STUDY OF BEHAVIOR OF SURGE ARRESTER UNDER LIGHTNING...
Transcript of STUDY OF BEHAVIOR OF SURGE ARRESTER UNDER LIGHTNING...
STUDY OF BEHAVIOR OF SURGE ARRESTER UNDER LIGHTNING STRIKE
DZULHAIDI BIN ALI
A project report submitted in partial
fulfillment of the requirement for the award of the
Degree of Master of Electrical Engineering
Faculty of Electrical and Electronics Engineering
Universiti Tun Hussein Onn Malaysia
JULY 2015
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ABSTRACT
Surge arrester is one of the important component in the electrical system network either
it is in a low voltage system or high voltage system. The purpose of surge arrester is
generally to limit or suppress the overvoltage due to lightning phenomena or switching
activities of in network. In this project, the design of model surge arrester and we
simulate it using computer software named Alternative Transient Program (ATP) is most
popular to study the transient time. By using this software, the behavior of surge arrester
during the lightning can be identified and this behavior can be seen from this simulation.
Two types of different metal oxide varistor (MOV) used in constructing this surge
arrester for simulation. Each of type will be execute in two models of surge arresters
which named by IEEE Model and Pincetti-Gianettoni Model. With three-tier device
voltage of 50 kV, 100 kV and 200 kV with the setting 1.2 / 50 μs were injected to
determine and study the output of the surge arrester. From the finding of this project the
output voltage value is too small compared to the one injected where for IEEE model is
only 1% and Pincetti-Gianettoni Model is 11%.
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ABSTRAK
Peranti penangkap kilat ialah komponen paling penting dalam rangkaian sistem elektrik
sama ada sistem voltan rendah atau sistem voltan tinggi. Tujuan peranti penangkap kilat
ini biasanya adalah untuk menghadkan atau memintas voltan lebih yang disebabkan
oleh fenomena kilat atau aktiviti pengsuisan rangkaian. Tujuan projek ini adalah untuk
mereka bentuk model peranti penangkap kilat dan simulasi model ini akan
menggunakan perisian komputer yang dinamakan sebagai Program Transient Alternatif
(ATP) suatu perisian yang sangat popular digunakan untuk mengkaji pada waktu fana.
Melalui perisian ini, perbezaan kelakuan peranti penangkap kilat sewaktu kilat boleh
dikenalpasti dan kelakuan peranti ini dilihat daripada hasil simulasi tersebut. Terdapat
dua jenis perbezaan oksida logam rintangan boleh ubah (MOV) yang digunakan
didalam pembinaan peranti penangkap kilat tersebut dipilih untuk simulasi. Setiap jenis
MOV akan digunakan didalam dua model peranti penangkap kilat yang dinamakan
sebagai Model IEEE dan Model Pinceti- Gianettoni. Setiap litar model ini menggunakan
tiga peringkat voltan iaitu 50 kV, 100 kV dan 200 kV dengan tetapan 1.2/50 µs yang
disuntik untuk menentukan dan mengkaji keluaran daripada peranti penangkap kilat ini.
Penemuan di akhir projek ini untuk setiap litar model tersebut, nilai voltan keluaran
adalah terlalu kecil berbanding dengan nilai masukkan dimana untuk Model IEEE hanya
1% dan Model Pinceti-Gianettoni sebanyak 11%.
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CONTENTS
TITLE i
DECLARATION ii
DEDICATION iv
ACKNOWLEDGEMENT v
ABSTRACT
ABSTRAK
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CONTENTS viii
LIST OF TABLES xi
LIST OF FIGURES xii
LIST OF SYMBOLS AND ABBREVIATIONS xiv
CHAPTER 1
INTRODUCTION
1.1 Project Overview 1
1.2 Objectives of Project 2
1.3 Scopes of Project 2
1.4
1.5
1.6
Problem Statement
Organization of Report
Conclusion
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3
4
CHAPTER 2 SURGE ARRESTER CHARACTERISTICS: A
REVIEW
2.1 History of Arrester Technology
2.1.1 Simple Rod Gap
2.1.2 Electrolytic Arrester
2.1.3 Oxide Film Arrester
2.1.4 Gapped Silicon Carbide Surge Arrester
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2.2 Metal Oxide Surge Arrester
2.2.1 IEEE Model of Surge Arrester
2.2.2 The Pinceti-Gianettoni Model Surge
Arrester
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2.3 Lightning on Overview 16
2.4 Model Mathematics for Surge Arrester 18
2.5 Model Construction for Surge Arrester 18
CHAPTER 3 ATP SURGE ARRESTER MODEL FOR
SIMULATION
3.1 Introduction 21
3.2
3.3
Flow Chart of Project
3.2.1 Preparation Model of Surge Arrester in
ATP Software
3.2.1.1 IEEE Model Circuit in ATP Software
3.2.1.2 Pinceti-Gianettoni Model Circuit in ATP
Software
3.2.2 Calculation of Parameter in the IEEE Model
of Surge Arrester
3.2.3 Calculation of Parameter in the Pinceti-
Gianettoni Model of Surge Arrester
3.2.4 Setting of Lightning Impulse Waveform
3.2.5 V-I Characteristic Curve for MOV
3.2.6 Simulation of the Modeling Circuit
Conclusion
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CHAPTER 4 RESULT, ANALYSIS AND DISCUSSION
4.1 Introduction 34
4.2 Output from Simulation Model
4.2.1 IEEE Model for MOV Type 1
4.2.2 IEEE Model for MOV Type 2
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x
4.2.3 Pinceti-Gianettoni Model for MOV Type 1
4.2.4 Pinceti-Gianettoni for MOV Type 2
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4.3 Comparisons between IEEE Model and Pinceti-
Gianettoni Model
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4.4 Conclusion
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CHAPTER 5 CONCLUSION AND RECOMMENDATION
5.1 Introduction 47
5.2 Conclusion 47
5.3 Recommendation
48
REFERENCES 49
VITA 51
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LIST OF TABLES
3.1 The characteristic of MOV for Type 1 28
3.2 The characteristic of MOV for Type 2 30
4.1 Summary of all simulation for Type 1 and Type 2
MOV
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LIST OF FIGURES
2.1 Early power system lightning arrester 6
2.2 Horned Gapped Arrester 7
2.3 Electrolytic Arrester 8
2.4 Pellet Type Oxide Film Arrester 1915 9
2.5 First Silicon Carbide Surge Arrester 10
2.6 Schematic representation of the magnitude of
voltages and overvoltage versus duration of their
appearance.
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2.7 IEEE Model of surge arrester 13
2.8 Non-linear characteristic for A0 and A1. The
voltage is in p.u. referred to the Ur8/20
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2.9 Pinceti-Gianettoni Model for surge arrester 14
2.10 Diagram showing lightning strike 16
2.11 Standard waveform for lightning 17
2.12 Construction of Surge Arrester for Porcelain
Housing
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3.1 Flow chart of Project 22
3.2 The blocks diagram for modeling circuit in ATP 23
3.3 IEEE Model circuit draw in ATP software 23
3.4 Pinceti-Gianettoni Model circuit draw in ATP
software
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3.5 Circuit to identify the Lightning Impulse Waveform 25
3.6 Standard Lightning Waveform with 50 kV peak
value
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3.7 Type 1 of MOV for V10 125 kV 29
3.8 Type 2 of MOV for V10 248 kV 30
3.9 The complete IEEE model circuit in ATP software 31
3.10 The complete Pinceti-Gianettoni Model in ATP
software
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4.1 Output Waveform for peak of Input is 50 kV 34
4.2 Output waveform for peak of Input is 100 kV 34
4.3 Output waveform for peak of Input is 200 kV 35
4.4 Output waveform for peak of Input is 50 kV 36
4.5 Output waveform for peak of Input is 100 kV 37
4.6 Output waveform for peak of Input is 200 kV 38
4.7 Output waveform for peak of Input is 50 kV 38
4.8 Output waveform for peak of Input is 100 kV 39
4.9 Output waveform for peak of Input is 200 kV 40
4.10 Output waveform for peak of Input is 50 kV 41
4.11 Output waveform for peak of Input is 100 kV 42
4.12 Output waveform for peak of Input is 200 kV 42
4.13 The differences of type of MOV 44
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LIST OF SYMBOLS AND ABBREVIATIONS
A - Ampere
kA - Kilo Ampere
V - Volt
kV - Kilo Volt
Vm - Maximum Voltage
Vr - Rated Voltage
Vn - Normal Voltage
F - Frequency
𝝮 - Ohm
M 𝝮 - Mega Ohm
µs - Micro Second
ms - Mili Second
µH - Micro Henry
pF - Pico Farad
p.u. - Per Unit
m - Meter
U - Voltage
I - Current
R - Resistor
L - Inductance
C - Capacitor
T - Time
Tsta - Time Start
Tsto - Time Stop
m² - Meter Square
A - Area
CHAPTER 1
INTRODUCTION
1.1 Project Overview
In recent years, using metal oxide (ZnO) arresters is a common and prevalent affair for
transformers, capacitance banks etc protection against impulse of overvoltage.
Therefore, correct and accurate investigation of ZnO arresters behavior in power
networks requires correct simulation for the existing transient state software. Several
papers have been presented under arresters modeling title [3, 4, 5, and 6] each has
concerned different parameters in simulation process.
At the beginning, the arrester was just modeled by a nonlinear resistance due to
the nonlinear feature of the varistor tablets. The leakage capacitances stand around the
arrester were then under consider in transient state simulations due to high frequency
bands (spectrums) existence. This was specially confirmed according to the crystal
shaped structure of varistors. In investigations accomplished between the waveforms
resulted by voltage residual and the arresters discharge current, a series inductance was
added to the arrester model due to a short delay exists in current peak and the voltage
peak waveforms. Some other models were reported by Daniel (1985) and then with
IEEE workgroup (1992) because the mentioned inductance was just properly performing
in a limited range of frequencies. The IEEE model was an appropriate model from
quality and quantity view point but was sensibly losing its efficiency and was creating
difficulties in modeling process due not existence of voltage switching information in
majority of catalogs (according to difficulty of such test). Therefore, other models were
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presented to overcome such problem inspired by this model (Kim at el., 1996; Pinceti
and Giannettoni, 1999).
In this study, the residual voltage of the arrester of qualitative and quantitative
aspects is under consider as well as the discharged energy value, unlike other papers just
have investigated the maximum value of impulse caused residual voltage.
1.2 Objectives of this project
a) To design surge arrester model using Alternative Transient Program,
ATP.
b) To study the behavior of surge arrester when lightning strike.
c) To compare the output voltage between IEEE Model and Pinceti-
Gianettoni Model.
1.3 Scopes of this project
a) Simulation only under lightning condition using Alternative Transient
Program, ATP.
b) Simulation only with using two type of metal oxide varistor.
1.3 Problem Statement
Lightning is the most frequent cause of overvoltage on distribution systems. Basically,
lightning is a gigantic spark resulting from the development of millions of volts between
clouds or between a cloud and the earth. It is similar to the dielectric breakdown of a
huge capacitor. The voltage of a lightning stroke may start at hundreds of millions of
volts between the cloud and earth. Although these values do not reach the earth, millions
of volts can be delivered to the buildings, trees or distribution lines struck. In the case of
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overhead distribution lines, it is not necessary that a stroke contact the line to produce
overvoltage dangerous to equipment. This is so because "induced voltages" caused by
the collapse of the electrostatic field with a nearby stroke may reach values as high as
300 kV.
Surge arrester is the one way to resolve overvoltage due to the lightning strike.
This because the special characteristic material used in the surge arrester called metal
oxide surge arrester (MOSA).
1.5 Organization of Report
This report is divided into five main chapters which will explain the structure of the
project. Brief description of each chapter as follows:
Chapter 1: This chapter explains the general introduction of the metal oxide (ZnO) used
as a surge arrester and the research has been previously done. This chapter also includes
the objectives, scopes, and problem statement of this project.
Chapter 2: Chapter two entitle literature review gives minutely explanations of the
history, types of surge arrester and modelling circuit of surge arrester. Actually
nowadays studying in surge arrester is easier with due to modelling circuits and many
infrastructures that are available.
Chapter 3: In this chapter, is the explanation the method for constructing this project.
For simulation, this project is using of the Alternative Transients Program (ATP) where
this software is most familiar in transient power analysis.
Chapter 4: This chapter includes the results of the simulation and the discussions. It
will discuss of result from the simulation, comparison between the model and the
relative error of each model.
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Chapter 5: This is the closing chapter of this project. In this chapter, it will cover the
conclusion and recommendations that has been stated. From this recommendation, it can
be use for the further studies on the surge arrester.
1.6 Conclusion
In this chapter, is more explained initial of introduction of this project and structure of
this project. Objective and scope of this project also mention in this chapter to explain
the purpose and direction of project. Also the organization of project is covered in this
chapter to give overview of project.
CHAPTER 2
SURGE ARRESTER CHARACTERISTICS: A REVIEW
2.1 History of Arrester Technology
The earliest roots of lightning protection of power systems dates back to the middle of
the 18th century from 1890 to 1930 will be covered in this part of the history of
lightning protection of power systems. During this era, lightning protection of electrical
equipment divides into many subcategories, such as communications, electronics, radio
towers, railroad (DC), and the one discussed herein, power systems. Protection of the
telegraph gave birth to the gapped device first called an arrester. It wasn’t until the
1890’s that power lines were added to the utility poles crisscrossing the country and
immediately needed arresters that could protect them from lightning also. The
fundamental difference however is that telegraph lines were not energized 100% of the
time as are power lines and the designs of the pre 1890 arrester used to protect the
telegraph lines just did not meet the needs of power systems.
2.1.1 Simple Rod Gap
Power system engineers interested in lightning protection soon learned that the gap,
what was sufficient for telegraph protection, was not of sufficient separation distance to
interrupt the current from the 60 Hz power arc after the lightning surge was over. This
current flowing off the power system from the AC source became known as power
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follow current and it remained a significant challenge to the arrester designers for this
entire era. They quickly learned that the only way to interrupt this power follow current
once it flashed over was to turn off the AC power or insert a resistance into the circuit.
The early means of inserting resistance in series with the gap was to change the size of
the gap. In Figure 2.1, the arrester inventor, Sperry, ran the ground lead of the arrester
through a magnetic solenoid. If the gap sparked over from lightning and was followed
by power system current, it would pulse the solenoid, which in turn would allow the gap
to snap open. The added distance in the gap increased the length of the arc, which is a
common means of increasing the arc resistance. This increase in resistance resulted in
interruption of the arc when the voltage crossed zero. It would appear that the Sperry
arrester would be a maintenance issue in that it needed to be reset after a strike:
something more was needed.
Figure 2.1: Early power system lightning arrester [7]
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The second method of increasing the series resistance of the gap was to use a
linear resistor; however, as the system voltages increased this also became a problem.
A third design that can still be seen protecting insulators today was the Horned Gapped
Arrester. Figure 2.2 shows an 1896 version of this arrester type. The principal behind
this type of arrester is that as the arc burns, the magnetic field pushes the arc out toward
the ends of the electrodes. Since the gap size increases from the bottom to the top, the
length of the arc increases, which in turn increases its resistance. This action limits the
current to levels that can lead to extinguishment at voltage zero.
Figure 2.2: Horned Gapped Arrester [7]
2.1.2 Electrolytic Arrester
In 1908 the new arrester type called electrolytic arrester was introduced and was the first
design to use a nonlinear current-limiting resistance element to limit follow current and
allow arc interruption. The design of electrolytic arrester consisted of a sphere gap in
series with a tank containing aluminum electrodes separated by a liquid electrolyte as
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per Figure 2.3. The aluminum electrodes were formed into cells by electrolytic ally
depositing a non conducting film of aluminum hydroxide thick enough to withstand the
applied voltage.
A lightning surge would momentarily puncture the non conducting aluminum
hydroxide film. However, the follow current from the system caused the punctured hole
to heal itself by the same electrolytic mechanism used to initially coat the aluminum
electrodes. The main disadvantage of the electrolytic arrester was the electrolyte itself
caused deterioration of the film. The electrolytic arrester, therefore, had to be recharged
daily by connecting it to the power system.
For the higher voltage systems, the chemical arrester, as it was known, had the
answer to the series resistance issue. Arrester designers had learned that the perfect
arrester would have a resistance in series with the gap that had non-linear characteristics.
This means that at higher voltages and currents it would have lower resistance. This
variable resistance made it possible for the arrester to conduct high lightning currents,
and after the event it was also able to assist the gap to interrupt the follow current.
Figure 2.3: Electrolytic Arrester [7]
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2.1.3 Oxide Film Arrester
Figure 2.4: Pellet Type Oxide Film Arrester 1915 [7]
This new pellet type arrester had the excellent voltage and current characteristics of the
aluminum cell arrester and then without a liquid dielectric as per shown in Figure 2.4.
Also in this arrester had an additional advantage of lower cost and was better suited for
line protection proportionate to electrolytic arrester. However, this type of arrester has
some weakness such as it have a limited lifetime due to damage to the oxide film during
each surge. This damage was not repairable as in the liquid oxide film arrester and it
clearly more work was needed in the industry.
2.1.4 Gapped Silicon Carbide Surge Arrester
In 1926 John Robert Mc Farlin, who was still working for ESSCO, filed for a patent
using a new material that he referred to as: “infusible refractory materials of limited
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conductivity and comparatively low specific resistance in the silicon carbide family.” He
goes on to state that “these properties greatly enhance the effectiveness, durability,
stability and simplicity of surge arresters.” Thus began the long history of the Silicon
Carbide (SiC) family of arresters shown in Figure 2.5. This type of arrester remained in
production into the 1990’s in the US and is still in production in other parts of the world.
As design engineering manager of the surge arrester business at Cooper Power Systems;
this author personally shut down the last US based production line of this product in
1994.
Figure 2.5: First Silicon Carbide Surge Arrester [7]
It seems surprising that the introduction of the first SiC arrester did not come
from GE or Westinghouse, the titans as they were in the area of overvoltage protection.
Silicon carbide resistance material quickly earned the number one position in arrester
designs for all voltage levels.
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2.2 Metal Oxide Surge Arrester
Metal oxide surge arresters (MOSA) are widely used as protective devices against
switching and lightning pulse overvoltage occur in electrical power system. Nowadays,
several types of surge arresters are available such as gapped silicon carbide, gapped or
non gapped metal oxide. All type of surge arrester is operating at similar manner which
mean surge arrester is high impedances at normal operating voltages and become low
impedances when surge conditions. An ideal arrester must conduct electric current at a
certain voltage above rated voltage, hold the voltage with little change for the duration
of overvoltage and substantially cease conduction at very nearly the same voltage at
which conduction started. In the other word, surge arrester constitutes an indispensable
aid to insulation coordination in the power electrical systems.
Figure 2.6 explained the magnitude of voltages and overvoltage in the electrical
power system. Where the X axis (time) is divided into several section for fast-front
overvoltage cause by lightning, in microsecond range, slow-front overvoltage by
switching in millisecond range then temporary overvoltage and highest system voltage.
The overvoltage can possible reached over the withstand voltage of equipment insulation
especially for lightning overvoltage then the equipment insulation cannot withstand the
occurring dielectric stresses.
Even though a great number of surge arrester, which are gapped arrester with
made from silicon carbide (SiC) are still in use but for new installation almost is using
metal oxide without gaps, which means arresters with resistors made from metal oxide.
If surge current in the kilo ampere range are injected into the arrester, such as in case
when lightning or switching overvoltage occur, then the voltage across its terminal will
remain low to protect the insulation from the effect of overvoltage.
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Figure 2.6: Schematic representation of the magnitude of voltages and
overvolatages versus duration of their appearance. [8]
The non linear characteristic (V-I characteristic) of MOSA is the important factor
why it is selected in the surge arrester construction. The physical construction of metal
oxide surge arresters consists of metal oxide disc inside a porcelain or polymer insulator.
By adding the metal oxide disc in series mean the voltages value is also increased. For
the higher energy ratings can be achieved with using larger diameter of metal oxide disc
or parallel columns of disc.
2.2.1 IEEE Model of Surge Arrester
The IEEE Model was recommended by IEEE W.G.3.4.11 as shown in Figure 2.7 [1]. In
this model two of non linear resistor called A0 and A1 and it is separated with RL low
pass filter. For arrester discharge currents with slow rising time, the influence of the
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filter is negligible thus A0 and A1 are essentially in parallel and characterize the static
behavior of the MOSA.
Figure 2.7: IEEE model of surge arrester [1]
For the fast rising surge current, the impedance of the filter become more
significant, indeed the inductance L1 derives more current into the non-linear branch
A0. Since A0 has a higher voltage for a given current than A1, the model generates a
higher voltage between input terminals, what matches the dynamic characteristics of
MOSA.
A0 and A1 can be derived by the curve as per Figure 2.8. The per-unit (p.u.) is
referred to the peak value of the residual voltage measured during a discharge test with
10kA lightning current impulse (Ur8/20). This curve is to adjust to get a good fit with the
published residual voltages for switching surge discharge currents.
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Figure 2.8: Non-linear characteristic for A0 and A1. The voltage is in p.u. referred to the
Ur8/20 [9]
The inductance L0 represents the inductance associated with the magnetic fields
in the immediate vicinity of the arrester. The resistor R0 is used to avoid the numerical
oscillations when running the model with a digital program. While the capacitor C0
represents the external capacitance associated to the height of the arrester. The values of
C0, L0, R0, L1 and R1 can be determined by follow a given formulas (1) to (5) and all the
components is related to the physical dimensions of the arrester. [1]
(2.1)
(2.2)
(2.3)
(2.4)
(2.5)
d is the estimate high of the arrester in meter
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n is the number of parallel columns of MO in the arrester
The component of L1 is the most influence on the result of the arrester analysis.
However the initial value of L1 is given by the physical dimensions of the surge arrester,
it should be to be adjusted with try and error procedure to match the residual voltages for
lightning discharge currents published in the manufacturer’s catalogue.
2.2.2 The Pinceti-Gianettoni Model Surge Arrester
Figure 2.9: Pinceti-Gianettoni Model for surge arrester [2]
From Figure 2.9, is proposed the Pinceti-Gianettoni Model for surge arrester [2].
Actually this model is based on the IEEE Model but with some modification of
eliminated the capacitance, C. This capacitance is eliminated so the effects on behavior
model can be negligible. This capacitance is replaced by high resistance (about 1M𝝮) at
the input terminal and the function of this resistor only to avoid the numerical troubles.
The operating principle is quite similar to that of IEEE Model surge arrester.
Where the entire component is this model can be calculated following this
equation: [2]
(2.6)
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(2.7)
Uris the rated voltage.
Ur1/T2 is the residual voltage at 10kA fast front current surge (1/T2µs). The decrease time
is not explicitly written because different manufactures may use different values. This
fact does not cause any trouble, since the peak value of the residual voltage appears on
the rising front of the impulse.
Ur8/T2 is the residual voltage at 10kA current surge with 8/20 µs shape.
R0 is 1M𝝮 is introduced to avoid numerical instabilities.
Refer to formula (6) and (7), this Pinceti-Gianettoni Model is not depending on
physical dimensions and it only depend on electrical data by given from manufacturers.
2.3 Lightning on Overview
Lightning is a physical phenomenon that occurs when the clouds acquire charge or
become polarized, so that the electric fields of considerable strength are created within
the cloud and between the cloud and adjacent masses such as earth and other clouds,
[12]. When these fields become excessive, to the extent that the dielectric (the air) of
intervening space can no longer support the electrical stress, a breakdown or lightning
flash occurs; this is usually a high-current discharge. This situation can be depicted in
Figure 2.10.
Also lightning is the main reason for outages in transmission and distribution
lines [12]. The lightning problem is classified as a transient event. When lightning
strikes a power line, it is like closing a “big switch” between a large current source and
the power line circuit. The sudden closing of this “big switch” causes an abrupt change
in the circuit conditions, creating a transient. There is also the case when the lightning
strikes the vicinity of the power line and the large magnetic field generated from the
lightning current cause mutual coupling between the power line and the lightning. The
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event alters the conditions of the power line circuit, as a result, produce an electrical
transient. The lightning waveform can be defined in Figure 2.11.
Figure 2.10: Diagram showing lightning strike [12]
Figure 2.11: Standard waveform for lightning [12]
The study of lightning strokes in power lines is very important because it is
known that lightning does strike the same structure over and again. This can be a very
serious problem for power lines, typically, the highest structures located in high
incidence lightning regions [14]. Any structure, no matter its size, may be struck by
lightning, but the probability of a structure been struck increases with its height. Very
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close dart leaders can make as significant a contribution as return strokes in inducing
voltages and currents on power systems [9].
2.4 Model Mathematics for Surge Arrester
The V-I characteristic of a surge arrester has several exponential segments, where each
segment can be approximated by
(2.8)
Where q is the exponent, q is the multiplier for the segment and Vref is the arbitrary
reference voltage that normalizes the equation and prevents numerical overflow during
exponentiation.
The first segment can be approximated by a linear relationship to avoid
numerical underflow and speed the simulation. At this first segment the resistance is
should be very high since the surge arrester should have a little effect on the steady-state
solution of the network. At normal steady-state operation currents of surge arrester
should be less than 0.1 A. At the second segment is defined by the parameters p, q and
Vmin, which is the minimum voltage for segment. The accuracy of the surge arrester
model can be enhance with multiple segment are typically used since the exponent
decreases as the current level increases.
2. Model Construction for Surge Arrester
Before construct model of surge arrester, the some data must be obtained from the
manufacturer of surge arrester. The data is:
a) Manufacturer’s rating and characteristic
b) Manufacturer’s V versus I curve
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At the factory, the manufacturer is tested all single disc of metal oxide with a
current pulse and record their reference voltage. A typical test pulse current has a peak
10 kA with an 8/20 µs waveform has been used during their testing. The peak voltage
from result testing of this typical pulse current is called reference voltage V10, the
voltage at 10 kA for a single column of surge arrester. The V-I characteristic curve of
metal oxide curve is often use the value of V10 as the 1 per-unit (p.u.) value. The voltage
from V-I characteristic curve can be determine with multiply the p.u. metal oxide by the
V10 for that rating.
The selection of reference voltage proportional to the arrester rating V10, number
of parallel columns of discs and voltage versus current (V-I) characteristic in p.u. of the
reference voltage is the next step. Surge arrester V-I characteristic choose is depends
upon the type of transient being simulated since current waveform with faster rise times
will result in higher peak voltages. Manufacturer of surge arrester often publish several
curves such as:
a) The 8/20 µs characteristic applies for typical lightning surge simulations.
b) The front wave (FOW) characteristic applies for transients with current.
c) The 36/90 µs characteristic applies to switching surge simulations.
d) The 1 ms characteristic applies to low frequency phenomena.
For each test waveform, manufacturers may supply minimum and maximum
curves. The maximum curve is generally used since it results in the highest overvoltage
and the most conservative equipment insulation requirements. The minimum curves are
used to determine the highest energy levels absorbed by the surge arrester.
In Figure 2.12 is shown the construction of surge arrester for porcelain type.
Where in this figure, also has shown the arrangement of MOV inside the porcelain
housing. The blocks MOV is arrange in series along of surge arrester.
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Figure 2.12: Construction of Surge Arrester for Porcelain Housing [12]
CHAPTER 3
ATP SURGE ARRESTER MODEL FOR SIMULATION
3.1 Introduction
This chapter will explain about surge arrester model for simulation using computer
program called Analysis Transient Program (ATP). Whore this program is very similar
for studying in transient analysis and the result is must faster.
The entire parameters for modeling circuit either IEEE Model or Pinceti-
Gianettoni Model will be identified in this chapter. All these parameters will be
calculated using the formula as explained in the previous chapter.
Also this chapter will explain the differences of the input lightning waveform
between 50 kV to 200 kV. So to make it simple, three different inputs lightning
waveform is selected for this project which is 50 kV, 100 kV and 200 kV.
The type of metal oxide varistor or surge arrester is selected from two type of
surge arrester called Type 1 and Type 2. It is to understand the effect of lightning
impulse waveform when it is injected into these modeling circuits.
The entire output waveform for all simulation will be recorded for analysis and
further discussion in the next chapter.
3.2 Flow Chart of Project
22
This sub chapter will explain the simulation step by step from beginning until the output
waveform can be recorded. Figure 3.2 shows the flow chart of this project. This flow
chart is important because of it is the standard of procedure to complete this project.
With this flow chart, the mistake due to human error can be minimizing. It is also
easy to retrace and counter check all the process followed and not miss out. So, the flow
chart is very important for completing this project successfully.
23
Figure 3.1: Flow chart of Project
START
PREPARE THE MODELING CIRCUIT IN ATP SOFTWARE
CALCULATE THE PARAMETER OF R0, R1, L0, L1, C AND R
SETTING THE LIGHTNING IMPULSE WAVEFORM
IDENTIFY TYPE OF METAL OXIDE VARISTOR
SIMULATE CIRCUIT MODEL IN ATP SOFTWARE
RIGHT
RECORD THE OUTPUT WAVEFORM
END
YES
NO
24
3.2.1 Preparation Model of Surge Arrester in ATP Software
This project is divided by three sections, where the first section is the Input Section,
second section is the Modeling Circuit (IEEE Model or Pinceti-Gianettoni Model) and
the last section is the Output Section. Figure 3.2 is shows that the blocks diagram for
preparing the modeling circuit for surge arrester in the ATP software.
Figure 3.2: The blocks diagram for modeling circuit in ATP
3.2.1.1 IEEE Model Circuit in ATP Software
Figure 3.3: IEEE Model circuit draw in ATP software
Input (Lightning
Impulse Waveform)
Model of Surge
Arrester
Output (Load)
REFERENCES
[1] IEEE Working Group 3.4.11. Modeling of metal oxide surge arresters. IEEE
Transactions on Power Delivery. 1992, vol. 7, iss. 1, pp. 302{309.ISSN 0885-
8977. DOI: 10.1109/61.108922.
[2] PINCETI, P. and M. GIANNETTONI. A simplified model for zinc oxide surge
arresters. IEEE Transactions on Power Delivery. 1999, vol. 14, iss. 2, pp.
393{398. ISSN 0885-8977. DOI: 10.1109/61.754079.
[3] Gupta, T.K., 1990. Application of Zinc Oxide Varistors. Am. Ceramic J. Soc.,
73: 1817-1840.
[4] Ahmad, Z., 1994. Effect of Dry Band on Performance of UHV Surge Arrester
and Leakage Current Monitoring Using New Developed Model. Proceedings of
the 4th
International Conference on Properties and Applications of Dielectric
Materials, pp: 880-883.
[5] Daniel, W.D., 1985. Zinc-oxide Arrester Model for Fast Surges, EMTP
Newsletter, 5(1).
[6] Ravinda, P.S. and T.V.P Singh, 2002. Influence of Pollution on the Performance
of Metal Oxide Surge Arresters, Canadian Conference on Electrical and
Computer Engineering, pp: 224-229.
[7] Jonathan J Woodworth, History of Arrester on Power Systems 1890-1930,
ArrestersWorks.com 2011.
[8] Volker Hinrichsen, 2011, Metal-Oxide Surge Arresters in High Voltage Power
Systems – Fundamentals, Berlin and Darmstadt.
[9] V. A. Rakov, M. A. Uman, K. J. Rambo, M. I. Fernandez, R. J. Fischer, G. H.
Schnetzer, R. Thottappillil, A. Eybert-Berard, J. P. Berlandis, P. Lalande, A.
50
Bonamy, P. Laroche and A. Bondiou-Clergerie, "New Insights into Lightning
Processes from Triggered-Lightning Experiments in Florida and Alabama,"
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[10] Alternative Transient Program Rule Book (ATPRB), 1997. Can/Am EMTP User
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[11] Siemens AG Power Transmission and Distribution, www.siemens.com/arrester-
download
[12] http://download.schneiderlectric.com/files?p_File_Id=303175615&p_File_Name
=ECT 179.pdf
[13] Trin Saengsuwan and Wichet Thipprasert, The Lightning Arrester Modeling
Using ATP-EMTP, 2008
[14] M. A. Uman, “All About Lightning”. Toronto: Dover, 1986, pp. 1-158.
[15] Alternative Transient Program Rule Book (ATPRB), 1997. Can/Am EMTP User
Group,USA.
[16] M. A. Uman, “All About Lightning”. Toronto: Dover, 1986, pp. 1-158.
[17] J.P. Mackevich, "Proper Lightning Arrester Application Improves Distribution
System Reliability" presented at the IIE 2nd Int. Conf. Advances in Power
System Control, Operation and Management, Hong Kong, December, 1993.
[18] J.A. Martinez and D.W. Durbak, Parameter Determination for Modeling
Systems Transients – Part V: Surge Arresters, IEEE Transections on Power
Delivery, Vol. 20, No. 3, July 2005
[19] Pramuk Unahalekhaka, Simplified Modeling of Metal Oxide Surge Arresters,
Authors. Published, 2014
[20] Shehab Abdulwadood ALI, Design of Lightning Arresters for Electrical Power
Systems Protection, 2013
[21] Modeling of Metal Oxide Surge Arrester, IEEE Working Group 3.4.11
Application of Surge Protective Devices Subcommittee, Surge Protective
Devices Committee