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CHƯƠNG 1
TÍNH TOÁN BẢO VỆ CHỐNG SÉT ĐÁNH TRỰC TIẾP
VÀO TRẠM BIẾN ÁP 220/110 kV
1.1. Mở đầu
%&&'()*+),-.
/0,%12()*+345#6)'
778370
9:;1<=4<>7#1
35?.,*@')()4-AB%:7
CD)#E=0FGHIH
E-#0J',8=:,7)8)
*0
95<*KL&)%E
K.,0KMN*,%')51:
3')317K:*#)
*1,0
O)3K.,1*5KPKIQ#)
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')NB5KI&*G>*#3
KI()*;7&')#EN%:5.,3
=1830R*##
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6()*U5N*0
1.2. Các yêu cầu đối với hệ thống chống sét đánh thẳng
V7)8):N*%G
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9: !#$*KL&)%E>I:<K., !#$*KL
K.,0
9: !#$32*>K33541
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!
<%G,#
αj !
!
÷ ]
!
1.4. Mô tả đối tượng bảo vệ
` !#$"!#$>o*,__
`-)& !
`-)K !
`b*!#$*c>b* !#$*g0
`Fo4W;?
FR),^$_`O9`#] $9`<9+a\*OR&
]
!"!#$
210
120
5
5
8x17=1366
5
5
15x10=150

11m
11m 11m 11m 11m 11m
11m 11m 17m 11m 11m
Bể n ớc
Trạm bơm
cứu hỏa
Nhà
điều khiển
Nhà QLVH
TN2
TN1
Bể dầu sự cố
AT1 AT2
8m
FR),^$_`O9`#] $9`<9+a\*OR&
e
!"!#$
1.5. Tớnh toỏn, la chn cỏc phng ỏn bo v chng sột ỏnh thng
cho trm bin ỏp
1.5.1. Phng ỏn 1
Hình 1.7: Sơ đồ bố trí các cột thu lôi của ph ơng án 1
4
4.5
AT1 AT2
4
4
11m
17m 17m 17m 17m17m
17m
11m

15
16 17 18 19 20 21
22 23 24 25 26 27
8m 8m 8m 8m 8m
FR),^$_`O9`#] $9`<9+a\*OR&
g
 !"!#$
*+,+*+*-&.
`d* !#$]&
`d*!#$ &
&)%E 7b*g 7b* 7b*c
d* !#$
&> >Z>[>]>>

&e>g>c>n>!
d*!#$
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!> 
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95=&*KMN*&)*b1=<
#<I*()*.&J09&*KMh
-)#
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c
3
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

FR),^$_`O9`#] $9`<9+a\*OR&
c
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40.**56
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ZD>Acpnp ]p [D>Anp !p ep ]D>A !p p gp eD%

Z! Z!>] [ >gcA D3 
= + =
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[ >gc
]>Z]A D
c c

3
 
= = =
*3#()%)*)
Bảng 1.2.7#2"'(
qDr@*! !#$
s<#<I*ApgpcD>Apcp D>
A pnpcD>A pnp !D>A p !pZD>AZp p !D>AZp p[D>A[p p]D>*G,
$:%i*)p*>>%pF>tJ%8%=%K>#
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
A DA DA D8       
= − − −

[

8
= = =
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Z[>ec
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c c
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3
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Bảng 1.3. 7#2"'(
R',*35%G,&*KM)&%e>]AD
9&*&)%E*!#$%
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= + = + =
9&*&)%E* !#$%
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0 !":;
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!
Z!
g>] Z> A D
g g
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  
= − = − =
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
!


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g>]
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Z>]
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R',*3
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= − = − =
9&*N*&H@* &,%
l
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
!


Bảng 1.4+-. !"1.**56
FR),^$_`O9`#] $9`<9+a\*OR&

 !"!#$
- &%-#-* !#$
Bảng 1.5+-. !"1.56
- &3&*#*)@**!#$ !#$
Bảng 1.6+-. !"1>.
*+,+*+? !"/*
R'b*G,G1-)=0
U&% g&0
U-)K&)%E%
e0A Z>] gD n0A Z>] D e0Ag>] D e0Ag>] cD [g>]A D@ 
= − + − + − + − =
FR),^$_`O9`#] $9`<9+a\*OR&

!"!#$
Phạm vi bảo vệ ở độ cao 8m
Phạm vi bảo vệ ở độ cao 17m
Phạm vi bảo vệ ở độ cao 11m
r=14,625m
r=4,875m
r=5,625m
r=11,25m
AT1 AT2
Bể n ớc
Trạm bơm
cứu hỏa
Nhà
điều khiển

17m
11m
17m
11m 11m 11m
11m 11m
11m
11m
11m 11m 11m 11m 11m
11m 11m 11m 11m 11m
Bể n ớc
Trạm bơm
cứu hỏa
Nhà
điều khiển
Nhà QLVH
TN2
TN1
Bể dầu sự cố
AT1 AT2
8m
1 2 3 4
5
6
7
8
9
10
11
12
13 14

40.56
9<#<I;@'Ap p]peD>A pZpepgD>
AZp[pgpcD%


] Z[>] e>]gA D3 
= + =
9&*KM5)N*&,%
e>]g
g>gA D
c c

3
 
= = =
9<#<I;@'A]pepnp!D>Aepgp!pD>
Agpcpp D%


] g ]Z>geA D3 
= + =

9&*KM5)N*&,%
]Z>ge
e>g A D
c c

3
 
= = =

= = =
s<#<I*A[p]pnD>A]pnp !D*
G,
$:%i*)p*>>%pF>tJ%8%=%K>#
<#<I*0
uKME2EF>*3

A DA DA D8       
= − − −

[

8
9
=
F),*
A D


3 
8
=
s*A[p]pnD3
Z!>] []>cn [!>c
]c>eA D

  
 
+ + + +
= = =

A DA DA D8       
= − − −

[

8
9
=
F),*
A D


3 
8
=
s*Apgp D3
]!>g Z[ Z
]c>Z]A D

  
 
+ + + +
= = =

]c>Z]0A]c>Z] ]!>gDA]c>Z] Z[DA]c>Z] Z D ]Z]>g8 
= − − − =
]!>g0Z[0Z
]>][A D
0]Z]>g


a#H&*


 0 ] e>eg
Z Z

 
= < = =
7
l


>]0 ]0A D e>ccA D
!>c0 ]
 
= − =
a#H&*g


g 0 ] e>eg
Z Z

 
= > = =
7
l
g
g
!>g]0 ]0A D e>!!A D
]

!>c0n
 
= − =
0 !"<=+
qDa#N* &3&*W*)
-=.56;
s4&Ap D3L&*j ]*)&#*j]
9&*N*&H@* &,%
!
]
] g>gA D
g g

  
= − = − =
a#N*&HH&*

!

 0g>g >c
Z Z

 
= < = =
 7
!
c
>]0g>g0A D ]>n]A D
!>c0g>g
 

a#N*&HH&*c

!

c 0[>g n>c
Z Z

 
= < = =
7
!c
c
>]0[>g0A D g>!gA D
!>c0[>g
 
= − =
a#N*&HH&*

!

 0[>g n>c
Z Z

 
= > = =
7
!

!>g]0[>g0A D >gnA D
[>g

a#N*&HH&*c

!

c 0 >Zg c> ]
Z Z

 
= < = =
7
!c
c
>]0 >Zg0A D Z>]eA D
!>c0 >Zg
 
= − =
a#N*&HH&*

!

 0 >Zg c> ]
Z Z

 
= > = =
7


!>g]0 >Zg0A D >!ZA D
 >Zg

r=7,88m
12
r=16,88m
r=6m
AT1 AT2
Bể n ớc
Trạm bơm
cứu hỏa
Nhà
điều khiển
Nhà QLVH
TN2
TN1
Bể dầu sự cố
AT1 AT2
1 2 3 4
5
6
7
8
9
10
11
13 14
18 19 20
15
21 22
16 17
Phạm vi bảo vệ ở độ cao 8m
Phạm vi bảo vệ ở độ cao 17m

35&G)M0FG)
,7)8)N*13KIX%:K',HG
B0
\HGB;35KI:'&%:>KMN*
G*0R5=HGB;G#K',
*#*=%*,)#6)'#0
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