電液比例控制技術(shù)課件：比例放大器

1/95比例放大器ProportionalAmplifier比例放大器ProportionalAmplifier6.1Summary6.2Proportionalamplifiercircuit6.3Poweramplifiercircuit6.4Proportionalamplifierpowercircuit6.5Usageandadjustmentoftheproportionalamplifier6.1概述6.2比例運(yùn)算放大器電路6.3功率放大電路6.4比例放大器的電源電路6.5比例放大器的使用及調(diào)整比例控制放大器是一種用來(lái)對(duì)比例電磁鐵提供特定性能電流，并對(duì)電液比例閥或電液比例控制系統(tǒng)進(jìn)行開(kāi)環(huán)或閉環(huán)調(diào)節(jié)的電子裝置。

Aproportionalcontrolamplifierisanelectronicdevicewhichisusedtoprovidespecificperformancecurrentwithaproportionalsolenoidvalve,andmakeopenlooporcloseloopadjustmentforanelectro-hydraulicproportionalvalveoranelectro-hydraulicproportionalcontrolsystem.6.1概述

Summary比例放大器是電液比例控制系統(tǒng)的重要組成部分，其性能及可靠性對(duì)整個(gè)系統(tǒng)起著十分重要的作用。Aproportionalamplifierisanimportantpartofanelectro-hydraulicproportionalcontrolsystemwhoseperformanceandreliabilityplaysaveryimportantroleinthewholesystem.最初的比例控制放大器設(shè)計(jì)為模擬恒壓式，控制性能較差，且多為開(kāi)環(huán)控制。而后發(fā)展為恒流式。由于恒流式能夠抑制負(fù)載阻抗熱特性的影響，并且恒流式帶鐵芯感性負(fù)載動(dòng)態(tài)性能優(yōu)于恒壓式，恒壓式逐漸被恒流式所取代。如今現(xiàn)代比例控制放大器己幾乎無(wú)一例外地采用恒流式結(jié)構(gòu)。Originalproportionalcontrolamplifiersaredesignedassimulateconstantpressuretype.Theircontrolperformanceisrelativelypoor,andmostofthemareopenloopcontrolsystems.Thentheconstantflowtypedeveloped.Duetotheconstantflowtypecaninhibiteffectsoftheheatloadimpedancecharacteristic,andtheconstantflowtypeproportionalcontrolamplifierwithironcoreperceptualloadhasbetterdynamicperformancethantheoneofconstantpressuretype.Theconstantpressuretypeisgraduallyreplacedbytheconstantflowtype.Nowmostmodernproportionalcontrolamplifiers,almostwithoutexception,usetheconstantflowstructure.6.1.1比例放大器的基本技術(shù)要求1）實(shí)現(xiàn)從電壓信號(hào)到電流信號(hào)的轉(zhuǎn)換，并提高與輸入電壓成比例且功率足夠的控制電流。2）具有足夠的功率驅(qū)動(dòng)比例電磁鐵中銜鐵上的負(fù)載，其輸入阻抗大，輸出阻抗比例電磁鐵線圈阻抗匹配。3）輸入端由各種標(biāo)準(zhǔn)信號(hào)的借口，采用標(biāo)準(zhǔn)電源。易于實(shí)現(xiàn)與不同信號(hào)發(fā)生裝置的聯(lián)結(jié)，信號(hào)的波形、幅值、頻率符合電液比例閥的靜態(tài)和動(dòng)態(tài)性能要求。6.1.1FundamentalrequirementsoftheproportionalamplifierRealizingthetransformationfromavoltagesignaltoacurrentsignal,andimprovingthecontrolelectriccurrentwhichisproportionaltotheinputvoltageandhaveenoughpower.Havingenoughpowertodriveloadsofaproportionalsolenoidarmature.Itmusthavebiginputimpedance.Itsoutputimpedancemustbematchedwithcoilimpedanceoftheproportionalsolenoid.Havinganinputterminalwithallkindsofstandardsignalsinterface,sothat,itcanbeeasytorealizeconnectionwithdifferentsignalgenerators.Itshouldusestandardpower.Thewaveform,amplitudeandfrequencyofsignalshouldaccordwithstaticanddynamicperformancerequirementsofanelectro-hydraulicproportionalvalve.6.1.1比例放大器的基本技術(shù)要求4）易于檢測(cè)控制信號(hào)和反饋信號(hào)。具有基本的故障診斷和元件保護(hù)功能。5）能產(chǎn)生正確有效的控制信號(hào)。這意味著除了有信號(hào)發(fā)生裝置外，還必須有邏輯控制與信號(hào)處理裝置。如為了減小比例元件零位死區(qū)的影響，放大器應(yīng)具有幅值可調(diào)的初始電流功能。為減小滯環(huán)的影響，放大器的輸出電流應(yīng)含有一定頻率和幅值的顫振電流分量。為減小系統(tǒng)過(guò)渡過(guò)程的沖擊，對(duì)階躍輸入信號(hào)能自動(dòng)生成速率可調(diào)的斜坡信號(hào)。6.1.1Fundamentalrequirementsoftheproportionalamplifier4)Testingandcontrollingthesignalsandfeedbacksignalseasilyandhavingbasicfaultdiagnosisandcomponentsprotectionfunctions.5)Producingacorrectandeffectivecontrolsignal.Forexample,inordertoreduceeffectsfromtheproportionalelements’Zerodead-zone,theamplifiershouldhavefunctionofmakinginitialcurrentwithadjustableamplitude.Toreduceinfluenceofhysteresis,theamplifier’soutputcurrentmustcontainacomponentofthefluttercurrentthathascertainfrequencyandamplitude.Inordertoreducetheimpactofthesystemtransitionprocess,forastepinputsignal,itcanautomaticallyproduceadjustablerateofarampsignal.6.1.2比例控制放大器的分類1）按放大器輸出控制電流的通路數(shù)可將比例放大器分為單通路和雙通路比例控制放大器。2）按放大器內(nèi)是否帶反饋通路可將比例放大器分為開(kāi)環(huán)控制和閉環(huán)控制兩種類型。3）按放大器內(nèi)運(yùn)算信號(hào)的類型可將比例放大器分為數(shù)字式和模擬式。4）按所控制比例電磁鐵的類型還有單向和雙向比例放大器。5)此外，根據(jù)比例電磁鐵控制線圈上需要恒定的信號(hào)不同分為恒壓式和恒流式比例控制放大器。6.1.2Classificationoftheproportionalamplifier1)Accordingtothenumberofcontrolledelectriccurrentrouteswhichareusedbyamplifieramplifierscanbedividedintotwotypes:single-channelandbinary-channel.Accordingtowhethertheamplifierhasfeedbackchannelsornot,itcanbedividedintotwotypes:open-loopproportionalcontrolandclosed-loopcontrol.Accordingtothetypeofsignalsinoperationamplifiers,itcanbedividedintothedigitaltypeandtheanalogtype.Accordingtothetypeofproportionalsolenoidbecontrolled,therearealsounidirectionalandbidirectionalproportionalamplifiers.6.1.3比例放大器的基本控制電路1）按放大器輸出控制電流的通路數(shù)可將比例放大器分為單通路和雙通路比例控制放大器。2）按放大器內(nèi)是否帶反饋通路可將比例放大器分為開(kāi)環(huán)控制和閉環(huán)控制兩種類型。3）按放大器內(nèi)運(yùn)算信號(hào)的類型可將比例放大器分為數(shù)字式和模擬式。4）按所控制比例電磁鐵的類型還有單向和雙向比例放大器。5)此外，根據(jù)比例電磁鐵控制線圈上需要恒定的信號(hào)不同分為恒壓式和恒流式比例控制放大器。6.13Maincircuitsoftheproportionalamplifier1)Accordingtothenumberofcontrolledelectriccurrentrouteswhichareusedbyamplifieramplifierscanbedividedintotwotypes:single-channelandbinary-channel.Accordingtowhethertheamplifierhasfeedbackchannelsornot,itcanbedividedintotwotypes:open-loopproportionalcontrolandclosed-loopcontrol.Accordingtothetypeofsignalsinoperationamplifiers,itcanbedividedintothedigitaltypeandtheanalogtype.Accordingtothetypeofproportionalsolenoidbecontrolled,therearealsounidirectionalandbidirectionalproportionalamplifiers.一個(gè)完整的比例控制放大器的典型構(gòu)成如圖，它一般由電源電路、比例放大器、控制信號(hào)發(fā)生電路、功率放大級(jí)、檢測(cè)放大電路等部分組成。圖6-1比例元件電控系統(tǒng)基本電路框圖ElectricalcontroldiagramoftheproportionalvalveAproportionalcontrolamplifierisgenerallycomposedofaproportionalamplifier,apowersupplycircuit,aprogrammingcircuitforinputtingthecontrolsignal,alogiccontrolcircuit,apoweramplifierstageandadetectionamplifiercircuit,andsoon.6.1.3比例放大器的基本控制電路1）比例放大器比例放大器又稱為電控器，是圖中的點(diǎn)劃線內(nèi)部分。它本身包含多種有特定功能的基本電路，是電氣控制系統(tǒng)的核心部分。信號(hào)的處理及放大是在比例放大器內(nèi)完成的。它與外圍電路一起構(gòu)成比例閥的電氣控制系統(tǒng)。通常它有一個(gè)或兩個(gè)輸出通道，把經(jīng)過(guò)放大的功率信號(hào)送到比例電磁鐵。6.13MaincircuitsoftheproportionalamplifierProportionalamplifierAproportionalamplifierisalsocalledanelectroniccontroller.Itisthecoreofanelectricalcontrolsystemandcontainsavarietyofspecificfunctionalbasiccircuits.Signalprocessingandamplificationarecompletedwithinaproportionalamplifier.Theproportionalamplifiertogetherwithitsperipheralcircuitsmakesupanelectricalcontrolsystemforproportionalvalves.Usuallyaproportionalamplifierhasoneortwooutputchannelswhichareusedfordeliveringamagnifiedpowersignaltotheproportionalsolenoid.6.1.3比例放大器的基本控制電路雙輸出通道的用于控制比例方向閥，單輸出通道的用于控制其它的比例元件。比例放大器通常用于力控制型比例電磁鐵，或行程控制型電磁電。用于控制后者的都帶有位置撿測(cè)反饋通道。6.13MaincircuitsoftheproportionalamplifierTheproportionalamplifierwithdoubleoutputchannelsisusedtocontrolproportionaldirectionalvalves.Thosewhichhavesinglechannelareusedtocontrolotherproportionalelements.Proportionalamplifiersaregenerallyusedforpowercontroltypeproportionalsolenoidorstrokecontroltypesolenoid.Theproportionalamplifierwhichisusedforstrokecontroltypesolenoidhasafeedbackchannelforpositiondetection.6.1.3比例放大器的基本控制電路（2）電源電路比例控制放大器電源電路的主要作用是：從標(biāo)準(zhǔn)電源中獲得分離出工作所需的各種直流穩(wěn)定電源。并且在電網(wǎng)電壓，負(fù)載電流及環(huán)境溫度允許范圍內(nèi)變化時(shí)，保證輸出直流電壓的穩(wěn)定性。同時(shí)，還兼具電源電壓極性反接、過(guò)流、短路自我保護(hù)自恢復(fù)的非熔斷式保護(hù)功能，以保證比例控制放大器的工作可靠性。6.13MaincircuitsoftheproportionalamplifierPowercircuitThemainfunctionsofthepowercircuitofaproportionalcontrolamplifieraregettingandseparatingallkindsofDCstablepowersupply,whichisneededfortheproportionalamplifierworkingregularly,fromthestandardpower,andensuringtheoutputvoltagestabilitywhenelectrifiedwirenettingvoltage,loadcurrentandambienttemperaturechangedinpermittedscope.Atthesametime,thepowercircuithasself-protectionfunctionofresistingandrecoveringfrompolarityreverseconnectedofthepowersupplyvoltage,overflowingandshoutout,sothatitcanensurefunctionalreliabilityoftheproportionalcontrolamplifier.6.1.3比例放大器的基本控制電路（3）控制信號(hào)發(fā)生電路用于產(chǎn)生給定值，作為輸入控制信號(hào)的參考值?？刂菩盘?hào)輸入電路通常采用電位器組或信號(hào)發(fā)生器來(lái)產(chǎn)生階躍變化或連續(xù)變化的控制信號(hào)。如果要求比例間跟蹤榴人信號(hào)連續(xù)變化，這時(shí)應(yīng)切除比例放大器內(nèi)的斜坡信號(hào)發(fā)生器。6.13MaincircuitsoftheproportionalamplifierAcontrolsignalinputprogrammingcircuitisusedtogenerateagivenvalueasareferencevalueoftheinputcontrolsignal.Acontrolsignalinputcircuitusuallygeneratesastepchangedorcontinuouschangedcontrolsignalbyapotentiometergrouporasignalgenerator.Ifaproportionalvalveisdemandedtotrackthecontinuouschangeoftheinputsignal,theslopesignalgeneratorintheproportionalamplifiershouldbecutoff.6.1.3比例放大器的基本控制電路（4）邏輯控制電路它的功用是協(xié)調(diào)生產(chǎn)過(guò)程對(duì)性能的要求與控制信號(hào)的生成之間的關(guān)系，實(shí)現(xiàn)整個(gè)工作過(guò)程的自動(dòng)化，并對(duì)設(shè)備提供安全措施。有些比例放大器中已包括一些繼電器組成的電路，可用于較簡(jiǎn)單的邏輯控制。復(fù)雜的邏輯控制可以外接繼電器或可編程控制器等來(lái)實(shí)現(xiàn)。6.13MaincircuitsoftheproportionalamplifierThemainfunctionofalogiccontrolcircuitiscoordinatingtherelationshipbetweenproductionprocessrequirementsonperformanceandthegenerationofcontrolsignals,realizingtheautomationofwholeworkprocess,atthesametime,supplyingsecuritymeasuresforequipments.Someproportionalamplifiershaveincludedsomecircuitscomposedbyrelaysandcanbeusedforrelativelysimplelogiccontrol.Complexlogiccontrolcanbeachievedbyconnectingexternalrelaysorprogrammablecontrollers.6.1.3比例放大器的基本控制電路（5）檢測(cè)放大電路閉環(huán)控制中傳感器檢測(cè)實(shí)際輸出值，并構(gòu)成反饋。構(gòu)成閉環(huán)有兩種形式，一種稱為閥內(nèi)閉環(huán)，常見(jiàn)的是閥芯位移的反饋；另一種稱為外閉環(huán)，是對(duì)系統(tǒng)的實(shí)際控制量的反饋。后者是閉環(huán)控制系統(tǒng)，前者對(duì)控制量來(lái)說(shuō)仍然是開(kāi)環(huán)的6.13MaincircuitsoftheproportionalamplifierApoweramplifierstageisacoreunitofaproportionalcontrolamplifier.Itsfunctionsaresynthesizingandamplifyingallkindsofcontrolsignals,andsupplyinganenoughdrivecurrentforanelectricity-mechanicaltransmission.Itusuallyrequiresadrivecurrentabout0.8~1.2foraproportionalsolenoid.6.2比例放大電路比例放大器是一種專用的電子裝置，用來(lái)對(duì)比例閥的控制電磁鐵提供特定波形的控制電流，并對(duì)整個(gè)比例閥或系統(tǒng)進(jìn)行開(kāi)環(huán)或閉環(huán)控制。所以比例放大器應(yīng)具有相應(yīng)的功能相適應(yīng)能力，以滿足生產(chǎn)上的需要。

6.2ProportionalamplifiercircuitAproportionalamplifierisadedicatedelectronicdevicewhichisusedtoprovidecontrolcurrentwhitspecificwaveformtothecontrolsolenoidofproportionalvalvesandtocontrolproportionalvalvesorthewholesystembywayofopenlooporclosed-loopcontrol.Therefore,theproportionalamplifiershouldhavecorrespondingfunctiontomeettheneedsofproduction.6.2比例放大電路

各種類型的比例放大器的內(nèi)部電路不盡相同，但它們都是由一些基本信號(hào)處理單元組成。由集成運(yùn)算放大器組成的電路，其性能比晶體管電路優(yōu)越，溫漂小，體積小，可靠性高，設(shè)計(jì)使用力便。因此，現(xiàn)代的比例控制放大器都采用由運(yùn)放組成的電路，來(lái)完成放大、振蕩、穩(wěn)壓、信號(hào)處理、比較、A/D和D/A變換等各種功能，下面對(duì)常用的基本電路作簡(jiǎn)單介紹。

6.2ProportionalamplifiercircuitElectriccircuitsinvarioustypesofproportionalamplifiersaredifferent,buttheyareallcomposedofsomebasicsignalprocessingunits.Thecircuitwhichiscomposedofanintegratedoperationalamplifierissuperiortoatransistorcircuitintermsofperformance,suchaslowertemperature-drift,smallersize,higherreliabilityandmoreconvenienttodesignanduse.Therefore,modernproportionalcontrolamplifiersmostlyadoptcircuitswhicharecomposedofoperationalamplifierstoaccomplishamplification,oscillation,voltagestabilization,signalprocess,comparison,A/DandD/Aconversionandsoon.Abriefintroductionofsomebasiccircuitsusedincommonisasfollows.6.2.1運(yùn)算放大器簡(jiǎn)介運(yùn)算放大器（常簡(jiǎn)稱為“運(yùn)放”）是具有很高放大倍數(shù)的電路單元。在實(shí)際電路中，通常結(jié)合反饋網(wǎng)絡(luò)共同組成某種功能模塊。由于早期應(yīng)用于模擬計(jì)算機(jī)中，用以實(shí)現(xiàn)數(shù)學(xué)運(yùn)算，故得名“運(yùn)算放大器”。采用集成電路工藝制做的運(yùn)算放大器，除保持了原有的很高的增益和輸入阻抗的特點(diǎn)之外，還具有精巧、廉價(jià)和可靈活使用等優(yōu)點(diǎn)，因而在有源濾波器、開(kāi)關(guān)電容電路、數(shù)-模和模-數(shù)轉(zhuǎn)換器、直流信號(hào)放大、波形的產(chǎn)生和變換，以及信號(hào)處理等方面得到十分廣泛的應(yīng)用。綜上所述，比例放大器是一個(gè)能夠?qū)θ蹼姷目刂菩盘?hào)進(jìn)行整形、運(yùn)算和功率放大的電子控制裝置

6.21Proportionaloperationamplificationcircuit6.2.2比例運(yùn)算放大電路

運(yùn)算放大器用作比例放大時(shí)，能夠?qū)崿F(xiàn)輸出量與輸入量之間線性比例關(guān)系。根據(jù)輸入信號(hào)的輸入方式不同，有反相輸入、同相輸入和差動(dòng)輸入三種形式

6.22ProportionaloperationamplificationcircuitThelinearproportionalrelationbetweenanoutputsignalandaninputsignalcanbeestablishedbyusingoperationalamplifiers.Accordingtothedifferentinputmodesoftheinputsignal,operationalamplifiercanbeclassifiedintotreetypes,whichareinvertinginput,non-invertinginputanddifferentialinput.反相放大器各種類型的比例放大器的內(nèi)部電路不盡相同，但它們都是由一些基本信號(hào)處理單元組成。由集成運(yùn)算放大器組成的電路，其性能比晶體管電路優(yōu)越，溫漂小，體積小，可靠性高，設(shè)計(jì)使用力便。因此，現(xiàn)代的比例控制放大器都采用由運(yùn)放組成的電路，來(lái)完成放大、振蕩、穩(wěn)壓、信號(hào)處理、比較、A/D和D/A變換等各種功能，下面對(duì)常用的基本電路作簡(jiǎn)單介紹。

InvertingamplifierElectriccircuitsinvarioustypesofproportionalamplifiersaredifferent,buttheyareallcomposedofsomebasicsignalprocessingunits.Thecircuitwhichiscomposedofanintegratedoperationalamplifierissuperiortoatransistorcircuitintermsofperformance,suchaslowertemperature-drift,smallersize,higherreliabilityandmoreconvenienttodesignanduse.Therefore,modernproportionalcontrolamplifiersmostlyadoptcircuitswhicharecomposedofoperationalamplifierstoaccomplishamplification,oscillation,voltagestabilization,signalprocess,comparison,A/DandD/Aconversionandsoon.Abriefintroductionofsomebasiccircuitsusedincommonisasfollows.反相放大器電路輸出電壓：可見(jiàn)，反相放大時(shí)，輸出電壓與輸入電壓之間之關(guān)系決定于比值，與放大器的放大倍數(shù)無(wú)關(guān)

InvertingamplifierTheoutputvoltageofcircuitis:Itcanbeseenthattherelationshipbetweenoutputvoltageandinputvoltageisdecidedby,whenusinginvertingamplification.Andithasnothingtodowiththeamplification圖6-2基本反向放大電路Basicreverseamplificationcircuit反相放大器如果則電路輸出電壓：在這種情況下，運(yùn)算放大器作變號(hào)運(yùn)算，稱為反相器。

Invertingamplifierifthentheoutputvoltageofcircuitis:圖6-3反向加法器Invertingsummator反相放大器

在反相放大器的輸入端安排多條支路并接，在輸出端就可實(shí)現(xiàn)多路信號(hào)線性迭加，即反相加法器，如圖示。

InvertingamplifierIfbranchesareparallelconnectedattheinputendofaninvertingamplifier,amultiplesignallinearsuperpositioncanberealizedattheoutputend.Atthistime,theinvertingamplifierisusedasaninvertingsummator,反向加法器Inverting

summator

同向放大器

同相放大器的電路如下圖所示。輸入信號(hào)從同相輸入端引入。電壓輸出：

Non-invertingamplifierAninputsignalisimportedfromthenon-invertinginputend,Theoutputvoltage圖6-4同向放大器Non-invertingamplifier

同向放大器

故輸出電壓與輸入電壓成比例，比例系數(shù)為大于等于1的正數(shù)。同相放大器的優(yōu)點(diǎn)是輸入電阻很大，一般達(dá)10MΩ以上，所以常用作電壓跟隨器。

Non-invertingamplifierSotheoutputvoltageisproportionaltotheinputvoltage.Ascalecoefficientisapositivenumberequaltoorbiggerthan1.Theadvantageofanon-invertingamplifieristhatitsinputresistanceisquitelarge,whichisgenerallymorethan10MΩ,soitisoftenusedasavoltagefollower.圖6-4同向放大器Non-invertingamplifier

同向放大器

故輸出電壓與輸入電壓成比例，比例系數(shù)為大于等于1的正數(shù)。同相放大器的優(yōu)點(diǎn)是輸入電阻很大，一般達(dá)10MΩ以上，所以常用作電壓跟隨器。

Non-invertingamplifierSotheoutputvoltageisproportionaltotheinputvoltage.Ascalecoefficientisapositivenumberequaltoorbiggerthan1.Theadvantageofanon-invertingamplifieristhatitsinputresistanceisquitelarge,whichisgenerallymorethan10MΩ,soitisoftenusedasavoltagefollower.圖6-4同向放大器Non-invertingamplifier

同向放大器

如果或（斷開(kāi)），則。即輸出電壓完全跟隨輸入電壓變化。圖6-5均為電壓跟隨器。其特點(diǎn)是輸入電阻高，輸出電阻值低，常用于阻抗變換。

Non-invertingamplifierIfor(off),then..Thatistosaytheoutputvoltagechangesfollowingtheinputvoltagecompletely.Fig.6-5showsthevoltagefollower.Thevoltagefollowerischaracterizedbyahighinputresistanceandalowoutputresistance.Soitiscommonlyusedforimpedanceconversion..圖6-5電壓跟蹤器Thevoltagefollower

差動(dòng)放大器

根據(jù)疊加原理，當(dāng)或稱為差模，稱為差模放大系數(shù)。當(dāng)時(shí)，可構(gòu)成減法器

DifferentialamplifierAccordingtotheprincipleofsuperpositionandtheabovetwoformulas,wecanobtainthat:Whenoriscalleddifferentialmode.iscalledthemagnificationcoefficientofdifferentialmode.When,adifferentialamplifiercanbeusedasasubtractor.,,6.2.3調(diào)節(jié)器電路常用的調(diào)節(jié)器電路可被稱為一種廣義反相型和同相型放大電路。反相放大器和同相放大器的輸入回路和反饋回路均為純電阻。6.2.3RegulatorcircuitCommonlyusedregulatorcircuitcanbedescribedasakindofgeneralizedinvertingandnon-invertingamplifiercircuit.Theinputcircuitandthefeedbackcircuitoftheinvertingamplifierorthenon-invertingamplifierareallpureresistancecircuit

廣義反相型電路Generalizedinvertingcircuit

,,比例放大器中常采用各種調(diào)節(jié)器，用以優(yōu)化各類閥的性能。主要任務(wù)是當(dāng)給定值發(fā)生變化時(shí)，調(diào)節(jié)控制對(duì)象的實(shí)際值與新的設(shè)定值相對(duì)應(yīng)；另一主要任務(wù)是消除或減小干擾量對(duì)調(diào)節(jié)量的影響。常用的調(diào)節(jié)器電路有比例調(diào)節(jié)器（P調(diào)節(jié)器），積分調(diào)節(jié)器（I調(diào)節(jié)器），微分調(diào)節(jié)器（D調(diào)節(jié)器），PI調(diào)節(jié)器，PD調(diào)節(jié)器,PID調(diào)節(jié)器。Avarietyofregulatorsareoftenusedinproportionalamplifierstooptimizeallkindsofvalveperformance.Themaintaskisadjustingtheobjecttocorrespondwithanewchangedgivenvalue,andanothertaskiseliminatingorreducingtheeffectsofdisturbancevariableworkingonregulatingvariable.Commonlyusedregulatorsareproportionalregulators(regulator),integralregulators(regulator),differentialregulators(regulator),regulators,regulatorsandregulators.6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit

1）比例調(diào)節(jié)器（P）比例調(diào)節(jié)器電路與反相放大器的電路完全相同，輸入量與輸出量的關(guān)系：令即得比例調(diào)節(jié)器的比例系數(shù)。

Aproportionalregulatorcircuitiscompletelythesamewithaninvertingamplifiercircuit.Therelationbetweeninputandoutputquantityis:Ordernamelytheproportionalitycoefficientofaproportionalregulator.6.2.3Regulatorcircuit6.2.3調(diào)節(jié)器電路,,2）積分調(diào)節(jié)器（I）在P調(diào)節(jié)器的反饋電路中，用電容代替反饋電阻就可獲得積分調(diào)節(jié)器。電壓輸出為：

AnintegralregulatorcanbeacquiredbywayofusingacapacitanceinsteadofafeedbackresistanceinthefeedbackofaPregulator.Theoutputvoltageis:

圖6-8積分調(diào)節(jié)器及階躍響應(yīng)特性

a)積分調(diào)節(jié)器b)節(jié)約響應(yīng)特性

Integralregulatoranditsstepresponsecharacteristics

a.Integralcontrollerb.Stepresponsecharacteristic6.2.3調(diào)節(jié)器電路6.2.3RegulatorcircuitSetupasastepfunction,,iftheinitialvalueiszero,thentheoutputvoltageis:Fromtheformula,willlinearincreaseastheslopethetransitionprocessisasshowninFig.6-8b.設(shè)為階躍函數(shù),若初始值為零，則輸出電壓為由式可知，將以斜率線性遞增，其過(guò)渡過(guò)程如圖6-8b所示6.2.3Regulatorcircuit6.2.3調(diào)節(jié)器電路Anintegralregulatorhasfunctionsofdelay,accumulationandmemory.Theso-calleddelayfunctionisthatanoutputsignalcanonlygraduallychanginginspiteofthefastchangeoftheinputsignal.Thisfeaturecanbeusedasarampup-downregulatingcircuit.Theso-calledaccumulationfunctionisthattheaccumulationwillnotstopaslongastheinputexists.Thisfeaturecanbeusedtoeliminatesystematicerrors.Theso-calledmemoryfunctionmeansthattheinputsuddenlydisappears,buttheoutputkeepsoriginalvalueandremainsthesame.積分調(diào)節(jié)器具有延緩、積累和記憶功能。所謂延緩功能是輸入變化很快，但輸出信號(hào)只能漸變，這一特性可用作為斜坡上升、下降調(diào)節(jié)電路。所謂積累功能是只要輸入存在，積累就不停止，這一特性可用來(lái)消除系統(tǒng)誤差。所謂記憶功能是指輸入突然消失后，其輸出保持原值不變。6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit,,3）微分調(diào)節(jié)器（D）微分是積分的逆運(yùn)算，將積分電路中和C對(duì)調(diào)就構(gòu)成純微分調(diào)節(jié)器。但純微分調(diào)節(jié)器在固有頻率附近會(huì)出現(xiàn)諧振，使系統(tǒng)不穩(wěn)定。Itisknowntoallthatdifferentialisinverseofintegral.ApuredifferentialregulatorcanbeachievedthroughputtingandCreversedinanintegralcircuit.Thepuredifferentialregulatormayappearresonancenearthenaturalfrequency,sothatmakethesystemunstable.

圖6-9微分調(diào)節(jié)器及其單位階躍響應(yīng)特性

a)微分調(diào)節(jié)器b)單位階躍響應(yīng)特性Differentialregulatorcircuitanditsunitstepresponsea).Differentialregulatorb).Unitstepresponse6.2.3Regulatorcircuit6.2.3調(diào)節(jié)器電路,,為此，在輸入端串聯(lián)一個(gè)電阻（形成小阻尼），以提高穩(wěn)定性。采取補(bǔ)償措施后的微分調(diào)節(jié)器電路如圖所示。Forthisreason,aresistanceneedstobeconnectedinseriesintheinputendtopromotestability.Thedifferentialregulatorcircuitaftertakingindemnifyingmeasuresisshowninfigure

圖6-9微分調(diào)節(jié)器及其單位階躍響應(yīng)特性

a)微分調(diào)節(jié)器b)單位階躍響應(yīng)特性Differentialregulatorcircuitanditsunitstepresponsea).Differentialregulatorb).Unitstepresponse6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit,,

設(shè)輸入為單位階躍信號(hào)，即初值為零，輸出電壓的時(shí)間響應(yīng)函數(shù)為其過(guò)渡特性如圖6-9b所示。顯然，D調(diào)節(jié)器只會(huì)對(duì)變化著的信號(hào)產(chǎn)生響應(yīng)，對(duì)固定不變的輸入不會(huì)有微分作用。Supposingaunitstepsignalastheinputsignal,thatmeans,whoseinitialvalueiszero.Thetimeresponsefunctionoftheoutputvoltageis:ThetransitioncharacteristicsareshowninFig.6-26b.Apparently,theDregulatorwillonlyrespondtochangingsignals,buttoafixedinputwillnothavedifferentialeffects.6.2.3Regulatorcircuit6.2.3調(diào)節(jié)器電路,,所以微分作用是高通電路，對(duì)高頻干擾和噪聲反應(yīng)很靈敏，容易產(chǎn)生自激振蕩，使用時(shí)應(yīng)增加以增大阻尼，限制高頻增益。微分作用在信號(hào)變化快時(shí)給出較大的控制量，這有利于改善動(dòng)態(tài)偏差和減小過(guò)渡時(shí)間；但微分作用不能克服靜誤差，且微分作用過(guò)強(qiáng)時(shí)，系統(tǒng)不易穩(wěn)定。通常它與P、I調(diào)節(jié)器構(gòu)成復(fù)合調(diào)節(jié)器使用。Therefore,thedifferentialeffectcircuitisahighpasscircuit.Itissensitivetohigh-frequencyinterferenceandnoiseresponse,anditcanproduceself-oscillationeasily.Soshouldbeincreasedtomagnifydampingtolimithigh-frequencygain.Thedifferentialactionwillproducealargercontrolvariablewhichishelpfultoimprovedynamicdeviationandreducethetimeoftransitionwhenthesignalisrapidlychanging.However,differentialeffectscannotovercomestaticerror,andwhenthedifferentialeffectistoostrong,thesystemcannotstabilizeeasily.Usually,acomplexregulatorisusedwhichiscomposedofPandIregulator.6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit,,4）PI調(diào)節(jié)器P調(diào)節(jié)器的初始特性好，對(duì)輸入量反應(yīng)很快，但有殘留誤差；I調(diào)節(jié)器的完成特性好，調(diào)節(jié)偏差為零。兩個(gè)調(diào)節(jié)器聯(lián)合所得到的特性能夠保留二者的優(yōu)點(diǎn)。PI調(diào)節(jié)器如圖所示。InitialcharacteristicsofaPregulatoraregood.ThePregulatorhasaquickresponsetoaninputquantity,butithastheresidualerror.AnIregulatorhasagoodcharacteristicofcompletionanditsadjustingdeviationiszero.APIregulatorwhichisacombinationofthetworegulatorshascharacteristicsoftheboth.TheregulatorisshowninFig.6-10

圖6-10PI調(diào)節(jié)器及其階躍響應(yīng)特性a)PI調(diào)節(jié)器b)階躍響應(yīng)特性PIregulatoranditsstepresponsecharacteristicsa).PIregulatorb).Unitstepresponsecharacteristics6.2.3Regulatorcircuit6.2.3調(diào)節(jié)器電路,,5）PD調(diào)節(jié)器

PD調(diào)節(jié)器對(duì)快速變化的輸入信號(hào)作出超前響應(yīng)，因而可以加速調(diào)節(jié)過(guò)程。但由于沒(méi)有積分I作用，仍存在一個(gè)靜態(tài)偏差。ThePDregulatorcanmakeadvancedresponsetoaquicklychangedinputsignal,soitcanspeeduptheregulatingprocess.BecausethePDregulatorlacksofthefunctionofintegralI,itstillhasastaticdeviation.圖6-11PD調(diào)節(jié)器

ThePDregulator6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit,,6）PID調(diào)節(jié)器PID調(diào)節(jié)器性能良好，使用廣泛。將其放大系數(shù)設(shè)計(jì)成可調(diào)，就可以適用于各種調(diào)節(jié)對(duì)象。構(gòu)成PID調(diào)節(jié)器的方案很多，圖6-12是比例放大器中廣泛采用的一種方案。該方案的特點(diǎn)是可根據(jù)需要方便地取舍P、I、D中的任一個(gè)環(huán)節(jié)，每一個(gè)環(huán)節(jié)的時(shí)間常數(shù)獨(dú)立可調(diào)，互不影響。該方案通過(guò)加法電路將獨(dú)立的P、I、D電路疊加在一起。APIDregulatorhasgoodperformance,soitiswidelyused.APIDregulatorcanbeusedinallkindsofcontrolledplant,ifitsmagnificationcoefficientisdesignedadjustable.TherearemanyschemesofaPIDregulatorconstitution.OneofthemwhichiswidelyusedinaproportionalamplifierisshowninFig.6-12ThecharacteristicofthisschemeisthatwecanacceptorrejectanyelementofP,IandDconvenientlyaccordingtoneed.Thetimeconstantofeachelementisadjustableindependentlyandwithoutinterference.TheP,IandDcircuitareaddedtogetherbyusingaddedcircuitshowninthisscheme..6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit圖6-12常用的PID調(diào)節(jié)器電路

a)電路b)特性ThePIDregulatorcircuitanditscharacteristicsa.The

circuit

b.Characteristics6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit

設(shè)其傳遞函數(shù)為式中—比例環(huán)節(jié)的比例放大系數(shù)，

—積分環(huán)節(jié)的比例放大系數(shù)，

—積分環(huán)節(jié)中慣性環(huán)節(jié)的時(shí)間常數(shù)SetthePIDregulator’stransformfunctionis——theproportionamplificationcoefficientoftheproportionallink——theproportionamplificationcoefficientoftheintegrallink——thetimeconstantoftheinertiaelementinintegrallink6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit

—積分環(huán)節(jié)的時(shí)間常數(shù)，

注意到，故相當(dāng)于積分環(huán)節(jié)

—微分環(huán)節(jié)的比例放大系數(shù)，

—微分環(huán)節(jié)的時(shí)間常數(shù)，式中的各項(xiàng)系數(shù)是根據(jù)系統(tǒng)校正的需要配置的。

——Thetimeconstantoftheintegrallink

considering,soisequivalenttotheintegrallink——Theproportionamplificationcoefficientofthedifferentiallink——thetimeconstantoftheproportionallink6.2.3調(diào)節(jié)器電路6.2.3Regulatorcircuit

6.2.4控制信號(hào)發(fā)生電路本質(zhì)上是向比例放大器提供參考電壓，作為輸入控制信號(hào)。對(duì)于開(kāi)環(huán)系統(tǒng)，它就是實(shí)際的控制輸入，對(duì)于閉環(huán)系統(tǒng)，它還要與反饋信號(hào)比較，得出的偏差值才是真正的控制信號(hào)。

ControlsignalgenerationcircuitEssentially,areferencevoltageisprovidedtoaproportionalamplifierasaninputcontrolsignal.Foranopen-loopsystem,itisanactualcontrolinput.Butforaclosed-loopsystem,itneedstocomparewithafeedbacksignal,andtheobtaineddeviationistheactualcontrolsignal.

比例放大器的信號(hào)發(fā)生電路可用于形成比例放大器的指令信號(hào)，即給定信號(hào)，以滿足設(shè)備工況要求，也可用于改善控制元件的性能，例如為了改善系統(tǒng)的啟動(dòng)和停止性能，設(shè)有斜坡信號(hào)發(fā)生器活專門的函數(shù)信號(hào)發(fā)生器。

Proportionalamplifiercanuseasignalgeneratingcircuittoproduceacommandsignaltomeettherequirementsoftheworkingconditionofequipment,anditcanalsobeusedtoimprovetheperformanceofcontrolcomponents.Forexample,inordertoimprovethestart-stopperformanceofasystem,generallyarampsignalgeneratororaspecialfunctionsignalgeneratorisinstalledinthesystem.6.2.4控制信號(hào)發(fā)生電路

Controlsignalgenerationcircuit

1）斜坡信號(hào)發(fā)生器斜坡信號(hào)發(fā)生器用于控制信號(hào)的上升變化和下降變化速度，使當(dāng)輸入階躍信號(hào)時(shí)，能夠以可調(diào)的速率無(wú)沖擊地到達(dá)給定值要求，從而獲得平穩(wěn)而迅速的起動(dòng)、轉(zhuǎn)換或停止，進(jìn)而提高生產(chǎn)率。圖6-13所示是將階躍信號(hào)轉(zhuǎn)換為斜坡信號(hào)的典型電路。

Aslopesignalgeneratorisusedtocontrolthespeedofrisechangeanddeclinechange.Whenastepsignalisinput,itcanreachgivenvaluerequirementsatadjustablespeedwithoutimpact,soastoobtainasmoothandrapidstart,transmissionorstop,andimproveproductivity.6.2.4控制信號(hào)發(fā)生電路

Controlsignalgenerationcircuit圖6-13斜坡信號(hào)發(fā)生器電路a)斜坡信號(hào)發(fā)生電路b)斜坡信號(hào)發(fā)生電路的輸入輸出特性a)b)Slopesignalgenerationcircuita)Slopesignalsgenerationcircuitb)Input