TheveninThevenin vs. Nortonvs. Norton

2012411

TheveninTheveninEquivalent CircuitEquivalent Circuit

NortonNortonEquivalent CircuitEquivalent Circuit

TheveninThevenin theoremtheorem

TheveninThevenin18831883

EEThThRRThTh

Norton theoremNorton theorem19261926HauseHause--

SiemensSiemens

IInnRRNN

RRThTh

RRThTh

EEThTh1/21/2

EEThTh

EEThTh2/22/2

RRNN==RRThTh

RRNN

75.3R//)RR(R 321N

iiNN1/21/2

iiSCSCiiNN

iiNN2/22/2

A667.215

V40RR

Ei21

N

A143.1RR

RiiLN

NNL

General MethodGeneral Method

Is

IL

A143.1RR

RII

A286.2REI

5.17RR)R//R(R

L3

3SL

TS

213LT

Source ConversionSource Conversion

RRNN==RRThTh

NNThTh

ThN RiER

Ei

Application Application 1/21/2

TheveninTheveninNortonNorton

Application Application 2/22/2

RTH = RN = ETHIN

ammetervoltmeter

15

Experimental Determination of Experimental Determination of TheveninTheveninand Norton Equivalentsand Norton Equivalents

TH

mSCN

Rr1II

16

Experimental Determination of Experimental Determination of TheveninTheveninand Norton Equivalentsand Norton Equivalents

m

THOCTH

rR1VE

17

ExampleExample

mSC

OC

N

THTH

TH

mSCN

OCTH

rIV

IER

Rr1II

V5.6VE

The unknown circuit is replaced by its Theveninequivalent.

Measured VOC=6.5V Measured ISC=3.75mA rm=15

Maximum Power TransferMaximum Power Transfer

supplysupply RRL L = = RRThTh supplysupply

RL=0.5RTh RL=1.5 RThPower

Exercise 20 Exercise 20 TheveninThevenin networknetwork

RTH

333.1R//)R//R(R 321TH

ETH

ETH

I3

A1985.26.9V21

REI

6.9R)R//R(R

Ts

123T

V5.3RIE

A4375.0RR

RII

33TH

32

2S3

IS

Thvenin Network

333.1RTH

V5.3ETH

W721.1RIP

A656.0)4333.1(

V5.3RR

EI

L2

L

LTH

THL

Exercise 21 Exercise 21 TheveninThevenin networknetwork

SolutionSolution

W721.1RIP

A656.0)4333.1(

V5.3RR

EI

L2

L

LTH

THL

RRL L = R= RTH TH = 1.333= 1.333

W297.2R4

ER4

EW297.2RIP

A3125.1)333.1333.1(

V5.3RR

EI

TH

2TH

L

2TH

L2

L

LTH

THL

Exercise 22 Exercise 22 TheveninThevenin networknetwork

,

RTH

8R//)R12(R 32TH

ETH

ETH

V38RR12

R)E'E(E32

3TH

Thvenin Network

38V

8

RRL L = R= RTH TH = 8= 8

W125.45R4

ER4

EPTH

2TH

L

2TH

max