lightning protection: history and modern approaches packet/ams 06.pdf · lightning protection:...

Lightning Protection History and

Modern Approaches

Department of Electrical and Computer Engineering

University of Florida Gainesville

86th AMS Annual Meeting

2nd Conference on Meteorological Applications of Lightning

Atlanta Georgia January 29 ndash February 2 2006

Vladimir A Rakov

2

2

Lightning Protection History and Modern Approaches

1 Franklin rod system

2 ldquoFaraday cagerdquo approach

3 Placement of air terminals

4 Behavior of grounding systems under direct lightning strike

conditions

5 Bonding Requirements

6 Non-conventional approaches to lightning protection

3

1 Franklin rod system (first described in 1753)

Lightning protection system for houses proposed (most likely by G Ch Lichtenberg) in

1778 Adapted from Wiesinger and Zischank (1995)

Air terminal

Down conductor

Ground terminal

4


Metallic roofs whose thickness is 48 mm (316 in) or greater do not require air

terminals (NFPA 780)

Air terminal

Down conductor

Ground terminal

Air terminal locations (UL 96A Fig 62 1998)

A= 20 feet (6 m) maximum

spacing for 10 inch (254

mm) air terminal height or

25 feet (76 m) maximum


mm) air terminal height

B= 2 feet (610 mm) maximum

spacing from corner roof

edge or ridge end

5

In 1876 James Clerk Maxwell

proposed that a gunpowder building

be completely enclosed with metal

of sufficient thickness forming what

is now referred to as a Faraday

cage

If lightning were to strike a metal-

enclosed building the current would

be constrained to the exterior of the

metal enclosure and it would not

even be necessary to ground this

enclosure In the later case the

lightning would merely produce an

arc from the enclosure to earth

The Faraday cage effect is provided

by all-metal cars and airplanes

Modern steel-frame buildings with

reinforcing metal bars in the

concrete foundation connected to

the building steel provide a good

approximation to a Faraday cage

The general principles of topological

shielding Adapted from Vance (1980)


Zone 1

Zone 3

Zone 1

Zone 2

1

10

22 3

Zone 0

SPD = Surge Protective Device

6


Lightning strike to a car with a live rabbit inside Courtesy of S Sumi

7

Video frame of a lightning strike to an aircraft on takeoff from the Kamatsu Air

Force Base Japan during winter Courtesy of Z I Kawasaki


8


Cape Canaveral Air Force Station Launch Pads 4041 Courtesy of R Kithil

9

Cape Canaveral Air Force Station Launch Pad 41 Courtesy of R Kithil


10

Illustration of capture surfaces of two towers and earthrsquos surface in the electrogeometrical

model (EGM) rs is the striking distance defined as the distance from the tip of the descending

leader to the object to be struck at the instant when an upward connecting leader is initiated

from this object Vertical arrows represent descending leaders assumed to be uniformly

distributed (Ng=const) above the capture surfaces Adapted from Bazelyan and Raizer (2000)


rs

rs

rs

Capture surfaces

Ng=const

Electrogeometrical model (EGM)

11


rs = 10 I065

m

where I is in kA

4

3

1

2

Striking distance rs versus return-stroke peak current I [curve 1 Golde (1945) curve 2 Wagner (1963)

curve 3 Love (1973) curve 4 Ruhling (1972) x theory of Davis (1962) estimates from two-

dimensional photographs by Eriksson (1978) estimates from three-dimensional photography by

Eriksson (1978) Adapted from Golde (1977) and Eriksson (1978)

I kA rs m

10 45

30 91

170 282

12

Scatter plot of impulse charge Q versus return-stroke

peak current I Note that both vertical and horizontal

scales are logarithmic The best fit to data I = 106 Q07

where Q is in coulombs and I is in kiloamperes was used

in deriving rs = 10 I065 Adapted from Berger (1972)


Finding rs = f(I)

bull Assume critical average

electric field between the

leader tip and the strike

object at the time of

initiation of upward

connecting leader from the

object (200-600 kVm)

bull Use an empirical relation

between Q and I to find

rs = f(I)

bull Finding rs = f(Q)

bull Assume leader geometry

total leader charge Q and

distribution of this charge

along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13


Illustration of the rolling-sphere method (RSM) The shaded area is that area into

which it is postulated lightning cannot enter Adapted from Szczerbinski (2000)

rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)

corresponds to I = 101 kA

(95 of currents exceed this value)

Rolling-Sphere Method

14

Photograph of surface arcing associated with the second stroke (current peak I=30 kA)

of flash 9312 triggered at Fort McClellan Alabama (Rg=260 Ω) The lightning

channel is outside the field of view One of the surface arcs approached the right edge

of the photograph a distance of 10 m from the rocket launcher Adapted from Fisher

et al (1994) V= I x Rg=78 MV

4 Behavior of grounding systems under direct lightning strike conditions

15


Illustration of safety distances in the soil (Dsoil) and in air (Dair) Adapted from

Kuzhekin et al (2003)

LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb

If I = 60 kA Zg = 25 Ω and Eb= 300 kVm Dsoil = 5 m

Dair = 012Zg+01L

I = the lightning peak

current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil

Bond whenever you cannot adequately isolate

16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17

The IEEE peak current distribution given by equation (1) and corresponding values of Dsoil

given by equation (2)

(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17


Bonding of external services near ground level Taken from Wiesinger and

Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18


Early Streamer Emission (ESE) systems

Lightning struck point B (without air terminal) which was within the claimed protection radius of

30 m of the ESE air terminal at point A The distance between A and B is 18 m After the strike

the manufacturer installed an additional ESE Terminal at point B Taken from Chrzan and

Hartono (2003)

19


Lightning elimination systems

Evolution of lightning elimination

(dissipation) system claims

However

Multipoint corona systems (dissipation arrays) provide only local lightning protection They

reduce the number of lightning strikes to their own surface and the object components

directly covered by them The question of extending the protection area of such systems

still remains open (Aleksandrov et al 2005)

bull Corona current can discharge the

thundercloud

bull Corona charge can neutralize an

approaching lightning leader

bull Corona charge can suppress or

delay the formation of an upward


protected objectTaken from the European Power News February 2005

2020

Thank You

Lightning strike to the Washington Monument (169 m high) on July 1 2005

21


22

23

Surface arcing

2

2

Lightning Protection History and Modern Approaches




4 Behavior of grounding systems under direct lightning strike

conditions



3




Air terminal

Down conductor

Ground terminal

4




Air terminal

Down conductor

Ground terminal










edge or ridge end

5






cage



















Zone 1

Zone 3

Zone 1

Zone 2

1

10

22 3

Zone 0


6



7




8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

3




Air terminal

Down conductor

Ground terminal

4




Air terminal

Down conductor

Ground terminal










edge or ridge end

5






cage



















Zone 1

Zone 3

Zone 1

Zone 2

1

10

22 3

Zone 0


6



7




8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

4




Air terminal

Down conductor

Ground terminal










edge or ridge end

5






cage



















Zone 1

Zone 3

Zone 1

Zone 2

1

10

22 3

Zone 0


6



7




8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

5






cage



















Zone 1

Zone 3

Zone 1

Zone 2

1

10

22 3

Zone 0


6



7




8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

6



7




8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

7




8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

8



9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

9



10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

10







rs

rs

rs

Capture surfaces

Ng=const


11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

11


rs = 10 I065

m

where I is in kA

4

3

1

2





I kA rs m

10 45

30 91

170 282

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

12







Finding rs = f(I)










rs = f(I)





along the channel

Q

10-1

100

101

102

100 101 102

I

I peak Q impulse

neg first strokes

n=89

I = 106 Q07

For Q = 5 C

I = 33 kA

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

13




rs

rs

rs

rs = 46 m (150 ft)

(NFPA 780 2004)




14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

14





et al (1994) V= I x Rg=78 MV


15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

15




LPS down conductor

LPS grounding

system

Protected ObjectL

Buried Services

Wooden pole

LPS air terminal

Dair

Dsoil

Dsoil = I Zg Eb


Dair = 012Zg+01L


current

Zg = the grounding

impedance

Eb = the breakdown

electric field in

the soil


16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

16


Peak current I

kA 5 10 20 40 60 80 100 200

Percentage

exceeding

tabulated value

ΡI 100

99 95 76 34 15 78 45 08

Dsoil m (Zg = 25

Ω Eb = 300

kVm)

042 083 17 33 50 67 83 17



(1) (2)PI = 1 + (I 31)26

1Dsoil = IZgEb m

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

17



Zischank (1995)

structure

clamp gap

information line

power linepipe

arrester

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

18






Hartono (2003)

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

19





However






thundercloud







2020

Thank You


21


22

23

Surface arcing

2020

Thank You


21


22

23

Surface arcing

21


22

23

Surface arcing

22

23

Surface arcing

23

Surface arcing

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