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8/13/2019 Mathcad - Ampacity Calculation
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POWER CABLE AMPACITY
(132 kV)
132 kV, 1200 mm2
In trench sectionIn !! crossin" section
In !#ct $%nk &or crossin" section
Final Ampacity calculation N7144.xmcd 1 22.03.2013
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CO'TE'T(
Variable ata (!eneral) 4
Po)er C%$*e Am+%cit C%*c#*%tions
1. A" #e$i$tance o% "onductor 13
2. ielectric &o$$ per 'nit &ent %or te *n$ulation 1+
3. &o$$ Factor %or ,etallic -creen and -eat 1+
4. "alculation o% ermal #e$i$tance 21
+. "onductor emperature #i$e abo/e te Ambient 2
. "ontinuou$ "urrent "arryin "apacity o% one 132 kV circuit 2
7. #eduction %actor o% one 132 kV "ircuit 2
. -uper po$ition metod to calculate interaction o% ru 132 kV cablecircuit and to exi$tin 400 kV cable circuit$ 3
. #eduction %actor o% interaction o% ru 132 kV cable circuit$ it teto exi$tin 400 kV cable circuit$ +1
Po)er C%$*e Im+e-%nce C%*c#*%tions
1. 5o$iti/e6Neati/e -euence *mpedance 7
2. 8ero *mpedance 7
Final Ampacity calculation N7144.xmcd 2 22.03.2013
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POWER CABLE AMPACITY
CALC.LATIO'(*9" 027 : "*!#9 ;! 1
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"A&9 =59> 132 kV ?&59 cable@ 12$mm@ copper conductor@ lead : 59 $eated /BR.
*N-A&&A*BN 5&A"9> A' A* < '.A.9.
5#BC9"> A' A* 2 6 9A@ #AN-"B N7144
VARIABLE !ATA
A E*ectric%* (stem !%t%
Up_400 400000:= (5a$e to pa$e /oltae@ V)
U
p_132
132000:= (5a$e to pa$e /oltae@ V)
fc 50:= (Freuency@ D)
2. fc:= (Anular %reuency@ D) 314.2=
Iccs_400 63000:= (,ax. eart
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B C%$*e Constr#ction !%t%
n 1:= (Number o% load
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C E*ectric%* Ch%r%cteristics
!
o
15.1 10 6
:= (.". re$i$tance o% te conductor at 20E"@ Bm6m)
coppr 1.7241 10 8
:= (9lectrical re$i$ti/ity o% "opper@ Bm6m) < *9" 027
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Tem+er%t#res %n- Tem+er%t#re Coe&&icients
ma% 90:= (,ax. operatin temperature o% conductor. E")
c1 250:= (,ax. $ort
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T+ic%* Tro#"h cross6sction
132 kV Circ#it
h'cb_tr 1150:= (i$tance %rom round $ur%ace to cable bottom@ mm)
h'1ca_tr h'cb_tr
do
2:= (i$tance %rom round $ur%ace to cable axi$@ mm)
h'1ca_tr 1098=
str 200:= (Axial $pacin o% conductor #@=@ in trenc@ mm)
sctr 2100:= ("enter to "enter di$tance o% cable circuit$ in trenc@ mm)
m_tr 81.5:= (;orkin temperature o% te lead $eat in trou@ E")
Final Ampacity calculation N7144.xmcd 22.03.2013
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I !! Crossin"
132 kV Circ#it
tpip_hdd 15:= (ickne$$ o% 59 duct all@ mm)
dipip_hdd 195:= (*n$ide diameter o% 59 duct@ mm)
dopip_hdd dipip_hdd 2tpip_hdd( )+:= (Butdi$e diamenter o% 59@ mm) dopip_hdd 225=
tbt 50:= (ickne$$ o% bentonite layer around te cable@ mm)
shdd dopip_hdd:= (Axial $pacin o% te conductor$ in $ection@ mm)
*hdd 70001
2
3
3+
dopip_hdd+:= (i$tance %rom road le/el to te tre%oil center@ mm)
*hdd 7242=
m_hdd 80:= (;orkin temperature o% te lead $eat in trou@ E")
Final Ampacity calculation N7144.xmcd 22.03.2013
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7 T+ic%* Ro%- Crossin"
132 kV Circ#it
tpip_rc 10:= (ickne$$ o% 59 duct all@ mm)
dipip_rc 180:= (*n$ide diameter o% 59 duct@ mm)
dopip_rc dipip_rc 2tpip_rc( )+:= (Butdi$e diamenter o% 59@ mm) dopip_rc 200=
tbt 50:= (ickne$$ o% bentonite layer around te cable@ mm)
+,- 1800:= (;idt o% te uct bank@ mm)
,- 550:= (eit o% te uct bank@ mm)
h',- 1225:= (ept o% te uct bank centre@ mm)
/ 3:= (Number o% cable$ o% al% duct bank$)
src
300:= (Axial $pacin o% te conductor$ in road cro$$in@ mm)
Final Ampacity calculation N7144.xmcd 10 22.03.2013
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scrc 2100:= ("enter to "enter di$tance o% cable circuit$ in trenc@ mm)
h'cb_rc 1325:= (i$tance %rom round $ur%ace to cable bottom@ mm)
h'db_rc h'cb_rc
tpip_rc
2+:= (i$tance %rom round $ur%ace to duct bottom@ mm)
h'db_rc 1330=
h'1ca_rc h'cb_rc
do
2:= (i$tance %rom round $ur%ace to cable axi$@ mm)
h'1ca_rc 1273=
h'da_rc h'db_rc
dipip_rc
2:= (i$tance %rom round $ur%ace to duct axi$@ mm)
h'da_rc 1240=
m_rc 80.5:= (;orkin temperature o% te lead $eat in trou@ E")
8 !et%i*s o& +%r%**e* r#nnin" 900 kV C%$*es in Tro#"h (ection
h'400_tr 1100:= (urial dept %rom round $ur%ace to cable bottom@ mm)
,400a_400b_tr 2800:= (Axial di$tance beteen 400 kV and 400 kV "ircuit$@ mm)
,400a_132_tr 2100:= (Axial di$tance beteen 400 kV clo$e$t and 132 kV "ircuit$@ mm)
,400b_132_tr 4900:= (Axial di$tance beteen 400 kV %urte$t and 132 kV "ircuit$@ mm)
400_tr 600:= (Axial di$tance beteen o% te 400 kV circuit$@ mm)
A400 2500:= ("ro$$ $ection o% copper conductor@ mm2)
!A_400_tr 9.7232 10 6
:=(A" re$i$tance o% te conductor@ Bm6m)
1a_tr_400 0.0901:= (&o$$ %actor %or $creen and $eat o% pa$e 1)
1b_tr_400 0.0605:= (&o$$ %actor %or $creen and $eat o% pa$e 2)
1c_tr_400 0.0601:= (&o$$ %actor %or $creen and $eat o% pa$e 3)
+d400 1.08:= (ielectric &o$$e$@ ;6m)
Final Ampacity calculation N7144.xmcd 11 22.03.2013
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I !et%i*s o& +%r%**e* r#nnin" 900 kV C%$*es in !! (ection
h'400_hdd 7500:= (urial dept %rom round $ur%ace to cable bottom@ mm)
do400pip 280:= (ickne$$ o% 59 pipe@mm)
400_hdd do400pip 280=:= (Axial di$tance beteen o% te 400 kV circuit$@ mm)
*400hdd 7000 1
2
3
3+
do400pip+:= (i$tance %rom road le/el to tre%oil center@mm)
hl400 *400hdd 400_hdd
3
3:= (urial dept o% te upmo$t cable$@mm) hl400 7140=
bl400 *400hdd 400_hdd
3
3+:= (urial dept o% te deepe$ cable$@mm) bl400 7463=
,400a_400b_hdd 3000:= (Axial di$tance beteen 400 kV and 400 kV "ircuit$@ mm)
,400a_132_hdd 3000:= (Axial di$tance beteen 400 kV clo$e$t and 132 kV "ircuit$@ mm)
,400b_132_hdd 6000:= (Axial di$tance beteen 400 kV %urte$t and 132 kV "ircuit$@ mm)
!A_400_hdd
9.754 10 6
:=(A" re$i$tance o% te conductor@ Bm6m)
1_hdd_400 0.1:= (&o$$ %actor %or $creen and $eat )
7 !et%i*s o& +%r%**e* r#nnin" 900 kV C%$*es in Ro%- Crossin" (ection
h'400_rc 1350:= (urial dept %rom round $ur%ace to cable bottom@ mm)
,400a_400b_rc 2800:= (Axial di$tance beteen 400 kV and 400 kV "ircuit$@ mm)
,400a_132_rc 2100:= (Axial di$tance beteen 400 kV clo$e$t and 132 kV "ircuit$@ mm)
,400b_132_rc 4900:= (Axial di$tance beteen 400 kV %urte$t and 132 kV "ircuit$@ mm)
400_rc 300:= (Axial di$tance beteen o% te 400 kV circuit$@ mm)
!A_400_rc 9.723 10 6
:=(A" re$i$tance o% te conductor@ Bm6m)
1a_rc_400 0.0899:= (&o$$ %actor %or $creen and $eat o% pa$e 1)
Final Ampacity calculation N7144.xmcd 12 22.03.2013
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1b_rc_400 0.0604:= (&o$$ %actor %or $creen and $eat o% pa$e 2)
1c_rc_400 0.0600:= (&o$$ %actor %or $creen and $eat o% pa$e 3)
1 AC Resist%nce o& Con-#ctor
!C Resist%nce o& Con-#ctor
"coppr# $ 1 c20 20# $+:= (Factor) "copprma%( ) 1.3=
! !o"copprma%( ):= (.". re$i$tance o% conductor at max. operatin temperature@ Bm6m)
! 1.925 10 5
=!20 !o:= (.". #e$i$tance o% condcutor at 20E"@ Bm6m)
!20 1.51 10 5
=
11 C%$*es in tro#"h
111 (kin E&&ect 4%ctor
%s
8 fc
!10
7( ) "s:= (Factor) %s 1.695=
s
%s4
192 0.8%s4
+
:= (-kin e%%ect %actor)s 0.0415=
112 Pro:imit e&&ect &%ctor
%p
8 fc
!10
7"p:= (Factor %or conduit$)
%p 1.554=
ps# $
%p4
192 0.8%p4
+
dc
s
2
0.312
dc
s
2
1.18
192 0.8 %p( )4
+
%p( )4
0.27 192 0.8 %p( )4
+ ++
:=
pstr( ) 0.006=
113 AC Resist%nce o& the Con-#ctor
!cac_tr ! 1 s+ ps tr( )+( ):= (A.". re$i$tance o% conductor at max. operatin temperature @ Bm6m)
!cac_tr 2.017 10 5
=
Final Ampacity calculation N7144.xmcd 13 22.03.2013
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!cac_hdd ! 1 s+ pshdd( )+( ):=
!cac_tr20 !20 1 s+ ps tr( )+( ):= (A.". re$itance o% condcutor at 20E" temperature@ Bm6m)
!c
ac_tr20
1.6 10 5
=
12 C%$*es in !!
121 (kin e&&ect &%ctor
s 0.0415=
122 Pro:imit e&&ect &%ctor
pshdd( ) 0.00469=
123 AC Resist%nce o& the Con-#ctor
(A.". re$i$tance o% conductor at max. operatin temperature@
Bm6m)
!cac_hdd
2.014 10 5
=
!cac_hdd20 !20 1 s+ pshdd( )+( ):= (A.". re$i$tance o% conductor at 20E" temperature@ Bm6m)
!cac_hdd20 1.6 10 5
=
13 C%$*es in !#ct B%nk %t Ro%- crossin"
131 (kin e&&ect &%ctor
s 0.0415=
132 Pro:imit e&&ect &%ctor
psrc( ) 0.00263=
133 AC Resist%nce o& the con-#ctor
!cac_rc ! 1 s+ psrc( )+( ):= (A.". re$i$tance o% conductor at max. operatin temperature@ Bm6mm)
!c
ac_rc
2.01 10 5
=
Final Ampacity calculation N7144.xmcd 14 22.03.2013
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!cac_rc20 !20 1 s+ psrc( )+( ):= (A.". re$i$tance o% conductor at 20E" temperature@ Bm6m)
!c
ac_rc20
1.6 10 5
=
2 !ie*ectric Loss +er .nit Len"th &or the Ins#*%tion
p
18. lndin
dc1
10 9
:= ("apacitance o% eac pa$e aain$t te $creen $urroundin@ F6m6pa$e)
268.7 10 12
=
Uo
Up_132
3:= (5a$e to neutral /oltae@ V)
Uo 76.2 103
=
Ic Uo 103
:= ("arin current per conductor@ A6km)
Ic 6.43=
+d Uo2
tan # $:= (ielectric lo$$e$ per unit lent per pa$e@ ;6m)
+d 0.49=
3 Loss 4%ctor &or the Met%**ic (creen %n- (he%th
(1) Equivalent Resistance of Lead Sheath
"lad m( ) 1 m 20( ) lad+:= (Factor)
"lad20 1.05:=
!slad m( )lad
Alad
"lad m( ):= (.". re$i$tance o% te lead $eat at teta E"@ Bm6m)
lad
Alad
"lad20# $ 208.39 10 6
=(,ax. .". metallic $eat re$i$tance at 20E"@ Bm6m)
(2) General
m m( )
!slad m( )
10
7:=
s m( ) lad"lad m( ):= (9lectrical re$i$ti/ity o% te lead $eat at $creen temperature)
1 m( ) 4
107
( )
s
m( )
:=
Final Ampacity calculation N7144.xmcd 1+ 22.03.2013
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's m( ) 1:= (Note < For lead $eat cable$ $ can be take a$ unity and1ts( )
4
12 1012
can be nelected < *9" 027
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1flat_cbc ms, !ac,( ) 1flat_cms, !ac,( )0.004:= (;ere lent$ o% minor $ection$ are unkno@ multiply by %actor o% 0.004)
/2 Circ#*%tin" *oss c%*c#*%tion &or three sin"*e6core c%$*es in tre&oi* &orm%tion $on-e- %t $oth en-s /C*%#se 231
trfs# $ 2.10 7.
ln2.s
dlad
:=
(#eactance o% -eat per unit lent@ Bm6m)
trfshdd( ) 1.006 10 4
=
1_trf ms, !ac,( )!slad m( )
!ac
1
1
!slad m( )trfs# $
2
+
:=
1_trf_cb ms, !ac,( ) 1_trf ms, !ac,( )0.004:= (;ere lent$ o% minor $ection$ are unkno@ multiply by %actor o% 0.004)
32 E-- C#rrent Loss 4%ctor /C*23;1 o& IEC ;02
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1a ms,( ) 0.86 m m( )3.08
dlad
2s
1.4m m( ) 0.7+
:=
2a ms,( ) 0:=
1a ms, !ac,( )!slad m( )
!ac
's m( ) 0a ms,( ) 1 1a ms,( )+ 2a ms,( )+( ):=
$ O#ter c%$*e *e%-in" +h%se
0b ms,( ) 1.5m m( )
2
1 m m( )2
+
dlad
2s
2
:= (9ddy current lo$$ %actor %or cable$ in trou)
1b ms,( ) 4.7 m m( )0.7
dlad
2s
0.16m m( ) 2+
:=
2b ms,( ) 21 m m( )3.3
dlad
2s
1.47m m( ) 5.06+
:=
1b ms, !ac,( )!slad m( )
!ac
's m( ) 0b ms,( ) 1 1b ms,( )+ 2b ms,( )+( ):=
C O#ter c%$*e *%""in" +h%se
0c ms,( ) 1.5m m( )
2
1 m m( )2
+
dlad
2s
2
:= (9ddy current lo$$ %actor %or cable$ in trou)
1c ms,( )0.74 m m( ) 2+( )m m( )
0.5
2 m m( ) 0.3( )2
+
dlad
2s
m m( ) 1+
:=
2c ms,( ) 0.92 m m( )3.7 dlad
2s
m m( ) 2+
:=
1c ms, !ac,( )!slad m( )
!ac
's m( ) 0c ms,( ) 1 1c ms,( )+ 2c ms,( )+( ):=
Final Ampacity calculation N7144.xmcd 1 22.03.2013
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33 Loss 4%ctor &or (he%th %n- screen
331 Loss 4%ctor &or (he%th in tro#"h
!slad ms( ) 258.403 10 6
= (.". re$i$tance o% te lead $eat at teta E"@ Bm6m)
1flat_cba ms str, !cac_tr,( ) 0.0043= ("irculatin current lo$$ %actor on lead $eat o% centre cable)
1flat_cbb ms str, !cac_tr,( ) 0.0095= ("irculatin current lo$$ %actor on lead $eat o% outer leadin cable)
1flat_cbc ms str, !cac_tr,( ) 0.0095= ("irculatin current lo$$ %actor on lead $eat o% outer lain cable)
1a msstr, !cac_tr,( ) 0.0577= (9ddy current lo$$ %actor on lead $eat o% centre cable)
1b ms str, !cac_tr,( ) 0.0152= (9ddy current lo$$ %actor on lead $eat o% outer cable leadin pa$e)
1c msstr, !cac_tr,( ) 0.0152= (9ddy current lo$$ %actor on lead $eat o% outer cable lain pa$e)
1a_trms, !ac,( ) 1flat_cba ms, !ac,( ) 1a ms, !ac,( )+:=(&o$$ %actor %or metallic $creen$6$eat %or cable$ in trou@ pa$e 1)
1a_trmsstr, !cac_tr,( ) 0.0621=
1b_trms, !ac,( ) 1flat_cbb ms, !ac,( ) 1b ms, !ac,( )+:=
(&o$$ %actor %or metallic $creen$6$eat %or cable$ in trou@ pa$e 2)
1b_trms str, !cac_tr,( ) 0.0247=
1c_tr
m
s, !ac
,
( )
1flat_cbc
ms, !
ac,
( )
1c
ms, !
ac,
( )+:=
(&o$$ %actor %or metallic $creen$6$eat %or cable$ in trou@ pa$e 3)
1c_trmsstr, !cac_tr,( ) 0.0247=
1_tr 1a_trmsstr, !cac_tr,( ) 0.0621=:= (&o$$ %actor u$ed %or current ratin calculation)
Final Ampacity calculation N7144.xmcd 1 22.03.2013
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332 Loss 4%ctor &or (he%th %n- (creen in !!
!slad ms( ) 258.4 10 6= (.". re$i$tance o% te lead $eat at teta E"@ Bm6m)
1_trf_cb msshdd, !cac_hdd,( ) 0.0067= ("irculatin current lo$$ %actor)
1_t msshdd, !cac_hdd,( ) 0.0233= (9ddy current lo$$ %actor on lead $eat o% centre cable)
1_hddf ms, !ac,( ) 1_trf_cb ms, !ac,( ) 1_t ms, !ac,( )+:=
(&o$$ %actor %or metallic $creen6$eat %or tre%oil %ormation)
1_hddfmsshdd, !cac_hdd,( ) 0.03=
1_hdd 1_hddf ms shdd, !cac_hdd,( ) 0.03=:= (&o$$ %actor u$ed %or current ratin calculation)
333 Loss 4%ctor &or (he%th %n- (creen in Ro%- crossin"
!slad ms( ) 258.403 10 6
= (.". re$i$tance o% te lead $eat at teta E"@ Bm6m)
1flat_cba ms src, !cac_rc,( ) 0.0072= ("irculatin current lo$$ %actor on lead $eat o% centre cable)
1flat_cbb ms src, !cac_rc,( ) 0.0127= ("irculatin current lo$$ %actor on lead $eat o% outer leadin cable)
1flat_cbc ms src, !cac_rc,( ) 0.0127= ("irculatin current lo$$ %actor on lead $eat o% outer lain cable)
1a mssrc, !cac_rc,( ) 0.0257= (9ddy current lo$$ %actor on lead $eat o% centre cable)
1b ms src, !cac_rc,( ) 6.584 10 3
= (9ddy current lo$$ %actor on lead $eat o% outer cable leadin pa$e)
1c mssrc, !cac_rc,( ) 0.0066= (9ddy current lo$$ %actor on lead $eat o% outer cable lain pa$e)
1a_rc ms, !ac,( ) 1flat_cba ms, !ac,( ) 1a ms, !ac,( )+:=
(&o$$ %actor %or metallic $creen$6$eat %or cable$ in trou@ pa$e 1)
1a_rc mssrc, !cac_rc,( ) 0.0329=
Final Ampacity calculation N7144.xmcd 20 22.03.2013
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1b_rc ms, !ac,( ) 1flat_cbb ms, !ac,( ) 1b ms, !ac,( )+:=
(&o$$ %actor %or metallic $creen$6$eat %or cable$ in trou@ pa$e 2)1b_rc ms src, !cac_rc,( ) 0.0193=
1c_rc ms, !ac,( ) 1flat_cbc ms, !ac,( ) 1c ms, !ac,( )+:=
(&o$$ %actor %or metallic $creen$6$eat %or cable$ in trou@ pa$e 3)
1c_rc mssrc, !cac_rc,( ) 0.0193=
1_rc
1a_rc
ms
s
rc
, !cac_rc
,
( ) 0.0329=:= (&o$$ %actor u$ed %or current ratin calculation)
9 C%*c#*%tion o& Therm%* Resist%nce
91 Therm%* Resist%nce $et)een on con-#ctor %n- she%th, T1/C*2111 o& IEC ;02=16261
911 Therm%* Resist%nce o& $in-er t%+e o5er con-#ctor
10
b
2ln
dc0
dc
:= (ermal re$i$tance beteen one conductor and -6"@ .m6;)
10 0.0375=
912 Therm%* Resist%nce o& (>C screen o5er $in-er t%+e
(ermal re$i$tance beteen one conductor and in$ulation $eat@
.m6;)11
sc
2ln
dc1
dc0
:=
11 0.0247=
913 Therm%* Resist%nce o& ?LPE ins#*%tion
12
%lp
2ln
din
dc1
:= (ermal re$i$tance beteen one conductor and -6"@ .m6;)
12 0.2764=
919 Therm%* Resist%nce o& (>C screen o5er ins#*%tion
(ermal re$i$tance beteen one conductor and metallic $eat@
.m6;)13
sc
2ln
dbst
din
:=
13 0.0171=
Final Ampacity calculation N7144.xmcd 21 22.03.2013
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91@ Therm%* Resist%nce o& (>C Be--in" $e*o) Le%- (he%th
14
b
2 ln
dbcs
dbst
:=(ermal re$i$tance beteen -ellin tape@ .m6;)
14 0.0199=
91; Therm%* Resist%nce one con-#ctor %n- she%th, T1
1 10 11+ 12+ 13+ 14+:= 1 0.3757=
92 Therm%* Resist%nce $et)een (he%th %n- Armo#r, T2
/C* 212 o& IEC ;02
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4trd soil( )soil
2
(1( )1 0.5 1a_trms str, !cac_tr,( ) 1c_trms str, !cac_tr,( )+( )+
1 1b_tr
ms
str
, !cac_tr
,
( )+
( )
ln12h'1ca_tr
str
2
+
+
:=
9xternal ermal #e$i$tance %or current ratin calculation in trou (to u$ed at
denominator o% te %inal %ormula)@ .m6;
4trd st( ) 1.649=
992 C%$*es in !!
For 3 cable$ a/in eual $eat lo$$e$@ laid in tre%oil %ormation and eually $paced apart
9921 Therm%* resist%nce o& $entonite $et)een c%$*e %n- +i+e
41hdd
bntonit
2
ln
dipip_hdd
do
:= (ermal re$i$tance o% bentonite beteen cable and pipe@ .m6;)
41hdd 0.1004=
9922 Therm%* resist%nce o& +i+e m%teri%*
42hdd
p
2
ln
dopip_hdd
dipip_hdd
:=
(ermal re$i$tance o% pipe material@ .m6;) 42hdd 0.0797=
9923 Therm%* resist%nce o& soi*
hl *hdd shdd
3
3:= (urial dept o% te upmo$t cable@ mm) hl 7113=
bl *hdd shdd
3
6+:= (urial dept o% te deep$t cable@ mm) bl 7307=
(land
2.bl
dopip_hdd:= (u i$ calculated it re%erence to te centre line o% te deepe$t duct$(non
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9929 Tot%* Therm%* resist%nce o& c%$*e s#rro#n-in" T9
4hdd soil( ) 41hdd 42hdd+ 4land soil( )+:=
9xternal ermal #e$i$tance %or current ratin calculation in @ .m6;>
4hdd hdd( ) 2.3=
993 C%$*e in -#ct %t ro%- crossin" /re&erence to hottest c%$*e n3
For 3 cable$ a/in uneual $eat lo$$e$@ laid in %lat %ormation and eually $paced apart
9931 Therm%* resist%nce o& $entonite $et)een c%$*e %n- +i+e
41rc
bntonit
2
ln
dipip_rc
do
:= (ermal re$i$tance o% bentonite beteen cable and pipe@ .m6;)
41rc 0.0876=
9932 Therm%* resist%nce o& +i+e m%teri%*
42rc
p&c
2
ln
dopip_rc
di
pip_rc
:= (ermal re$i$tance o% bentonite beteen cable and pipe@ .m6;)
42rc 0.1006=
9933 E:tern%* therm%* resist%nce o& +i+e m%teri%*
%1
2
,-
+,-
2
4
,-
+,-
2
ln1
+,-
2
2
,-2
+
ln,-
2
+:=
rb %
:=(9ui/alent radiu$ o% te duct bank@ mm)
rb 357.897=
(,-
h',-
rb
:=(,- 3.423=
43_corr soil( ) /
2
soil concrt( ) ln (,- (,-
21+
:=
43_corr sr( ) 0.182=
Final Ampacity calculation N7144.xmcd 24 22.03.2013
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9939 Therm%* resist%nce o& c%$*e sorro#n-in" T9
(r
2h'1ca_rc
dopip_rc
:= (r 12.731=
(1r ln (r (r2
1+
:= (1r 3.236=
43m soil( )concrt
2
(1r ln1
2h'1ca_rc
src
2
+
+
43_corr soil( )+:=
9xternal ermal #e$i$tance %or current ratin calculation induct bank (to u$ed at numerator o% te %inal %ormula)@ .m6;
43m sr( ) 1.379=
43rd soil( )concrt
2
(1r
1 0.5 1a_rc ms src, !cac_rc,( ) 1c_rc mssrc, !cac_rc,( )+( )+1 1b_rc mssrc, !cac_rc,( )+( )
ln1
2h'1ca_rc
src
2
+
+
43_corr soil( )+:=
9xternal ermal #e$i$tance %or current ratin calculation in
duct bank (to u$ed at denominator o% te %inal %ormula)@ .m6;
43rd sr( ) 1.384=
993@ Tot%* Therm%* resist%nce o& c%$*e s#rro#n-in" T9
4m soil( ) 41rc 42rc+ 43m soil( )+:=
9xternal termal re$i$tance %or current ratin calculation in duct
bank to be u$ed at numerator o% te %inal %ormula@ .m6;)
4m sr( ) 1.5677=4rc soil( ) 41rc 42rc+ 43rd soil( )+:=
9xternal termal re$i$tance %or current ratin calculation in duct
bank to be u$ed at te denominator o% te %inal %ormula@ .m6;)
4rc sr( ) 1.5723=
Final Ampacity calculation N7144.xmcd 2+ 22.03.2013
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@ Con-#ctor Tem+er%t#re Rise %$o5e the Am$ient Tem+er%t#re
tr
ma% c
'ro(nd:= (emperature ri$e o% te conductor it re$pect to te $urroundin$ o% trou@ E")
tr 50=
hdd ma% c'ro(nd:= (emperature ri$e o% te conductor it re$pect to te $urroundin$ o% @ E")
hdd 50=
rc ma% c'ro(nd:= (emperature ri$e o% te conductor it re$pect to te $urroundin$ o% road cro$$in@ E")
rc 50=
; Contin#o#s C#rrent C%rrin" C%+%cit /A
;1 C%$*es in tro#"h /C#rrent %s % nction o& soi* therm%* resisti5it
soil 0.8 0.9, 2.3..:= (Variable termal re$i$ti/ity o% $oil@ .m6;)
I1trsoil( )tr +d 0.51 n 2 3+ 4trn soil( )+( )+
!cac_tr1 n !cac_tr 1 1_tr+( ) 2+ n !cac_tr 1 1_tr+( ) 3 4trd soil( )+( )+
:=
P1trsoil( ) I1trsoil( )Up_13210 6
3:= (ran$mi$$ion 5oer in ,VA)
I1trsoil( )1237
1183.3
1136
1093.8
1055.9
1021.6
990.3
961.7
935.4
911
888.4
867.3
847.7
829.2
811.9
795.5
= soil
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
= P1trsoil( )282.8
270.5
259.7
250.1
241.4
233.6
226.4
219.9
213.9
208.3
203.1
198.3
193.8
189.6
185.6
181.9
=
I1trst( ) 1055.9= (A)
P1trst( ) 241.4= (,VA)
+c_tr I1trst( )2
!cac_tr 22.485=:= (k;6km)
+s_tr 1_tr+c_tr 1.396=:= (k;6km)
+d_tr +d 0.49=:= (k;6km)
+total_tr +c_tr +s_tr+ +d_tr+ 24.37=:= (k;6km)
Final Ampacity calculation N7144.xmcd 2 22.03.2013
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Final /eri%ication o% te $creen6$eat temperature
fin_tr soil( ) ma% 1 !cac_tr I1trsoil( )2+d
2+
:=
fin_tr st( ) 81.5=
m_tr 81.5=
;2 C%$*es in !! /C#rrent %s % nction o& soi* therm%* resisti5it
soil 0.8 0.9, 2.3..:= (Variable termal re$i$ti/ity o% $oil@ .m6;)
I1hdd soil( )hdd +d 0.51 n 2 3+ 4hdd soil( )+( )+
!cac_hdd1 n !cac_hdd 1 1_hdd+( ) 2+ n !cac_hdd 1 1_hdd+( ) 3 4hdd soil( )+( )+
:=
P1hdd soil( ) I1hdd soil( )Up_13210 6
3:=(ran$mi$$ion 5oer in ,VA)
I1hdd soil( )1018
973
934
898
867
838
812
788
766
746
727
709
693
677
663
649
= soil
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
= P1hdd soil( )232.8
222.5
213.4
205.4
198.1
191.6
185.6
180.1
175.1
170.5
166.1
162.1
158.4
154.8
151.5
148.4
=
I1hdd hdd( ) 933.6= (A)
P1hdd hdd( ) 213.4= (,VA)
+c_hdd I1hdd hdd( )2
!cac_hdd 17.558=:= (k;6km)
+s_hdd 1_hdd+c_hdd 0.527=:= (k;6km)
+d_hdd +d 0.49=:= (k;6km)
+total_hdd +c_hdd +s_hdd+ +d_hdd+ 18.57=:= (k;6km)
Final Ampacity calculation N7144.xmcd 27 22.03.2013
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Final /eri%ication o% te $creen6$eat temperature
fin_hdd soil( ) ma% 1 !cac_hdd I1hdd soil( )2
+d
2+
:=
fin_tr hdd( ) 80.1=
m_hdd 80=
;3 C%$*es in -#cts %t ro%- crossin" /C#rrent %s % nction o& soi* therm%* resisti5it
soil 0.8 0.9, 2.3..:= (Variable termal re$i$ti/ity o% $oil@ .m6;)
I1rc soil( )rc +d 0.51 n 2 3+ 4m soil( )+( )+
!cac_rc1 n !cac_rc 1 1_rc+( ) 2+ n !cac_rc 1 1_rc+( ) 3 4rc soil( )+( )+
:=
P1rc soil( ) I1rc soil( )Up_13210 6
3:=(ran$mi$$ion 5oer in ,VA)
I1rc soil( )1208
1175
1145
1117
1090
1066
1043
1021
1001
982
964
946
930
914
899
885
= soil
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
= P1rc soil( )276.3
268.7
261.8
255.3
249.3
243.7
238.4
233.5
228.8
224.5
220.3
216.4
212.6
209
205.6
202.4
=
I1rc sr( ) 1090= (A)
P1rc sr( ) 249.3= (,VA)
+c_rc I1hdd sr( )2
!cac_rc 15.099=:=
+s_rc 1_rc+c_rc 0.497=:=
+d_rc +d 0.49=:=
+total_rc +c_rc +s_rc+ +d_rc+ 16.09=:=
Final Ampacity calculation N7144.xmcd 2 22.03.2013
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Final /eri%ication o% te $creen6$eat temperature
fin_rc soil( ) ma% 1 !cac_rc I1rc soil( )2
+d
2
+
:=
fin_rc sr( ) 80.9=
m_rc 80.5=
= Re-#ction 4%ctors
=1 R41 C%$*es in tro#"h &or 5%rio#s !e+ths %n- L%in" 6di$tance %rom round $ur%ace to cable axi$
h'ca 600 700, 2000..:= (Variable i$tance$ o% "able$ %rom round $ur%ace@ mm)
(t_!1hr# $2.hr# $
do
:=
(1t_!1hr# $ ln (t_!1hr# $ (t_!1hr# $2
1+
:=
9xternal ermal #e$i$tance %or current ratin calculation in
trou (to u$ed at numerator o% te %inal %ormula)@ .m6;4
trn_!1
soilhr,
( )
soil
2
(
1t_!1hr# $ ln1
2hr
str
2
+
+
:=
4trd_!1 soilhr,( )soil
2
(1t_!1hr# $
1 0.5 1a_trms str, !cac_tr,( ) 1c_trms str, !cac_tr,( )+( )+1 1b_trms str, !cac_tr,( )+( )
ln1
2hr
str
2
+
+
:=
9xternal ermal #e$i$tance %or current ratin calculation in trou (to u$ed at
denominator o% te %inal %ormula)@ .m6;
I1tr_!1 soil hr,( )tr +d 0.51 n 2 3+ 4trn_!1 soil hr,( )+( )+
!cac_tr1 n !cac_tr 1 1_tr+( ) 2+ n !cac_tr 1 1_tr+( ) 3 4trd_!1 soilhr,( )+( )+
:=
P1tr_!1 soil hr,( ) I1tr_!1 soilhr,( )Up_13210 6
3:=(ran$mi$$ion 5oer in ,VA)
!1t soil hr,( )I1tr_!1 soil hr,( )
I1trst( )
:=
Final Ampacity calculation N7144.xmcd 2 22.03.2013
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h'ca
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
= !1t st h'ca,( )1.099
1.071
1.048
1.03
1.014
1
0.988
0.977
0.967
0.958
0.95
0.943
0.936
0.929
0.923
= I1tr_!1 st h'ca,( )1160
1131
1107
1087
1070
1056
1043
1031
1021
1012
1003
995
988
981
975
= P1tr_!1 st h'ca,( )265
259
253
249
245
241
238
236
233
231
229
228
226
224
223
=
600 800 1000 1200 1400 1600 1800 2000220
232.5
245
257.5
270
abl *ain' dpth: mm
7ransmissionPo;r:1 hddh'ca,( )215
210
206
202
199
195
193
190
188
187
186
185
185
185
185
185
185
185
185
185
185
185
185
185
=!>1t hdd h'ca,( )
1.138
1.112
1.089
1.068
1.049
1.032
1.018
1.005
0.996
0.989
0.984
0.98
0.978
0.977
0.976
0.976
0.975
0.975
0.975
0.975
0.975
0.975
0.975
0.975
=
3500 5416.7 7333.3 9250 11166.7 13083.3 150000.97
1
1.04
1.07
1.11
1.14
,pth of cabl circ(it: mm
!d(ction8acto
r:!8>1hdd
!>1t hdd h'ca,( )
h'ca
Final Ampacity calculation N7144.xmcd + 22.03.2013
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D3 R481 C%$*es in -#ct$%nk &or ro%- crossin" &or 5%rio#s !e+ths %n- L%in" )ith inter%ction o&900 kV circ#its
h'ca 750 1000, 3000..:= (Variable i$tance$ o% "able$ axi$ %rom round $ur%ace@ mm)
,"02_"1ahr# $ ,400b_132_rc 400_rc+( )2
hr h'400_rc( )2
+:=(di$tance beteen 02 and 1@ mm)
,"02_"1mahr# $ ,400b_132_rc 400_rc+( )2
hr h'400_rc+( )2
+:=(di$tance beteen 02 and mirror imae 1@ mm)
,"02_"2ahr# $ ,400b_132_rc( )2
hr h'400_rc( )2
+:=(di$tance beteen 02 and 2@ mm)
,"02_"2mahr# $ ,400b_132_rc( )2
hr h'400_rc+( )2
+:=(di$tance beteen 02 and mirror imae 2@ mm)
,"02_"3ahr# $ ,400b_132_rc 400_rc( )2
hr h'400_rc( )2
+:=(di$tance beteen 02 and 3@ mm)
,"02_"3mahr# $ ,400b_132_rc 400_rc( )2
hr h'400_rc+( )2
+:=(di$tance beteen 02 and mirror imae 3@ mm)
,"02_"4ahr# $ ,400a_132_rc 400_rc+( )2
hr h'400_rc( )2
+:=(di$tance beteen 02 and 4@ mm)
,"02_"4mahr# $ ,400a_132_rc 400_rc+( )2
hr h'400_rc+( )2
+:= (di$tance beteen 02 and mirror imae 4@ mm)
,"02_"5ahr# $ ,400a_132_rc( )2
hr h'400_rc( )2
+:=(di$tance beteen 02 and +@ mm)
,"02_"5mahr# $ ,400a_132_rc( )2
hr h'400_rc+( )2
+:=(di$tance beteen 02 and mirror imae +@ mm)
,"02_"6ahr# $ ,400a_132_rc 400_rc( )2
hr h'400_rc( )2
+:=(di$tance beteen 02 and @ mm)
,"02_"6mahr# $ ,400a_132_rc 400_rc( )2
hr h'400_rc+( )2
+:=(di$tance beteen 02 and @ mm)
Final Ampacity calculation N7144.xmcd + 22.03.2013
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I400rca
P400rc1000( )3 400( )
:= ("urrent in te 400 kV circuit a$ a %unction o% te tran$mitted poer@ A)
I
400rca
1155=
+400_arca !A_400_rc 1 1a_rc_400+( ) I400rca2
+d400+:= (9$timated lo$$e$ in te 400 kV pa$e a circuit a$ a %unction o%te tran$mitted poer 5 at 400 kV@ ;6m)
+400_arca 15.209=
+400_brca !A_400_rc 1 1b_rc_400+( ) I400rca2 +d400+:= (9$timated lo$$e$ in te 400 kV pa$e b circuit a$ a %unction o%
te tran$mitted poer 5 at 400 kV@ ;6m)+400_brca 14.827=
+400_crca !A_400_rc 1 1c_rc_400+( ) I400rca2 +d400+:= (9$timated lo$$e$ in te 400 kV pa$e c circuit a$ a %unction o%
te tran$mitted poer 5 at 400 kV@ ;6m)+400_crca 14.822=
(emperature ri$e at te $ur%ace o% cable produced by te poer
o% %urte$t 400 kV circuit and di$$pated in cable 02)"02_"1a soil hr,( )
1
2soil +400_arca ln
,"02_"1mahr# $
,"02_"1ahr# $
:=
(emperature ri$e at te $ur%ace o% cable produced by te poer
o% %urte$t 400 kV circuit and di$$pated in cable 02)"02_"2a soil hr,( )
1
2soil +400_brca ln
,"02_"2mahr# $
,"02_"2ahr# $
:=
(emperature ri$e at te $ur%ace o% cable produced by te poer
o% %urte$t 400 kV circuit and di$$pated in cable 02)"02_"3a soil hr,( )
1
2soil +400_crca ln
,"02_"3mahr# $
,"02_"3ahr# $
:=
(emperature ri$e at te $ur%ace o% cable produced by te poer
o% clo$e$t 400 kV circuit and di$$pated in cable 02)"02_"4a soil hr,( )
1
2soil +400_arca ln
,"02_"4mahr# $
,"02_"4ahr# $
:=
(emperature ri$e at te $ur%ace o% cable produced by te poer
o% clo$e$t 400 kV circuit and di$$pated in cable 02)"02_"5a soil hr,( )
1
2soil +400_brca ln
,"02_"5mahr# $
,"02_"5ahr# $
:=
(emperature ri$e at te $ur%ace o% cable produced by te poer
o% clo$e$t 400 kV circuit and di$$pated in cable 02)"02_"6a soil hr,( )
1
2soil +400_crca ln
,"02_"6mahr# $
,"02_"6ahr# $
:=
Prca soilhr,( ) "02_"1a soil hr,( ) "02_"2a soil hr,( )+ "02_"3a soil hr,( )+ "02_"4a soil hr,( )+"02_"5a soilhr,( ) "02_"6a soil hr,( )++
...
:=
(otal ri$e abo/e ambient temperature at te $ur%ace o% te 02 cable@ o$e ratin i$ bein determined@ cau$ed by te
poer di$$pated by te oter cable$ in roup)
h',-_!)1hr# $ hr do
2+ tpip_rc+ dopip_rc 200
,-+:=
Final Ampacity calculation N7144.xmcd 0 22.03.2013
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(,-_!)1hr# $
h',-_!)1hr# $
rb
:=
4r_corr_!)1 soilhr,( ) /
2
soil concrt( ) ln (,-_!)1hr# $ (,-_!)1hr# $
2 1+
:=
(rc_!)1hr# $2hr
dopip_rc
:=
(1rc_!)1hr# $ ln (rc_!)1hr# $ (rc_!)1hr# $2
1+
:=
43rn_!)1 soil hr,( )concrt
2
(1rc_!)1hr# $ ln1
2hr
str
2
+
+
4r_corr_!)1 soilhr,( )+:=
9xternal ermal #e$i$tance %or current ratin calculation in
duct bank (to u$ed at numerator o% te %inal %ormula)@ .m6;
43rd_!)1 soil hr,( )concrt
2
(1rc_!)1hr# $
1 0.5 1a_rc ms src, !cac_rc,( ) 1c_rc mssrc, !cac_rc,( )+( )+1 1b_rc mssrc, !cac_rc,( )+( )
ln1
2hr
str
2
+
+
4r_corr_!)1 soilhr,( )+
...:=
9xternal ermal #e$i$tance %or current ratin calculation in duct bank (to u$ed at
denominator o% te %inal %ormula)@ .m6;
4rn_!)1 soilhr,( ) 41rc 42rc+ 43rn_!)1 soilhr,( )+:= 9xternal ermal #e$i$tance %or current ratin calculation induct bank (to u$ed at numerator o% te %inal %ormula)@ .m6;
4rd_!)1 soilhr,( ) 41rc 42rc+ 43rd_!)1 soilhr,( )+:= 9xternal ermal #e$i$tance %or current ratin calculation induct bank (to u$ed at denominator o% te %inal %ormula)@ .m6;
I1rc_!)1 soilhr,( )rc Prca soilhr,( )( ) +d 0.51 n 2 3+ 4rn_!)1 soilhr,( )+( )+
!cac_rc1 n !cac_rc 1 1_rc+( ) 2+ n !cac_rc 1 1_rc+( ) 3 4rd_!)1 soil hr,( )+( )+
:=
P1rc_!)1 soil hr,( ) I1rc_!)1 soil hr,( )Up_13210 6
3:=(ran$mi$$ion 5oer in ,VA)
!)1t soilhr,( )I1rc_!)1 soil hr,( )
I1132_400rc soil P400rc,( )
:=
Final Ampacity calculation N7144.xmcd 1 22.03.2013
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h'ca
750
1000
1250
1500
1750
2000
2250
2500
2750
3000
= Prca sr h'ca,( )3.337
4.282
5.094
5.76
6.274
6.648
6.898
7.047
7.115
7.122
= !)1t sr h'ca,( )1.062
1.007
0.967
0.937
0.913
0.894
0.879
0.867
0.857
0.848
= I1rc_!)1 sr h'ca,( )1095
1039
998
966
942
923
907
894
884
875
= P1rc_!)1 sr h'ca,( )250
237
228
221
215
211
207
204
202
200
=
750 1125 1500 1875 2250 2625 30000.84
0.89
0.94
1
1.05
1.1
,pth of cabl circ(it: mm
!d(ction8actor:!8)1rc
!)1t sr h'ca,( )
h'ca
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D9 R4?2 C%$*es in tro#"h &or 5%rio#s soi* resisti5iti )ith inter%cion o& 900 kV circ#its
soil 0.8 0.9, 2.3..:= (Variable termal re$i$ti/ity o% $oil@ .m6;)
I1tr_!2 soilP,( )tr Ptr soilP,( )( ) +d 0.51 n 2 3+ 4trn soil( )+( )+
!cac_tr1 n !cac_tr 1 1_tr+( ) 2+ n !cac_tr 1 1_tr+( ) 3 4trd soil( )+( )+
:=
P1tr_!2 soil P,( )I1tr_!2 soil P,( ) 3 132( )
1000:=
!2t soil P,( )I1tr_!2 soil P,( )I1132_400tr st P,( )
:= (#eduction Factor due to 400 kV circuit)
soil
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
= !2t soil P400tr,( )1.208
1.147
1.093
1.044
1
0.96
0.923
0.889
0.857
0.828
0.8
0.774
0.75
0.727
0.705
0.684
= I1tr_!2 soilP400tr,( )1171
1112
1059
1012
969
930
895
862
831
802
776
750
727
704
683
663
= P1tr_!2 soil P400tr,( )268
254
242
231
222
213
205
197
190
183
177
172
166
161
156
151
=
Final Ampacity calculation N7144.xmcd 3 22.03.2013
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0.8 1.1 1.3 1.6 1.8 2.1 2.30.6
0.7
0.8
1
1.1
1.2
oil thrmal rsisti&it: ?.m@+
!d(ction8actor:!82tr
!2t soil P400tr,( )
soil
D@ R4Y2 C%$*es in !! crossin" &or 5%rio#s soi* resisti5it )ith inter%cion o& 900 kV circ#its
soil 0.8 0.9, 2.3..:= (Variable termal re$i$ti/ity o% $oil@ .m6;)
I1hdd_!>2 soilP,( )hdd Phdd soil P,( )( ) +d 0.51 n 2 3+ 4hdd soil( )+( )+
!c
ac_hdd
1 n !cac_hdd
1 1_hdd
+
( ) 2+ n !c
ac_hdd
1 1_hdd
+
( ) 3 4
hdd
soil( )+
( )+
:=
P1hdd_!>2 soil P,( )I1132_400hdd soilP,( ) 3 132( )
1000:=
!>2t soilP,( )I1hdd_!>2 soil P,( )
I1132_400hdd hddP,( ):= (#eduction Factor due to 400 kV circuit)
Final Ampacity calculation N7144.xmcd 4 22.03.2013
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soil
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.81.9
2
2.1
2.2
2.3
= !>2t soil P400hdd,( )1.12
1.057
1
0.949
0.902
0.859
0.819
0.782
0.748
0.715
0.6850.656
0.628
0.601
0.576
0.551
= I1hdd_!>2 soil P400hdd,( )927
875
828
785
747
711
678
648
619
592
567543
520
498
476
456
= P1hdd_!>2 soilP400hdd,( )212
200
189
180
171
163
155
148
142
135
130124
119
114
109
104
=
0.8 1.1 1.3 1.6 1.8 2.1 2.30.6
0.7
0.8
0.9
1
1.1
oil thrmal rsisti&it: ?.m@+
!d(ction8actor:!8>2hdd
!>2t soil P400hdd,( )
soil
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D; R482 C%$*es in !#ct $%nk &or crossin" &or 5%rio#s soi* resisti5it )ith inter%cion o& 900 kV
circ#its
soil 0.8 0.9, 2.3..:= (Variable termal re$i$ti/ity o% $oil@ .m6;)
I1rc_!)2 soilP,( )rc Prc soil P,( )( ) +d 0.51 n 2 3+ 4m soil( )+( )+
!cac_rc1 n !cac_rc 1 1_rc+( ) 2+ n !cac_rc 1 1_rc+( ) 3 4rc soil( )+( )+
:=
P1rc_!)2 soil P,( )I1132_400rc soil P,( ) 3 132( )
1000:=
!)2t soilP,( )I1rc_!)2 soil P,( )I1132_400rc sr P,( )
:= (#eduction Factor due to 400 kV circuit)
soil0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
= !)2t
soilP
400rc,
( )1.131.094
1.06
1.029
1
0.973
0.947
0.923
0.899
0.878
0.857
0.837
0.818
0.8
0.783
0.766
= I1rc_!)2
soil
P400rc
,
( )11651128
1094
1062
1032
1003
977
952
928
905
884
863
844
825
807
790
= P1rc_!)2
soil
P400rc
,
( )266258
250
243
236
229
223
218
212
207
202
197
193
189
185
181
=
Final Ampacity calculation N7144.xmcd 22.03.2013
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0.8 1.1 1.3 1.6 1.8 2.1 2.30.76
0.83
0.91
0.98
1.06
1.13
oil thrmal rsisti&it: ?.m@+
!d
(ction8actor:!8)2rc
!)2t soil P400rc,( )
soil
D> R4?3 C%$*es in tro#"h &or 5%rio#s soi* tem+er%t#res )ith inter%cion o& 900 kV circ#its
'ro(nd 30 31, 50..:=
!3 'ro(nd( ) ma% 'ro(nd:=
I1tr_!3 soilP, 'ro(nd,( )!3 'ro(nd( ) Ptr soil P,( )( ) +d 0.51 n 2 3+ 4trn soil( )+( )+
!cac_tr
1 n !cac_tr
1 1_tr
+
( ) 2+ n !c
ac_tr 1
1_tr+
( ) 3 4
trd
soil( )+
( )+
:=
P1tr_!3 soil P, 'ro(nd,( )I1tr_!3 soil P, 'ro(nd,( ) 3 132( )
1000:=
!3t soil P, 'ro(nd,( )I1tr_!3 soilP, 'ro(nd,( )
I1132_400tr soil P,( ):= (#eduction Factor due to 400 kV circuit)
Final Ampacity calculation N7144.xmcd 7 22.03.2013
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'ro(nd
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
= !3t st P400tr, 'ro(nd,( )1.114
1.103
1.092
1.081
1.07
1.059
1.047
1.036
1.024
1.012
1
0.988
0.976
0.963
0.95
0.938
0.925
0.911
0.898
0.885
0.871
= I1tr_!3 st P400tr, 'ro(nd,( )1080
1070
1059
1048
1037
1026
1015
1004
992
981
969
957
946
933
921
909
896
883
870
857
844
= P1tr_!3 st P400tr, 'ro(nd,( )247
245
242
240
237
235
232
229
227
224
222
219
216
213
211
208
205
202
199
196
193
=
30 33.3 36.7 40 43.3 46.7 500.87
0.92
0.97
1.02
1.07
1.12
oil mprat(r: ?
!d(ctio
n8actor:!83tr
!3t st P400tr, 'ro(nd,( )
'ro(nd
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D< R4Y3 C%$*es in !! crossin" &or 5%rio#s soi* tem+er%t#res )ith inter%cion o& 900 kV circ#its
'ro(nd
30 31, 50..:=
!>3 'ro(nd( ) ma% 'ro(nd:=
'ro(nd 30 31, 50..:=I1hdd_!>3 soilP, 'ro(nd,( )!>3 'ro(nd( ) Phdd soilP,( )( ) +d 0.51 n 2 3+ 4hdd soil( )+( )+
!cac_hdd1 n !cac_hdd 1 1_hdd+( ) 2+ n !cac_hdd 1 1_hdd+( ) 3 4hdd soil( )+( )+
:=
P1hdd_!>3 soil P, 'ro(nd,( )I1hdd_!>3 soil P, 'ro(nd,( ) 3 132( )
1000
:=
!>3t soilP, 'ro(nd,( )I1hdd_!>3 soil P, 'ro(nd,( )
I1132_400hdd soil P,( ):= (#eduction Factor due to 400 kV circuit)
'ro(nd
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
= !>3t hddP400hdd, 'ro(nd,( )1.123
1.111
1.099
1.087
1.075
1.063
1.051
1.038
1.026
1.013
1
0.987
0.974
0.96
0.946
0.932
0.918
0.904
0.89
0.875
0.86
= I1hdd_!>3 hdd P400hdd, 'ro(nd,( )929
920
910
900
890
880
870
859
849
838
828
817
806
795
783
772
760
748
736
724
712
=P1hdd_!>3 hddP400hdd, 'ro(nd,( )212
210
208
206
204
201
199
196
194
192
189
187
184
182
179
176
174
171
168
166
163
Final Ampacity calculation N7144.xmcd 22.03.2013
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30 33.3 36.7 40 43.3 46.7 500.86
0.91
0.96
1.02
1.07
1.12
oil mprat(r: ?
!d(ction8actor:!8>3h
dd
!>3t hdd P400hdd, 'ro(nd,( )
'ro(nd
DD R483 C%$*es in !#ct $%nk &or crossin" &or 5%rio#s soi* tem+er%t#res )ith inter%cion o& 900kV circ#its
'ro(nd 30 31, 50..:=
!)3 'ro(nd( ) ma% 'ro(nd:=
I1rc_!)3 soilP, 'ro(nd,( )!)3 'ro(nd( ) Prc soil P,( )( ) +d 0.51 n 2 3+ 4m soil( )+( )+
!cac_rc1 n !cac_rc 1 1_rc+( ) 2+ n !cac_rc 1 1_rc+( ) 3 4rc soil( )+( )+
:=
P1rc_!)3 soil P, 'ro(nd,( )I1rc_!)3 soilP, 'ro(nd,( ) 3 132( )
1000:=
!)3t soilP, 'ro(nd,( )
I1rc_!)3 soil P, 'ro(nd,( )I1132_400rc soil P,( ):= (#eduction Factor due to 400 kV circuit)
Final Ampacity calculation N7144.xmcd 70 22.03.2013
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'ro(nd
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
= !)3t sr P400rc, 'ro(nd,( )1.108
1.098
1.087
1.077
1.066
1.055
1.045
1.034
1.022
1.011
1
0.989
0.977
0.965
0.953
0.941
0.929
0.917
0.904
0.892
0.879
= I1rc_!)3 sr P400rc, 'ro(nd,( )1143
1132
1122
1111
1100
1089
1078
1066
1055
1043
1032
1020
1008
996
984
971
959
946
933
920
907
= P1rc_!)3 sr P400rc, 'ro(nd,( )261
259
256
254
251
249
246
244
241
239
236
233
230
228
225
222
219
216
213
210
207
=
30 33.3 36.7 40 43.3 46.7 500.87
0.92
0.97
1.02
1.07
1.12
oil mprat(r: ?
!d(ction8actor:!8>3hdd
!>3t hdd P400hdd, 'ro(nd,( )
'ro(nd
Final Ampacity calculation N7144.xmcd 71 22.03.2013
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D10 R4?9 C%$*es in tro#"h &or 5%rio#s c%$*e se+%r%tion )ith inter%cion o& 900 kV circ#its
sca 200 250, 600..:=
,%02_%1bsca( ) ,400b_132_tr sca+( )2
h'1ca_tr h'400_tr( )2
+:=(di$tance beteen ?02 and ?1@ mm)
,%02_%1mbsca( ) ,400b_132_tr sca+( )2
h'1ca_tr h'400_tr+( )2
+:=(di$tance beteen ?02 and mirror imae ?1@ mm)
,%02_%2bsca( ) ,400b_132_tr( )2
h'1ca_tr h'400_tr( )2
+:=(di$tance beteen ?02 and ?2@ mm)
,%02_%2mbsca( ) ,400b_132_tr( )2
h'1ca_tr h'400_tr+( )2
+:=(di$tance beteen ?02 and mirror imae ?2@ mm)
,%02_%3bsca( ) ,400b_132_tr sca( )2
h'1ca_tr h'400_tr( )2
+:=(di$tance beteen ?02 and ?3@ mm)
,%02_%3mbsca( ) ,400b_132_tr sca( )2
h'1ca_tr h'400_tr+( )2
+:=(di$tance beteen ?02 and mirror imae ?3@ mm)
,%02_%4bsca( ) ,400a_132_tr sca+( )2
h'1ca_tr h'400_tr( )2
+:=(di$tance beteen ?02 and ?4@ mm)
,%02_%4mbsca( ) ,400a_132_tr sca+( )2
h'1ca_tr h'400_tr+( )2
+:=(di$tance beteen ?02 and mirror imae ?4@ mm)
,%02_%5bsca( ) ,400a_132_tr( )2
h'1ca_tr h'400_tr( )2
+:=(di$tance beteen ?02 and ?+@ mm)
,%02_%5mbsca( ) ,400a_132_tr( )2
h'1ca_tr h'400_tr+( )2
+:=(di$tance beteen ?02 and mirror imae ?+@ mm)
,%02_%6bsca( ) ,400a_132_tr sca( )2
h'1ca_tr h'400_tr( )2
+:=(di$tance beteen ?02 and ?@ mm)
,%02_%6mbsca( ) ,400a_132_tr sca( )2
h'1ca_tr h'400_tr+( )2
+:=(di$tance beteen ?02 and ?@ mm)
Final Ampacity calculation N7144.xmcd 72 22.03.2013
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POWER CABLEIMPE!A'CE
CALC.LATIO'(
Final Ampacity calculation N7144.xmcd 7+ 22.03.2013
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V%ri%$*e !%t%
) 0.05:= -el% impedance %actor
1
%p)
0.2
:= Factor %or calculation conductor mean $el% eometric di$tance
0.779=
r