《水处理技术（双语）》课件——PID控制知识.pptxVIP

PIDcontrolknowledgePID控制知识

PID简介IntroductiontoPID比例积分微分控制，简称PID控制，是最早发展起来的控制策略之一，由于其算法简单和可靠性高，被广泛应用于工业过程控制，至今仍有90%左右的控制回路具有PID结构。PID控制，实际中也有PI和PD控制。PID控制器就是根据系统的误差，利用比例、积分、微分计算出控制量进行控制的。从信号变换的角度而言，超前校正、滞后校正、滞后－超前校正可以总结为比例、积分、微分三种运算及其组合。Proportionalintegraldifferentialcontrol,orPIDcontrolforshort,isoneoftheearliestcontrolstrategiesdeveloped,andiswidelyusedinindustrialprocesscontrolduetoitssimplealgorithmandhighreliability,andstillhasaPIDstructureinabout90%ofcontrolloops.pidcontrol,inpractice,alsohasPIandPDcontrol.PIDcontrollersarethosethatuseproportional,integralanddifferentialcalculationstocontrolthecontrolquantitiesaccordingtotheerrorofthesystem.Fromthepointofviewofsignaltransformation,overruncorrection,lagcorrectionandlag-overruncorrectioncanbesummarisedasproportional,integralanddifferentialoperationsandtheircombinations.

比例环节：即时成比例地反应控制系统的偏差信号e(t)。Proportionallink:instantproportionalresponsetothedeviationsignale(t)ofthecontrolsystem.积分环节：能对误差进行记忆，主要用于消除静差，提高系统的无差度。Integrallink:enablesthememoryoferrors,mainlyforeliminatingstaticdifferencesandimprovingthenon-differentiationofthesystem.微分环节：能反映偏差信号的变化趋势(变化速率)，并能在偏差信号值变得太大之前，在系统中引入一个有效的早期修正信号，从而加快系统的动作速度，减小调节时间。Differentiallink:reflectsthetrend(rateofchange)ofthedeviationsignalandintroducesaneffectiveearlycorrectionsignalinthesystembeforethevalueofthedeviationsignalbecomestoolarge,thusspeedinguptheactionofthesystemandreducingtheadjustmenttimePID控制器各校正环节的作用TheroleofeachcorrectionlinkofthePIDcontroller

PID控制器的参数整定是控制系统设计的核心内容。TheparameteradjustmentofthePIDcontrolleristhecoreelementofthecontrolsystemdesign.它是根据被控过程的特性确定PID控制器的比例系数、积分时间和微分时间的大小。Itisbasedonthecharacteristicsofthecontrolledprocesstodeterminethesizeofthescalefactor,integrationtimeanddifferentiationtimeofthePIDcontroller.PID参数的整定