PROCEDURE FOR SCALING UP THE OPERATIONAL AVAILABILITY OF A COMPRESSOR

Description

2 compromiseonperformance.However,likemostmechanicalmachines, someformofdegradationwillinevitablyoccurovertimedueto, amongotherthings,thepresenceofrotatingparts,contamination intheambientairaroundthemachine,largetemperature differences,thelossofoilandotherinternalorexternal5 influencesthatmaypreventand / ordeterioratetheproper functioningofthecompressor.Traditionalmaintenancepractices oftenfallshortduetotechnicalandeconomicconstraints, resultinginunintendedcompressordowntime.Thereisaneedfor amethodthatcanproactivelyincreasecompressoravailabilityby10 managingitsoperationalparametersmoreeffectively.

[04] Traditionally,aircompressormaintenanceisperformedona fixedschedule,whichcanresultinunnecessarydowntimeandwasted resources.Withsmarttechnologies,maintenancecanbeperformed15 basedonthecompressor'sactualcondition.

[05] Predictivemaintenancecansavetimeandmoneybyreducing theneedforfrequentmaintenancechecks.Itcanalsoprevent unexpectedequipmentfailures,whichcanleadtocostlyrepairs20 anddowntime.Furthermore,predictivemaintenancecanincreasethe lifespanoftheaircompressor,reducingtheneedforreplacements andloweringcosts.

[06] Asolutiontoavoidanunintentionalandprematurefailureis25 toscheduletechnicalmaintenanceinatimelyandregularmanner. Thisiscommonlyknownaspreventivemaintenance.Necessary actionscanthenbetaken,suchaslubricationofmechanicalparts, replacementofoilintherefrigerantcoolingcircuit,and BE2025 / 5066 3 replacementofcriticalparts.However,asisknownbythe professional,suchpreventivemaintenanceisnotalwaysdoneina timelymannerduetoavarietyofbothtechnicalandeconomic reasons,suchaslackofsparepartsorstaffshortages.The compressorwillthenbekeptinoperation,whetherintentionally5 ornot,eventhoughthereisariskofsuchfailure.

[07] Configuringeveryinstallationinthemostefficientwayis notastraightforwardtask.Thereisalargevarietyofthese systemsthatmakeimprovingtheoptimizationofthesystems10 difficultforhumans.Multiplecompressorsmaybeconnectedina compressedairsystemtosupplycompressedairtothesame distributionnetwork.Thesecompressorscouldbeofseveraltypes, sizes,andages,whichcouldcauseanunequalloadandsystem inefficiencies.Thereisalargevarietyofpneumaticnetworks15 thatcanbedividedintovariouscategoriesaccordingtotheir structure,size,layout,andcapacity.Customersmayhaveseveral requirementsforthesystemintermsofenergyefficiencyand demandrequirements. 20

[08] Tohandlethelargevarietyofsystemsinwhichacompressor canbeconfigured,thereisapluralityofparametersavailable.

[09] Theseparametersmaybetechnical,suchaspower,pressure ratioand / orstart-uptime.Otherparametersmayincludeeconomic25 parameters,suchasinvestmentand / ormaintenancecosts,oreven environmentalrequirements,suchasenergy-efficiencyand / ornoise levelsduringoperation.Takingalltheseparametersintoaccount BE2025 / 5066 4 andcorrectingforthedifferentsystemlayoutsisdifficultin practice.

[10] Inthepresentinvention,amethodfordeterminingand controllingtheoperatingmarginofacompressorsystemis5 described.Themethodcomprisesiterativelyperformingthe followingsteps:measuringoneormoreprocessquantities indicativeoftheinstantaneousoperationofthecompressor; estimatingasetofprocessquantitiesbasedonmeasuredprocess quantitiesand / orontheinternalsetpointsand / ortheexternal10 setpointsofthecompressorusingamodelthatcomprisesaheat transfercharacteristicbetweenthecompressoranditscooling circuit,wheretheheattransfercharacteristicincorporatesa degradationparameter;matchingtheestimatedprocessquantities tothemeasuredprocessquantitiesbyadjustingthedegradation15 parameter;determiningtheoperatingmarginbasedonthe degradationparameterandtheinternalsetpointsofthe compressor;andexecutingtherelatedtaskifthedegradation parameterexceedsapredefinedsoftorhardlimit,thereby restrictingtheoperatingrangetoensuresafeoperationwhen20 required.

[11] Thestepofmeasuringisunderstoodtoberetrievingthe value(s)ofaquantityobtainedfromoneormoreobservations, recordings,orsamplingsataspecificphysicallocationbymeans25 ofsuitableinstruments,suchassensorsforexpressinganobserved quantityinanumberwitharelevantunitthatcanbecompared withothervaluesofthesamequantity. BE2025 / 5066 5

[12] Thestepofestimatingisunderstoodtobethedetermination ofavalueofaquantitybasedonmeasuredprocessquantities and / orsetpoints,usingascientificmodelrepresentativeofa technicalprocessand / orapparatuswithasinputthemeasured processquantitiesand / orsetpoints,andasoutputthevaluethat5 needstobedeterminedandisthereforeestimated,basedononeor morecalculations.

[13] Thestepofmatchingisunderstoodtohaveasetofparameters withinasetofequationsiterativelyconvergetoasetofcertain10 optimalvalues,suchthatthedifferencebetweenthemodelandthe measurementsisminimal.Thestepofmatchingisthereforedone basedononeormorecalculations.Also,iterativelyperforming thestepsmeansthatthestepsareperformedrepeatedly. 15

[14] Inafirststep,processquantitiesaremeasuredthatare indicativeoftheinstantaneousoperationofthecompressor system.Inanembodimentoftheinvention,theseprocessquantities areanambienttemperature,coolingtemperature,compressor temperature,electricalcurrent,speed,inletpressure,outlet20 pressure,ambientpressure,humidity,and / orflowrate. Furthermore,notethatthislistisnon-exhaustiveandthatother processparameters,representativeofthecompressoroperation, canalsobemeasured.Ontheotherhand,itshouldalsobenoted thatnotallprocessquantitiesaremeasured,butsomeofthem.25

[15] Inthepresentinvention,theprocessquantitiesarevariables orfactorsthatcanbemeasured,someofwhichcanalsobe controlledtoinfluencetheoperationandperformanceofthe compressorsystem.Thesevariablesarecriticalformaintaining30 BE2025 / 5066 6 optimalfunction,andensuringsafetyofthesystem.Theyinclude bothexternalsetpoints,whicharedirectlyrelatedtothe applicationrequirements,andinternalsetpoints,whichare relatedtothecompressor’sinternaloperationsandsafetylimits. Externalandinternalsetpointsaredefinedrelativetowhatis5 consideredinternalorexternalfromtheperspectiveofthemaster controllerofthecompressororcompressorsystem.

[16] Inasecondstep,theseoneormoreprocessquantitiesofthe compressorareestimated.Thisestimationismadebasedononeor10 moremeasuredprocessquantitiesand / orsetpointsofthe compressorthatserveasinputtoascientificmodelofthe compressor,whereintheoutputofthemodelaretheestimated processquantities. 15

[17] Itshouldfurtherbenotedthatthefirstandsecondsteps canbeperformedinparallelandsimultaneously.Theusedterm 'first'and'second'thereforeservestodistinguishbetweenthe differentstepsbutdoesnotindicateaspecificchronologyand / or hierarchybetweenthetwosteps.Ontheotherhand,itmust,of20 course,beunderstoodthatestimatingprocessquantitiesbasedon othermeasuredprocessquantitiesdoesimplythatthismeasurement iscarriedoutpriortotheestimate.

[18] Themodelrepresentativeofthemachineisascientificmodel25 suchasaphysicalormulti-physicalmodelcomprisingasetof differentialequationsand / orempiricalrelationsdescribingthe differentphysicalpartsofthemachineandtheirdependenceon eachotherbymeansofoneormorecommonvariables. BE2025 / 5066 7

[19] Inanembodimentofthepresentinvention,oneormoreprocess quantitiesareestimatedbasedonamodelcomprisingaheat transfercharacteristicbetweenthecompressorandthecooling circuit,whereinthisheattransfercharacteristiccomprisesa5 degradationparameter.

[20] Furtherinthepresentinvention,amethodfordynamically adjustinginternalsetpointstoensurecontinuedsafeand efficientperformanceinthefaceofcomponentdegradationis10 introduced.

[21] Thepresentinventioncomprisesasetpointshiftingprocess thatadjustsinternalsetpointsdynamicallybasedonreal-time conditionsandthedetermineddegradationparameter(s).By15 shiftinginternalsetpointslikefanspeed,andoilinjection pressure,thesystemcantemporarilyadapttochangingoperational demandsunderdegradingconditionswithoutcompromisingsafety.

[22] Thesystemcontinuouslymonitorsthehealthofthecompressor20 usingsensordataandacompressormodel.Thehealthscorereflects thecondition,degradation,andageingofthecompressororits components.

[23] Byquantifyingdegradationanditsimpactonperformance,the25 systemcanproactivelymanageandmitigatetheeffectsofwearand contamination.Thisallowsfortimelyinterventionsbefore criticalfailuresoccur. BE2025 / 5066 8

[24] Thesystemadaptsinternalsetpointsbasedonreal-time conditions,suchasambienttemperature,loaddemandsand degradationparameters.Forexample,itadjuststhefanspeedto preventoverheatingwhenthecoolingcircuitispartiallyclogged.5

[25] Thepresentinventiontakesintoaccountmulti-dimensional ambientconditions(temperature,humidity,inletpressure)and adjustsoperationaccordingly,optimizingperformanceunder variousenvironmentalfactors.10

[26] Whenexternalsetpointscannotbereachedwithoutrisking safety,thesystemtemporarilyshiftsinternalsetpointsto maintainsafeoperationandtoallowtoreachtherequiredexternal setpoints.Thismayinvolvethefanmotorrunningathigherspeeds,15 whichcanincreaseitstemperatureandageingrate,butkeepsthe compressoroperatingsafely.

[27] Thesystemraiseswarningswhensetpointshiftingisapplied, informingoperatorsaboutthepotentiallyincreasedriskof20 componentageing.Thisensuresthatanytrade-offsaremade consciouslyandmanagedappropriately.

[28] Bycontinuouslymonitoringthehealthanddegradationof components,thesystemenablespredictivemaintenance.Maintenance25 actionsarescheduledbasedontheactualconditionofthe compressor,reducingunnecessarydowntimeandextendingcomponent life.BE2025 / 5066 9

[29] Thesystem'sabilitytoadapttodegradationandcontamination levelsallowsformoreoptimalandcost-efficientschedulingof overhauls,ensuringtheyareperformedonlywhennecessary,and avoidingprematureinterventions.5

[30] Thesystemensuresthatthecompressoroperateswithinsafe limitsatalltimesbydynamicallyadjustinginternalsetpoints andoperatingrangesbasedonreal-timehealthscoresand environmentalconditions.10

[31] Incaseofsignificantdegradationorfailuretoreach externalsetpoints,thesystemimplementsfallbackmechanismsto maintainsafeoperation,forinstance,bytemporarilyincreasing coolingefforts.15

[32] Traditionalcompressorsystemsoperatewithfixedand / ora predeterminedrangeofinternalsetpointsandapredetermined externalsetpointrange.Inotherwords,thesetpointsare maintainedregardlessofthecompressor’shealthcondition.20

[33] Regularmaintenanceschedulesareestablishedtoinspectand cleancomponents,replacewornparts,andensurethecompressor operateswithinsafelimits.Preventivemaintenancecanbe effectivebutoftenleadstounnecessarydowntimeandcosts.25

[34] Advancedcompressorsareequippedwithsensorstomonitor variousparameterssuchastemperature,pressure,humidityand BE2025 / 5066 10 vibration.Datafromthesesensorsareusedtoassessthehealth ofthecompressorandidentifypotentialissuesbeforetheylead tofailures.

[35] Somecompressorsystemsincluderedundantcomponents,suchas5 additionalcoolingfansorbackupcompressors,toensurecontinued operationifaprimarycomponentfailsorbecomesinefficient.

[36] Incaseofcomponentfailureordegradation,thesystemcan automaticallyswitchtobackupcomponentstomaintainoperation.10 Thisapproachincreasessystemreliabilitybutalsoadds complexityandcost.

[37] Theattemptsmadeinthestateofthearttoalleviatethe problemsassociatedwithoptimizedperformanceofacompressedair15 systemaredescribedinthefollowingpatents.

[38] UnitedStatesAppl.No.US2021172436disclosesacompressor orpump,includingatleastonecompressororpumpelementfor pressurizedsupplyofafluidtoanetworkofconsumersofsuch20 pressurizedfluid;amotorcoupledwiththecompressororpump element.Thecompressororpumpisequippedwithacontrolhaving abasiccontrolforthenominalregulationofoneormorecontrol parameters(Q,pw)asafunctionofadesired,setworkingpoint ofthecompressorwithinthenominalsetworkingrangeofthe25 compressororpump,setduringdesign.Thecontrolisfurther providedwithanadditionalcontrolfunctionforstaticordynamic adjustmentoftheworkingrangelimitvalues.Thenominalcontrol rangeofoneormorecontrolparametersisadjustedasafunction oftheactualworkingconditionsofthecompressororpumpthat30 deviatefromthenominalworkingconditions.BE2025 / 5066 11

[39] US2005165581disclosesamethodforprotectinganelectric motorofamotordrivenconsumerequippedwithacontrollerfor controllingthecapacityorthepoweroftheconsumer,comprises thefollowingsteps:thedeterminationofthethermalconditionof5 themotorbydirectmeasurementonthemotor;andthelimitation ofthemaximumcapacityorthemaximumpoweroftheconsumerasa functionoftheaforementioneddeterminedthermalcondition.

[40] US2017130982relatestomethods,devices,andsystemsforan10 inferentialsensorforinternalheatexchanger.Onedevice includesamemory,andaprocessorconfiguredtoexecuteexecutable instructionsstoredinthememorytoreceiveanumberofmeasured processquantitiesofaheatexchanger,includinganumberof measuredinletprocessquantitiesandanumberofmeasuredoutlet15 processquantities,predict,usingadynamicdifferentialmodel includingthenumberofmeasuredinletprocessquantities, internalparametersoftheheatexchangerandanumberofoutlet processquantitiesoftheheatexchanger,comparethenumberof measuredoutletprocessquantitieswiththenumberofpredicted20 outletprocessquantities,andupdate,basedonthecomparison, theinternalparametersoftheheatexchanger.

[41] Thestate-of-the-artmethodsprovidearangeofsolutionsto managecompressordegradationandcoolingcircuitcontamination.25 However,thereisaneedformoreadaptive,real-timeapproaches thatcandynamicallyadjustoperatingparametersbasedonthe actualconditionofthecompressor,ensuringsafeandefficient operationwithoutexcessivemaintenanceordowntime.Theproposed inventionaddressesthesegapsbyintroducingacomprehensive30 BE2025 / 5066 12 systemthatcontinuouslymonitorsandadjustsinternalsetpoints tooptimizecompressorperformanceundervaryingconditions.

[42] Thepresentinventionmaximizesefficiencybydynamically adjustinginternalsetpointsandoperatingranges,thecompressor5 systemoperatesmoreefficientlyundervaryingdegrading conditions,reducingenergyconsumptionandimprovingoverall performanceinthelongterm.

[43] Predictiveandcondition-basedmaintenancereducesthe10 frequencyandcostofmaintenanceactivities,whileoptimized overhaulintervalsensuretimelyandeffectiveinterventions.

[44] Thesystemtemporarilymaintainssafeandreliableoperation evenunderdegradedconditions,preventingunexpectedfailuresand15 ensuringcontinuousservicetothecustomer.

[45] Byintegratingtheseinnovativemechanisms,thepresent inventionoffersacomprehensivesolutionthatmaintainsand / or maximizessystemefficiencyevenunderdegradingconditions,20 prolongstheoperationofthemachine,continuessatisfyingthe flowdemandevenwithacompressorthathasdegradedcomponents andsubsystems,andprovidesreliableperformanceinawiderange ofoperatingconditions. 25

[46] Traditionalcompressorsystemsoperatewithinfixedsetpoint rangesthataredeterminedatthetimeofmanufacture.Overtime, componentsdegrade,andthecoolingcircuitcanbecome contaminated,leadingtoinefficientoperationandpotential BE2025 / 5066 13 overheating.Thepresentinventionaddressestheseissuesby dynamicallyadjustinginternalsetpointsbasedonreal-time measurementsandmodelpredictions. 5 ObjectsofthePresentInvention

[47] Oneoftheobjectivesofthisinventionistoprovideaway tomanageacompressorsystemoptimallyandefficiently.10

[48] Theobjectofthepresentinventionistoadjusttheinternal setpointsdynamicallybasedonreal-timeoperationalconditions, ensuringthecompressorrunsatoptimalefficiency. 15

[49] Anotherobjectofthepresentinventionistohandle situationswherethecompressor'scoolingcircuitisdegradedor contaminated,ensuringthatthecompressorcanstilloperate safelybydynamicallyadjustingfanspeedandotherinternal setpoints.Tointegratereal-timedataandcompressormodelsto20 predictandrespondtooperationalchallengesproactively, enhancingsystemresilienceandreducingtheriskofshutdowns.

[50] Anotherobjectofthepresentinventionistoreducetheamount oftimeatechnicianneedstooptimizemaintenanceplanningand25 deliveryforanentirefleetofcompressorsystems. BE2025 / 5066 14

[51] Anotherobjectofthepresentinventionistoadaptthe compressor'sinternalsetpointsbasedonchangingenvironmental andloadconditionstomaintainefficientperformance.

[52] Anotherobjectofthepresentinventioniscontinuously5 monitoringthehealthofthecompressoranditscomponents, providingareal-timehealthscorethatreflectstheircondition anddegradation.

[53] Anotherobjectofthepresentinventionisimplementinga10 mechanismthatlimitsoperatingrangeswhendegradationreaches levelsthatthreatensafeoperation,ensuringthecompressorcan continuetooperatewithinsafelimits.Also,providingwarnings wheninternalsetpointshiftingisapplied,ensuringthat operatorsareinformedofpotentialsafetyconcerns.15

[54] Anotherobjectofthepresentinventionistoenable predictivemaintenanceschedulingbasedontheactualcondition andhealthofthecompressor,reducingunnecessarymaintenance activitiesanddowntime,determiningtheoptimalintervalsfor20 overhaulsbasedondegradationdataandhealthscores,ensuring maintenanceactionsaretimelyandnecessary.

[55] Anotherobjectofthepresentinventionistoensurethat externalsetpoints,inanembodimentoftheinvention;motorspeed25 andoutletpressure,aremaintainedunderallcircumstancesto preventoperationaldisruptionsforthecustomer'sapplications. Toimplementfallbackmechanismsthatmaintainsafeoperationeven whenexternalsetpointscannotbereached,safeguardingthe customer'sapplications,andensuringcontinuousservice.30 BE2025 / 5066 15

[56] Anotherobjectofthepresentinventionistoadapttovarious ambientconditions(temperature,humidity,inletpressure)and multi-dimensionaloperatingranges(speed,outletpressure)to optimizeperformanceacrossawiderangeofenvironments.Toallow5 fortemporaryadjustmentsinthedesignrangeofcomponents,such asincreasingfanspeed,tocompensatefordegradedconditionsand maintaincompressorperformance.

[57] Byachievingtheseobjects,thepresentinventionprovidesa10 robustandintelligentsystemthatnotonlyoptimizesthe efficiencyandlifespanofcompressorsystemsbutalsoenhances theirsafety,reliability,andadaptabilitytovaryingoperational conditions. 15 SummaryofthePresentInvention

[58] Thepresentinventionshowsanadvancedcontrolsystemfor20 compressorsthatdynamicallyoptimizesefficiency,prolongsthe timeuntilthenextoverhaul,andensuresreliableperformance. Centraltothisinnovationaretwokeycomponents:thesetpoint shiftingblockandthelimitingsetpointrangesblock. 25

[59] Thepresentinventionrelatestoacomprehensivehealth scoringsystemthatmonitorstheconditionandagingofthe compressoranditscomponents.Thissystemguidesmaintenanceand operationaladjustmentsbyprovidingadegradationassessmentand BE2025 / 5066 16 issuingwarningswhennecessary.Theadaptivecontrolfeature modifiesoperationalparametersbasedonreal-timedata,ensuring optimalperformanceandpredictivemaintenance.

[60] Asusedherein,theterms'compressorspeed'and'motorspeed'5 maybeusedinterchangeably,unlessotherwisespecified.Inmany implementations,thecompressorisdirectlycoupledtothemotor, resultinginthesamerotationalspeedforboth.However,incases whereatransmissionmechanismsuchasagearbox,beltdrive,or variable-speeddriveisemployed,thecompressorspeedmaydiffer10 fromthemotorspeed.Eveninsuchcases,thereisadirect proportionalrelationshipbetweenthemotorspeedandthe compressorspeed.Unlessthedistinctionisrelevanttothe context,referencestoeithertermshouldbeunderstoodto encompassbothpossibilities.15 FiguresofthePresentInvention 20

[61] Accompanyingdrawingsaregivensolelyforthepurposeof exemplifyingamethodforscalingupcompressoroperational availability,whoseadvantagesoverpriorartwereoutlinedabove andwillbeexplainedinbriefhereinafter.25

[62] Thedrawingsarenotmeanttodelimitthescopeofprotection asidentifiedintheclaimsnorshouldtheybereferredtoalone inanefforttointerpretthescopeidentifiedinsaidclaims BE2025 / 5066 17 withoutrecoursetothetechnicaldisclosureinthedescriptionof thepresentinvention.

[63] Figure1isablockdiagramdisplayingfunctionalblocksofa compressorsystemaccordingtothepresentinvention.5

[64] Figure2isagraphplottingcompressorspeedontheX-axis andambienttemperatureontheY-axis.Thegraphillustratesthe operationallimitsofthesystemundernormalconditionsandina degradedstateaccordingtothepresentinvention.10

[65] Figure3expandsontheinformationpresentedinFigure2by addingathirdaxisrepresentingoutletpressureaccordingtothe presentinvention. 15

[66] Figure4isachartplottingmotorspeedontheX-axisand temperatureontheY-axisincludingseverallinesrepresenting differentconditionsoftheoilaccordingtoanembodimentofthe invention.20

[67] Figure5showstheeffectofcoolercloggingonthe relationshipbetweenfanspeedandmotorspeed,illustratinghow thesystemdynamicallyadjustsoperatinglimitsandinternal setpointstomaintainsafeoperationascloggingprogressesfrom 60%to80%accordingtoanembodimentoftheinvention.25 BE2025 / 5066 18 DetailedDescriptionofthePresentInvention

[68] Fig.1illustratesablockdiagramofacontrolsystemdesigned todynamicallyoptimizetheoperationofacompressorbyadjusting internalsetpointsand / orlimitingoperatingrangesbasedonreal-5 timehealthassessments.Acontroller,whichmanagestheoverall operationofthecompressor.Saidcontrolleracceptsexternal setpointsfromtheuser,operatororexternalsystemsandsets valuesforinternalsetpoints,bothofwhicharechosentouphold thecustomersairconsumptionrequirementsinthebestpossible10 way.Theseexternalsetpointsarecrucialformaintainingthe operationalpressureofthenetwork,andpotentiallytheairflow tothenetwork-orcoolingwateroutflowdeliveredbythe compressorsystemandensuringthecustomer'sapplicationsrun smoothly.Inanembodimentoftheinvention,saidcontroller15 controlstheoutletpressuretomeettheexternalsetpointbased onaPIDregulation.Thefigure1illustratesacomprehensive controlsystemwhereeachcomponentinteractstodynamically manageandoptimizetheoperationofthecompressor.The integrationofreal-timehealthassessments,setpointadjustments,20 andoperatingrangelimitationsensuresefficientandsafe operation,adaptingtovaryingconditions.

[69] Inthepresentinvention,thesetpointshiftingblockis essentialtodynamicallyadjustinternalsetpointstooptimize25 compressorperformancewhileensuringsafety.Internalsetpoints includeparametersthatcanbevariedwithincertainlimits,such asfanspeed,andoilinjectionpressure.Theseparametersnormally operatewithinstandarddesignlimits,asdeterminedbythe internalsetpointgeneratorblock,butcantemporarilybeadjusted30 BE2025 / 5066 19 tomaintainsystemperformancewithoutriskingimmediate additionaldegradationorwear.Thesetpointshiftingblock receivesinputfromtheinternalsetpointgeneratorandsuggests newsetpointsbasedoncurrentoperatingconditionsandhealth scores.Theseadjustedsetpointsarethenusedbythecontroller5 tocontrolthecompressor.

[70] Internalsetpointsaretheparameterswithinacompressor systemthatthesetpointshiftingblockadjustsautonomouslyto fine-tuneandoptimizethesystem'sperformance.Thesesetpoints10 aredeterminedbasedonthesystem'sinternallogic,real-time sensordata,andtheoveralloperationalstateoftheequipment. Theyserveasintermediarytargetsthatthecontrolsystemusesto ensuresmoothandefficientoperation,withoutrequiringdirect inputfromtheoperatororexternalentities.15

[71] Internalsetpointscanbechangedfrequentlybythecontrol algorithmtoadapttovaryingoperationalconditions,suchas changesintemperatureorpressure.Thecontrolunitmonitorsthese conditionsandmodifiesinternalsetpointsinreal-time.20

[72] Internalsetpointsoftenplayaroleinfine-tuningthe performanceofspecificcomponentsorsubsystemstomeetthelarger goalsdefinedbyexternalsetpoints.Examplesofinternal setpointsare:fanspeed,motororinternalcoolingratesthatcan25 beadjustedtomanagethermalconditionswithinthecompressor, valvepositions,etc.

[73] Inastandalonecompressorunit,thecompressorspeedmight beconsideredaninternalsetpointbecauseitiscontrolledbythe30 BE2025 / 5066 20 controlalgorithmtoregulatetheoutletpressure,whichisoften theprimaryperformancecriterionspecifiedbythecustomer.The compressorspeedmaybeadaptedtobalancetheflowdemandbythe customerwithflowsupplyfromthecompressoratthepressure desiredbythecustomer.Inthiscontext,thesetpointshifting5 blockadjustsinternalsetpointstomaintainthedesiredoutlet pressureasaccuratelyaspossible.Inasystemwithmultiple compressorsoperatinginparallel,thespeedofeachindividual compressorcanbetreatedalternativelyasanexternalsetpoint. 10

[74] Externalsetpointsrepresenttheparametersthataredefined andsetbytheuser,operator,orexternalsystems.Thesesetpoints specifytheoverallperformancetargetsordesiredoutcomesfor thecompressorsystem.Thecontrolunit'smaingoalistoachieve andmaintaintheseexternalsetpointsbyadjustingtheinternal15 setpointsaccordingly.

[75] Externalsetpointsaretypicallyestablishedbythecustomer oroperatorandarebasedonthespecificrequirementsforthe application.Theyreflectthedesiredperformancemetricssuchas20 thetargetpressure,allowedvariationofthetargetpressure, temperature,orairflowrate.

[76] Thesesetpointsaregenerallylessflexiblethaninternal setpointsbecausetheyrepresentfixedperformancetargetsthat25 thesystemmustmeettosatisfytheoperationalrequirements.The controlunitstrivestoachievethesetargetswhilemanagingthe internalsetpointstodealwithvariationsinsystemconditions. BE2025 / 5066 21

[77] Acommonexampleofanexternalsetpointinindustrial applicationsisthespecifiedairpressurerequiredbypneumatic toolsorothermachinery.Thecompressorsystemadjustsits internaloperationstoconsistentlymaintainthespecified pressure,ensuringthatdownstreamprocessesfunctionsmoothly.5

[78] Thedistinctionbetweeninternalandexternalsetpointsis notalwaysfixedandcanvarydependingonthespecific configurationofthecompressorsystem.Thecontextinwhichthe systemoperatesdetermineswhichparametersaretreatedas10 internalorexternal.

[79] Inasystemwithoneormultiplecompressorsoperatingin parallelorinserieswherestandalonecompressorsarecontrolled bytheircontrollers,individualcompressorspeeds,inter-stage15 pressures,andcoolingratesareusuallyconsideredinternal setpointsbecausethesetpointshiftingblockmanipulatestheseto balancetheloadandmaintainsystemefficiency.Thecompressor outletpressuresorairflowresultinginoverallsystemoutput pressureortotalairflowdeliveredtotheenduserwouldbe20 consideredexternalsetpoints,asthesearedictatedbythe customer’srequirements.

[80] Inasystemwithmultiplecompressorsoperatinginparallel orinserieswhereindividualcompressorsarecontrolledbya25 centralcontroller,individualcompressorspeeds,internalfan speeds,outletpressures,orcompressorbypassvalvepositions mightbeconsideredinternalwithrespecttothelocalandcentral controllerofthemultiplecompressors.Theyareadjustedbythe centralcontrollerorlocalcontrollerstooptimizeperformanceof30 BE2025 / 5066 22 themultiplecompressorsoperatinginparallelorinseriesand protectthemultiplecompressorsfromwear.Theoverallsystem outputpressureortotalairflowdeliveredtotheenduserwould beconsideredexternalsetpoints,asthesearedictatedbythe customer’srequirements.5

[81] Whenthecompressorsystemoperates,theexternalsetpoints aretriedtobemetbyshiftinginternalsetpoints.Ifthesystem detectsdegradationorariskofoperatingoutsidesafeconditions, itdynamicallyadjustsinternalsetpointstokeepthesystemstable10 whilestrivingtoachievetheexternaltargets.However,ifthe internaladjustmentsarenotsufficienttomeettheexternal setpointsinasafeway,thecontrolunitmayissuealertsor warnings,andasalastresort,modifytheexternalsetpoints. 15

[82] Ahealthscoringsystemanalyzesthesensordatain conjunctionwithacompressormodeltoassessthecurrenthealth andconditionofthecompressoranditscomponents.Thisscore reflectsthecurrentstateofthecompressor,indicatinglevelsof degradationandpotentialrisks.Thehealthscoringsysteminforms20 thesetpointshiftingandlimitingsetpointrangesblocks, allowingforreal-timeadjustmentstomaintainoptimalperformance andsafety.

[83] Thehealthscoringsystemalsofacilitatespredictive25 maintenance.Byassessingtheconditionofthecompressorandits components,thesystemcanpredictwhenmaintenancewillbe required,allowingfortimelyinterventionsthatprevent unexpectedbreakdownsandextendthelifeofthecompressor. 30 BE2025 / 5066 23

[84] Thecompressormodel,amathematicalrepresentationofthe compressor,predictsitsbehaviorundervariousoperating conditionsandaidsingeneratingaccuratehealthscoresby simulatingdifferentscenariosbasedoncurrentsensordata.The systememploysanetworkofsensorstocollectreal-timedataon5 variousoperationalparameters,includingtemperature,pressure, speed,andmore.Thisdataisfedintothecompressormodel,which simulatesthecompressor’sbehaviorandpredictsfuture conditions,includingpotentiallyharmfuloperatingconditions giventhegeneratedhealthscore.Basedonthesepredictionsand10 currenthealthscores,wheneverpotentiallyharmfuloperating conditionsmayarise,thesystemdynamicallyadjustsinternal setpointsandoperatingranges.

[85] Thelimitingsetpointrangesblockadjustsitselfaccording15 totheallowableoperatingrangesofthecompressorbasedonthe healthscore.Whendegradationreachesacertainlevel,the operatingrangeisreducedtoensuresafeoperation.Inputstothe limitingsetpointrangesblockincludecomponent-specific degradationinformation.Degradationovertime,representedas20 degradation(t),ismonitoredforspecificcomponents,guidingthe adjustmentsmadebythelimitingsetpointrangesblock.

[86] Thefirstactiontakenbythelimitingsetpointrangesblock whendegradationisdetectedistodecideanewrangeofallowed25 internalsetpoints.Theinternalsetpointgeneratorcreatesnew internalsetpointswithintherangeofinternalsetpoints.Then, thesetpointshiftingblockimplementsinternalsetpointshifting. Thisprocessinvolvesdynamicallyadjustingtheinternalsetpoints ofthecompressor,suchastemperaturethresholdsorfanspeeds,30 tocompensatefortheidentifieddegradation.Thesetpoint BE2025 / 5066 24 shiftingblockutilizesreal-timedataandthehealthscoreto maketheseadjustments.Internalsetpointshiftingisprioritized overexternalsetpointshiftingasitallowsthesystemtomeet theexternalsetpointsbytemporarilysteppingoutsidethe originaldesignconstraintsofsomeinternalsetpoints,5 guaranteeinguptimeofthesystem.

[87] However,ifinternalpointshiftingaloneisinsufficientto maintainsafeandefficientoperation,thesystemthenconsiders adjustingexternalsetpointsasalaterstep.Externalsetpoint10 shiftinginvolvesmodifyingthebroaderoperationalparameters, suchaspressuresettingsorflowrates,tofurtherreducestrain onthecompressorcomponents.Thisstepistakenwhenthe degradationistoosignificantforinternaladjustmentsaloneto mitigatetherisks,ensuringthatthecompressorcontinuesto15 operateevenunderdeterioratingconditions.Bysequentially applyingthesestrategies—startingwithinternaladjustmentsand escalatingtoexternalmodificationsonlywhennecessary—the systemmaximizesefficiency,prolongsthetimeuntilthenext overhaul,andensuresreliableperformance.20

[88] Thesetpointsarecontinuouslymonitoredandadjustedbythe setpointshiftingblockandthelimitingsetpointrangesblock.By dynamicallycontrollinginternalsetpoints,thesystemcan maintainoptimalperformanceevenascomponentsdegradeovertime.25 Adjustmentsofinternalsetpointshelptopreventunsafeoperating conditions,ensurethatexternalsetpointsaremet,andmanagethe agingofinternalcomponents.Forinstance,increasingthefan speedmayhelpcooldownthecompressorbelowthesafetythreshold whenitcontainsadegradingcomponentandthereisahighambient30 temperature,albeitatthecostoffasterfanmotoraging. BE2025 / 5066 25

[89] Inanembodimentoftheinvention,awarningsystemmonitors iftheexternalsetpointscannotbereacheddespiteofadjusted internalsetpoints.Iftheexternalsetpointisnotachieved,it triggersawarning,indicatingapotentialriskofaccelerated5 agingforcertaincomponentsandofthecustomerrequirementnot beingmetunderallpossiblecircumstances.Thisriskis communicatedtothecontrollerandrelevantblockstoensurethat temporarymeasuresdonotcauselong-termdamage.Inanembodiment oftheinvention,theusercoulddecidetostartaback-up10 compressorasaresultofsaidcommunication.

[90] Additionallyinanotherembodimentoftheinvention,the warningsystemisdesignedtonotifytheuser,operatororexternal systemwheneverinternalsetpointshiftingoccurs.Ifthesystem15 initiatesinternaladjustmentstocompensatefordegradationor otheroperationalconcerns,thewarningsystemtracksthese changesandevaluatesthepotentialimpactonthecompressor's components.Specifically,itassessestheriskofaccelerated agingforlesscriticalcomponents,whichmayexperienceincreased20 strainduetotheshiftedsetpoints.Thewarningsystemthen generatesanalertthatdetailsthespecificinternaladjustments madeandhighlightstheassociatedrisks,particularlythe potentialforacceleratedwearonnon-essentialcomponents.25

[91] Thiswarningservesasacrucialfeedbackmechanism,allowing theusertomakeinformeddecisionsaboutfurtheradjustmentsor maintenanceactions.Byprovidingreal-timeinformationaboutthe consequencesofinternalsetpointshifts,thesystemensuresthat temporarymeasuresdonotinadvertentlyleadtolong-termdamage.30 BE2025 / 5066 26 Theintegratedapproachofmonitoringbothinternalandexternal adjustments,combinedwitharobustwarningsystem,ensuresthat thecompressoroperateswithinsafelimitswhilebalancing performanceandcomponenthealth. 5

[92] Accordingtotheinvention,aneffectivesetpointdomain representstheactualrangeofsetpointswithinwhichthe compressorcansafelyoperate.Thisdomainisdynamic,changing basedonreal-timeconditionsandhealthassessments. 10

[93] Figure2isatwo-dimensionalplotwithambienttemperature onthey-axisandcompressorspeedonthex-axis.Itillustrates theoperationalrangelimitsofthecompressorunderbothnormal anddegradedconditions.Thesolidrectangledefinesthenormal operatingrangewherethecompressorcanfunctionwithoutany15 issues.However,asthecompressordegradesduetofactorssuchas wearandtearorcontamination,thesafeoperationalrangereduces. Thisreductionisdepictedbytheslantedlineinsidethe rectangle,whichshowsthenew,morerestrictedoperatingrange underdegradedconditions.Theareaabovetheslantedline20 representstherangethatcannolongerbesafelyutilizeddueto thedegradation.Thisfigureemphasizesthedynamicnatureofthe operationalrange,whichneedstobeadjustedbasedonthereal- timehealthstatusofthecompressortoensurecontinuedoperation. Forexample,thecompressormodelallowstosimulatethe25 temperatureoftheoilgivendegradationwithintheoperational rangelimits.Ifthesimulatedoiltemperatureisabovethelimit, therangecanbelimitedbasedonthesimulationsothattheoutlet temperatureislowerthanthelimit.30 BE2025 / 5066 27

[94] Accordingtothepresentinvention,asoftlimitisathreshold setforaprocessquantitythat,whenexceeded,indicatesawarning orapotentialissuethatmightnotimmediatelycompromisethe system'soperationbutcanleadtoaccelerateddegradationor reducedlifespanofcomponentsifmaintainedforanextended5 period.Softlimitsaretypicallyassociatedwithinternal setpointsandallowforsomedegreeofflexibilityinoperations tomaintaintheexternalsetpoints.

[95] Softlimitsoninternalsetpointsallowfortemporary10 deviationsthatmightcauseincreasedwearbutdonotimmediately jeopardizethesystem.Forexample,asoftlimitonmotorwinding temperaturemightpermitshort-termoperationathigher temperaturestomaintaintherequiredcompressorspeed,but prolongedoperationbeyondthislimitwouldaccelerateinsulation15 aging.

[96] Accordingtothepresentinvention,ahardlimitisastrict thresholdsetforaprocessquantitythat,whenexceeded,posesa significantrisktothesystem'ssafeoperationandrequires20 immediatecorrectiveactiontopreventdamageorfailure.Hard limitsareoftenassociatedwiththresholdsoncertaincritical processquantitiesthatmustnotbesurpassedtoensurethe system'ssafetyandreliability. 25

[97] Hardlimitsoncertaincriticalprocessquantitiesrepresent absolutemaximumvaluesthatcannotbeexceededwithoutrisking severedamage.Forinstance,themaximumallowableoiltemperature isahardlimit,beyondwhichthecompressormustbeshutdownto preventcatastrophicfailure.30 BE2025 / 5066 28

[98] Hardlimitsonexternalsetpointsensurethatthecompressor operateswithinsafeboundariessetbytheuser.Forinstance,if therequiredoutletpressureexceedsahardlimitduetosystem constraints,thecompressorwillreduceorceaseoperationto5 preventover-pressurizationandpotentialdamage.

[99] Whenahardlimitisexceededinthepresentinvention,it triggersanimmediateanddecisivereactiontoprotectthesystem. 10

[100] Inanembodimentoftheinvention,thesystemwilleither shutdownthecompressororsignificantlyreduceitsloadto preventanyfurtherincreaseintheprocessquantitythathas exceededthehardlimit.Thisistoavoidcatastrophicfailureor damagetothecompressorandassociatedcomponents.15

[101] Inanotherembodimentoftheinvention,animmediatealert isgeneratedandcommunicatedtotheoperators,maintenance personnel,orcontrolsystems.Thisalertincludesdetailsabout thespecifichardlimitthatwasexceededandthecurrentstatus20 ofthecompressor.

[102] Inanotherembodimentoftheinvention,thecompressorsystem willbepreventedfromrestartingorreturningtonormaloperation untiltheissuecausingthehardlimitbreachisresolvedandthe25 systemisverifiedtobesafeforoperation.Thisincludeschecks andconfirmationsfrommaintenancepersonnelwhennecessary. BE2025 / 5066 29

[103] Figure3isathree-dimensionalrepresentationofthe operationalrangelimits,addinganotherdimensiontotheprevious figure.Here,theaxesareambienttemperature(y-axis), compressorspeed(x-axis),andoutletpressure(z-axis).Thesolid cuboidrepresentsthenormaloperationalrangeofthecompressor5 whenitisingoodcondition.SimilartoFigure2,thedegraded conditionofthecompressorleadstoareducedoperationalrange, whichisshownasasmaller,irregularlyshapedsurfaceinsidethe cuboid.Thissurface,definedbytheinnerboundaries,represents thenewrangelimitsunderdegradedconditions.Theshapeofthis10 degradedrangeisinfluencedbytheinterplaybetweenambient temperature,speed,andoutletpressure,demonstratingthat degradationaffectsthecompressor'sperformanceinamulti- dimensionalmanner.Thisfigureillustrateshowcomplexthe limitationsbecomewhenmultiplefactorsareconsideredand15 highlightstheneedforcontinuousmonitoringandadjustmentof operationalparameterstomaintainsafeandefficientcompressor performance.

[104] Fig.4demonstrateshowthecompressor'soperationalrangeis20 adjustedbasedondegradationandoiltemperaturetoensuresafe operationwhenthecooleriscloggedby,forexample86%,according toanembodimentoftheinvention.Accordingtoanembodimentof theinvention,thedynamicadjustmentofthecompressor's operationalrangeisbasedonreal-timeassessmentsofdegradation25 andambientconditions.Bycontinuouslyadaptingthespeedlimits, thesystemensuresthatthecompressorcontinuestooperatewithin thespecifiedtemperaturelimits,evenasitagesorfacesvarying environmentalconditions.Forinstance,toensuresafecontinued operation,thecontrollermaylimitthemaximumspeedto3100rpm.30 BE2025 / 5066 30

[105] Thegraphinthefigurerepresentstherelationshipbetween themotorspeed(onthehorizontalaxis)andtheoiltemperature (ontheverticalaxis)underdifferentconditions.Also,itshows thepredeterminedambientandshutdownoiltemperatures. 5

[106] Thehealthyoiltemperaturelinerepresentstheoil temperatureovertheentirespeedrange(from1500rpmto3600 rpm)forahealthycompressoroperatingin35°Cambientair.The oiltemperaturestaysbelowthepredefinedhardlimitof70°C acrosstheentirespeedrange,indicatingthatitissafeto10 operatethecompressoratanyspeedwithinthisrangeunderthese conditions.

[107] Thecloggedoiltemperaturelinerepresentsthecomputedoil temperatureforacompressorwithacoolingcircuitthatisclogged15 by86%,alsooperatingin35°Cambientair.Forthisdegraded compressor,theoiltemperatureexceedsthe70°Climitatspeeds above3100rpm.Therefore,toensurecontinuedoperation,the controllerlimitsthemaximumspeedto3100rpm,ifinternal setpointshiftingdidnotensureacontinuingoperation.This20 preventstheoiltemperaturefromexceedingthesafethreshold, eventhoughitreducestheavailablespeedrange.

[108] Additionally,thegraphdemonstrateshowtheoperational rangecanchangewithvaryingambienttemperatures.Forexample,25 iftheambienttemperaturedropsintheeveningoratnight,the compressorcanoperateathigherspeedswithoutexceedingtheoil temperaturelimit.Thisflexibilityallowsthecompressortoadapt tochangingconditionswhilemaintainingsafeoperation. 30 BE2025 / 5066 31

[109] Figure5illustratesanexampleoftheeffectofcooler cloggingontheoperatinglimitsandinternalsetpointadjustments inthecompressorsystem.Thefigureconsistsofthreegraphs showingtherelationshipbetweenfanspeedandmotorspeedasthe degreeofcoolercloggingincreases.Thecompressorsystem5 dynamicallyadjustsitsoperatingrangebasedoninternaland externalsetpointstomaintainsafeoperatingconditions.

[110] Inthefirstgrapha),thecoolerisassumedtobeinnormal workingcondition,withoutsignificantclogging.Thefanspeedand10 motorspeedmaintainahealthyrelationshipwithinthesafe operatingdomain.Thesystemoperatesundernormalsetpoints,and theupperfanspeedlimitisrepresentedbythedashedlinelabeled "fanspeedlimit."Thislimitensuresthatthecompressorremains withinsafeoperatingmargins,preventingoverheatingorother15 operationalissues.Thislimitalsoensuresthatthefanis operatingatmaximumefficiencywiththeminimalwearofthefan.

[111] Inthesecondgraphb),representinga60%cloggedcooler, thefanspeedlimithasbeentemporarilyraised,asindicatedby20 thedashedlinelabeled"Temporaryfanspeedlimit."This adjustmentiscontrolledbythesystem’sinternalsetpoints,which areshiftedtoaccountforthedecreasedcoolingcapacityofthe system.Asthecoolerbecomesclogged,theheattransferefficiency decreases,requiringthesystemtocompensatebyincreasingfan25 speedtomaintainsafeoiltemperaturesatthehighestmotor speeds.Thesolidblacklinedepictstheadjustedrelationship betweenfanandmotorspeed,whilethedottedboundaryindicates thezerooperatingmargin;belowthisboundary,theoiltemperature wouldbecometoohighforsafeoperation.30 BE2025 / 5066 32

[112] Inthethirdgraphc),thecoolerclogginghasworsenedto 80%.Thesystem'soperatingrangehasbeenfurtherreduced,as representedbythenarrowingofthesafeoperatingdomainandthe inaccessiblemotorspeedrangeindicated.Thetemporaryfanspeed5 limithasbeenadjustedonceagaintocompensateforthereduced coolingefficiency.However,asthecloggingbecomesmoresevere, thesystemisreachingthelimitsofitsinternaladjustments.The boundarylabeled"zerooperatingmargin"iscritical;exceeding thisboundaryresultsinconditionswherethesystemcannot10 guaranteesafeoperation,potentiallyleadingtooverheatingor otherfailures.

[113] Thelimitingsetpointrangesblock,dynamicallyadjuststhe fanspeedlimitsbasedonthedegreeofcoolerclogging.Initially,15 internalsetpointshiftingoccurstocompensateforthe degradationincoolingefficiency.Ifthecloggingprogresses,and internaladjustmentsarenolongersufficient,externalsetpoints, suchasmotorspeedlimits,mayneedtobeadjustedtoprotectthe systemfromfurtherdamage.Thesystem’shealthscoringunit20 continuouslymonitorsdegradationlevels,suchascoolerclogging, andcommunicatesthisinformationtothesetpointshiftingblock andlimitingsetpointrangesblock.Thefanspeedisautomatically adjustedtomaintainoperationwithinthesafedomain,butifthe cloggingbecomesexcessive,asdepictedinthefinalgraph,the25 compressorsystemmayneedtotakeprotectiveactions,suchas reducingmotorspeedorevenshuttingdown,topreventunsafe conditions.BE2025 / 5066 33

[114] Theinventionpertainstoamethodforcontrollinga compressorsystemcomprisingacontrolunitandatleastone compressorco.

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