THE ASSESSMENT OF SWITCHGEAR SYSTEM USING CIRCUIT

BRAKER PROFILER

Ahmad Al-Hakim Bin Shamsudin

Bachelor of Electrical Engineering (Industrial Power)

JUNE 2013

‘I hereby declare that I had read this report entitled “The Assessment of Switchgear System

Using Circuit Breaker Profiler” and found that this project is comply the partial fulfilment for

the purpose of awarding Bachelor in Electrical Engineering (Industrial Power)’

Signature: ………………………………….

Supervisor’s Name: Mr. Azhar Bin Ahmad

Date: 19th June 2013

THE ASSESSMENT OF SWITCHGEAR SYSTEM

USING CIRCUIT BREAKER PROFILER

AHMAD AL-HAKIM BIN SHAMSUDIN

This report is submitted with the

purpose of partial fulfilment the program requirement of awarding

Bachelor of Electrical Engineering (Industrial Power)

Faculty of Electrical Engineering

UNIVERSITY TEKNIKAL MALAYSIA MELAKA

JUNE 2013

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‘I hereby declare that this work in this report is my own except for summaries and

quotation which have been duly acknowledged’

Signature: ………………………………..

Name: Ahmad Al-Hakim bin Shamsudin

Date: 19th June 2013

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Specially for my

Beloved Mom and Dad

And Caring Siblings

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ACKNOWLEDGEMENT

Alhamdulillah, first of all, I would like to express unlimited thankful to my

supervisor, Mr. Azhar Bin Ahmad upon giving me his tremendous opinion and unlimited

ongoing support also his desire to spend his time to guide me in this project throughout my

final year.

Special thanks to my panel judges, Mr. Zul Hasrizal Bin Bohari and Ir. Dr. Rosli

Bin Omar upon his patience and opinion to evaluate my project.

Further, I would like to dedicate my sincere thanks to Technical Expert

(Switchgear) of TNB Research Sdn. Bhd., Ir. Harriezan Bin Ahmad for his willingness and

consultation toward guidance to my project.

I would like also to express my gratitude to Mrs. Anis Niza Binti Ramani, Mrs.

Ainain Nur Binti Hanafi, Mr. Khairul Anwar Bin Ibrahim and Mr. Norhafiz Bin Salim for

their willingness to help when I need it.

Last but not least, I would like to thanks to my dearest parents on their non-stop

caring on my busiest time and also my siblings as well.

Thank You.

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ABSTRACT

The application of circuit breaker in switchgear system is a common method to use

as a protection system. Circuit Breaker Profiler is a circuit to be use to study the trip coil

characteristic of circuit breaker. In this project, it is focused on 33kV Circuit Breaker and

Circuit Breaker Profiler will be use to study several case study based on circuit breaker

mechanism timing test. Based on the test held, the result of the test will be use to build a

trip coil profile signature; this technique known as fingerprinting technique. Timing test

will validate that a circuit breaker of the overall operation within the set limits, but it will

be indicate that monitoring the current flow via the trip coil of the circuit breaker, can

allocate a very dominant tool in analysing the preparedness of a circuit breaker to trip. The

result of the testing specimen of DC current of circuit breaker against time will be

interpreted the average or mean graph of time (millisecond) and DC Current (A) also will

be developed in order to determine appropriate Trip Coil Current Profile. Upon the

completion of this project, appropriate Trip Coil Current Profile and the assessment of

switchgear will be known.

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ABSTRAK

Penggunaan pemutus litar dalam sistem switchgear adalah kaedah yang sama untuk

digunakan sebagai sistem perlindungan. Pemprofil Pemutus Litar adalah satu litar yang

akan digunakan untuk mengkaji ciri-ciri Trip Coil Current Profile. Dalam projek ini, ia

tertumpu kepada 33kV Pemutus Litar dan Circuit Breaker Profiler akan gunakan untuk

mengkaji beberapa kajian kes berdasarkan mekanisme pemutus litar ujian masa.

Berdasarkan ujian yang diadakan, keputusan ujian ini akan digunakan untuk membina Trip

Coil Current Signature; teknik ini dikenali sebagai teknik cap jari. Ujian masa akan

mengesahkan bahawa pemutus litar operasi keseluruhan dalam had yang ditetapkan, tetapi

ia akan menunjukkan bahawa pemantauan aliran arus melalui gegelung perjalanan pemutus

litar, boleh memperuntukkan alat yang sangat dominan dalam menganalisis kesediaan

pemutus litar untuk perjalanan. Hasil spesimen ujian pemutus litar Arus Terus (AT)

terhadap masa akan ditafsirkan purata atau min graf masa (milisaat) dan Arus Terus (A)

akan dibangunkan untuk menentukan Trip Coil Current Profile yang sesuai. Diakhir projek

ini, Trip Coil Current Profile yang sesuai dan penilaian terhadap sistem switchgear akan

diketahui.

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TABLE OF CONTENT

CHAPTER TOPICS PAGE

DECLARATION i

ACKNOWLEDGEMENT iii

ABSTRACT iv

ABSTRAK v

TABLE OF CONTENT vi

LIST OF FIGURE ix

LIST OF TABLE xi

LIST OF ABBREVIATION xii

LIST OF APPENDICES xiii

CHAPTER 1 INTRODUCTION

1.1 Background 1

1.2 Motivation 2

1.3 Problem Statement 2

1.4 Project Objective 3

1.5 Project Scope 3

1.6 Thesis Outline 4

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CHAPTER TOPICS PAGE

CHAPTER 2 LITERATURE REVIEW

2.1 Switchgear System 5

2.1.1 Paschen’s Law 6

2.1.2 Vacuum Interruption Technique 7

2.1.3 Construction of Vacuum Interrupter 8

2.1.4 Operation of Vacuum Interrupter 9

2.1.5 Operation of Circuit Breaker 10

2.1.6 Trip Coil Current Profile 12

2.1.7 Construction of Trip Coil 14

2.1.8 Summary on Switchgear 15

2.2 Condition Monitoring System 16

2.2.1 Introduction of Condition Monitoring System 16

2.2.2 Purposes of Condition Monitoring System 17

2.2.3 Types of Condition Monitoring System 18

2.2.4 Application of Condition Monitoring System

for Circuit Breaker 19

2.2.5 Circuit Breaker Condition Assessment 20

2.2.6 Summary on Condition Monitoring System 21

CHAPTER 3 METHODOLOGY

3.1 Description of Overall Process 22

3.1.1 The Experiment of Trip Coil Profile 23

3.1.2 Data Collection 26

viii

CHAPTER TOPICS PAGE

3.1.3 Data Analysis 27

3.1.4 Full Report Writing 28

CHAPTER 4 RESULT AND ANALYSIS

4.1 The Experiment Result of Switchgear 29

4.2 The Actual Testing of Switchgear 30

4.3 The Mean Graph of Trip Coil Current Profile 31

4.4 The Histogram Graph of DC Current 32

4.5 The Histogram Graph of Time 33

4.6 The Analysis of Opening Time for Circuit Breaker 34

4.7 The Determination of Mean value 35

4.8 The Determination of Difference Value 37

CHAPTER 5 DISCUSSION

5.1 The Mean Average of Trip Coil Current Profile 39

5.2 The Uniformity of the Profiler 41

5.3 The Percentage of Difference Value Analysis 42

5.4 The Application of Circuit Breaker Condition

Assessment in Substation 42

CHAPTER 6 CONCLUSION AND RECOMMENDATIONS

6.1 Conclusion 44

6.2 Recommendation 46

BIBLIOGRAPHY 47

APPENDICES 49

ix

LIST OF FIGURE

FIGURE TITLE PAGE

2.1 Paschen’s Law Graph for several types of gases 6

2.2 Paschen’s Law at low pressure 7

2.3 A section type V801 vacuum interrupter 8

2.4 Basic construction of vacuum interrupter 8

2.5 A vacuum contrate contact 10

2.6 Stages of circuit breaker operation 11

2.7 Illustration of circuit breaker operation 12

2.8 Trip Coil Current Profile 13

2.9 Cross Section of a Common Trip Coil 14

2.10 Condition Monitoring Work Frame 16

3.1 Flow Chart of Methodology’s Summary 23

3.2 DC Supply of Breaker Mechanism and Control Circuit 24

3.3 The un-mounted of 33kV Switchgear 24

3.4 The Kelman Profiler 25

3.5 Raw data obtained from the experiment 25

3.6 The connection of DC Probe 26

3.7 The connection of DC Voltage Probe and AC Current Probe 27

4.1 The result of the experiment at ILSAS 29

4.2 The result of the Actual Testing 30

4.3 The mean average graph of Trip Coil Current Profile 31

4.4 Histogram graph of DC Current 32

x

FIGURE TITLE PAGE

4.5 Histogram graph of Time 33

5.1 A Typical Trip Coil Current Profile 39

5.2 Circuit Breaker Condition Assessment Application 43

xi

LIST OF TABLE

TABLE TITLE PAGE

4.1 The Opening Time for Circuit Breaker 34

4.2 Determination of Mean 35

4.3 Determination of Difference Value 37

5.1 The Summary of the TCCP Section 41

xii

LIST OF ABBREVIATION

ABBREV NAME

DC - Direct Current

emf - electromagnetic force

PMU - Pencawang Masuk Utama

(Transmission Main Intake)

PPU - Pencawang Pembahagian Utama

(Main Distribution Substation)

SSU - Stesen Suis Utama

(Main Switching Station)

ILSAS - TNB Integrated Learning Solution

A - Ampere

ms - Millisecond

V - Volts

LRT - Light Rail Transit

MSG - Malaysian Sheet Glass Sdn. Bhd.

TCCP - Trip Coil Current Profile

xiii

LIST OF APPENDICES

NUM TITLE PAGE

Appendix A Flow Chart for Final Year Project I & II I

Appendix B Gantt Chart FYP II

Appendix C Technical Data for 33kV TAMCO Switchgear III

Appendix D Experiment Result at ILSAS IV

Appendix E Actual Testing for Trip Coil Current Profile around

Kuala Lumpur and Selangor Area V

Appendix F Turn-It-In Plagiarism Report VI

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CHAPTER 1

INTRODUCTION

1.1 Background

In power system, the equipment and devices always are evolving

throughout time. The evolving process makes the needs of the maintenance program

have been shove over and over again. There are other methods that can be use in

assessing switchgear. According to Steward (2008), switchgear is a common term

covering switching device and their combination with associated protection,

measuring, and control and regulating equipment. The basic components of

switchgear are load-side conductor and supply-side conductor, insulation from earth

to sustain the conductor, a moving contact structured to be joined or separate and a

driving mechanism and its buckled drive linkage to the moving contact.

One of the most important components in switchgear is the earthing

facilities. In order to permit safe working state on the unit associated cable or busbar,

the functionality of the circuit breaker rightly include a mean of earthing. Circuit

breaker in switchgear is interruption techniques that use in power system fields. In

order to remove traditional approach, an alternative approach to assure the reliability

of the switchgear or including of whole plant. So, the method to propose is using

Circuit Breaker Profiler.

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1.2 Motivation

This project will become as a milestone in order to apply the condition monitoring

in this country. This project is conducted due to the lack of expertise; as in power system,

the manufacturing factories usually use large number of manufacturing process, operation

and maintenance. So the engineer need continuously update and sublime their expertise. If

the engineer is lack of expertise the hidden problem always is a hidden problem.

It is also due to no effective systems that respond to abnormalities rapidly, the

prolonged absence of a system with quick respond make it difficult for hidden problem to

become seen. So, this is one of the systems that will help to improve the existing system.

1.3 Problem Statement

Maintenance plan programme is time consuming and shortage of resources

if the methods use is traditional approach. Condition monitoring technique of the trip

coil profiling was developed where fingerprinting was used to emphasize any

anomalies in the performance of circuit breaker.

Although fingerprinting shows diversion from the custom, it did not

manifest with sufficient detail of the sources of the problem. As every type of the

circuit breaker has a characteristic profile, deterioration in the circuit breaker enable

to trip are indicated as unique changes of that profile. It was a proposition, that if a

thorough understanding of circuit breaker of tripping mechanism was attained, the

profile shall provide an assessment of its preparedness to trip.

Circuit Breaker Condition Assessment is a one way of knowing the

fundamental that causing the abnormalities on circuit breaker operation delay. By

investigating the characteristic of the Trip Coil Current Profile, it can be known that

the flaws that implicated to the circuit breaker due to idling for a long time without

tripping.

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1.4 Project Objective

This project is primarily about the studies of Circuit Breaker Condition Assessment

of 33kV switchgear in several substations in Malaysia throughout investigation and

analysis based on Circuit Breaker Condition Assessment. This project aims to:

Investigate the development of trip coil profile on a circuit breaker using

profiler.

Assess a circuit breaker based on it reaction to trip if faulted condition

occurred.

Determine the deterioration of operation of switchgear based on condition

monitoring.

1.5 Project Scope

The analysis of this project will be conducted using MATLAB software.

This project only concentrated on 33kV switchgear. The experiment of testing the

specimen will use the on 33kV TAMCO Switchgear at TNB Integrated Learning

Solution Institution (ILSAS), Kajang Selangor. Beside, the experiment conducted

will be use as a reference of actual test specimen of several 33kV switchgears in

Kuala Lumpur and Selangor area. The overall analysis will be accordingly to TNB

Research standard for developing the trip coil profile of switchgear.

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1.6 Thesis Outline

In chapter 1, the background of this project was included. The problem

statement, the objectives and the scope of project is also discussed. This part is to

show the limitation of the project.

Chapter 2 will treated about literature review. Literature review is an

aggregation of studies that has been done by other researchers that have the

resemblance with the field of the project. This literature review can be used as

guideline in order to finish up the project. It is essential to have literature review so

that the project will not diverge from the project scope.

Chapter 3 is outlining about the methodology of this project. In this chapter,

it will explain on the methods system that is used for this project including all

substantial modules of the system. It also discusses on software and analysis that will

be used in the project.

Chapter 4 is about the analysis and discussion. In this chapter, it will be

discusses all about the design system of the project. It starts with explanation on how

the ideas will be applied, how to choose and apply the programming that control the

system and also include the project analysis.

Last but not least, Chapter 5 which is conclusion and recommendation. In

this chapter will be include the summary of the project where it will conclude overall

of the project and recommendation for the future development.

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CHAPTER 2

LITERATURE REVIEW

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This chapter will review on Switchgear System and Condition Monitoring.

The switchgear is manufactured by TAMCO Switchgear (Malaysia) Sdn. Bhd. The 33kV

switchgear is using vacuum impregnate for its filler.

2.1 Switchgear System

In this project, the switchgear of 33kV is the main focus of the study. In

summary, most of 33kV switchgear systems in Malaysia are using vacuum interruption

techniques. This switchgear type is VH3; the circuit breaker type is VY-3OM25D. The

normal current of the switchgear is 1250A. The highest voltage this switchgear can

withstand is 36 kV. This switchgear is having earthing device of Rated Short Circuit

Current of 79kA. This switchgear using vacuum interrupter that manufactured by EATON

and the number break per pole is Single Break per Pole. Single Break per Pole can be

defines as a fixed contact portion and a movable contact portion. This type of break has to

carry the whole of the breaking current. The length of each break is 23mm. The material of

current carrying conductor is copper. The opening time of the main contact is 25ms. For

further information, the full technical data can be refers to Appendix C.

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2.1.1 Paschen’s Law

The relationship between voltage resistance and electrode spacing is accordingly to

Paschen’s Law. Paschen's Law states that the breakdown voltage is the function of pressure

(Torr) times by distance of gap (centimeter) [VBreakdown =f (P x d)]. Figure 2.1 show that

Paschen’s Law of helium gas, neon gas, argon gas, hydrogen gas and nitrogen gas. Based

on the Paschen’s Law, these recommend that the voltage resistance of a gap between

electrodes is proportional to both the electrode spacing and the pressure of the gas

(Stewart, 2004).

It is providential that this law only applies and true within finite limits, differently

vacuum switchgear could not exist. Air pressure is reduced when starting at atmospheric

pressure; the voltage resistance also reduces, satisfying Paschen’s Law. Nevertheless, at

very low pressure, a tremendous change is takes place. Boost decrement in pressure will

result in the increment of resistance voltage. This can be graphically explained by Figure

2.2 (Naidu & Kamaraju, 2009).

Figure 2.1: Paschen’s Law graph for several types of gases (Naidu & Kamaraju, 2009)

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Figure 2.2: Paschen’s Law at low pressure (Stewart, 2004)

On the other hand, at very low pressure, the distortions from the Paschen’s Law are

observed when the breakdown mechanism is not affected by the characteristics of the gas

but it is reckon on the purity and the property of the electrodes (Naidu & Kamaraju, 2009).

2.1.2 Vacuum Interruption Technique

In early of 1970s, first introduction and commercialization of vacuum interrupter is

being made. The vigorous development and tremendous reduced size of vacuum

interrupter makes the increment size of short-circuit rating. An arc needs metal vapour

from the metal contacts to prolong itself and it cannot exist in a vacuum, ideally until a

natural current zero is attained. At this specified point, the metal vapour should distil back

toward the contact, refusing conductivity so that current lay off to flow. In contrast, the

contact materials are all essential to the interruption process. Besides, the material utilized

for the contacts must have the compensate characteristics for the conduction of normal

current and they must minify the natural tendency of metal to cold unify when urged

together under high-vacuum condition. In advance, they must not liberate gas when

interrupting current; as this would detonate the high-vacuum essential for the entire process

to be repeated much time over throughout the life of the vacuum interrupter. Figure 2.3

shows an example of vacuum interrupter (Stewart, 2004).

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Figure 2.3: A sectioned type V801 vacuum interrupter (courtesy of ALSTOM T&D Ltd)

It follows as the voltage will be imprint crosswise an interrupter comply current

interruption, insulating materials have to be considered in the design of the vacuum

interrupter envelope. These insulating materials must be isolated from condensing metal

vapour from the contacts which would differently deteriorate their insulating

characteristics (Stewart, 2004).

2.1.3 Construction of Vacuum Interrupter

In vacuum interrupter, the protection from the internal surface of isolating

envelopes is prepared by three metal shields, known as spatter shields or arching shields. It

is brazed to the centre band and end caps of the interrupter. A substitute method of

protecting the isolating envelope is to have both of the fixed and moving contact set up to

have their contact faces placed within the central canister. Figure 2.4 showing a basic

construction of vacuum interrupter (Stewart, 2004).

Figure 2.4: Basic construction of vacuum interrupter (Stewart, 2004)