TELKOM
NIKA Indonesia
n
Journal of
Electrical En
gineering
Vol.12, No.7, July 201
4, pp
. 5003 ~ 50
1
0
DOI: 10.115
9
1
/telkomni
ka.
v
12i7.425
9
5003
Re
cei
v
ed Au
gust 29, 20
13
; Revi
sed Ma
rch 1
5
, 2014;
Acce
pted Ma
rch 2
6
, 2014
Three-Dimensional Thermal Analysis of Three-Phase
Enclosed GIS Bus Bars
Li Hongtao, Shu Naiqiu, Li Ling*
Schoo
l of Elect
r
ical En
gin
eeri
ng, W
uhan U
n
i
v
ersit
y
No.8, Don
g
h
u
n
an Ro
ad, Ho
ng
shan D
i
strict, W
uhan 4
3
0
072
, China
*Corres
p
o
ndi
n
g
author, e-ma
i
l
: 5pro@
163.co
m
A
b
st
r
a
ct
T
he a
m
pacity
of GIS bus
bar
s is l
i
m
ited
by
the
max
i
mu
m oper
ation
te
mp
erat
ure
of the
contacts
.
T
h
is pa
per
e
m
ploys th
e co
up
l
ed e
ddy c
u
rre
n
t, fluid a
nd th
er
ma
l fin
i
te-el
e
ment
meth
od (F
EM) to solv
e the
three-d
i
mens
io
nal (
3
-D)
he
at transfer
prob
l
e
m in
a
three
-
phas
e e
n
cl
os
ed GIS b
u
s b
a
r. T
he c
onta
c
t
resistanc
e is c
onsi
dere
d
a
n
d
descri
b
e
d
as
a resist
or
bet
w
een the
con
ductor
and
the
contact fin
ger
. I
n
order to
avoi
d
convectiv
e
bo
u
ndary c
ond
itio
n on th
e t
ank
surface w
h
ich
i
s
not easy to
a
pply, the
a
m
bi
ent
air is
i
n
trod
uce
d
i
n
to th
e s
o
luti
on r
egi
on. T
h
e
temp
eratur
e
de
pen
de
nt ther
mal
prop
erties
of
SF
6
gas an
d a
i
r
are co
nsid
ere
d
.
T
he temper
atures ca
lcul
ated
by pro
pos
ed
mo
de
l are
foun
d to b
e
in
go
o
d
agr
ee
ment w
i
t
h
the exper
i
m
ent
al data of a 1
2
6
kV thr
ee-ph
a
s
e encl
o
se
d bu
s bar prototyp
e
.
Ke
y
w
ords
: GIS bus bar, cont
act resistance,
finite-e
le
me
nt meth
od (F
EM), temp
erature ri
se
Copy
right
©
2014 In
stitu
t
e o
f
Ad
van
ced
En
g
i
n
eerin
g and
Scien
ce. All
rig
h
t
s reser
ve
d
.
1. Introduc
tion
Gas in
sulate
d
switchgea
r (GIS) is one o
f
t
he paramo
unt comp
one
nts
in power
system
s.
Once failures happ
en, hu
g
e
metro
polita
n
are
a
s
will
suffer the lo
ss
of power
sup
p
ly, affecting
the
reliability of
power sy
stem an
d leadi
ng to large
economi
c
lo
ss and negative social
im
pact.
Overhe
at cau
s
ed
by co
nta
c
t deg
rad
a
tio
n
is o
ne of
the mos
t
frequent failures
in
GIS. The contac
t
resi
stan
ce b
e
c
ome
s
la
rge
r
than normal value a
fter con
t
act degradati
on occu
rs, which in
crea
se
s
the co
ntact t
e
mpe
r
ature a
nd will
wo
rse
n
the
cont
a
c
t
con
d
ition.
Contact d
e
g
r
a
dation i
s
a
self-
accele
rated
p
r
ocess th
at a
fter a lo
ng
pe
riod
of
g
r
ad
u
a
l
in
cre
a
si
ng cont
a
c
t
resi
st
anc
e
e
s
calat
e
s
rapidly,
cau
s
i
ng lo
cal
melti
ng a
nd finally
leadin
g
to
short
circuit fa
ilure [1
-3]. Th
us, in
order to
avoid cata
strophi
c fault, knowl
edge
of the temperature ri
se in
GI
S bus ba
r is
quite ne
ce
ssary
after it has be
en put into se
rvice.
Over th
e yea
r
s,
su
bsta
ntia
l efforts have
bee
n d
e
vote
d to the
the
r
mal mo
delin
g
of GIS
bus ba
rs. Model
s based
on cou
p
led t
w
o-dime
nsio
nal
(2-D) finite-elem
ent-a
nalytic techni
que
have bee
n propo
sed to p
r
edict temp
era
t
ure ri
se in
G
I
S bus ba
rs [
4
-7]. Three-di
mensi
onal
(3-D)
model
s b
a
se
d on th
e finite-ele
ment
method
(F
EM) a
r
e u
s
ed to
study
the tempe
r
ature
distrib
u
tion o
f
the bus du
ct system
s [8, 9]. Ho
wev
e
r, in these
pape
rs the
convective he
at
transfe
r
coeff
i
cient i
s
a
n
e
m
piri
cal p
a
ra
meter a
nd
h
a
rd to
be
det
ermin
ed e
s
p
e
cially
whe
n
the
st
ru
ct
ur
e inv
e
st
igat
e
d
is
compli
cate
d. More
over, the conta
c
t re
sistan
ce ha
s to be co
nsi
d
e
r
ed
becau
se it always ma
ke
s t
he co
ntact th
e hottest pa
rt in GIS bus ba
r.
In ord
e
r to
ca
lculate
the te
mperature
ri
se in
GIS bu
s
bars, a
3-D fi
nite elem
ent
model i
s
establi
s
h
ed to solve the couple
d
eddy
curre
n
t,
fluid and thermal
probl
em. For
better a
ccu
ra
cy,
the variation
of fluid therm
a
l peop
ertie
s
with te
mpe
r
at
ure i
s
co
nsi
d
ered. Th
e co
ntact re
si
stan
ce
is
de
scri
bed as
a
re
si
stor betwe
en
the con
d
u
c
tor an
d the
conta
c
t. The a
m
bient
air i
s
introdu
ce
d
into the
solut
i
on regio
n
to
avoid the
convecti
ve b
o
unda
ry condi
tion on th
e t
ank surfa
c
e.
The
prop
osed m
o
del is
applie
d on a
126
kV thre
e-
p
h
a
s
e e
n
cl
osed
GIS bus
bar prototype a
n
d
validated by the tempe
r
atu
r
e ri
se expe
ri
ment.
2. Solution Region and Fi
nite Element Mesh
The
solution
regio
n
of the
electroma
gne
tic field an
d t
herm
a
l an
alysis i
s
give
n i
n
Figu
re
1. Becau
s
e
of the multi-scale of different
com
pone
nts in GIS bus ba
r and t
he existen
c
e
of
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 7, July 201
4: 5003 – 50
10
5004
surro
undi
ng
air in the
sol
u
tion re
gion,
the com
put
at
ion scale i
s
i
n
crea
sed. Ap
prop
riate m
e
sh
quality is
ne
ce
ssary to e
n
su
re th
e co
nverge
nce of
iteration
pro
c
e
s
s in
CFD analysi
s
. Th
e
solutio
n
regio
n
is m
e
shed
with 4,92
4,54
0 elem
ents
a
nd 3,96
4,038
node
s. Finit
e
elem
ent m
e
sh
of the air, th
e
con
d
u
c
tor, t
he tan
k
a
nd t
he SF
6
ga
s i
s
sho
w
n i
n
Fi
gure
2. Ta
ble
1 an
d Ta
ble
2
give, resp
ecti
vely, the main geomet
rical
data and mat
e
rial p
r
op
ertie
s
of the analy
z
ed mo
del.
Figure 1. Solution Re
gion
of Therm
a
l Analysi
s
Table 1. Main
Geometry Data of the GIS Bus Bar M
odel (mm
)
Components
Outer
diameter Inner
diamete
rTh
i
ckness
Length
Conductor 85
65
1200
Tank 508
492
1500
Table 2. Mate
rial Data of th
e Model at 0
Ԩ
Components
Densit
y
(
kg/m
3
)
Thermal conducti
vity
(10
-2
W/(
m
K))
Dy
namic viscosit
y
(10
-5
Pa
s)
Specific heat
(J
/(k
g
K))
SF
6
gas
22.82
1.206
1.42
665.18
Air 1.293
2.44
1.72
1005
Conductor 2730
220
–
880
(a) Air
(b)
Con
d
u
c
tor
and tank
(c
)SF
6
gas
Figure 2. Mesh of the Solution Re
gion
3. Three-Dim
e
ntional Edd
y
Current Field Model
Tempe
r
atu
r
e
rise
of the bu
s co
ntact is
h
i
gher
tha
n
th
at of the con
ducto
r be
cau
s
e of the
conta
c
t re
sist
ance. Therefore, t
he po
we
r loss in co
ntact regi
on mu
st be co
nsi
d
e
r
d in the thermal
analysi
s
. Fo
r
the case of
pl
um blo
s
som
conta
c
t, the
contact
s
a
r
e
lo
cated
bet
w
ee
n the i
n
sulato
r
and
con
d
u
c
to
r, whi
c
h
is
eq
ualized to
a resi
stor
R
lo
ca
ted bet
ween
the bul
k
re
sist
ance of
conta
c
t
finger
R
f
and
th
e
c
o
nd
uc
to
r
R
c
, a
s
sho
w
n i
n
Fi
g. 3. The
si
mplification
i
s
de
eme
d
to
be
Evaluation Warning : The document was created with Spire.PDF for Python.
TELKOM
NIKA
ISSN:
2302-4
046
Thre
e-Dim
e
n
s
ion
a
l The
r
m
a
l Analysis of
Three
-
Pha
s
e
Enclosed GI
S Bus Bars
(Li Hon
g
tao)
5005
rea
s
on
able fo
r furthe
r thermal analysi
s
becau
se the
heat
ca
pa
city of the contact is small. In this
pape
r, the co
ntact re
si
stan
ce is
con
s
id
ered to be temp
eratu
r
e de
pe
ndent by [10]:
0
2
(1
)
3
RR
(
1
)
Whe
r
e
R
0
i
s
the co
ntact re
sista
n
ce at ro
om temperature,
α
is the coefficient of resi
stivity,
is
the temperature differen
c
e
.
Figure 3. Sch
e
matic of the
Conta
c
t Re
si
stan
ce
The follo
win
g
assum
p
tion
s are
u
s
ed
in
the an
alysi
s
pro
c
e
ss:
disp
lacem
ent
cu
rrent i
s
negle
c
ted
be
cau
s
e
of th
e
low f
r
eq
uen
cy; the current
flowin
g in
th
e cond
ucto
r i
s
sinu
soi
dal;
the
relu
ctivity is take
n a
s
con
s
tant. Introd
u
c
ing th
e ma
g
netic ve
ctor
potential
A
a
nd the
ele
c
tri
c
scalar p
o
tenti
a
l
Φ
into Maxwell’s equati
on,
the equat
ions governing 3-D eddy current field
can
be written a
s
[8]:
t
1
()
(
)
i
n
V
(
(
)
(
)
)
0
in
V
TT
t
AA
J
A
(
2
)
tse
s
=+
=
(
)
(
)
TT
t
A
JJ
J
J
(
3
)
Whe
r
e
V i
s
th
e whole
soluti
on
regio
n
, V
1
is
the
ed
dy current regio
n
,
T
i
s
th
e temp
eratu
r
e,
t
is
the
time,
σ
is
the c
onduc
tivity,
ν
is the reluctivity,
J
t
,
J
e
and
J
s
are, res
p
ec
tively, the total c
u
rrent
,
eddy cu
rrent and source
current
den
sity.
Joul
e he
at loss
P
c
in th
e co
ndu
ctor
and e
ddy cu
rre
nt loss
P
t
in the en
clo
s
ure a
r
e
expre
s
sed a
s
:
2
s
c
V
1
2(
)
Pd
v
T
J
(
4
)
2
e
t
V
1
2(
)
Pd
v
T
J
(
5
)
Assu
ming th
e outer b
oun
dary of the solutio
n
regi
on is far a
w
ay from the GIB. The
boun
dary con
d
ition on
Г
1
is:
1
|
0
A
(
6
)
Bounda
ry
Г
2
is a symmet
r
i
c
al bo
und
ary of which the magneti
c
ind
u
ction i
s
0 in
y
- an
d
z
-
axis dire
ction
s
. The bo
und
ary con
d
ition
on
Г
2
is expre
s
sed a
s
:
||
0
BB
yz
AA
(
7
)
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 7, July 201
4: 5003 – 50
10
5006
4. Three-Dim
e
ntional Th
e
r
mal Model
Conve
c
tion a
nd ra
diation
are the m
o
st
infl
uential he
at transfe
r m
e
ch
ani
sm be
cau
s
e th
e
heat gen
erat
ed in GIS bus ba
r get
s dissipate
d
mainly by con
v
ection an
d radiatio
n to the
surro
undi
ngs.
The solutio
n
regio
n
and
finite element mesh of eddy-cu
rre
nt field and CFD
analysi
s
i
s
id
entical, thu
s
power lo
sse
s
can
be m
app
ed into the
r
m
a
l field by the
element
with
the
same
num
be
r. Unli
ke the t
r
adition
al FE
M in whi
c
h th
e co
nvectio
n
boun
dary
con
d
ition is n
eed
ed
and the heat
transfe
r co
e
fficient on the tank su
rfa
c
e is viewed
as co
nsta
nt, an air dom
ain
outsid
e
the G
I
S bus b
a
r
h
a
s al
so
bee
n
model
ed for
simulatin
g
th
e heat tran
sfer by
conve
c
t
i
on
and
ra
diation
to the
surrou
nding
s. T
he
natural
conve
c
tion
both
in
side a
n
d
out
side the
GIS
b
u
s
bar a
r
e
solve
d
with the
CF
D theo
ry. The
steady-s
tate
governi
ng e
q
uation
s
for
CFD an
alysi
s
a
r
e
employed a
s
follows [11-1
3
]:
Contin
uity equation:
()
0
V
(
8
)
Momentum e
quation:
x
-ax
i
s dir
e
ct
io
n:
()
(
)
p
uu
x
V
(
9
)
y
-ax
i
s dir
e
ct
io
n:
()
(
)
y
p
vv
f
y
V
(
1
0
)
z
-ax
i
s dir
e
ct
io
n:
()
(
)
p
ww
z
V
(
1
1
)
Energy eq
uat
ion:
v
()
(
)
CT
T
Q
V
(
1
2
)
Whe
r
e
ρ
,
λ
a
nd
μ
are,
re
spectively, the
den
sity, therma
l co
ndu
ctivity, and dyna
mic visco
s
ity,
V
is
gas veloc
i
ty,
u
,
v
a
nd
w
a
r
e
,
respe
c
tively, the velo
city compon
ents in
x-, y- a
nd
z-axis di
re
ction
s
,
p
is the
ga
s
pre
s
sure,
I
is the identity matrix,
C
is t
he specific heat,
Q
v
is the volumetri
c
h
eat
sou
r
c
e
,
f
y
is the gravitational acceleration in
y
-ax
i
s dir
e
ct
ion
, T
is K
e
lvin tempera
t
ure.
Prope
r bou
n
dary co
nditio
n
s are ne
ce
ssary for the
r
mal analysi
s
of GIS bus b
a
r. In th
e
external ai
r
domain, ai
r i
s
tre
a
ted a
s
ideal g
a
s.
Consta
nt temp
eratu
r
e b
oun
dary
conditio
n
is
applie
d on th
e outmost bo
unda
ry of air domain, state
d
as:
1
a
|
TT
(
1
3
)
Whe
r
e
T
a
is t
he ambie
n
t temperature.
Non
-
sli
p
bou
ndary conditi
ons a
r
e ap
pli
ed on
Г
1
,
Г
3
and
Г
4
:
0
xy
z
VV
V
(
1
4
)
There is radi
ation heat tra
n
sfer
betwee
n
the co
ndu
ct
ors
and tan
k
and bet
wee
n
the tank
and
su
rro
undi
ng ai
r. The
r
m
a
l ra
diation
h
eat tran
sfe
r
h
a
s l
a
rg
e effe
cts on t
he ove
r
all tempe
r
atu
r
e
rise of GIS b
u
s ba
r, esp
e
cially when the
tem
peratu
r
e
differen
c
e in
crea
se
s and th
e conve
c
tion
is
natural. Be
ca
use
the h
eat f
l
ow that
ca
uses
radi
ation v
a
rie
s
with the
fourth
po
wer of the a
b
solu
te
temperature,
the
the
r
mal
a
nalysi
s
con
s
i
derin
g radi
ation i
s
hi
ghly n
online
a
r. T
h
e
ra
diation
effe
cts
Evaluation Warning : The document was created with Spire.PDF for Python.
TELKOM
NIKA
ISSN:
2302-4
046
Thre
e-Dim
e
n
s
ion
a
l The
r
m
a
l Analysis of
Three
-
Pha
s
e
Enclosed GI
S Bus Bars
(Li Hon
g
tao)
5007
gene
rally app
ear in the h
e
a
t transfe
r an
alysis o
n
ly throug
h the bo
unda
ry con
d
itions. T
w
o types
of ra
diation
b
ound
ary
co
nd
itions
are u
s
e
d
in
the
mod
e
l. On
the
out
er ta
nk surfa
c
e (
Г
3
), an
op
e
n
type enclo
su
re surfa
c
e
radi
ation bou
nda
ry condition i
s
applie
d as foll
ows:
3
44
a
|(
)
T
TT
n
(
1
5
)
Whe
r
e
n
is th
e norm
a
l dire
ction of tank
surfa
c
e,
ε
is
emis
s
i
vity,
σ
is Stefan-Boltzmann con
s
ta
nt,.
Between the
outer surfa
c
e
of the condu
ctor
s and the
inner surfa
c
e of the tank (
Г
4
), a
clo
s
ed
type e
n
clo
s
u
r
e su
rface ra
diation
is con
s
id
er
ed
. Ea
c
h
r
a
d
i
atin
g
s
u
r
f
ac
e
is
ch
ar
ac
te
r
i
ze
d
with an e
m
issivity and th
e sam
e
en
cl
osu
r
e n
u
mbe
r
assig
ned t
o
it. The formulation of t
h
is
boun
dary con
d
ition is expressed a
s
[14]
;
4
44
|(
)
ij
i
j
T
FT
T
n
(
1
6
)
Whe
r
e
T
i
and
T
j
are the temperature
s
o
f
the radiatin
g two su
rface
s
,
F
ij
is the view facto
r
, wh
ich
can b
e
obtain
ed by the followin
g
equati
on:
2
cos
c
o
s
1
ij
ij
ij
i
j
i
AA
Fd
A
d
A
A
r
(
1
7
)
W
h
er
e
A
i
an
d
A
j
a
r
e
area
s of
the t
w
o
surfa
c
e
s
,
r
i
s
the
distan
ce
between
the
two
surfa
c
e
s
,
θ
i
and
θ
j
a
r
e the
polar an
gle
s
formed by the
radiat
ion lin
e
and the normal of the two surfa
c
e
s
.
Finally, adia
batic
boun
da
ry co
ndition
i
s
a
dopte
d
a
nd the
ga
s
velocity in th
e
x
-
a
xis
dire
ction is 0
on
Г
2
, stated as:
2
Γ
00
x
T
V
n
，
(
1
8
)
In orde
r to ensure
soluti
on accu
ra
cy of
the thermal model, the thermal
physi
cal
prop
ertie
s
except th
e
spe
c
ific
heat
of t
he SF
6
ga
s and air
are consi
dered
to
be
tem
peratu
r
e
depe
ndent in
the CF
D an
alysis. Th
e d
ensity vari
ati
on with the t
e
mpe
r
ature
and p
r
e
s
sure
is
evaluated by
the ideal ga
s
law.
0
0
0
pT
pT
(
1
9
)
The the
r
mal
con
d
u
c
tivity and visco
s
ity o
f
gas a
r
e n
e
a
r
ly not influ
e
n
c
ed
by g
a
s pressure.
Their vari
atio
n with tempe
r
ature is o
b
tai
ned by Suthe
r
land’
s la
w [15].
1.5
0
0
0
TS
T
TT
S
(
2
0
)
1.5
0
0
0
TS
T
TT
S
(
2
1
)
Whe
r
e
ρ
0
,
λ
0
and
μ
0
a
r
e,
re
spe
c
tively, the de
nsity, the
r
mal
co
ndu
cti
v
ity and dyna
mic visco
s
ity
of
the SF
6
ga
s and
air at
0
℃
,
S
i
s
the
Sutherl
and
tempe
r
ature,
T
0
and
p
0
are
th
e
r
e
fer
e
nc
e
temperature
and pressu
re,
resp
ectively.
Adiabatic
bou
ndary
con
d
ition is a
dopte
d
and the g
a
s
velocity in the
x
-axi
s directi
on is 0
on bou
nda
ry
Г
2
, stated as:
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ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 7, July 201
4: 5003 – 50
10
5008
2
Γ
00
x
T
V
n
，
(
2
1
)
5. Results a
nd Discu
ssi
ons
5.1. Po
w
e
r L
o
sses
The numerical s
i
mulation is
c
a
rried out with ANSYS 12.0. The power loss
es
in GIS bus
bar are
cau
s
ed by
both
current flo
w
ing
in the
co
n
d
u
c
tors
and
ed
dy cu
rrent in
duced i
n
the
tank.
Becau
s
e th
e conta
c
t re
si
stance is temp
eratu
r
e de
pe
ndent, the ed
dy current a
n
d
thermal fiel
ds
are
solved ite
r
atively. Firstl
y, the initial tempe
r
atures
are a
s
sum
ed
in the conta
c
ts an
d the oth
e
r
comp
one
nts
of GIS bus
ba
r. Then, the i
n
itial temp
e
r
a
t
ures are cont
inually
upd
a
ted until the
error
betwe
en the
cal
c
ulate
d
temperatur
e a
n
d
the initial value is le
ss than 5%. Assuming the
co
ntact
resi
stan
ce
of
each ph
ase t
o
be
20
μΩ
, t
he ed
dy current dist
ributio
n in the ta
nk
of GIS bu
s b
a
r at
rated
current
2000
A i
s
giv
en in
Fig
u
re
4. The
po
we
r losse
s
i
n
the
thre
e-p
h
a
s
e
con
d
u
c
tors
a
n
d
in the conta
c
t
s
of the GIS bus ba
r ar
e 34
2.95 W an
d 5
1
.31 W, re
sp
ectively.
Figure 4. Eddy Curr
ent Di
stribution o
n
the Tank Su
rfa
c
e
5.2. Tempera
t
ure Di
stribu
tion
The pressu
re
of SF
6
gas is 0.35MPa.
The cal
c
ul
ate
d
power lo
sses are used
as he
at
sou
r
ce in
the
CF
D a
nalysi
s
. Steady-sta
te co
njugate
heat tra
n
sfe
r
analy
s
is i
scondu
c
ted
at t
h
e
ambient te
m
peratu
r
e
25
Ԩ
. The
temp
eratu
r
e
distri
bution
of
GI
S bus ba
r
u
nder the
cu
rrent of
2000 A is shown in Fig
u
re 5. The
maximum te
mperature lo
cate
s at the conta
c
ts an
d the
con
d
u
c
tors o
f
phase A a
nd C have
nearly ide
n
tical tempe
r
at
ure di
strib
u
tions. The
co
ntact
temperature
of pha
se B i
s
87.2
Ԩ
, a
nd t
hat of ph
ase
A and
C i
s
9
1
.7
Ԩ
. Thi
s
is attributed t
o
the
symmetri
c
sp
atial locatio
n
s
of pha
se A
and C,
a
nd t
he flow
cha
r
a
c
teri
stics of h
eated SF
6
ga
s,
whi
c
h m
o
ves upwards
un
der th
e effe
ct of buoya
n
cy
and
brin
gs h
e
at to the
up
per
part
s
of
GIS
bus
bar. T
he
conve
c
tive he
at tran
sfer
co
efficient
on th
e tank
su
rface is
cal
c
ulate
d
with
Ne
wto
n
’s
law of co
oling
.
The distrib
u
tion is given i
n
Figure 6. The
x
- a
nd
y
-
d
ir
e
c
tion
s
ar
e
s
h
ow
n
in
F
i
gu
r
e
3. The heat transfe
r co
efficient is proved
to be vari
able at different locatio
n
s on t
he tank surfa
c
e.
The maximu
m value is 4.5W/(m
2
K) at
the position
of
y
=
0
. L
a
r
ge d
i
s
c
r
e
pa
nc
y e
x
is
ts
b
e
twee
n
the maximum
value and th
e minimum o
ne.
Figure 5. Te
mperature
Di
stri
butio
n of the GIS Bus Bar
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TELKOM
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ISSN:
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046
Thre
e-Dim
e
n
s
ion
a
l The
r
m
a
l Analysis of
Three
-
Pha
s
e
Enclosed GI
S Bus Bars
(Li Hon
g
tao)
5009
Figure 6. Hea
t
Transfe
r Co
efficient Di
stri
bution on the
Outer Ta
nk S
u
rface
5.3. Labora
t
or
y
Tests
In order to
check th
e
accuracy
of th
e
p
r
op
osed
methodol
ogy, labo
rato
ry t
e
sts a
r
e
con
d
u
c
ted o
n
a 126
kV GIS
bus
ba
r p
r
ot
otype, whi
c
h i
s
sho
w
n in
Fi
gure
7. The
tempe
r
atures
are
measured wi
th
Pt100
tem
peratu
r
e se
n
s
ors, whic
h are
in
stalle
d on
the
tan
k
surfa
c
e, on
t
h
e
conta
c
t of
ea
ch
pha
se, a
n
d
on th
e mid
d
le of th
e
co
ndu
ctors. Th
e ambi
ent te
mperature
is
also
measured
wi
th a
sen
s
o
r
installe
d 2
meters a
w
ay
from th
e G
I
S bus ba
r.
Con
s
id
erin
g
the
environ
menta
l
factor, N
2
gas
with the pressu
re of
0.4MPa is sub
s
tituted for SF6 ga
s. The
c
o
nd
uc
to
rs
ar
e
co
n
n
e
c
ted in
s
e
r
i
e
s
and
fe
d
w
i
th
a
c
u
rr
en
t s
o
urce
. Be
fo
r
e
th
e e
x
p
e
r
imen
t, th
e
conta
c
t resi
st
ance of ea
ch
pha
se i
s
me
a
s
ured. Th
e co
ntact resi
stan
ce of p
h
a
s
e A
,
phase B, an
d
pha
se
C a
r
e,
re
spe
c
tively, 42.6
μΩ
, 43.
8
μΩ
, and
44.
2
μΩ
. Co
mpa
r
ison
between
the tested
a
n
d
cal
c
ulate
d
te
mperature
ri
ses
at differen
t
load
cu
rrent
s i
s
give
n in
Table
3. Th
e
mea
s
u
r
eme
n
t
points
are sh
own i
n
Fig
u
re 1. It is fou
nded th
at
the
conta
c
t tem
peratu
r
e
ri
se
s a
r
e hi
ghe
r
than
those of oth
e
r co
mpo
nen
ts in GIS bus bar,
an
d the tempe
r
atu
r
e differe
nce
becom
es m
o
re
obviou
s
as th
e cu
rre
nt increases. Th
e calcul
ated
tem
peratu
r
e
rise
s are in goo
d
agre
e
ment
with
the tested results.
Figure 7. Experime
n
tal Set-up of the 12
6kV Th
ree
-
ph
ase GIS Bus
Bar
Table 3. Co
m
pari
s
on of the
Simulat
ed an
d Teste
d
Te
mperature
Ri
se
s (K)
Meas
ur
eme
n
t poi
nts
C
u
rre
nt
I
=1
00
0 A
C
u
rre
nt
I
=1
98
0 A
Si
mu
l
a
te
d Te
s
t
ed Si
mu
l
a
te
d Te
s
t
ed
1
17.
7
15.
9
54.
1
46.
6
2
16.
4
15.
2
49.
4
43.
7
3
18.
1
18.
2
54.
6
51.
8
4
16.
9
17.
2
50.
0
49.
3
5
18.
0
17.
8
54.
7
52.
5
6
16.
7
17.
0
50.
0
48.
9
7 5.9
5.3
17.
1
16.
0
4. Conclusio
n
Conta
c
t resi
stan
ce h
a
s
to be
con
s
i
dere
d
in th
e
thermal
an
alysis
of three-p
h
a
s
e
encl
o
sed
GIS bus ba
rs.
In this
pape
r, the conta
c
t re
sista
n
ce i
s
simplified
to be
a
re
sistor
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 7, July 201
4: 5003 – 50
10
5010
betwe
en the
con
d
u
c
tor
a
nd the
conta
c
t finge
r in t
he solid m
o
del. The
am
bient air is
also
introdu
ce
d in
to the soluti
on re
gion to
avoid
the convective bo
unda
ry
co
ndi
tion on the tank
s
u
r
f
ac
e
.
T
h
e
3
-
D F
E
M is us
e
d
to
s
o
lve th
e
c
o
up
led
e
ddy current, fl
uid a
n
d
therm
a
l p
r
obl
em. T
he
model p
r
op
osed is valid
ate
d
with the te
st resu
lt
s on a
126kV
GIS bus ba
r p
r
otot
ype. The mo
del
is helpful in d
e
termini
ng th
e conta
c
t tem
peratu
r
e in GI
S bus ba
r.
Referen
ces
[1]
Run
de M, Li
lle
vik O, Larsen
V. Cond
ition
a
ssessm
ent of
contacts in
ga
s-insul
a
ted s
u
b
s
tations.
IEEE
Tra
n
s
a
c
ti
on
s on
Po
we
r D
e
l
i
v
ery
. 2004; 19(
2): 609-6
17.
[2]
Mukai
y
am
a Y,
T
a
kagi I, Izumi K. Investi
gati
on o
n
ab
normal
phe
no
mena of cont
acts usi
n
g
disco
nnecti
ng
s
w
itc
h
a
n
d
det
acha
ble
b
u
s i
n
300
kV GIS.
IEEE Transactions on Power
Delivery
. 19
90;
5(1): 189-
19
5.
[3]
Mukai
y
am
a Y, T
a
kagi I,
Izumi K. Contact-fail
ur
e ph
en
omen
a and the
i
r de
velo
pment in g
a
s-ins
u
late
d
sw
i
t
ch
ge
a
r
.
Ele
c
trical Eng
i
ne
e
r
ing i
n
Japa
n
. 199
3; 113(
2): 733-7
40.
[4]
H
w
an
g C
C
, Ch
ang
JJ, Jia
ng
YH. Ana
l
ysis
of electrom
ag
net
ic an
d th
ermal
fields f
o
r a
bus
duct s
y
stem.
Electric Power System
s Res
e
arch
. 199
8; 45(
1): 39-45.
[5]
Hedi
a H, He
nr
otte F
,
Me
y
s
B
,
et al. Arrang
em
ent of p
has
e an
d he
at co
nstraints i
n
a
bus b
a
r.
IEEE
T
r
ansactio
n
s o
n
Magn
etics
. 1999; 35(
3):n1
2
74-1
277
．
[6]
Kim JK, Hahn SC, Park KY.
T
e
mperature rise pre
d
i
c
tion of EHV GIS bus bar b
y
cou
p
le
d
magn
etotherm
a
l finite e
l
eme
n
t
method.
IEEE Transactions
on Magnetics
. 200
5; 41(5): 1
636-
163
9.
[7]
Kim SW, Kim
HH, Hahn SC. Coup
led fi
nite
-eleme
nt-an
a
l
y
tic techniq
ue f
o
r pred
iction
o
f
temperatur
e
rise in p
o
w
e
r a
ppar
atus.
IEEE Transactions
on Magnetics
. 200
2; 38(2): 92
1-92
4.
[8]
Ho SL, Li Y, Li
n X. Ca
lcul
atio
ns of edd
y cur
r
ent,
fluid, an
d
thermal fiel
ds in an a
i
r insu
la
ted bus d
u
ct
sy
s
t
e
m
.
IEEE Transactions on Magnetics
. 2007; 43(
4): 143
3-14
36.
[9]
Ho S
L
, L
i
Y,
L
i
n
X. A
3-
D st
ud
y
of e
d
d
y
c
u
rr
ent fi
eld
a
n
d
temp
eratur
e
rises i
n
a c
o
m
pact b
u
s
duct
sy
s
t
e
m
.
IEEE Transactions on Magnetics
. 2006; 42(
4): 98
7-99
0.
[10]
Paulk
e
J, W
e
ichert H, Stein
hae
user
P. T
h
ermal simu
lati
on of s
w
itchg
ear.
IEEE Transactions on
Co
mp
one
nts a
nd Packa
gi
ng
T
e
chno
log
i
es
.
200
2; 25(3): 43
4-43
9.
[11]
Raja
go
pal
a K,
Pand
ura
nga
V,
Lun
avath
H.
Comp
utation
o
f
electric
fi
eld
and t
herma
l pr
operti
es of
3-
phas
e cab
l
e.
T
E
LKOMNIKA Indo
nesi
an Jo
u
r
nal of Electric
al Eng
i
ne
eri
n
g
.
2012; 1
0
(2): 2
65-2
74.
[12]
W
u
XW
, Sh
u N
Q, Li HT
.
T
hermal a
n
a
l
ysis i
n
gas
ins
u
late
d t
r
ansmissi
on
li
n
e
s usi
n
g
an
im
prove
d
fin
i
te-
elem
ent mode
l
.
T
E
LKOMNIKA Indones
ia
n Journ
a
l of Electr
ical En
gin
eeri
n
g
. 2013; 1
1
(1): 458-
467.
[13]
Lee
SH, L
ee B
Y
, Kim HK. L
o
c
al h
eat s
ourc
e
ap
pr
o
x
imatio
n tech
niq
ue f
o
r pred
ictin
g
tem
peratur
e ris
e
in po
w
e
r capac
i
tors.
IEEE Tra
n
sactions on M
agnetics
. 200
9; 45(3): 125
0-1
253.
[14]
Eteiba
MB, Az
iz AMM, Shaz
l
y
JH. H
eat c
ond
uctio
n
pr
o
b
lems
in
SF
6
gas c
ool
ed-i
n
s
u
late
d p
o
w
e
r
transformers s
o
lve
d
b
y
the fi
nite el
eme
n
t method.
IEEE Transactions on
Power Deliv
ery
.
2008; 2
3
(3):
145
7-14
63.
[15] Anders
on
JD.
Co
mp
utation
a
l F
l
uid
Dy
na
mic
s
. Ne
w
Y
o
rk: McGra
w
-
Hil
l. 19
95.
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