De s cript ion
Title of Invention:
VACUUM INSULAT]ON SWITCHGEAR AND METHOD FOR REPLACING MOLD
SWITCH
Technical Fietd
t00011
The present invention relates to a vacuum insuration
switchgear and a method for repracing a mord switch and in
particular to a vacuum insul-ation switchgear equipped with a
mord swi-tch formed by integrating a vacuum break switch portion
and a disconnector with an earthing function by epoxy casting
and suitabl-e for use in erectric power receiving/transformj-ng
facirities and a method for replacing the mol_d switch.
Background Art
[0002]
Erectric power receiving/transforming
faciriti_es are
usuarry equipped with an encrosed switchboard (hereafter,
referred to as switchgear) housing: a vacuum circuit breaker
for interrupting load current or faul-t current; a disconnector
and an earthing switch for ensuring an operator, s safety when
he/she maintains and inspects a r-oad; detectors for system
voltage and system current; a protection relay; and the Ilke.
t00031
The insulation method for the switchgear is of great
variety. rn addition to conventional aerial insuration and
15
20
atr
LO
3
gas insuration using SE6 gas, solid insuration, compressed air
insuration, and furr vacuum insulation have recentry come arong
from the viewpoint of environmental- protection. The adoption
of these types of insuration methods has accererated the
downs izinq of each component of circuit breaker, disconnector,
and earthing switch.
[0004]
under these circumstances, a vacuum insuration swit,chgear
housing a device formed by integrating the forrowing by epoxy
casting in a cabinet has been recently proposed: a vacuum break
switch portion having an interrupting function and a simirarly
aerially insul-ated disconnector with an earthing function (EDS) .
(Refer
to Patent Literature 1. )
[000s]
The above-mentioned vacuum insulation switchgear is
obtained by integrating a vacuum vesser housing a vacuum break
switch portion having an interrupting function and a
disconnector with an earthing function (EDS) by epoxy casting
and pracing the integrated device in a cabinet. Because of
its smarr size, right weight, and high reriabiJ-ity, the vacuum
insulation switchgear canmeet the requirement of size andweight
reduction for criticar facilities, such as power distribution
facilities, in urban areas.
t00061
15
20
25 With respect to electric power receiving/transforming
4
facilities/ users, demands have been diversified An example
10
wirr be taken. The type of a road and operating conditions
therefor vary depending on its intended
use; therefore, the
reguired l-evers of safety, reliabirity,
operation and
maintenance, and future increase in load are taken into account
to plan an el-ectric distribution system. rn pranning an
electric distrlbution system, consideration must also be given
to the contro.l- of a circuit breaker, a disconnector, an earthing
switchr d,.d the rike comprising erectric power
receiving/transforming
facilities
and the monitoring and
measuring of the vortage, current, erectric power, and the rike
of the erectric power receiving/transforming
facirities.
[0007]
fn this case, it is important
to reduce the space of
instarration
of the equipment, such as the circuit breaker,
disconnector, earthing switch, and the r-ike, control equipment
therefor, andmonitoringandmeasuringequipmenttherefor.
The
investment in the instarration
of these pieces of equipment
is thereby reduced.
[0008]
To meet these demands, especiarry, to reduce the overarr
size of a switchgear, it is very important
to reduce the size
of the rel-evant switching device unit portion as principal
equipment. rt is desired to instalr the switching device unit
in a minimum necessary installation space.
15
20
25
10
[000e]
Meanwhile, customers demand to shorten the duration of
service interruption as much as pos sible even if a troubre occurs
in a mord switch housed in the switching device switch portion
during on-site operation. This i-s done by replacing the mord
switch involvinq the tror.rbre with a new morded coir in as short
a time as possible.
[0010]
In ordinary cases, the replacement of the entire
switchgear is the restoration work that can be conducted in
the shortest time. rn this case, the cost burden of the
switchgear for replacement is increased,. therefore, customers
desire to replace only a criticar part invor-ving a troubl-e to
reduce the cost burden as much as possible.
[0011]
Because of this, it is important to take the forlowing
measures: the vorume of the mord switch housing portion of the
switching device unit portion is reduced as much as possible
for the reduction of the size of the switchgear; and should
15
20 a trouble occur
swiftly removed
with a new mold
[0012]
A description
a mold switch with
in a mold switch portion, the mo1d switch is
from the switchgear so that it can be replaced
switch.
will be given to this method for replacing
reterence to EIG. 6.
ZJ
10
t00131
As shown in EIG. 6, during operation (EIG.
6 (a)
) ,
a mold
switch 20 obtained by integrarly molding the for]owing members
by epoxy resin is secured in a cabinet 1 by a mord switch securing
member 2l: a vacuum break switch 8 having an interrupting
function instal-l-ed in a switching device section 1b; and a
three-position disconnecting switch having
disconnection/earthing functj-on. This mold switch securing
member 2l is secured on a switching device support member.
[0014]
rf a troubl-e occurs in a mord switch 20 and an attempt
is made to reprace it with a new mord switch in this state,
a probrem wirr arise. A bus-side bushing 25 of the mol_d switch
20 is projected from the mold switch 20 in the height direction
of the bus-side bushrng 25 (dimensj-on
L in the drawing) . In
this state, therefore, the bus-side bushing 25 interferes and
it is difficutt to take the mord switch 2o out of the switchgear.
[001s]
To cope with this, usuarry, a space with the same dimension
L as the dimension L in the height direction by which the bus-side
bushing 25 of the mord switch 2o is projected upward is ensured
at the lower part of the mord switch 20. To reprace a mord
switch invorving a troubre, as shown in FrG. 6 (b)
, the mord
switch 20 invorving the trouble, removed from the mol_d switch
securing member 21, is moved down to the space with dimension
15
20
atr
LJ
10
L ensured at the rower part of the mord switch 20. As shown
ErG. 6(c), thereafter, the mord switch 20 is purred out of the
area embracj-ng the space ensured at the rower part thereof in
the horizontal direction by a rifter or the rike and taken out
of the switchgear. After the mold switch 20 involving the
trouble is taken out of the switchgear, a new mor-d switch for
replacement is installed in the switching device section 1b
by procedures reversing the above. The mord switch securing
member 21 is secured on the switching device support member
and the mord switch securing member 2! ts secured in the cabinet
1.
Citation List
Patent Literature
[0016]
Patent Literature Japanese Unexamined Patent
2010-44928 Application Publication No
Summary of Invention
Technical Problem
[0017]
The above-mentioned method for replacing a mold switch
poses a problem. rt is necessary to ensure beforehand a space
with the same dimension L as the dimension L of the bus-side
bushing of the mord switch in the height direction at the rower
part of the mold switch. As shown in FIG. 6, the length in
the height direction of the mord switch with this space taken
1 15
ZU
25
10
B
into account is 2L+La. (La
is the dimensi_on of the mord switch
in the height direction except the dimension L of the bus-side
bushing in the height direction. ) This used to interfere with
the reduction of the overall- size of switchgear.
[0018]
The invention has been made in consideration of the
foregoing. An object of the invention is to provide a vacuum
insuration switchgear in which a mold switch can be replaced
without increasing the overarr size of the switchgear and a
method for replacing the mol-d switch.
Solution to Problem
[0019]
To achieve the above object, vacuum insul-ation
switchgear is characterized in that it incl-udes: a cabinet
incruding a switching device sectionwith an operatj_on mechanism
portionplacedthereunder, a bus section inwhich abus is praced,
a cabre section in which a cable is placed, and a contror section,
each of these sections being partitioned by a grounded metar
plate; a mord switch install-ed in the switching device section
and obtained by integrally molding a vacuum break switch having
an interrupting function and a three-position disconnecting
switch having a dlsconnection/earthing function, these
switches being operated by the operation mechanism portion;
a mord switch securing member securing the mold switch in the
cabinet; and a switching device support member supporting and
15
20
25
10
9
securing the mord switch securing member. The bus section is
formed above the central part of the cabinet; the switching
device section is formed at the lower part of the bus section;
the cabre section is formed on the rear face side of the cabinet;
and the contro] section is formed on the front face side of
the cabinet. A bus-side bushing projected in the height
direction of the mold switch and the bus are connected with
each other; and a cable-side bushing proj ected in the horizontaf
direction of the morded coir and the cabre are connected wlth
each other. fn this vacuum insulation switchgear, the spacing
between the morded coir and the operation mechanism portion
placed thereunder is shorter than the length of the bus-side
bushing projected in the height direction of the morded coil.
[0020]
To achieve the above object, the method for replacing
a mord switch of the invention is for repracing a moJ_d switch
formed by integrarry molding a vacuum break switch having an
interrupting function and a three-position disconnecting
switch havi-ng a disconnection/earthing function, placed in a
switching device section partitioned by a grounded metar plate
and operated by an operation mechanism portion pJ_aced thereunder,
in which mol-d switch a bus-side bushing projected in the height
direction and a bus are connected with each other and a cable-side
bushing pro;ected in the horizontar direction and a cabl_e are
connected with each other. The method for repracing a mord
15
20
25
10
10
switch is characterized in that the folrowi_ng procedure is taken
to reprace the mold switch: the connection between the bus-side
bushing and the bus and the connection between the cabl_e-side
bushing and the cabre are removed; the fastening of a mold switch
securing member securing the mord switch in the cabinet and
the fasteni-ng of a switching device support member supporting
and securing the mold switch securing member are removed;
thereafter,
the mold switch securing member is pul1ed upward
by equar to or more than the projecting size of the bus-side
bushing in the height direction; subsequently, the mold switch
is pulred out in the horizontal direction and taken out of the
switchgear; and then a mold switch for repracement
is insta]red
in the switching device section by procedures reversing the
above.
Advantageous Effects of fnvention
[0021]
The invention
the overall si ze of
mold switch portion
replaced.
brings about both the following effects:
a switchgear can be reduced; and when a
breaks down, only that mold switch can be
Brief Description of Drawings
10022)
IFrG. 1] ErG. 1 is a side view of an embodiment in which
vacuum insulation switchgear of the invention is applied as
feeder paner, illustrating it in operation in the form of
1tr
fJ
20
25
10
11-IocaI sectional view.
IErG. 21 FrG. 2 is a perspective view of an embodiment
in which the vacuum insul-ation switchgear of the invention shown
in FrG. 1 is appried as a feeder pane1, ilrustrating it during
repracement
of a mold switch in the form of l_ocar sectional
.-..i
^. -[EIG.
3] FIG. 3 is a perspective view illustrating
a
ion switchgear
switching device comprising the vacuum insulat
of the invention shown 1n FIG. 1.
IFrG. 4] FrG. 4 is a pran view irrustrating a switching
device comprising an embodiment of a vacuum insulation
switchgear of the invent
j_on.
IE]G. 5l FrG. 5 is a drawing for expraining a method for
repracing a mord switch in an embodiment of a vacuum insuration
15 switchgear of the invention
IEIG. 6] FIG. 6 is a
for replacing a mold switch in
switchgear.
Description of Embodiments
t00231
drawing for explaining a method
a conventional vacuum insul-ation
20
Hereafter, a descri-ption wifl be given to an embodiment
of a vacuum insul-ation switchgear of the invention with reference
to the drawings.
1002 4
)
Z' FrG. 1 ill-ustrates an embodiment in which a vacuum
10
12
insulation switchgear of the invention is applied as a feeder
paner. rn the drawing, the cabinet 1 of the vacuum insuration
switchgear incrudes a bus section 1a, a switching device section
1b incruding an operation mechanism portion, a cabre section
7c, and a contror section 1d each of which is partitioned by
a grounded metal pJ_ate.
to02sl
The bus section 1a is formed above the central part of
the cabinet 1; the switching device section 1b is formed at
the Iower part of the bus section l_a; the cable section 1c is
formed on the rear face side (l-eft
side of FIG. 1) of the cabinet
1; and the control section 1d is formed on the front face side
(right
side of FIG. 1) of the cabinet 1.
loo26)
rn the bus section 1a, sorid insul-ated three-phase buses
5 are placed in pararrer to the front face of the cabinet 1.
The buses 5 are rendered gasress by sorid insuration to ensure
ease of handring and safety. rn the switching device section
1b, a vacuum break switch 8 having an interrupting function,
a three-position disconnecting switch 9 having a
disconnection,/earthing function, and an operation mechanism
portion 10 are placed.
10021 )
The cabre section l-c is provided with: a terminar 2a for
cabre connection connected to a fixed erectrode of the vacuum
l5
20
?10
13
break switch B and led into the cabl-e section 1c; a T-shaped
cabre head 2 rotatabry provided at the terminar 2a; a cabre
3 connected to the terminar 2a by the T-shaped cable head 2;
and a current transformer (cr)
4 provided at the cabl_e 3. fn
this exampre, the cable 3 is led from the rower part of the
cabi-net l- into the cabre section l-c. rn the cabre section 1c,
the terminal 2a for cabre connection is provided on the periphery
thereof with a current transformer (cr) 6 for systemprotection.
t002Bl
The control- section 1d is praced above the operation
mechanismportion 10 on the front face side (right
side of ErG.
1) of the cabinet 1. Thus consideration is given to the
prevention of increase in the size of the cabinet 1 in the height
di-rection in the place of installation.
t002el
rn the thus configured vacuum insuration switchgear in
this embodiment, the forrowing measure is taken: the
above-mentioned vacuum break switch B and three-position
disconnecting switch 9 are integralry morded by epoxy resin
and instarred in the switching device section 1b as are supported
by the switching device support member 24. with respect to
the mord switches 20 instarred in the switching device section
1b, the forrowing measure is taken so that they can be easiry
replaced: each mord switch is removabJ-y secured by a fastening
means 22 such as a bolt on the mord switch securing member 21
15
20
25
10
14
removabry
connected to the switching device support member 24
by a fastening means such as a bort. An opening (not
shown)
that arrows a mold switch 20 to be taken out is formed on the
switchgear rear face side of a portion of the switching device
support member 24 comprising the cabinet 1 where a mord switch
20 is praced. The opening is so configured that the forrowing
is impremented:
during operation, the opening is cJ_osed by a
rid (not
shown) fastened by a bort; and when a mord switch 2o
is replaced, the bott is unfastened and the rid is removed so
that the mord switch 20 can be pulred out of the opening.
[0030]
As described above, each mold switch 2o is unitized for
size and weight reduction and this faciritates
repraci_ng work.
rn addition, the three unitized mold switches 20 are of phase
separation structure as irrustrated
in FrG. 3 and FrG. 4. They
are arranged in three rows orthogonarly to the front face of
the cabinet 1 and an interphase grounded metal prate 23 is praced
between phases to suppress the occurrence of a short circuit
accident between phases. The interphase grounded metar prates
23 are fastened to the mo.r-d switch securing member 2L by a
removabre fastening member such as a bort. rn addition, the
outer surface of each mold switch 2o is painted with conductive
paint and grounded to ensure safety against contact and the
li,ke.
t00311
15
20
25
10
15
with respect to the spacing between the mord switches
20 and the operation mechanism porti-on 1o praced thereunder,
the forlowing measure is conventionalry taken: a space with
the same dimension L as the dimension L by which the bus-side
bushing 25 of the mol-d switches 20 is projected upward
j-n
the
height direction is ensured. rn this embodiment, the necessity
for this measure is obviated and the spacing beLween each mold
switch 20 and the operation mechanism portion 1o is shorter
than the dj-mension Lbywhich the bus-side bush ing 25 is pro; ected
upward in the height direct
j-on.
[0032 ]
15
This makes it possible
mold switch 20 in the height
size of the switchgear.
[ 0033 ]
to take L+La as the length of each
direction and reduce the overall
20
A description wilr be given to a method for replacing
a mord switch 20 with the configuratlon in this embodiment with
reference to EIG. 5.
t00341
FIG. 5 (a) iIl_ustrates the configuration of this
embodiment in the operating state. The difference between this
configuration and that in FIG. 6 (a)
illustrating the
conventional- configuration in the operating state is as forl_ows.
rn the configuration in FrG. 6 (a)
, a spacewith the same dimension
L as the dimension L by which the bus-side bushing 25 of a mord
,q
10
l6
switch 20 is pro; ected upward in the height direction is ensured.
rn this embodiment, meanwhire, it is unnecessary to ensure a
space with dimension L and the spacing between each mord switch
20 and the operation mechanism portion 10 is shorter than the
dimension r by which the bus-side bush rng 25 is pro; ected upward
in the height direction.
[003s]
when a trouble occurs in a mord switch 20 in this stal-e
and itmust be replaced, the fol-rowing procedure is taken: first,
the connection between the bus-side bushi ng 25 of the mord switch
20 and the bus 5 and the connection between the cable-side bushing
26 and the cabre 3 are removed; further,
the bort fastening
of the switching device support member 24 and mofd switch
securing member 2t securing the mord switch 20 is removed;
thereafter, the mold switch securing member 21 is purled upward
by an amount equal to or rarger than the dimension L by which
the bus-side bushing 25 of the mold switch 2o is projected upward
in the height direction. FrG. 5(b) irlustrates this state.
(FIG.
2 al-so ilfustrates
the same state.)
[0036]
As shown in FrG. 5 (b)
, the mord switch securing member
2L ts purred up by an amount equar to or rarger than the dimension
L by which the bus-side bushing 25 of a mol-d switch 20 is pro; ected
upward in the height direction. As a result, a space exists
above the mord switch 20 where the bus-side bushing 25 i-s
15
20
25
7'7
10
positioned.
[0037]
The presence of this space brings the forrowing advantage :
even though the bus-side bushing 25 of a mol_d switch 20 is
projected upward by dimension L, there is no obstacre. As shown
in FrG. 5 (c),
a mord switch 2o invor-ving a troubr-e can be purred
in the horizontar direction out of the opening (not
shown) formed
in the switching device support member 24 and can be smoothry
taken out of the switchgear.
[0038 ]
After the mor-d switch 2o invorving
the troubre is taken
out of the switchgear, a new mord switch for replacement is
instarred
in the switching device section 1b by procedures
reversing the above. The mord switch 20 is secured on the
switching device support member 24 by the mold switch securing
member 21. The bus-side bushLnq 25 of the mor_d switch 20 and
the bus 5 are connected with each other and the cabre-side bushing
2 6 and the cabre 3 are connected with each other . This completes
the replacing work.
t003el
The adoption of the above-mentioned method for repJ_acing
a mold switch in this embodiment brings the following
advantage:
unlike conventional cases, it is unnecessary to ensure berow
the mord switches 20 a space with the same dimension L as the
dimension L by which the bus*side bush rnq 25 is projected upward
15
20
25
10
in the height direction. As shown in ErG. 5, the rength of
each mord switch in the height direction is L+La and the overarl_
size of the switchgear can be accordingly reduced.
[0040]
As a result, it is possibre to meet both of customers,
demands: the reduction in the overarl- size of a switchgear;
and the capabirity to reprace onry the rerevant mold switch
if any trouble occurs in the mold switch portion.
[0041]
fn addition to the above-mentioned effect, this
emlcodiment brings about the effect described berow. The mold
switch securing member 2t for securing mord switches 20 can
be separated from the switching device switch support member
2'7 and the interphase metal plates 23. Therefore, when these
members are removed, the mord switch securing member 27 is
reduced in weight and can be easily pulled upward.
Reference Sings List
l0o 42)
1 --- Cabinet,
l-a
--- Bus section,
1b Switching device section,
1c --- Cable section,
1d --- Control section,
2 --- T-shaped cable head,
2a --- TerminaI,
15
20
25
10
19
?
---
r--I^1^
J VqUTE,
4 --- Current transformer,
5 --- Bus,
6 --- Current transformer for system protection
I
--- Vacuum break switch,
9 --- Three-position disconnecting switch,
10 Operation mechanism portion,
20 --- MoId switch,
2l --- MoId switch securing member,
22 Eastening means,
23 Interphase grounded metal plate,
MoId swi-tch 24 Switching device support member,
25 Bus-side bushi_ng,
26 Cable-side bushing
15
10
20
Claims
IClaim 1]
A vacuum insulation
switchgear comprising:
a cabinet incl-uding a switching device section with an
operation mechanism portion praced thereunder,
a bus section
in which a bus is praced, a cable section in which a cabre is
placed, and a contror section, each of the sections being
partitioned by a grounded metal plate;
a mord switch installed in the switching device section
and obtained by integrally molding a vacuum break switch having
an interrupting
function and a three-position disconnecting
switch having a disconnection/earthing function, the switches
being operated by the operatj_on mechanism portion;
a mord switch securing member securing the mold switch
in the cabinet; and
a switching devi-ce support member supporting and securing
the mold switch securing member,
in which vacuum insuration
switchgear, the bus section
i-s formed above the centrar part of the cabinet, the switching
device section is formed at the rower part of the bus section,
the cabre section is formed on the rear face side of the cabinet,
and the control section is formed on the front face side of
the cabinet and a bus-side bushing projected in the height
direction of the mord switch and the bus are connected with
each other and a cabre-side bushing projected in the horizontar
15
20
25
2t
direction of the molded coil and the cable are connected with
each other, the vacuum insulation switchgear being
characterized in that:
the spacing between the molded coil and the operation
5 mechanism portion placed thereunder is shorter than the length
of the bus-side bushing projected in the height direction of
the molded coiI.
IClaim 2
]
The vacuum insulation switchgear according to claim 1,
L0 characterized in that:
the mold switch securing member is connected with the
switching device support member by a connectabre/removable
fastening member.
ICIaim 3
]
The vacuum insuration switchgear according to craim 2,
characterized in that:
the three mold switches are arranged in three rows with
an interphase metal plate placed in-between and the mold switch
securing member is connected with the interphase metar plate
20 by a removabl_e f astening member.
IClaim 4]
The vacuum insuration switchgear according to craim 2
or 3, characterized in that:
the fastening member is a bolt.
2s [Claim 5]
l-5
LO
22
Amethod for repracing a mord switch obtained by integralty
molding a vacuum break switch having an interrupting function
and a three-position
disconnecting switch having a
disconnection/earthing function, the switches being instal_l_ed
in a switching device section partitioned by a grounded metal
plate and operated by an operation mechanism portion placed
thereunder, in which mold switch, a bus-side bushing projected
in the height direction and a bus are connected with each other
and a cabre-side bushing projected in the horizontar direction
and a cabre are connected with each other, the method being
characteri-zed in that:
when the mord switch is repraced,
the connection between
the bus-side bushing and the bus and the connection between
the cabre-side bushing and the cable are removed, the fastening
of a mord switch securing member securing the mord switch in
a cabinet and the fastening of a switching device support member
supporting and securing the mold switch securing member are
removed, thereafter, the mold switch securing member 1s puJ_1ed
upward by equar to or more than the projecting size of the
bus-side bushing in the height direction, subsequently, the
mol-d switch 1s purred out in the horizontar direction and taken
out of switchgear, and then a mord switch for repracement is
instarred in the switching device section by procedures
reversing the above.
ICIaim 6]
15
20
25
The method for repracing a mold switch according to craim
5, characterized in that:
the fastening between the mold switch and the mold switch
securing member and the fastening between the mol_d switch
5 securing member and the switching device support member are
implemented
by a connectable/removable bolt.
Dated this 12th day of JuIy 2OL3
Of Anand and Anand Advocates
Agent for the Applicant
10
24
10
AEISTRAC