLC)则是以微处理器为核心。综合了计算机技术自动控制技术和通信技术而发展起来的一种新型、通用的自动控制装置。具有结构简单、性能优越、可靠性高、灵话通用、易于编程、使用方便等优点等。银川市第一污水处理厂采用了SBR工艺及以PLC为核心的控制系统,日处理污水10x104t处理后的达标污水可用于农业灌溉。1控制系统结构控制系统采用“集中监测管理,分散控制”的方式。模拟屏、上位机、集线器、打印机位于中控室,二台PLC位于控制现场。采用这种结构可使生产过程中的信息能够集中管理,以实现整体操作、管理和优化。同时,也使得控制危险分散,提高系统可靠性。1.1上位机中控室的两台上位计算机采用PII级工控机,运行WindowsNT操作系统。上位机负责现场设各的远程控制(全自动控制、自动控制、点动控制)和监视,利用Intouch7.0工程软件包提供良好的人机对话界而,以查询方式从PLC获取有关参数和设备状态信息,以棒图形式在CRT\n上直观显示出来,同时打印必要的数据,供主控及管理人员指导生产。监控界而包括系统总图、系统分图、模拟量一览表、参数设置、报警窗、历史趋势、登录窗等界而.在系统总图里,运行人员能够监视所有控制设备的运行状态、设备事故及液位、流量等信号.在系统分图里,操作人员能够对所有控制设备进行单机点动运行操作、成组自动运行操作或全厂全自动操作并监视。同时上位机2兼做编程器.中控室另设置一个镶嵌式模拟屏,由上位机1控制,用以直观显示全厂工艺流程及主要参数值。1.2PLC站根据污水处理的二部分,现场设备的远程控制输出和现场信号采集由二个PLC木地控制站完成。PLC1本地控制站控制格栅、污水提升泵房、曝气沉砂池等预处理部分。PLC2本地控制站控制污泥脱水、压滤机等部。PLC3本地控制站控制SBR生物处理部分.另外,在现场本地控制站各设1台操作终端设各,负责在本地对现场设各的控制(自动控制、点动控制)。现场各个监控点的物理参数,包括水位、温度、流量、转速、电流等模拟量,由对应的一次仪表传感器或变送器检测出来并转变为4~20mA电流信号,经屏蔽电缆送到各个子系统的PLC内,由PLC通过各种模块接口采样电信号。同样,模拟量控制信号由PLC输出后以4~20mA电流形式送到执行机构,控制执行机构的动作。施耐德公司的MQ系列PLC为满足开放的、基于标准的网络连接和现场总线连接等应用技术提供了多种网络选择,支持Modbus,Mod-busPlus(MB+),远程I/0,TCP/IP等网络连接,具有较强的灵活性。因此,污水处理中用到的PLC选用施耐德的MQ系列。1.3通信MB+协议是一个开放式的采用IEEE802.4令牌协议的现场总线通信5协议。MB+网络同其他网络相比具有组网简单、投资少、网络速度快、通信稳定性强等特点,它使计算机、控制器和其他数据源通过使用双绞线或光缆在整个网络上作为同位体进行通信。而MQ系列PLC的CPU模块含有MB+通信口,因此,通信网络选用MB+网络.中控室的两台上位机、二个PLC本地控制站通过MB+网络连接在一起。PLC的CPU模块通过MB+通信口与两台上位机进行数据交换,采集上位监控系统的各种操作指令及现场检测信号和数据,经过分析处理,通过输出模块向控制对象输出控制信号;同时,PLC通过MB+网向上位机返回各种数据,上位机对数据进行运算处理,显示各种信号和打印各种报表。2PLC控制程序设计系统有四种控制方式:本地手动控制,单一台设备点动控制,成组设备自动控制,全厂设备全自动控制。前二种方式一般只在设各调试或维修时使用,系统主要以全自动控制方式运行。在这种方式下,所有各类设备都由PLC按照预先编制的程序自动控制,不需要操作人员干预.各种现场数据通过PLC传至上位机,在上位机上描绘出来,使全厂的工艺、设备运行得到全面的控制。PLC3站控制的生物处理部分是整个污水处理的关键部分,限于篇幅,仅以PLC3站的程序设计为例。\n2.1控制过程PLC3站用来控制从污水进入曝气池到处理后的污水流出曝气池的整个过程。在这个过程中,包括控制各种阀、泵、风机的顺序及定时开关和风机的转速调节等。曝气池是污水处理的核心构筑物,污水在池中是通过微生物的生物氧化作用来去除有机物的,水中氧的含量对污水的处理效果是至关重要的。根据SBR工艺要求,曝气池内的溶解氧含量通常控制在1~3mg/L范围内,在曝气阶段末溶解氧含量应不超过2mg/L.含氧量过低或过高,均会影响出水质量。对日处理10x104t的4组8池模式的SBR反应池,每组反应池配一台由变频器控制的风机,用于向两个曝气池轮流曝气供氧。在每个曝气池的不同地点设4块溶解氧测试仪,测量池中污水的含氧量,PLC每隔5min检测一次曝气池内的溶解氧值,根据溶解氧的平均值来控制风机转速。若溶解氧低于设定下限时,调频风机转速增加5%;若溶解氧高于设定上限时,调频风机转速降低5%.这样,就实现了曝气池供氧量的自动调节,既避免了不必要的能源损失,又优化了运行工艺。2.2PLC程序设计采用的编程软件是Concept2.2XL。Concept是基于Windows下的PLC编程工具,具有良好的用户界面,并具有在线跟踪及离线仿真功能。PLC3站的控制程序分为五个程序模块。(1)公用程序模块——包括初始化部分、时分秒等时问脉冲单元、SBR反应周期设定、溶解氧设定等。(2)开关量顺序控制模块——协调控制各个阀、泵、风机等设备的运行及相关故障的报警。SBR池的进气阀、进水阀、回流泵、剩余污泥泵由PLC根据污水处理周期的工艺时间段控制,出水阀由PLC根据工艺时间和超声液位仪的测量值来控制。(3)断电保护模块——系统断电后,PLC将所有状态锁存,待加电后使PLC恢复所保持的状态继续运行。(4)通信模块——用来完成PLC与上位机的各种数据传送。(5)溶解氧值自动调节模块——根据溶解氧值调节风机转速以及相关故障的报警。调节转速的目标是在整个曝气周期中,保证溶解氧的值为2mg/L.采用的控制策略如下:曝气周期开始,风机以全速运行,以使溶解氧在较短的时问内达到2mg/L,同时以5min为周期检测溶解氧值。当溶解氧值大于2mg/L时,风机转速下降5%;当溶解氧值小于2mg/L时,风机转速上升5%.如果风机转速升到允许的最高转速时,溶解氧值还小于2mg/L,则维持最高转速。这种情况有可能在曝气周期的末期出现,但并不会明显地影响污水处理质量。\n在曝气的整个周期内,随时监控变频器的输出电流值,使其不超过变频器的额定值。如遇到意外情况使输出电流超过额定值时,立即降低风机转速。如果风机转速降到允许的最低转速时,输出电流还超过额定值,则停风机,同时发出报警信号。随着自动控制技术的发展,UNITANK工艺越来越得到广泛应用。目前以经验为主,以DO、时间、流量作为工艺控制参数,来调整曝气机的运行及排泥时间等,缺乏准确的数学模型来实现SBR法的更高层次的自动控制。有人曾提出以COD或DO为参数的模糊控制的思想。今后SBR法的自动控制的研究方向主要是寻找多个控制参数,既能反映进水的水质水量变化及反应过程中的降解情况,又能作为计算机控制参数。PLC集顺序控制和过程控制于一体,具有可靠性高,使用方便、灵活,组网简单的特点,是实现中小规模工业自动化的有力工具。在污水处理中,基于PLC的控制系统在实时性、可靠性、精确性等力一而满足了设计要求,保证了污水处理的顺利进行。由于Internet的快速发展,希望能够通过Internet来访问污水处理厂的自控系统,只需要输入用户名和密码便可实现远程的Internet来对全厂的设备进行控制。同时通过Internet将污水处理厂的污水数据输送到国家环保总局或者市环保局,以便卜级部门对污水处理厂的管理。