E11 - 4
2011 International Conference on Electrical Engineering and Informatics
17-19 July 2011, Bandung, Indonesia
HV/EHV Transmission Lines Performance
Calculation of Lightning Stroke by Using
Corridor Method
Eko Yudo Pramono1), Reynaldo Zoro2) and Rizki Wahyuni1)
1)
Transmission and Load Dispatch Centre of Sumatra (PLN P3B Sumatera) / Planning Department,
Padang - West Sumatera, Indonesia
ekoyudo@p3b-sumatera.co.id
rizky_ayumi@yahoo.com
2)
Power Engineering Division, School of Electrical Engineering and Informatics (Institut Teknologi Bandung),Bandung –
West Java, Indonesia
zoro@hv.ee.itb.ac.id
Abstract-- High Voltage / Extra High Voltage (HV/EHV)
performance calculation of lightning stroke used to use
thunder days method. With the technology improvement
where it can be known the ground flash density, the
Lightning Performance of HV/EHV transmission lines
can be accurately done by using the ground flash density
in the region that are passed by the transmission lines.
To obtain the lightning performance similar to the flash
density, it is used a Corridor Method so it can be
evaluated the corelation between lightning stroke to the
ground with the failures data of which caused the trip.
Based on the performance calculation, when it is found
above the transmission lines standard design,
improvements are needed to increase the performance of
the transmission lines. With the tehnical and economical
optimation consideration, Corridor Method can be used
to determine all critical points along the transmission
lines, so it is easily known of which tower that must be
rapaired.
The calculation using Corridor Method provides detail
result in the terms of segmentation performance
evaluation because it is calculated of each corridor with
various ground flash density. Therefore, this calculation
become important as a reference in high voltage overhead line design and also in the transmission lines
performance calculation of Transmission and Load
Dispatch Centre of Sumatra for maintenance purpose.
Keywords-- Shielding Failure, Back Flashover, Ground
Flash Density,Corridor Method
I.
FOREWORD
Lightning stroke is a serious thread in electricity power
system which has vast coverage area like in High Voltage /
Extra High Voltage (HV/EHV) of over-head transmission
978-1-4577-0752-0/11/$26.00 ©2011 IEEE
line operated by PLN, a state-owned electricity company in
Indonesia, and it becomes a backbone in the electricity
power system.
Damage and loss as a result of the lightning stroke are
caused by:
• Lightning stroke at ground wire resulting back flashover
on isolator in transmission lines and substations, also in
transformer and other equipments in switchgear.
• Direct lightning stroke to phasa conductor because of
shielding failures in ground wire.
In addition, there are still no standard design of appropriate
protection systems for lightning threads in tropical region
that can be applied in PLN’s operational coverage area.
Changing parameter can be done through improvements in
protection system.
Purposes of this research are:
a. To learn the lightning charateristics on regions passed
by HV/EHV transmission lines.
b. To evaluate the lightning performance of HV/EHV
transmission lines by calculating the probability of
protection failures due to lightning stroke.
To improve the performance of lightning protection at
HV/EHV transmission lines with economical consideration
using severity index method.
II. LIGHTNING AT HV/EHV TRANSMISSION LINES
A. Lightning Parameter
1. Crest Current, Î [kA]
According to Hileman [1], Crest / Peak Current is
the peak current of return strokes. It is distinguished by
polarities, negative or positive, and also by its first
stroke or subsequent strokes.
2. Rate-of-rise of Current, di/dt [kA/μs]
According to Hileman [1], Rate-of-rise of lightning
current is a changing rate of current to time to attain its
crest. It is approached by a comparison of crest current
and crest time.
Quantity of Electricity, Q = ∫ dt . I
Quantity of electricity is an area of lightning stroke
or the integral of the current to time.
Lightning Energy, E = ∫ I2.dt
Lightning energy is a mechanic effect and also a
lightningheat.
3.
4.
B. Striking Distance Equation (r)
Striking Distance Equation used in this paper is
Whitehead’s equation [8] with consideration that this
equation is closer enough with the lightning stroke data in
Indonesia. The striking distance equation by Whitehead [8]
is:
r = 6.7 * I 0.85
(1)
Where I is Lightning Current
C. Back Flashover Ratio
C.1. Lightning Stroke on Tower
Tower can be represented as surge impedance or inductance.
When tower is represented as inductance, then the
adjustment of grounding resistance (R’0) and surge
impedance of ground wire (Z’g) according to Anderson [11]
can be calculated as:
2
⎛ Z ' g +2 R' 0 ⎞ 2 Z W τ t
⎟
L=⎜
⎟ (1 − ψ ) 2
⎜ Z'
g
⎠
⎝
di ⎞
⎛
V = C , I ( Z t + R0 ) = Co⎜ IR0 '+ L ⎟
dt ⎠
⎝
(4)
Whereas coupling for transmission with two ground wires
[11] is:
Co =
ln (b1 .b2 ) /(a1 .a 2 )
ln(2.hg / d .r )
(5)
Where, a and b is the distance between ground wire and
phase conductor with its reflection as shown in Fig. 2.
Fig. 2. Wire reflection at multi-conductor lines
In analyzing the transmission lines performance of lightning,
it is used differently resistance level called Critical Flasover
(CFO). According to ANSI C92.1 82 [21], CFO is the
maximum voltage of lightning impulse with the resistance
possibility as same as its failure possibility that is 50%. It
refers to the laboratorium test result of the isolator.
Isolator combination and configuration at transmission lines
will assign different CFO value. Eventough in transmission
lines, CFO isolator vary in value and combination, the least
CFO value will be used in calculation.
(2)
Where, R’0 is the adjustment of grounding resistance, Z’g is
surge impedance of ground wire, Zw is surge impedance, Ψ
is adjacent tower factor, and τt is tower travel time.
Overvoltages in tower as surge impedance is comparable
with lightning crest current, meanwhile for tower as
inductance comparable with the rate-of-rise current.
Therefore, overvoltages on the crest of tower is as follows
[11]:
The lightning stroke to ground striking one structure is
determined by the reflection of the structure. According to
[1]:
di
2 (3)
+ Vs
dt
3
Where, I is lightning crest current (kA), Ro is tower footing
resistance, L is tower inductance, di/dt is the rate-of-rise of
curret (kA), VS is system voltage (kV).
Where, NL is flash that might hit the structure
[flashovers/100km-year], Ng is Number Flash to Ground
[flashes/100km/year], h is the height of structure [m], d is
structure width or as same as 2b [m]
V = I ( Z t + R0 ) = I .R0 '+ L
Fig. 3. Reflection Illustration of Ground Wire Protection
⎛ 28.h 0.6 + d ⎞
⎟⎟
N L = N g ⎜⎜
10
⎝
⎠
(7)
Therefore, the performance of this transmission line is [15]:
∞
BFOR = 0.6 N L ∫ f ( I ) di = 0.6 N L P( I c )
(8)
Ic
Fig. 1. Tower representation as surge impedance and
inductance.
C.2
Lightning Stroke on Ground Wire
When lightning strikes ground wire, a portion of
lightning current flew to ground through towers. Therefore,
the overvoltage in isolator [11] is:
D. Shielding Failure Ratio
Shielding Failure – SF, according to Anderson [11], means
the ground wire failure to protect phase conductor from the
lightning stroke due to the imperfection of ground wire
location on tower.
The calculation is done by Anderson method [11] used
as IEEE 1243 standard [13].
This imperfection will give chances of lightning to
strike the region that is unprotected by ground wire.
According to Hileman [1], the unprotected region is
ilustrated in Fig. 4 and the effective protection is ilustrated
in Fig. 5.
Fig. 4. Protection of the imperfection ground wire
Fig. 5. Perfectly Ground Wire Protection
To calculate the ratio of isolator creepage, it is necessary to
find out the gradien of the voltage withstand creepage
isolator as follows [11]:
(9)
E0 = VLN / n.s … [kV/m]
Where, VLN is phase to ground voltage (kV), n is the number
of sheds insulator, and s is creepage distance (m)
Whereas, the probability of flashover becoming failure
[11], is:
η = 0.3196 ln(e) − 0.6578
(10)
Therefore, the failure number due to the Shielding
Failure, SFFOR [11] is:
SFFOR = 0 . 5η P ( I MAX ) X s 0 . 1 N g
(11)
[ failure / 100 km / year ]
SFFORTotal = ∑ SFFOR
(12)
E. The Perfomance of Transmission Lines to the
Lightning
lightning, LC is the failure number of the ligthning
correlated, dan L is the length of transmission lines (km).
Based on the failures recapitulation data, failures caused
by, the Ligthning Performance / LP is approached by:
a. Failures that are surely caused by lightning or
called Sure Lightning / SR: it is decided that the
failures are because of lightning based on evidence
at the site, e.g: broken insulator, burned or
discharged conductor, and by the justification of
site officer who observes the trouble a moment
after the lightning stroke or the thunder.
b. Failures that is assumed correlating with lightning
stroke or indirect effects of ligthning stroke called
Lightning Correlated / LC are: failures based on
weather at the trouble time (or bad weather: rain,
downpour, cloudy, drizzle,foggy), cryptyc failures
and failures based on the damage of equipment in
lines (e.g. transformer, lightning arrester, insulator,
etc). It is assumed only about 70% of these kind of
failure correlated with lightning stroke [1].
III.
RESEARCH DATA (An example case
of Paiton-Kediri EHV 500 kV Transmission
Lines)
A.
Failures Data
Lightning has substantial portion as the failures cause. It
is considered by the evidence in observation at the site e.g:
trace of flashover on insulator, conductor ( broken or burnt)
or weather at the time of trouble. Percentage of failure type
on EHV 500 kV at East Java and Bali Region in 2005 is as
follows:
c.
Table 1.
Failures Classification based on the Causes in 2005
Code Type of Failure
Explanation of Causes
A
Equipment
Damage of components
Relay
B
Malfunction of relays
Malfunction
Earth quake, land slide,
Nature /
C
Rain / downpour,
Weather
Lightning, heavy rain
D
Kite
Kites
E
Tree
Tree, branch, twig
F
Animal
All animals
G
Human Eror
H
Over Load
I
Distribution
J
Miscellanea
Deviation of the Standard
Operating Procedur or
Fixed Procedur
%
21.28
2.12
23.40
0.00
19.15
4.26
0.00
Lightning over voltage in transmission lines can cause
failures stated by Flashover Rate (FOR). According to IEEE
1243 [13], FOR is the number of flashover in insulator
because of the lightning over voltage in transmission lines.
If the lightning performance is equal to FOR or assumed that
failure happens everytime of flashover, in this case the
calculated value is the worst possibility.
To calculate the lightning performance of the failure
data, it is used an equation of Cliff. J.S [10], as follows:
(SR + LC ) )
(13)
LP = 100
L
The failure percentage of nature (a dominant lightning)
is 23.40 %. Therefore, it is necessary to enhance efforts of
protection system upgrading about failures expecially for
lightning. Therefore, 23,40 % can be minimized as small as
reasonably possible.
Where,
LP
is
the
Lightning
Performance
(failures/100km/year), SR is the failure number of the sure
d. Table 2
Performance of Paiton – Kediri EHV 500 kVderived from trip
and reclosed failure data
Over load (transmission &
transformer)
Feeder
APFL, flying items, fire,
Telecommunication and
SCADA, investigated cases
TOTAL
0.00
0.00
29.79
100
Year
2003
2004
2005
2006
Sure
Lightning
Ligthning
Lightning Correlated Performance
4
2
3.04
2
2
2.03
3
0
1.52
3
1
2.03
From table 2, it is known that the Lightning
Performance of Paiton – Kediri EHV 500 kV has exceeded
the PLN’s standard design of EHV 500 kV that is 1.1
failures/100 km/year [22].
B. Broken Insulator Data
A number of broken insulators since 2003 are 308 pieces of
insulator. In Fig. 6, it is shown the correlation between
broken insulator data with the lightning stroke event data,
therefore it is known that the main cause of broken insulator
is lightning.
D. Lightning Data of each Corridor
In increasing the accuracy of the lightning current
calculation and the relevance of lightning data to the regions
of which are observed used some corridors. Corridor that is
used has a square in shape with 10 km length as in Fig. 3.7.
Each corridor averagely consists of 25 towers, therefore
there are totally 19 corridors.
For lightning stroke complete data of each corridor is shown
in Appendix 1 in which each corridor length is 10 km x 10
km, and in Paiton – Kediri EHV 500 kV Transmission Lines
Corridor is made 1 km x 1 km to observe lightning stroke
data nearby the transmission lines.
Jalur Transmisi SUTET 500 kV Paiton-Kediri
PT PLN (persero) P3B Region Jawa Timur dan Bali
W indow 10 x 10 km
Koridor 1 km
Petir Tahun 1999-2000
-10.25
-11.25
T 126
-12.25
-13.25
-14.25
T 101
-15.25
-16.25
Statistik Variansi Bulanan Kejadian Petir di Wilayah Jawa Timur
(1 Januari - 31 Desember 1999), Center 7.75023 S 112.8069 E, Window 200 x 60 Km2
-17.25
7000
25
-18.25
6000
-19.25
20
-20.25
-45.8
5000
15
Bin
4000
3000
10
-44.8
-43.8
-42.8
-41.8
-40.8
-39.8
-38.8
-37.8
-36.8
-35.8
Fig. 7 Example of research corridor number 5 (1 x 1 km) in window of
size ukuran 10 x 10 km
2000
5
1000
0
0
Jan
Feb
Mar
Apr
Mei
Jun
Jul
Aug
Sep
Okt
Nov
Des
Bulan
2003
2004
2005
2006
Petir Positif
Petir Negatif
Flash event probability with crest current in corridor
number 5 is :
Petir Awan
Statistik Probabilitas Arus Puncak Kejadian Petir di Wilayah Jawa Timur
Koridor 5
Fig. 6. Correlation between Monthly Lightning Events Variation and
Broken Insulators.
100
90
80
P ro b a b ilit a s [ % ]
70
C. Lightning Data
60
50
40
30
20
Lightning data taken from lightning historical data are
lightning stroke to ground data recorded by lightning
detection system. From the National Lightning Data
Network, known as JADPEN / Jaringan Data Petir Nasional,
this network uses technology to determine the lightning
stroke position known as LPATS (Lightning Position and
Tracking System).
Data used in this research are the historical data since
1996 – 2001. From this historical data,it is acquired
lightning parameters e.g.: crest current, event probability,
event monthly variation, event frequency and ground flash
density. To find out the lightning influence to the
transmission lines, it is necessary to do the mapping using
GPS (Global Positioning System) data of the Paiton – Kediri
EHV 500 kV Transmission Lines and becoming the
boundary of observed region.
Lightning data in this region is generally summarized as
follows :
Table 3.
Lightning Characteristic in region passed by the Paiton – Kediri EHV 500
kV Transmission Lines
Negative Positive
Polarity Polarity
Maximum
340.2
290.52
29
20
Crest Probability 85%
Probability 50%
47
32
Current
Probability 2%
140
160
Average
69.3
63
3-12
Total Flash Density
Lightning Characteristic
10
0
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
Arus Puncak [kA]
Negative 1st
Negative Subsequent
Positive 1st
Positive Subsequent
Fig. 8 Example of crest current probability in research corridor number 5 (1
x 1 km) at window with length 10 x 10 km.
Lightning data of each corridor will be processed in the
range of frequency to get the crest current probability.
Py =
100
⎛ ⎛ x ⎞b ⎞
⎜1 + ⎜ ⎟ ⎟
⎜ ⎝a⎠ ⎟
⎝
⎠
(14)
Where;
Py = Crest Current Probability
x = Crest Current
a = Median of Crest Current
b = searched value
E.
Tower Data
Paiton – Kediri EHV 500 kV cone type - one tower
and two circuits with two ground wires as in Fig. 9.
Grounding used on tower is counterpoise type connecting
with the four legs of tower in depth about 1.5 meters using
95 mm2 BC (Brown Copper) wires and some 1.5” iron pipes.
Composition of the tower height varies from
68,625 meters to 86,625 meters, but the most common usage
is 77,625 meters as many as 172 units or approximately
34.82 %, and the highest tower is 86,625 meters 7 units.
Table 4.
Tower composition based on the tower height
No
1
2
3
4
5
6
7
Tower
Quantity Percentage
Height (m) (units)
(%)
68.625
26
5.26
71.625
92
18.62
74.625
119
24.09
77.625
172
34.82
80.625
58
11.74
83.625
20
4.05
86.625
7
1.42
Fig. 12. Magnetic band recording at the time of lightning stroke on tower
353rd on February 5th, 2007.
Fig.13. CVT fiber support condition after he lightning stroke at tower 353th
on February 5th, 2007
IV.
EVALUATION RESULT
A. The Calculation of Ground Wire Shielding Failure
Fig. 9. The tower of EHV 500 kV Paiton-Kediri (typical)
F. Site Observation Data
Shielding Failure Flashover Rate as Function of Over Head Ground Wire Height at Tower
in Various Ground Flash Density
0.5
NG=16
NG=14
0.4
SFFOR [outage/100km/year]
Lightning observation in EHV 500 kV transmission lines is
done by installing equipments at two towers of Paiton –
Kediri number 103 and 353. Location election of measuring
equipments based on considerations of the two towers which
has high flash density and the high number of failures as in
failures data.
The installed equipment consisted of Finial CVT
(Collection Volume Terminal) in Fig. 10, is an air terminal
in external lightning protection system having function to
transmit up streamer so that it is potential enough to be
struck by lightning rather than the conventional finial and
measuring equipments.
Installed measuring equipments are magnetic band and LEC
(Ligthning Counter Event) as in Fig. 11,where magnetic
band is used to record the value of the crest current striking
the finial and LEC is a device used to count the sum of
lightning that strikes the finial, where the sum will increase
when lightning stroke happens.
From the calculation, it is known that minimum current
causing Shielding Failure (SF) is 14 kA, with the correlation
of S.Hidayat’s research result [20] then this current has
probability about 87.5 %.
From Fig. 14 it is known that the higher tower, the bigger
Shielding Failure ratio. For tower having height as the
typical tower data that is 72,625 meters, it has excellent
shielding failure ratio, below the standard design as the
formula of Brown-Whitehead and IEEE-1992 [8], that is
0.05 failures/100 km/year.
Whereas, for tower with height is above the typical, its
shielding failure ratio will increase and getting bigger when
its lightning flash density getting denser.
From the Paiton – Kediri EHV 500 kV tower data, there are
more tower with the height of 77,625 meters as many as
34.82 %. For tower with height 77,625 meters, its shielding
failure ratio is 0.07 failures/100km/year in the region with
flash density 12 flashes/km2/year.
NG=12
0.3
NG=10
NG=8
0.2
NG=6
NG=4
0.1
NG=2
0.0
68.0
71.0
74.0
77.0
80.0
83.0
86.0
OHGW Height at Tower [m]
Fig. 10. CVT on tower 353rd
Ng = 2 flash/km2/yr
Ng = 4 flash/km2/yr
Ng = 6 flash/km2/yr
Ng = 8 flash/km2/yr
Ng = 10 flash/km2/yr
Ng = 12 flash/km2/yr
Ng = 14 flash/km2/yr
Ng = 16 flash/km2/yr
Fig. 14. SFFOR as tower height function in various flash density
B. Back Flashover Rate
Fig. 11. LEC and magnetic band
Measuring equipments installation were done on
December 2006 and the observation continues doing at the
present time. Data recorded at LEC are two lightning stroke
data striking tower 353rd. From the data, it is known that the
values of their crest current are 26 kA and 34.8 kA, where
Fig. 12 shows the magnetic band recording.
From Fig. 15, when there is a lightning stroke at tower,
it is possible to calculate the crest voltage of tower using the
3rd equation. Crest current used in this case is the crest
current with 50% percents probability in the research result
of S.Hidayat [20] that is 26 kA. It is chosen by the
consideration that crest current is as same as the result of
field research and if it correlates with the research of R.Zoro
[14], then probability of the crest current 26 kA is 75 %.
When it is correlated with JADPEN’s data for regions
In Fig. 19, the total BFOR in the region with maximum flash
density is 12 flashes/km2/year and the tower legs impedance
is 0.7 failures /100km/year.
Rasio Lewat Denyar Balik Fungsi Tahanan Kaki antara 5 Ohm hingga 20 Ohm fungsi tinggi menara SUTET 500 kV
dengan Kerapatan Sambaran Petir ke Tanah sebesar 12 sambaran/km2/tahun
2
86.625
1.75
77.6 25
83.625
1.5
B F O R [g a n g g u a n /1 0 0 k m / ta h u n ]
passed by the Paiton-Kediri EHV 500 kV transmission lines,
the probability of crest current 26 kA is 85 %.
Based on calculation result in Fig. 15 and 16, it is
known that if the impedance of tower legs is 10 ohms, then
voltage at the top of tower is 2168 kV. This voltage is higher
than the CFO voltage, so that there is a back flashover with
probability above 50 %.
74.6 25
80.625
1.25
71.625
1
68.625
0.75
0.5
0.25
0
0
5
10
15
20
R [ohm]
Tinggi Menara 68.625 m
Tinggi Menara 71.625 m
Tinggi Menara 74.625 m
Tinggi Menara 80.625 m
Tinggi Menara 83.625 m
Tinggi Menara 86.625 m
Tinggi Menara 77.625 m
Fig. 19. BFOR of tower legs impedanceof which flash density 12
flashes/km2/year for various tower height.
D. Sensitivity Analysis
Fig. 15. Voltage in tower as the tower legs impedance function
Fig. 16. Tower voltage of the tower legs impedance functionfor various
tower height
C.
Direct lightning stroke on ground wire
In Fig. 17 and 18, it can be seen the back flashover in
insulator due to the lightning stroke on ground wire. It
happens when ground impedance as same as or more than
25 ohms. The most often disturbed insulator is the insulator
of phase A.
This shows that lightning stroke on ground wire is spanned
between tower, is not dominant cause of the back flashover,
because whenever lightning stroke happens then the current
is divided into two oppposite direction to each tower facing
each other, so that the value is smaller than the lightning
stroke on tower.
In Fig. 17, tower legs impedance relates to BFOR. The
bigger value of the tower legs impedance is the higher
BFOR value and the flash density in the region passed by
the EHV 500 kV transmission lines will also be effected by
the BFOR. When flash density is getting denser, value of
BFOR increases.
Tower height also influences the BFOR value. The higher
tower is the more BFOR value as shown in Fig. 19. This
shows that BFOR is influenced by the value of tower legs
impedance, tower height and flash density in the region
passed by the EHV 500 kV transmission lines.
E. Calculating the Lightning Performance of Paiton –
Kediri EHV 500 kV Transmission Lines
1
2
Lightning performance estimation for EHV 500 kV
transmission lines which ground impedance is
approximately 10 ohms and flash density is maximum
12 flashes/km2/year is as follows:
FOR = BFOR + SFFOR
= 0.70 + 0.071
= 0.771 failures/100 km/year
From the data, it is known that the number of towers are
493 units in which the average span is 400 meters, and
the length of the transmission lines is approximately
197.2 km, so that the failure total possibility in a year is:
Failure total = 0.771 x 197.2/100
= 1.52 failures/100 km/year
F. The Lightning Performance using Corridor Method
Fig. 17. Voltage felt by insulator as the function of tower legs impedance
Rasio Lewat Denyar Balik Fungsi Tahanan Kaki antara 5 Ohm hingga 25 Ohm Tower SUTET 500 kV (77.625 m)
Untuk Berbagai Kerapatan Sambaran Petir ke Tanah
2
Ng=16
Ng=6
1.75
Ng=14
Ng=4
B F O R [g a n g g u a n /1 0 0 k m / ta h u n ]
1.5
Ng=12
Ng=2
1.25
Ng=10
1
Ng=8
0.75
0.5
0.25
0
0
5
10
15
20
25
R [ohm]
Ng = 16 flash/km2/yr
Ng = 14 flash/k m2/yr
Ng = 12 flash/km2/yr
Ng = 10 flash/km2/yr
Ng = 8 flash/km2/yr
Ng = 6 flash/km2/yr
Ng = 4 flash/k m2/yr
Ng = 2 flash/km2/yr
Fig. 18. The average back flashover of EHV 500 kV tower legs impedance
(77,625 meters) for various ground flash density.
By using the same way, it can be known the lightning
performance of each corridor with the calculation of flash
density and ground flash probability of each corridor. The
lightning peformance of each corridor becomes the lightning
performance of along the EHV transmission lines. This
method is also useful in determining the recovery priority.
To calculate the lightning performance of each
corridor, it uses the same way as the lightning performance
calculation by first method, but data used are only data of
each corridor. In table 5, it shows the lightning performance
result of each corridor.
The result of table 5 shows that the total lightning
performance of Paiton – Kediri EHV 500 kV as the sum of
each corridor peformance is 1.515 failures/100 km/year.
This indicates that these EHV 500 kV trasmission lines have
exceeded the standard design of EHV 500 kV tansmission
lines in the region of Java – Bali Transmission and Load
Dispatch Centre.
If the lightning performance of each corridor
compares to the lightning performance of first method, the
result is not quiet different that is approximately 1.5
failures/100 km/year. Corridor which has the highest FOR is
the 2nd corridor.
Table 5.
EHV 500 kV Transmission Lines Lightning Performance Calculation
Result of each Corridor
Corri
dor
Tower
Number
Lightning
Ng
SFFOR
BFOR
P f
Flashes/k Failures/ Flashes/k Flashes/k Flashes/k
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
T1-T25
T26-T50
T51-T75
T75-T100
T101-T125
T126-T150
T151-T175
T176-T200
T201-T225
T226-T250
T251-T275
T276-T300
T301-T325
T326-T350
T351-T375
T376-T400
T401-T425
T426-T450
T451-T496
m2/year
0.626
2.128
1.151
0.657
0.952
0.959
0.843
0.174
1.164
0.798
m2/year
0.642
2.182
1.166
0.671
0.968
0.975
0.854
0.209
1.248
0.846
m2/year
0.067
0.227
0.121
0.671
0.101
0.101
0.089
0.022
0.130
0.088
0.306
0.711
0.565
0.473
0.246
1.409
0.171
0.296
0.146
0.352
0.764
0.642
0.532
0.280
1.476
0.205
0.359
0.184
14.556
0.037
0.079
0.067
0.055
0.029
0.154
0.021
0.037
0.021
1.515
m2/year km2/year
4.20
0.016
4.15
0.054
3.17
0.015
3.80
0.013
3.50
0.016
3.65
0.016
3.90
0.011
5.25
0.035
7.15
0.084
7.10
0.048
10.35
0.046
10.75
0.053
11.15
0.077
11.55
0.059
9.2
0.034
4.9
0.067
3.25
0.034
4.15
0.063
4.57
0.037
TOTAL
V.
CONCLUSIONS
1.
The lightning performance of HV/EHV transmission
lines is more accurate by using the ground flash density
data than using the thunder days method. To get the
flash density data, it is required the detection
equipments of the lightning stroke.
2.
Lightning performance using level method gives the
same result as the corridor method that is 1.5
failures/100 km/year. This is similar with the failure
data in 2005 that is 1.5 failures/100 km/year.
3.
The calculation using corridor method gives more
comprehensive result of lightning performance
becauseit calculates performance of each corridor which
has different flash density.
4.
For the design of EHV transmission lines building, it is
necessary required the flash density data and lightning
parameter in the region passed by the EHV transmission
lines, because it will be very influential for the
HV/EHV transmission lines performance at operation
time.
The performance evaluation method of HV/EHV
transmission lines can be applied as reference of
Transmission Lines Outage Frequency (TLOF) at the
HV/EHV Transmission Lines Operation and Maintenance
Unit
REFERENCES
[1] Hileman, A.R., ‘Insulation Coordination for Power Systems’, Marcel
Dekker, Inc., New York, 1999.
[2] Chowduri, P., ‘Electromagnetic Transients in Power Systems’,
Research Studies Press Ltd., Taunton, 1996.
[3] Uman, M.A., ‘Lightning’, Dover Publications, Inc., New York, 1969.
[4] Berger, K., ‘The Earth Flash’, in the Lightning Volume 1: Physics of
Lightning, Bob Golde, R.H., Editor, Academic Press, London, 1977,
page 119 – 190.
[5] Golde, R.H., ‘Lightning Current and Related Parameters’, in the
Lightning Volume 1: Physics of Lightning, Chapter 5, Golde, R.H.,
Editor, Academic Press, London, 1977, page 309 – 350.
[6] Ragaller, K., ‘Surge in High Voltage Networks’, Plenum Publishing,
Co., New York, 1980.
[7] Visacro, S., Dias, R.N., Mesquita, C.R., Vale, M.H.M., ‘A
Methodology Based on Severity Indexes to Determine Critical Spots
along Transmission Lines Concerning Lightning Performance’, Proc.
27th International Conference on Lightning Protection, Avignon,
2004, matter of 6b2.
[8] Whitehead, E.R., ‘Protection of Transmission Lines’, in the Lightning
Volume 2 : Lightning Protection, Chapter 22, Golde, R.H., Editor,
Academic Press, London, 1977, page 697 – 746.
[9] Rusck, S., ‘Protection of Distribution Systems’, in the Lightning
Volume 2 : Lightning Protection, Chapter 23, Golde, R.H., Editor,
Academic Press, London, 1977, page 747 – 772.
[10] Cliff, J.S., ‘Insulation Coordination’, in the Lightning Volume 2 :
Lightning Protection, Chapter 24, Golde, R.H., Editor, Academic
Press, London, 1977, page 773 – 792.
[11] Anderson, J.G., ‘Lightning Performance of Transmission Lines’, in
the Transmission Lines Reference Book : 345 kV and Above, Chapter
12, LaForest, J.J., Editor, Palo Alto, California, 1982, page 545 – 597.
[12] Zoro, R., ‘Proteksi Terhadap Tegangan Lebih pada Sistem Tenaga
Listrik (Surge Protection)’, in the Proteksi Sistem Tenaga Bagian I ,
ITB, Bandung, 1987.
[13] IEEE, ‘IEEE Guide for Improving the Lightning Performance of
Transmission Lines’, IEEE Standard 1243-1997, Dec. 1997.
[14] Zoro., R., ’Karakteristik Petir dan Kondisi Cuaca di Daerah Tropis:
Kasus di Gn. Tangkuban Perahu Indonesia’, Disertasi Program
Doktor, ITB, Bandung, 1999.
[15] CIGRE Working Group 01 of study committee 33, ‘Guide To
Procedures For Estimating The Lightning Performance of
Transmission Lines’, Electra, Paris, 1991.
[16] Chowduri, P., ‘Parameters of Lightning Strokes and Their Effects on
Power Systems’, Proc. of IEEE/PES Transmission and Distribution
Conference and Exposition, Atlanta, 2005.
[17] Berger, G., Zoro, R., ‘Lightning Density in Indonesia: Is the Guinness
Book of Records Right?’, Proc. in International Conference on
Grounding and Earthing and 1st International Conference on
Lighting Physics and Effects, Belo Horizonte, 2004, page 34 – 37.
[18] Zoro, R., Bambang, S., Mefiardhi, R., ‘Evaluation and Improvement
of Lightning Protection on Transmission and Distribution Lines Using
Lightning Detection Network’, Proc. in 27th International
Conference on Lightning Protection, Avignon, 2004, matter of 6p13.
[19] Hidayat, S., Zoro, R., ‘Observation of Lightning Discharges in
Indonesia by lightning Detection Network’, Proc in ICPADM 2006,
Vol 2, Denpasar Bali. 2006, matter of number P3-30.
[20] Hidayat, S., Ishii, M. ‘Lightning Discharge on Land and Sea in
Indonesia,’ Proc in ICPADM 2006, Vol 1, Denpasar Bali. 2006,
matter of K-7.
[21] ANSI C92.1-1982, ‘American National Standard for Power System
Insulation Coordination’, ANSI, New York, 1982.
[22] Prasetijo, Dj., ’Operating Experiences With EHV Transmission
Sistem in Java’, Jurnal Teknik Tegangan Tinggi Indonesia, Inter
University Engineering Study Forum of High Voltage, Jakarta, 1999