Selectionofcontrolledparameters被控參數(shù)的選擇落版在此被控參數(shù)的選擇Selectionofcontrolledparameters謝聰XieCong主講教師Teacher核心Core控制系統(tǒng)方案設(shè)計(jì)Controlsystemschemedesign被控參數(shù)的選擇Selectionofcontrolledparameters被控參數(shù)Controlledparameter被控參數(shù)的選擇Selectionofcontrolledparameters被控參數(shù)Controlledparameter過程控制ProcesscontrolThecoreconceptofselectingcontrolledparameters被控參數(shù)選擇的核心概念Thecoreconceptofselectingcontrolledparameters被控參數(shù)選擇的核心概念生產(chǎn)過程中希望借助自動(dòng)控制保持恒定值（或按一定規(guī)律變化）的過程參數(shù)（變量）。Aprocessparameter(variable)thatneedstobemaintainedataconstantvalue(orchangefollowingacertainpattern)throughautomaticcontrolduringproduction.被控參數(shù)（或變量）Controlledparameter(orvariable)Thecoreconceptofselectingcontrolledparameters被控參數(shù)選擇的核心概念合理選擇被控參數(shù)：Properselectionofcontrolledparameters:關(guān)系到生產(chǎn)工藝和生產(chǎn)過程能否達(dá)到保證安全、穩(wěn)定操作、保證質(zhì)量和經(jīng)濟(jì)效益等目的。Crucialforensuringsafetyandstableoperation,qualityassurance,andeconomicbenefitsintheproductionprocess.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則原則一PrincipleI根據(jù)生產(chǎn)工藝的要求，找出影響生產(chǎn)的關(guān)鍵變量作為被控參數(shù)。Identifykeyvariablesaffectingproductionascontrolledparametersbasedonprocessrequirements.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例儲(chǔ)槽液位控制系統(tǒng)Forexample:storagetanklevelcontrolsystemLCTTh生產(chǎn)工藝要求儲(chǔ)槽液位穩(wěn)定Theproductionprocessrequiresstabletanklevel設(shè)計(jì)的控制系統(tǒng)就應(yīng)以儲(chǔ)槽液位為被控參數(shù)。Thecontrolsystemshouldbedesignedwiththetanklevelasthecontrolledparameter.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例換熱器出口溫度控制系統(tǒng)Forexample：heatexchangeroutlettemperaturecontrolsystem熱物料Hotmaterial載熱介質(zhì)Heat-carryingmedia冷物料Coldmaterial熱交換器HeatexchangerTTTTTCTC生產(chǎn)工藝要求換熱器出口熱物料溫度為定值Theproductionprocessrequirestheoutlettemperatureofthehotmaterialfromtheheatexchangertobeaconstantvalue.設(shè)計(jì)控制系統(tǒng)就應(yīng)以換熱器出口熱物料溫度為被控參數(shù)。Thecontrolsystemshouldbedesignedwiththeoutlettemperatureofthehotmaterialasthecontrolledparameter.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則原則二PrincipleII當(dāng)直接工藝參數(shù)不能作為被控參數(shù)時(shí)，應(yīng)選擇與直接工藝變量有單值函數(shù)關(guān)系的工藝變量作為間接被控參數(shù)。Whenadirectprocessparametercannotserveasthecontrolledparameter,aprocessvariablewithanuniformfunctionrelationshiptothedirectprocessvariableshouldbeselectedastheindirectlycontrolledparameter.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例化工的精餾物純度控制系統(tǒng)Forexample:Puritycontrolsystemforchemicaldistillate冷卻介質(zhì)Coolingmedia進(jìn)料Feeding回流RefluxOverheadproduct(componentconcentrationxd)Distillationcolumn加熱蒸汽HeatingsteamCondensateSteamheaterBottomproduct(componentconcentrationxw)苯Benzene甲苯Toluene苯—甲苯Benzene-toluene將苯—甲苯混合液進(jìn)行分離separateabenzene-toluenemixture精餾工藝是利用被分離混合物各組分的揮發(fā)溫度不同，將各組分分離。Distillationtechnologyistoseparatecomponentsofamixturebyutilizingdifferencesintheirvolatilizationtemperatures.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例化工的精餾物純度控制系統(tǒng)Forexample:Puritycontrolsystemforchemicaldistillate分離核心Coreprincipleofseparation冷卻介質(zhì)Coolingmedia進(jìn)料Feeding回流RefluxOverheadproduct(componentconcentrationxd)Distillationcolumn加熱蒸汽HeatingsteamCondensateSteamheaterBottomproduct(componentconcentrationxw)苯Benzene甲苯Toluene苯—甲苯Benzene-toluene利用兩者沸點(diǎn)的差異實(shí)現(xiàn)分離Achieveseparationbyutilizingthedifferenceinboilingpoints在標(biāo)準(zhǔn)大氣壓下：苯的沸點(diǎn)約為80.1℃，甲苯的沸點(diǎn)約為110.6℃，兩者存在明顯的沸點(diǎn)差。Understandardatmosphericpressure:benzeneboilsatapproximately80.1°C,whiletolueneboilsatapproximately110.6°C,showingasignificantboilingpointdifference.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例化工的精餾物純度控制系統(tǒng)Forexample:Puritycontrolsystemforchemicaldistillate冷卻介質(zhì)Coolingmedia進(jìn)料Feeding回流RefluxOverheadproduct(componentconcentrationxd)Distillationcolumn加熱蒸汽HeatingsteamCondensateSteamheaterBottomproduct(componentconcentrationxw)苯Benzene甲苯Toluene苯—甲苯Benzene-toluene精餾塔的工藝目標(biāo)Processobjectivesofthedistillationcolumn塔頂（或塔底）餾出物達(dá)到規(guī)定的純度。按照被控變量的選擇原則1，塔頂（或塔底）餾出物的組分應(yīng)作為被控變量。Theoverhead(orbottom)distillatemustmeetspecifiedpurityrequirements.AccordingtoPrincipleIforselectingthecontrolledvariable,thecomponentoftheoverhead(orbottom)distillateshouldbeusedasthecontrolledvariable.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例化工的精餾物純度控制系統(tǒng)Forexample:Puritycontrolsystemforchemicaldistillate冷卻介質(zhì)Coolingmedia進(jìn)料Feeding回流RefluxOverheadproduct(componentconcentrationxd)Distillationcolumn加熱蒸汽HeatingsteamCondensateSteamheaterBottomproduct(componentconcentrationxw)苯Benzene甲苯Toluene苯—甲苯Benzene-toluene沒有合適的儀表在線檢測(cè)餾出物的純度Thereisnosuitableinstrumentforonlinedetectionofdistillatepurity不能作為直接被控參數(shù)itcannotserveasthedirectcontrolledparameter.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例化工的精餾物純度控制系統(tǒng)Forexample:Puritycontrolsystemforchemicaldistillate冷卻介質(zhì)Coolingmedia進(jìn)料Feeding回流RefluxOverheadproduct(componentconcentrationxd)Distillationcolumn加熱蒸汽HeatingsteamCondensateSteamheaterBottomproduct(componentconcentrationxw)苯Benzene甲苯Toluene苯—甲苯Benzene-toluene只能在與餾出物的純度有單值關(guān)系的工藝參數(shù)中，找出合適的變量作為被控變量，進(jìn)行間接參數(shù)控制。Onlyamongtheprocessparameterswithanuniformfunctionrelationshiptothedistillatepuritycanasuitablevariablebeselectedasthecontrolledvariableforindirectparametercontrol.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則例化工的精餾物純度控制系統(tǒng)Forexample:Puritycontrolsystemforchemicaldistillate冷卻介質(zhì)Coolingmedia進(jìn)料Feeding回流RefluxOverheadproduct(componentconcentrationxd)Distillationcolumn加熱蒸汽HeatingsteamCondensateSteamheaterBottomproduct(componentconcentrationxw)苯Benzene甲苯Toluene苯—甲苯Benzene-toluene經(jīng)工藝分析發(fā)現(xiàn)Processanalysisreveals塔內(nèi)壓力和塔內(nèi)溫度都對(duì)餾出物純度有影響B(tài)othcolumnpressureandcolumntemperatureaffectdistillatepurity需要對(duì)二者進(jìn)行比較試驗(yàn)，選出一個(gè)合適的變量作為間接被控參數(shù)。Comparativetestsareneededforcolumnpressureandcolumntemperaturetoselectanappropriatevariableastheindirectlycontrolledparameter.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則間接被控參數(shù)的確定：Determinationofindirectlycontrolledparameters:經(jīng)試驗(yàn)得出：塔頂餾出物苯的濃度分別與壓力和溫度有單值對(duì)應(yīng)關(guān)系。（塔底餾出物甲苯也一樣）Experimentsshowthat:theconcentrationofbenzeneintheoverheaddistillatehasanuniformfunctionrelationshipwithpressureandtemperaturerespectively.(Italsoappliestotolueneinthebottomdistillate)Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則間接被控參數(shù)的確定：Determinationofindirectlycontrolledparameters:從工藝合理性考慮Fromaprocessrationalityperspective選擇溫度作為間接被控參數(shù)，實(shí)現(xiàn)對(duì)塔頂餾出物苯的純度的間接控制。Temperatureisselectedastheindirectlycontrolledparametertoachieveindirectcontroloverthepurityofbenzeneintheoverheaddistillate.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則原則三PrincipleIII被控參數(shù)必須靈敏，容易被測(cè)量。Thecontrolledparametermustbesensitiveandeasilymeasurable.被控參數(shù)必須有足夠高的靈敏度Thecontrolledparametermusthavesufficientlyhighsensitivity原則四PrincipleIV壓力穩(wěn)定通常是保證溫度與純度單值對(duì)應(yīng)關(guān)系的前提，而溫度對(duì)餾出物純度的變化更敏感。Stablepressureisusuallyaprerequisiteforensuringtheuniformfunctionrelationshipbetweentemperatureandpurity.Moreover,temperatureismoresensitivetochangesindistillatepurity.選擇被控參數(shù)(變量)時(shí)，必須考慮工藝合理性。Processrationalitymustbeconsideredwhenselectingcontrolledparameters(variables)原則五PrincipleV必須考慮過程檢測(cè)控制儀表及裝置的現(xiàn)狀Thecurrentstatusofcontrolinstrumentsanddevicesforprocessdetectionmustbeconsidered.Principlesforselectingcontrolledparameters選擇被控參數(shù)的原則優(yōu)先選擇對(duì)產(chǎn)品的產(chǎn)量和質(zhì)量、安全生產(chǎn)、經(jīng)濟(jì)運(yùn)行和環(huán)境保護(hù)具有決定性作用的、可直接測(cè)量的工藝參數(shù)為被控參數(shù)。Priorityshouldbegiventoselectingdirectlymeasurableprocessparametersthataredecisiveforproductyield,quality,safety,economicaloperationandenvironmentalprotectionascontrolledparameters.當(dāng)不能用直接參數(shù)作為被控參數(shù)時(shí)，應(yīng)該選擇一個(gè)與直接參數(shù)有單值函數(shù)關(guān)系的間接參數(shù)作為被控參數(shù)。Whendirectparameterscannotbeusedascontrolledparameters,anindirectparameterwithanuniformfunctionrelationshiptothedirectparametershouldbeselectedasthecontrolledparameter.被控參數(shù)必須具有足夠高的靈敏度。Thecontrolledparametermusthavesufficientlyhighsensitivity.被控參數(shù)的選取，必須考慮工藝過程的合理性。Therationalityoftheprocessmustbeconsideredintheselectionofcontrolledparameters.必須考慮過程檢測(cè)控制儀表及裝置的現(xiàn)狀。Thecurrentstatusofcontrolinstrumentsanddevicesforprocessdetectionmustbeconsidered.總結(jié)：Summary:被控參數(shù)的選擇Selectionofcontrolledparameters被控參數(shù)的選擇Selectionofcont