Series and Parallel Networks ET 162 Circuit Analysis Electrical and Telecommunication Engineering...

21
Series and Parallel Networks ET 162 Circuit Analysis Electrical and Telecommunication Engineering Technology Professor Jang

Transcript of Series and Parallel Networks ET 162 Circuit Analysis Electrical and Telecommunication Engineering...

Series and Parallel Networks

ET 162 Circuit Analysis

Electrical and Telecommunication Engineering Technology

Professor Jang

AcknowledgementAcknowledgement

I want to express my gratitude to Prentice Hall giving me the permission to use instructor’s material for developing this module. I would like to thank the Department of Electrical and Telecommunications Engineering Technology of NYCCT for giving me support to commence and complete this module. I hope this module is helpful to enhance our students’ academic performance.

OUTLINESOUTLINES

Introduction to Series-Parallel Networks Reduce and Return Approach

Block Diagram Approach

Descriptive Examples

Ladder Networks

ET162 Circuit Analysis – Series and Parallel Networks Boylestad 2

Key Words: Series-Parallel Network, Block Diagram, Ladder Network

FIGURE 7.1 Introducing the reduce and return approach.

Series-Parallel Networks –Reduce and Return

Approach

Series-parallel networks are networks that contain both series and parallel circuit configurations

For many single-source, series-parallel networks, the analysis is one that works back to the source, determines the source current, and then finds its way to the desired unknown.

ET162 Circuit Analysis – Series and parallel networks Boylestad 3

FIGURE 7.2 Introducing the block diagram approach.

Series-Parallel NetworksBlock Diagram Approach

The block diagram approach will be employed throughout to emphasize the fact that combinations of elements, not simply single resistive elements, can be in series or parallel.

ET162 Circuit Analysis – Series and parallel networks Boylestad 4

FIGURE 7.3

Ex. 7-1 If each block of Fig.7.3 were a single resistive element, the network of Fig. 7.4 might result.

mAmAIkk

IkI

mAmAIkk

IkI

ss

C

ss

B

693

2

3

2

612

12

393

1

3

1

126

6

FIGURE 7.4

ET162 Circuit Analysis – Series and parallel networks Boylestad 4

AV

R

EI

RRRN

RR

Ts

CBAT

CB

25

10

514

12

2

//

//

Ex. 7-2 It is also possible that the blocks A, B, and C of Fig. 7.2 contain the elements and configurations in Fig. 7.5. Working with each region:

2:

22

4

//:

4:

5,454

3//232

RRRRCN

R

RRRRB

RA

C

B

A

FIGURE 7.5

FIGURE 7.6ET162 Circuit Analysis Boylestad 6

AI

II

AAII

II

AII

BRR

sACB

sA

5.02

12

2

22

2

32

VVV

VARIV

VARIV

BC

BBB

AAA

2

221

842

ET162 Circuit Analysis – Series and parallel networks Boylestad 7

FIGURE 7.6

Ex. 7-3 Another possible variation of Fig. 7.2 appears in Fig. 7.7.

3

624

39

394

6.315

54

69

69

5//43

2//1

C

B

A

R

RRR

RR

AII

AV

R

EI

RRR

sA

Ts

CBAT

3

36.5

8.16

6.526.3

36

366.3//

FIGURE 7.7

FIGURE 7.8

ET162 Circuit Analysis – Series and parallel networks 8

VARIVRIV

VARIV

lawsOhmBy

AAAIII

lawcurrentsKirchhoffBy

AA

RR

IRI

yieldsruledividercurrenttheApplying

CCCBBB

AAA

BAC

BC

ACB

632

8.106.33

,'

213

,'

163

33

A

AA

III

A

A

RR

IRI

A

A

8.1

2.13

2.1

96

36

12

12

21

Series-Parallel Networks - Descriptive Examples

Ex. 7-4 Find the current I4 and the voltage V2 for the network of Fig. 7.2 .

V

V

RR

ERV

RRR

AV

R

E

R

EI

CD

D

D

B

442

122

26//3//

5.18

12

2

32

44

FIGURE 7.9

FIGURE 7.10 FIGURE 7.11ET162 Circuit Analysis – Series and parallel networks Boylestad 10

Ex. 7-5 Find the indicated currents and the voltages for the network of Fig. 7.12 .

FIGURE 7.13

8.420

96

128

128

2.15

6

23

23

32

6

5//4

3//2//1

2//1

RR

RR

N

RR

B

A

FIGURE 7.12

ET162 Circuit Analysis – Series and parallel networks Boylestad 11

ET162 Circuit Analysis – Series and parallel networks Boylestad 12

AV

R

EI

RRR

Ts

T

46

24

68.42.15//43//2//1

VARIV

VARIV

s

s

2.198.44

8.42.14

5//42

3//2//11

FIGURE 7.13

AV

R

V

R

VI

AV

R

VI

8.06

8.4

4.28

2.19

2

1

2

22

4

54

Ex. 7-6 a. Find the voltages V1, V2, and Vab for the network of Fig. 7.14. b. Calculate the source current Is.

A pplying the vo ltage d ivider ru le yields

VR E

R R

VV

VR E

R R

VV

11

1 2

33

3 4

5 1 2

5 37 5

6 1 2

6 29

.

A pplying K irchho ff s vo ltage law around

the ind ica ted loop o f F ig

V V V

V V V V V Vab

ab

'

.

. .

1 3

3 1

0

9 7 5 1 5

FIGURE 7.14a.

FIGURE 7.15

ET162 Circuit Analysis – Series and parallel networks Boylestad 13

b.B y O hm s law

IV

R

VA

IV

R

VA

' ,

..

.

11

1

33

3

7 5

51 5

9

61 5

Applying Kirchhoff’s current law,Is = I1 + I3 = 1.5A + 1.5A = 3A

ET162 Circuit Analysis – Series and parallel networks Boylestad 14

Ex. 7-7 For the network of Fig. 7.16, determine the voltages V1 and V2 and current I.

FIGURE 7.17FIGURE 7.16

V2 = – E1 = – 6V

Applying KVL to the loopE1 – V1 + E2 = 0V1 = E2 + E1 =18V + 6V = 24V

A pplying K C L to node a yields

I I I I

V

R

E

R

E

R R

V V V

A A A A

1 2 3

1

1

1

4

1

2 3

2 4

6

6

6

6

1 2

4 1 0 5 5 5

. .

ET162 Circuit Analysis – Series and parallel networks Boylestad 15

Ex. 7-9 Calculate the indicated currents and voltage of Fig.7.17.

FIGURE 7.17.

mAk

V

R

VI

VV

kk

Vk

RR

ERV

mAk

V

kk

V

RR

EI

35.45.4

6.19

6.195.16

324

125.4

725.4

324

72

1212

72

)9,8//(7

76

6)9,8//(7

)9,8//(77

54//)3,2,1(5

Is = I5 + I6 = 3 mA +4.35 mA = 7.35 mA

9 kΩ

ET162 Circuit Analysis – Series and parallel networks Boylestad 16

Ex. 7-10 This example demonstrates the power of Kirchhoff’s voltage law by determining the voltages V1, V2, and V3 for the network of Fig.7.18.

FIGURE 7.17.

F or the pa th E V E

V E E V V V

F or the pa th E V V

V E V V V V

F or the pa th V V E

V E V V V V

1 0

2 0 8 1 2

2 0

5 1 2 7

3 0

8 7 1 5

1 1 3

1 1 3

2 1 2

2 2 1

3 2 3

3 3 2

,

,

,

( )

FIGURE 7.18.

ET162 Circuit Analysis – Series and parallel networks Boylestad 17

Series-Parallel Networks – Ladder Networks

A three-section ladder appears in Fig. 7.19.

FIGURE 7.19. Ladder network.

ET162 Circuit Analysis – Series and parallel networks Boylestad 18

R

IE

R

VA

T

sT

5 3 8

2 4 0

83 0

FIGURE 7.20.

FIGURE 7.21.

ET162 Circuit Analysis – Series and parallel networks Boylestad 19

I I

II A

A

s

s

1

3 2

3 0

21 5

II

A A

V I R A V

63

6 6 6

6

6 3

6

91 5 1 0

1 0 2 2 0

ET162 Circuit Analysis – Series and parallel networks Boylestad 20