燕京理工学院机电工程学院——外文文献原稿和译文燕京理工学院YANCHINGINSTITUTEOFTECHNOLOGY外文文献原稿和译文学院:机电工程学院专业:机械工程学号:130310208姓名:张磊指导教师:王续明2017年3月燕京理工学院机电工程学院——外文文献原稿和译文外文文献原稿和译文原稿Thewatersupplysystemisthenationalproductionandlifeindispensableimportantoneannulus.Thetraditionalmethodofwatersupplyarea,waterpollution,infrastructureinvestment,butthemaindrawbackisthatwatercannotbekeptconstant,causingpartoftheequipmentcannotworknormally.VariablefrequencyspeedcontroltechnologyisanewmatureACmotorsteplessspeedregulatingtechnology,itsuniqueexcellentcontrolperformanceiswidelyappliedtothespeedcontrolfield,especiallyinwatersupplyindustry.Duetothesafetyinproductionandthewaterqualityofspecialneeds,forconstantpressurewatersupplywiththestringentrequirements,sothefrequencycontroltechnologyhasbeenmorein-depthapplication.Constantpressurewatersupplywaystoadvancedtechnology,constantpressure,convenientoperation,reliableoperation,energysaving,highdegreeofautomation,inpumpstationwatersupplycanperformthefollowingfunctions:(1)tomaintainconstantpressure;(2)thecontrolsystemcanbemanualorautomaticoperation;(3)apluralityofpumpautomaticswitchoperation;(4)systemofsleepandwake,whenpeoplestopwhenwater,thesystemisinasleepstate,untilthewaterdemandautomaticallywake;(5)adjuststhePIDparametersonline;(6)pumpunitandcircuitprotectiondetectionalarm,signaldisplay.Theactualpressureofthepipenetworkfeedbackandagivenpressurewerecompared,whenthepressureofapipenetworkislow,increasetheoutputoffrequencyconverter,pumpspeedfaster,watersupplyquantityincreases,forcingthepipenetworkpressurerise.Vicepumpspeedslowdown,reducethewatersupplypipenetworkpressuredrop,,tokeeptheconstantpressurewatersupply.SystemhardwarestructureSystemusesapressuresensor,PLCandinverterasacentralcontroldevice,toachieveadesiredfunction.Source:networktransmissionanddistributionequipmentinstallationinpipelinepressuresensor,fordetectingthewaterpressureofthepipenetwork,convertingpressureis4~20mAcurrentorvoltagesignalis0~10V,suppliedtotheinverter.Converterpumpmotorcontroldevice,inaccordancewiththeconstantwaterpressureneedstobe0~50Hzfrequencysignalsupplypumpmotor,adjustitsspeedSAJconverterispowerful,i.e.pre-programmedsetparameterset,willusetherequiredintheprocessofsettingthenumberofparametersisreducedtoaminimum,defaultvalueaccordingtotheapplicationparameterofthemacrochoiceanddifferent.燕京理工学院机电工程学院——外文文献原稿和译文ThesystemadoptsthePIDcontrolapplicationmacro,closedloopcontrol.Inverterbasedonaconstantpressurecorrespondingtothevoltagesettingvalueandfromthepressuresensortoobtainthefeedbackcurrentsignal,theuseofPIDcontrolmacroautomaticallyadjust,changethefrequencyoutputvaluetoadjustthecontrolthespeedofthepumpmotor,toensurethatthepipenetworkpressureconstantrequirements.Theapplicationofinverterintheconstantpressurewatersupply1.ThecharacteristicandanalysisofvariablefrequencyspeedregulationThewaterusersingeneralisdynamic,sothewatersupplyisinsufficientorexcesswatersupplysituationhasoccurred.Thewatersupplyandtheimbalancebetweentheconcentratedreflectioninwatersupplypressure,namelywaterandwatersupplyisless,thelowpressure;lesswaterconsumptionandwatersupply,thepressure.Keepthewaterpressureconstant,canmakethewatersupplyandwaterbalancebetweenwatersupplyandwaterforalongtime,thatis,lesswate...