Thesis Title (English)

Student Name

THESIS SUBMITTED IN FULFILMENT OF THE DEGREE OF

DOCTOR OF PHILOSOPHY

FACULTY OF ENGINEERING AND BUILT ENVIROMENT

UNIVERSITI KEBANGSAAN MALAYSIA

BANGI

2011

ii

Thesis Title (Malay)

Student Name

TESIS YANG DIKEMUKAKAN UNTUK MEMPEROLEH IJAZAH

DOKTOR FALSAFAH

FAKULTI KEJURUTERAAN DAN ALAM BINA

UNIVERSITI KEBANGSAAN MALAYSIA

BANGI

2011

iii

DECLARATION

I hereby declare that the work in this thesis is my own except for quotations and

summaries which have been duly acknowledged.

Date Student Name

Student Number

iv

ACKNOWLEDGMENTS

First and foremost praise be to Almighty Allah for all his blessings for giving me

patience and good health throughout the duration of this PhD research.

I am very fortunate to have Professor Dr. … as a research supervisor.

Also, I would like to express my high appreciation to my co-supervisor Dr. …

Moreover, I am grateful to

I would like to thank all post graduate students of UKM power research group

for their help, friendship, and creating a pleasant working environment throughout my

years in UKM.

To my dearest wife

Last but not least, I gratefully acknowledge financial support provided by

UKM under grant numbers

v

ABSTRACT

The recent changes in utility structures, development in renewable technologies and

increased

vi

ABSTRAK

Perubahan terkini dalam struktur utiliti, kemajuan teknologi boleh diperbaharui dan

peningkatan

vii

TABLE OF CONTENTS

Page

DECLARATION iii

ACKNOWLEDGMENTS iv

ABSTRACT v

ABSTRAK vi

CONTENTS vii

LIST OF TABLES x

LIST OF FIGURES xii

LIST OF ABBREVIATIONS xv

LIST OF SYMBOLS xvi

CHAPTER I INTRODUCTION

1.1 Research Background 1

1.2 Problem Statement 1

1.3 Objectives of Research and Scope of Works 1

CHAPTER II LITERATURE REVIEW

2.1 Distributed Generation 2

2.1.1 Distributed Generation 2

2.1.2 Effect of Distributed Generation 2

2.2 Protection Issues for Distribution Networks

2.2.1 Short Circuit Currents 3

2.2.2 Power Flow 3

2.2.3 Overcurrent Protection 3

2.3 Distribution Systems 3

2.3.1 Review of Distribution Networks 3

2.4 Review of Distributed Generation 3

2.4.1 Distribution System Protection 3

viii

2.4.2 Review of Protection Methods 3

2.5 Chapter Summary 4

CHAPTER III DISTRIBUTION NETWORK

3.1 Introduction 5

3.2 Radial Basis Function Neural Network 5

3.3 Distribution Network 5

3.3.1 Network 5

3.3.2 Classification 5

3.3.3 Location 5

3.3.4 Determination 6

3.3.5 Restoration 6

3.3.6 Generation 6

3.4 Chapter Summary 6

CHAPTER IV PROTECTION STATEGY

4.1 Introduction 7

4.2 Protection 7

4.2.1 Main and Backup 7

4.2.2 Device 7

4.3 Algorithm 7

4.4 Proposed Strategy 7

4.4.1 Main Algorithm 8

4.4.2 Backup Algorithm 8

4.5 Chapter Summary 8

CHAPTER V RESULTS AND DISCUSSION

5.1 Results of 9

5.1.1 14 Bus Test System 9

5.1.2 22 Bus Test System 10

5.1.3 32 Bus Test System 10

5.1.4 Results for Location 11

5.2 Results of Strategy 11

5.2.1 Results of Strategy for the 14 bus test system 11

ix

5.2.2 Results of Strategy for the 22 bus test system 11

5.2.3 Results of Strategy for the 32 bus test system 11

5.3 Chapter Summary 3

CHAPTER VI CONCLUSION AND FUTURE WORKS

6.1 Conclusion 12

6.2 Significant Contributions of the Research 12

6.3 Suggestions for Future Work 12

REFERENCES 4

APPENDIXES

x

LIST OF TABLES

Table Number Page

2.1 Summary of technologies 3

3.1 Fault Type Data 4

4.1 Settings of OC relays 4

4.2 The expected relay in various lines 5

5.1 14-bus test system 6

xi

LIST OF FIGURES

Figure Number Page

1.1 Electric power system 1

2.1 Short-circuit current 2

2.2 Network equivalent circuit of Figure ‎2.1 3

2.3 Thevenin equivalent circuit 4

xii

LIST OF ABBREVIATIONS

DG: Distributed Generation

MLPNN : Multi Layer Perceptron Neural Network

RBFNN: Radial Basis Function Neural Network

W: Watt

kW: kiloWatt

MW: Mega Watt

AC: Alternating current

DC: Direct Current

km: Kilometer

kV: Kilo Volt

MVA: Mega Volte Ampere

MSE: Mean Square Error

OC: Overcurrent Relay

xiii

LIST OF SYMBOLS

l: Feeder Length

d: Distance

dtot: Total Feeder Length

Z : Impedance

LZ : Total Line-Impedance

DGZ : The DG Impedance

SZ : The Source Impedance

SU : Voltages of the Main Source

DGU : Voltages of DG Unit

I : Current

SCI : Short Circuit Current

SSCI , : The Grid Contribution of the Short Circuit Current

CHAPTER I

1 INTRODUCTION

1.1 RESEARCH BACKGROUND

In the recent years, the electrical utilities are undergoing rapid restructuring process

worldwide.

In the recent years, the utilities are undergoing rapid restructuring process

worldwide.

1.2 PROBLEM STATEMENT

As a high penetration

1.3 OBJECTIVES OF RESEARCH AND SCOPE OF WORKS

This research focuses on the development of new techniques for

CHAPTER II

2 LITERATURE REVIEW

2.1 DISTRIBUTED GENERATION

Typically, distribution systems

2.1.1 Distributed Generation

Distributed generation can be defined as the generation of electricity by facilities that

are sufficiently smaller than

2.1.2 Effect of Distributed Generation

Defining the mesh currents 1I and 2I and applying the Kirchhoff’s voltage law for

SU and DGU , we get,

2

1.).1().1(

).1(

I

I

ZlZZl

ZlZZ

U

U

LDGL

LLS

DG

S (2.2)

where 1I is the grid contribution of the short circuit current, SSCI ,

, and 2I is

the DG-contribution of the short circuit current, DGSCI ,

, to the total short circuit

current.

2.2 PROTECTION DISTRIBUTION NETWORKS IN THE PRESENCE OF

DISTRIBUTED GENERATION

Conflicts between DG unit and

3

2.2.1 Short Circuit Currents

The fault contribution from a

2.2.2 Power Flow

Radial distribution networks are usually designed for unidirectional

Power flow

2.2.3 Protection

Overcurrent protection schemes for radial distribution systems are designed based on

the available

2.3 DISTRIBUTION SYSTEMS

Electric power systems that are

2.3.1 Review of Methods in Distribution Networks with Distributed Generation

Fault location in a distribution system

2.4 REVIEW OF PROTECTION METHODS

The basis in designing

2.4.1 Distribution System Protection

The purpose of distribution

2.4.2 Review of Protection Coordination Methods

With the presence

4

I. Adaptive Protection Scheme for Distribution Networks

Adaptive protection is a relatively new which is defined as the ability of a protection

system to automatically

Adaptive protection is a relatively new which is defined as the ability of a

protection system to automatically

II. Multi-Agent Protection Scheme for Distribution Networks

An agent is a computer system that is capable of performing autonomous actions in

this environment to meet its design objectives

2.5 CHAPTER SUMMARY

This chapter presents an introduction of

CHAPTER III

3 AUTOMATED FAULT DIAGNOSIS IN A DISTRIBUTION NETWORK

WITH DISTRIBUTED GENERATION

3.1 INTRODUCTION

This chapter describes the proposed

3.2 RADIAL BASIS FUNCTION NEURAL NETWORK

The RBFNN is a feed-forward neural network consisting of three layers, namely, an

input layer

3.3 DISTRIBUTION NETWORK

An important consideration in

3.3.1 Network

Prior to the RBFNN implementation,

Adaptive protection is a relatively new which is defined as the ability of a

protection system to automatically

3.3.2 Classification

The second step is to identify

3.3.3 Location

After identifying the fault type,

6

3.3.4 Determination

After identifying the fault

3.3.5 Restoration

Once the faulty line

3.3.6 Generation

Before executing the fault

3.4 CHAPTER SUMMARY

An automated method have been developed

CHAPTER IV

4 PROTECTION COORDINATION STATEGY IN A DISTRIBUTION

NETWORK WITH DISTRIBUTED GENERATION

4.1 INTRODUCTION

This chapter describes a novel protection

4.2 PROTECTION FUNDAMENTAL

Protective devices are operated to isolate

4.2.1 Main and Backup

Main protection should

4.2.2 Device

The protection coordination study involves the preparation of the one-line diagram of

a power system,

4.3 ALGORITHM

The algorithm which is based on heuristics is an optimal search method satisfied.

4.4 PROPOSED STRATEGY

It is difficult to coordinate the

8

4.4.1 Main Protection Algorithm

After identifying the

4.4.2 Backup Algorithm

In case of misoperation of

4.5 CHAPTER SUMMARY

A new protection coordination strategy in a distribution network with DG units has

been presented by

9

CHAPTER V

5 RESULTS AND DISCUSSION

5.1 RESULTS OF FAULT DIAGNOSIS USING RBFNN

The proposed fault diagnosis method using

5.1.1 Results for the 14 Bus Test System

To verify the performance and accuracy of the proposed

I. Network

Before implementing fault

II. Generation and

The training and testing data

III. Results of Classification

To identify the various fault types

IV. Results of Location

After recognizing the fault type,

V. Results of Isolation

After identifying the fault type

10

VI. Results of Restoration

Once the faulty line and the

5.1.2 Results for the 22 Bus Test System

A 22 bus, 20 kV distribution network with 2 DG units shown in Figure 5.3 is selected

as the test system to verify the performance and accuracy of the proposed

I. Network

The 22 bus test system is divided into three zones as shown in Error! Reference

source not found.. Zones 2 and 3 have one

II. Generation

The training data

III. Results of Diagnosis

Error! Reference source not found. shows the

5.1.3 Results for the 32 Bus Test System

To verify the performance and accuracy of the proposed fault

I. Network

After performing the network zoning procedure,

II. Generation

The training data

III. Diagnosis Results

The fault diagnosis results

63

11

5.1.4 Comparison between RBFNN and MLPNN Results

To further evaluate the effectiveness of

5.2 RESULTS OF STRATEGY

This section presents the results of the proposed

5.2.1 Results of Strategy for the 14 bus test system

To verify the performance and accuracy of the proposed

5.2.2 Results of Strategy for the 22 bus test system

The proposed

5.2.3 Results of Strategy for the 32 bus test system

To verify the performance and accuracy of the proposed

5.3 CHAPTER SUMMARY

In this chapter,

77

CHAPTER VI

6 CONCLUSION AND FUTURE WORKS

6.1 CONCLUSION

In this thesis,

To achieve the first objective of the research which is to the impact of

To address the second objective of the research which is to develop an

automated

The third objective is to develop a new

6.2 SIGNIFICANT CONTRIBUTIONS OF THE RESEARCH

The major contributions of this thesis are summarized as follows:

i. The proposed method

ii. The use

iii. The proposed method

6.3 SUGGESTIONS FOR FUTURE WORK

The proposed techniques for

i. To explore the use of

ii. To implement feature selection

REFERENCES

A Mohamed & M Mazumder 1999. A neural network approach to fault diagnosis in a

distribution system. International Journal of Power & Energy Systems 19 (2):

129-134.

Abdelaziz, A. Y., Talaat, H. E. A., Nosseir, A. I. & Hajjar, A. A. 2002. An adaptive

protection scheme for optimal coordination of overcurrent relays. Electric

Power Systems Research 61(1): 1-9.

Baghzouz, Y. 2005. Voltage Regulation and Overcurrent Protection Issues in

Distribution Feeders with Distributed Generation - A Case Study. 38th Annual

Hawaii International Conference on System Sciences. 66b-66b.

Bretas, A., Moreto, M., Salim, R. & Pires, L. 2006. A novel high impedance fault

location for distribution systems considering distributed generation. IEEE PES

Transmission and Distribution Conference and Exposition, Latin America,

Venezuela. 1-6.

Chaitusaney, S. & Yokoyama, A. 2005. Impact of protection coordination on sizes of

several distributed generation sources. The 7th International Power

Engineering Conference, (IPEC 2005) 669-674 Vol. 662.

Cheung, H., Hamlyn, A., Cungang, Y. & Cheung, R. 2007. Network-based Adaptive

Protection Strategy for Feeders with Distributed Generations. IEEE Canada

Electrical Power Conference (EPC 2007). 514-519.

Doyle, M. T. 2002. Reviewing the impacts of distributed generation on distribution

system protection. Power Engineering Society Summer Meeting, 2002 IEEE.

1: 103-105 vol.101.

El-Zonkoly, A. M. 2011. Fault diagnosis in distribution networks with distributed

generation. Electric Power Systems Research 81(7): 1482-1490.

Fei, W. & Ying, S. 2003. An Improved Matrix Algorithm for Fault Location in

Distribution Network of Power Systems Automation of Electric Power Systems

24(3).

Gaonkar, D. N. 2010. Distributed Generation. Croatia: InTech.

Hui, W., Li, K. K. & Wong, K. P. 2010. An Adaptive Multiagent Approach to

Protection Relay Coordination With Distributed Generators in Industrial

Power Distribution System. IEEE Transactions on Industry Applications

46(5): 2118-2124.

APPENDIX A

RESULT OF FAULT DIAGNOSIS FOR THE 22 AND 32 BUS TEST SYSTEMS

Table A-1 Fault Diagnosis Results of the 22 bus test system

Sample Fault

type

Identify fault location Isolation Restoration

RBFNN 1,3,5,7 RBFNN 2,4,6,8 RBFNN 3, 6, 9, 12 temporary

Distance from

Main

Source(Km)

Distance

from

DG1(Km)

Distance

from

DG2(Km)

Faulty Line

No. CB1 CB2 CB3 CB4

Recloser

‘1’

Close

‘1’

950

meter

of line

1

1 Ph-G 0.960 2.060 7.055 0.98 0 0 0 0 CB1 CB2-CB3-CB4

2 Ph 0.960 2.061 7.059 0.91 0 0 0 0 CB1 CB2-CB3-CB4

2 Ph-G 0.950 2.053 7.060 1.02 0 0 0 0 CB1 CB2-CB3-CB4

3 Ph 0.961 2.057 7.057 1.07 0 0 0 0 CB1 CB2-CB3-CB4

Actual 0.950 2.050 7.050 1 0 0 0 0

200

meter

of line

2

1 Ph-G 1.195 1.794 7.197 1.98 0 0 0 0 CB1 CB2-CB3-CB4

2 Ph 1.189 1.803 7.189 2.03 0 0 0 0 CB1 CB2-CB3-CB4

2 Ph-G 1.211 1.802 7.193 2.01 0 0 0 0 CB1 CB2-CB3-CB4

3 Ph 1.195 1.811 7.190 2.02 0 0 0 0 CB1 CB2-CB3-CB4

Actual 1.200 1.800 7.200 2 0 0 0 0

Continue …

… Continued

350

meter

of line

3

1 Ph-G 2.347 0.643 8.351 3.03 1 0 1 0 CB2 DG1-CB4

2 Ph 2.352 0.657 8.344 3.01 1 0 1 0 CB2 DG1-CB4

2 Ph-G 2.361 0.656 8.346 3.09 1 0 1 0 CB2 DG1-CB4

3 Ph 2.355 0.647 8.351 3.05 1 0 1 0 CB2 DG1-CB4

Actual 2.350 0.650 8.350 3 1 0 1 0

450

meter

of line

4

1 Ph-G 3.450 0.453 9.442 4.01 1 1 1 0 CB4 CB4

2 Ph 3.449 0.458 9.449 3.98 1 1 1 0 CB4 CB4

2 Ph-G 3.450 0.452 9.448 4.00 1 1 1 0 CB4 CB4

3 Ph 3.451 0.456 9.447 4.02 1 1 1 0 CB4 CB4

Actual 3.450 0.450 9.450 4 1 1 1 0

560

meter

of line

5

1 Ph-G 4.560 1.562 10.554 4.96 1 1 1 0 CB4 CB4

2 Ph 4.559 1.555 10.553 4.92 1 1 1 0 CB4 CB4

2 Ph-G 4.560 1.559 10.561 5.02 1 1 1 0 CB4 CB4

3 Ph 4.558 1.556 10.556 5.08 1 1 1 0 CB4 CB4

Actual 4.560 1.560 10.560 5 1 1 1 0

APPENDIX B

MATLAB CODE

clear all; clc;

% determine network % DataNetwork_1; % DataNetwork_2; DataNetwork_3;

% define faulted line Nline_fault = 2;