【精品】现代控制理论.pptx

现代控制理论

ModernControlTheory

刘向杰

Email:liuxj@ncepu.edu.cn

华北电力大学自动化系

DepartmentofAutomation

NorthChinaElectricPowerUniversity

ModernControlTheory

NCEPU

■1.1Motivation

mWhatisasystem?

·Aphysicalprocessoramathematicalmodelofa

physicalprocessthatrelatesonesetofsignalsto

anothersetofsignalstion/se/

·Twogeneralcategoriesofsignals/systems:

-Continuous-time(CT)signals/systems

·Examples:Speed/car,current/circuit,temperature/room

·Describedbydifferentialeqs.,e.g.,dy/dt=ay(t)+bu(t)

·Signalsthemselvescouldbediscontinuous.Butdefined

foreachtimeinstant.

n

t/

o

u

resp

outp

a

/

it

ut

exc

inp

causeSystemresult

-Examples:Airconditioner,cars,circuits,bankaccounts

ModernControlTheoryChapter1Introduction

DepartmentofAutomation

NorthChinaElectricPowerUniversity

NCEPU

-Discrete-time(DT)signals/systems

·Examples:Moneyinabankaccount,quarterlyprofit·Sequenceofnumbers

·Input/outputrelatedbydifferenceequations,e.g.,

y[k+1]=ay[k]+bu[k],(onadailyormonthlybase)

-DTandCTarequitesimilar,andwillbetreatedinparallel

·ThegoalofSystemTheory?

-Establishinput/outputrelationshipthroughmodels,

-Predictoutputfrominput,knowhowtoproducedesiredoutput

-Alterinputautomatically(viacontroller)toproduce

ModernControlTheoryChapter1Introduction

DepartmentofAutomation

NorthChinaElectricPowerUniversity

input→[System

NCEPU

output

k

·Usephysicallawstomodel/describethebehaviorofthesystem:

·Whatarethecomponents?Whatpropertiesdotheyhave?

Vg=Rig,

-Relationshipamongthevariablesbyphysicallaw:

·KCL:Currenttoanode=0,ig=ic=iL=i.

·KVL:Voltageacrossaloop=0.

ModernControlTheory