3、ystem, cascadecontrolsystem andfeedforward controlsystemaboutthecontrolledobjectasingle watertank , anditachievesthegoalofcontrollinglevel. Foreverykindofcontrolsystem, simulationmodelisestablishedbyusingsimulationtoolMatlab,simulationcurvescananalysistheperformanceof co
4、ntrolsystem, suchasthemaximumpercentovershoot, settlingtime, attenuationrateandIAE. Thedesignof singleclosed-loopcontrol system includesdesignsofP, I, PI andPID. Thecontrollerparameteristunedbyfrequencyresponseofattenuationrateandtheattenuationcurve.Allthe controldesignme