JP2972276B2 - switchboard - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a switchboard with an improved arrangement of main circuit conductors such as a power supply side conductor and a load side conductor.

[Conventional technology]

Generally, a power receiving facility has a plurality of switchboards connected in parallel to a power supply bus. Each switchboard is connected to a load via a load cable. The switchboard is provided via a partition provided inside the box.
An electric unit (chamber) and a conductive unit are formed.
A power supply side disconnecting portion and a load side disconnecting portion are provided on the partition plate.
The power supply side disconnecting part and the power supply bus are connected to the conductive unit side, and the load cable is connected to the load side disconnecting part. When the circuit breaker enters and exits the electrical room, the circuit breaker and the two disconnecting portions are electrically connected and separated. There is a drawback that the demand for load supply power increases and the number of switchboards increases as the number of switchboards increases, and a plurality of switchboards are arranged in a row board, so that there is a disadvantage that the equipment area increases.

Therefore, as a measure to reduce the number of trains, for example,
As described in Japanese Patent Publication No. 5 (1993), there has been proposed a stacked switchboard in which a housing is partitioned into three or four stages in the upper and lower stages, and an electric unit is stacked for each partitioning stage.

In the conductive unit of the stacked switchboard, the load cables of each stage are arranged so as not to wrap each other, thereby facilitating the wiring work.

[Problems to be solved by the invention]

However, the depth of the box increased, and it was difficult to reduce the installation area in spite of the reduction in the number of rows. To solve this problem, a multi-stage switchboard in which electric units are stacked in multiple stages is conceivable. However, the height is increased and the earthquake resistance is deteriorated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a switchboard having a reduced height, a lower center of gravity, and improved earthquake resistance.

Another object of the present invention is to provide a switchboard that can be safely maintained and inspected.

[Means for solving the problem]

In order to achieve this object, the switchboard of the present invention is provided with an electric unit stacked at least two steps in a box, a cable unit formed on at least one side of the electric unit, and sequentially arranged along a depth direction of the electric unit. A three-phase power source-side bus, and a three-phase load-side conductor having an insulating layer that is sequentially arranged along the depth direction on the electric unit and the cable unit and has an insulating coating. It has a coated conductive layer on the upper side that is connected to ground.

[Action]

As a result, the charging current in the insulating layer flows from the conductive layer to the ground, and no charging voltage is applied to the surface of the insulating layer. Therefore, an insulating gap is required between the upper surface of the insulating layer and the ceiling surface of the electric unit corresponding to the upper surface. As a result, the height of the box can be reduced.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 9 show a multi-stage switchboard according to the present invention, which is configured as follows.

A box 1 formed by bending a steel plate has an insertion port on the front side, and a door 2 that can be opened and closed is attached to the left and right side surfaces 1A of the insertion port of the box 1. Two partitions 3A, 3 in the box with the door 2 opened
B is installed.

An electric unit 4 is formed between the partition plate 3A and the partition plate 3B. A cable unit 5 is formed between each of the partition plates 3A, 3B and the box side surface 1A. The electric unit 4 is a partition plate 3A
Six support plates 3C are attached in the vertical direction between the electric unit 4 and the partition plate 3B to form an electric unit 4 stacked in six stages. A cable unit 5 is formed adjacent to both sides of each stacked electric unit 4. On the upper side of the electric unit 4 and the cable unit 5, an electric circuit unit is formed together with the bus unit 6, as shown in FIGS.

The bus unit 6 connects the vertical bus 8 of the three-phase power bus 7. The vertical buses 8 are arranged along the stacking direction of the six-stack electric unit 4. As the vacuum circuit breaker 20 moves within the electric unit, the vacuum circuit breaker 20 is electrically connected to and separated from the vertical bus 8 and the horizontal conductor 32. The three-phase horizontal conductor 32 is arranged between the electric unit 4 and the cable unit 5.
The electrical unit side end of the three-phase horizontal conductor 32 is connected to and separated from the vacuum circuit breaker 20, and the cable unit side end is connected to a load cable 43 via a cable head 38.

Each phase of the power supply bus 7 is arranged in the bus chamber in a direction orthogonal to the moving direction of the vacuum circuit breaker 20, and the power supply bus end of the electric unit is connected to one end of the vertical bus 8.

One end of the vertical bus bar 8 extends from above the electric unit toward the back of the box, is bent downward in the middle, and the other end extends in the direction of stacking of the electric unit 4. The vertical bus 8 is shown in FIG.
Is conductive member as shown in Figure is covered with the insulating sheath 8A, the dimensions of the thick portion L ₁ is using a strip conductor, i.e. busbar narrower dimensions than the width portion L _2. The width portion L ₂ is disposed in a direction opposite to the electric Yunitsuto 4, the vertical bus 8 is supported on the bus side insulating Yunitsuto 10.

Bus-side insulation unit 10 consists of electric unit 4 and box back 1B
And is supported by the partition plates 3A and 3B by fastening means such as screws, and is made of an insulating member such as an epoxy resin. As shown in FIGS. 6A and 7, the bus-side insulation unit 10 has a back surface corresponding to the back surface 1B of the box.
The periphery of 11 is surrounded by a side wall 12, and a connection unit 13 is formed inside.

The inside of the connection unit is partitioned by two inter-phase insulating barriers 12D to form three connection units 13. The upper and lower side walls 12A extend from the left and right side walls 12B and abut against the partition plate 3B, and the upper and lower side walls 12A are separated by the fastening means.
It is attached to.

The upper and lower side walls 12A and the left and right side walls 12B and the partition plates 3A, 3
A pressure release path (FIGS. 3 and 4) 14 surrounded by B and the back surface 1B of the box is formed. The pressure release passage 14 is provided on a part of the surrounding surface other than the left and right side walls 12B, for example, on
(Fig. 4). The closing plate 15 has a through hole formed in the box back surface 1B, and the through hole is closed by the closing plate. The closure plate normally closes the through hole with pressure and opens when the pressure in the pressure relief passage increases.

The mounting seat 16 provided on the back surface in the connection unit has a screw hole formed therein. The position of the mounting seat 16 is the connection unit 13
Are shifted upward from the center (or lower). Through holes 17 are formed in the upper and lower side surfaces 12A of the connection unit 13. The vertical bus bar 8 passing through the through hole 17 is mounted on the mounting seat 16 by a fastening means such as a screw. A part of the vertical bus bar 8 in the connection unit has the insulating jacket 8A removed to form the first fixed contact 18 exposing the conductive member. The first fixed contact 18 electrically contacts and separates from the first movable contact 21 of the vacuum circuit breaker 20. If the mounting seat 16 is displaced at the time of contact and separation, the vertical bus 8 between the through holes when the mounting seat 16 is not present is compared with the length dimension, and the vertical bus between the mounting seat 16 and the lower through hole 17 is compared. Since the size can be shortened, the first movable contact 21 is the first fixed contact.
There is an advantage that it is hard to be deformed by the pressing force when it comes into contact with 18.

The thickness portion L ₁ of the first stationary contact 18 first movable contact 21
If the the toward and away from, as compared with the width portion L ₂ to contact and separation on the first movable contact, the depth dimension shrinkage Dekiru small. The vacuum circuit breaker 20 will be described with reference to FIGS. 6 (c) and 7. The carriage 23 provided with the roller 23A has a circuit breaker-side insulating unit 24 made of an insulating member mounted thereon. In the unit, a shut-off section 25 composed of a three-phase vacuum valve is arranged horizontally. Depressed portions 27 are formed between the side walls 26 of the insulating unit between the cutoff portions. The recess 27 fits into the interphase insulating barrier 12D shown in FIG.

Although not shown, a pair of electrodes are arranged in the inside of the blocking portion 25, and a rod 25A extends from each electrode to the outside of the blocking portion. When one of the movable rods moves, the other electrode moves from one electrode to open and close. In general, the size of the vacuum circuit breaker in the direction of rod movement, that is, in the direction of opening and closing of the breaking portion, is longer than the height in the true angle direction. For example, the dimension between the opening and closing direction and the height direction of the blocking portion is about 3: 1.

Further, in the present invention, the breaking unit 25 is arranged so as to open and close in the same direction as the moving direction of the vacuum circuit breaker 20 in the electric unit. A first movable contact 21 and a second movable contact 22 are attached to a front end rod 25A and a rear end rod of the blocking portion 25. The first movable contact 21 comes into contact with and separates from the first fixed contact 18.
The second movable contact 22 extends above the first movable contact 21 and has a distal end opening in the depth direction, and comes into contact with and separates from the second fixed contact 31 shown in FIGS. 6 to 9. Second fixed contact 31
Are provided on the load-side disconnection unit 31.

When the first movable contact 21 and the second movable contact 22 are pulled out from the insertion side, the above-described embodiment is displaced upward and downward, and is disposed in the depth direction of the blocking portion 25. Although the dimensions are reduced, the same effect can be achieved by arranging them in left and right directions, that is, in a right angle direction or an oblique direction.

Further, in the present invention, the rod on the second movable contact side is moved so that the rod moving speed and the like can be easily adjusted from the door side.

The load-side disconnecting unit 30 is disposed between the electric unit 4 and the cable unit 5 and is supported between the partition plates 3A and 3B, and is configured as follows.

The three-phase horizontal conductors 32A to 32C are arranged in the electric unit 4 and the cable unit 5. Each horizontal conductor on the electrical unit side
32A to 32C connect the branch conductors 33A to 33C. The horizontal conductors 32A to 32C on the cable unit side are bent in the middle toward the door side to form projecting conductors 34A to 34C. These horizontal conductors 32, branch conductors 33, and projecting conductors 34 are covered with an insulating resin such as an epoxy resin to form a fixed-side insulating layer 35.

Three load connection units 36 are formed on the fixed side insulating layer 35 at locations corresponding to the second movable contacts 22. The second fixed contacts 31A, 31B, 31C are arranged in the load connection unit 36. Each of the fixed contacts 31A to 31C is formed at the tip of the branch conductor 33A to 33C, and has the same thickness as the first fixed contact 18.
Toward or away from the second movable contact 22 at L _1.

The cable room side of the fixed-side insulation layer 35 is shown in FIG.
As shown in (B), connecting portions 37 are provided at the tips of the projecting conductors 34A to 34C.
Is provided. Connection part 37 is an insertion plug type cable head
38 is inserted. The insertion plug type cable head 38 is molded with an insulating resin member such as insulating rubber to form an insertion-side insulating layer 39.

The conductive layer 40 covers the upper side of the lamination surface of the fixed-side insulating layer on the electric unit side and the left and right side surfaces in the longitudinal and depth directions. That is, the surface of the insulating layer not facing the second movable contact is covered with the conductive layer. The surfaces of the fixed-side insulating layer 35 and the insertion-side insulating layer 39 on the cable unit side are both insulating layers 35,
The other than the contact surface 39 is covered with a conductive layer 40. In addition, a conductive layer is provided on the entire surface of the fixed-side insulating layer 35 on the cable room side. The ground terminal 41 is grounded via a ground line 41A.
An insertion portion 42 is provided in the cable head, and the insertion portion 42 is connected to the load cable 43, and when the insertion portion 42 is inserted into the connection portion 37, between the fixed-side insulation layer 35 and the insertion-side insulation layer 39. Although the gap 100 is formed, the crossover 44 wound around each of the insulating layers 35 and 39 electrically connects the ground metal layer between both insulating layers,
The gap prevents the conductive metal layer 40 from being electrically interrupted, thereby preventing electric shock when the cable head 38 is attached or detached.
Instead of the crossover, a contact piece may be provided on one side of the insulating layers 35 and 39 to connect the ground layers.

The fixed-side insulating layer 35 includes a directional zero-phase current transformer 45 and a current transformer.
46 is attached detachably. The directional zero-phase current transformer 45 is a fixed insulating layer between the electric unit 4 and the cable unit 5.
Since it is located at 35, the split type is used.

 Next, the operation and effect of the switchboard of the present invention will be described.

(1) In the present invention, the moving direction of the vacuum circuit breaker 20 and the opening / closing direction of the breaking unit 25 are arranged in the same direction in the electric unit. For this reason, the height dimension of the vacuum circuit breaker 20 can be reduced to about 3/1 as compared with the case where the opening / closing direction of the interrupting section 25 is arranged in the height direction.

 Further, the reduction of the height dimension will be examined.

An insulator capacitance exists between the horizontal conductor 32, the branch conductor 33, the load cable 43, and the like, and the fixed-side insulating layer 35 and the insertion-side insulating layer 36 that are covered. The leakage current from each conductor charges the insulating capacitance. The charging current is the conductive layer 40 of the present invention,
Since the current flows to the ground via the ground line 41A, the potential difference is almost zero. For this reason, a charging voltage is hardly applied to the surface of the conductive layer 40, and a gap formed between the load-side disconnecting unit 30 and the support plate 3C and the top plate 3D is hardly needed. The gap in the stacking direction of the electric unit 4 and the cable unit 5 can be further reduced since a gap that does not hinder the entrance and exit of the vacuum circuit breaker 20 can be further reduced. Compared with the stacked switchboard, the switchboard of the present invention can reduce the center of gravity by the reduced size in the stacking direction, and can greatly improve the earthquake resistance. Further, the entire cable unit 5 can be reduced. Further, even if an operator comes into contact with the load-side disconnection unit 30, the electric power supply is safe without electric shock.

(2) In the present invention, both movable contacts 21 and 22 are fixed
The inter-phase insulating barrier 12D is fitted in the recess 27 while in contact with the base 31. As a result, the inter-phase creepage insulation distance between the first movable contacts 21 of each phase is significantly increased, and the width of the box body can be reduced.

(3) In this embodiment, FIGS. 2 and 9 (A) and (B)
Lateral conductor ends 32A to 3 arranged in the cable unit
Each phase of 2C is made to project the projecting conductor 34 toward the insertion port side, and each phase and the projecting conductor at the end of the horizontal conductor are covered with the insulating layer 35, and the insulating layer at the projecting conductor side is separated from the insulating layer at the horizontal conductor end. By projecting to the insertion port side to form irregularities, the creepage distance between adjacent projecting conductors is reduced, and the width of the cable unit is reduced, whereby the power distribution board can be reduced. In addition, since the projecting conductor 34 can protrude toward the insertion port side, if the door 2 is opened, since the door 2 is facing a passage or the like, a large work place can be taken, and the work can be easily performed.

In addition, when attaching and detaching the cable head 38 to and from the connection portion 37, since there is no potential difference between the fixed insulating layer 35 and the movable insulating layer 36, the operation can be performed safely without electric shock.

Further, the load cables 43 of this embodiment are respectively drawn out to the left and right sides of the six-stage electric unit 4 by three, and are distributed and arranged in the respective cable units 5, so that the load cables in the respective cable units are separated. 43 sequences reduced,
The work space inside the cable unit has been widened to facilitate the work of wiring the load cable 43.

Further, in this embodiment, when the worker attaches the directional zero-phase current transformer 45 and the current transformer 46 to the fixed-side insulating layer 35, the current transformers 45 and 46 are inserted into the fixed-side insulating layer 35. For example, each current transformer can be supported on the fixed-side insulating layer 35, so that the worker does not need to support each current transformer at the time of mounting, or a jig for supporting the current transformer as in the conventional case, and the assembly work is extremely easy. It has become. In this case, the zero-phase current transformer uses a split type, and in contrast to the conventional case where a zero-phase current transformer is attached to a load cable, in the present invention, the split-to-ground fault current provided on the fixed-side insulating layer 35 is reduced. The detection range can be widened.

(4) In this embodiment, the abnormal pressure when a flashover occurs due to the inability to shut off the inside of the wiring board is shown in FIGS.
Release pressure as shown. That is, when an ionized gas is generated due to a short circuit accident in the circuit breaker 20, the ionized gas P passes through the pressure release path 14, the closing plate 15 is opened like a dashed line, and the pressure is released to the outside, and the ionized gas P is supplied to the power source. By preventing the wraparound between the side insulation unit 10 and the back surface 1B of the box, a short circuit is prevented directly in the bus room 6 between the vertical buses, thereby preventing the spread of the accident.

In the above-described embodiment, the multi-stage switchboard is described. However, a normal non-stack switchboard may be used.

〔The invention's effect〕

As described above, the switchboard of the present invention can reduce the height dimension or the width dimension, so that the switchboard of the present invention has a reduced dimension in the stacking direction, compared to the switchboard when the conductive layer 40 is not used. The seismic resistance can be greatly improved. In addition, the work inside the switchboard can be done safely.

[Brief description of the drawings]

1 is a front view of a multi-stage switchboard shown as an embodiment of the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a view taken along the line III-III of FIG. FIG. 4 is a side view of FIG. 1, FIG. 5 is a circuit diagram showing an electric circuit of FIG. 1, and FIGS. First
FIG. 7 is an exploded perspective view showing a main part in the multi-stage switchboard shown in FIG.
FIG. 8 is a perspective view showing a main part near the power disconnecting part, and FIG.
(A) and (B) are a cutaway perspective view and a sectional side view when a part of the load-side disconnection unit is cut away and viewed. DESCRIPTION OF SYMBOLS 1 ... Box, 4 ... Electric unit, 6 ... Cable unit, 8 ... Vertical bus, 18 ... First fixed contact, 20 ... Vacuum breaker, 21 ... First movable contact, 25 …… Blocking part, 30…
... Load-side disconnection unit, 31 ... Second fixed contact, 38 ...
... cable head, 40 ... conductive layer, 43 ... load cable.

Claims (5)

(57) [Claims] An electric unit having at least two layers stacked in a housing, a cable unit formed on at least one side of the electric unit, and a three-phase power-supply-side bus arranged sequentially along a depth direction of the electric unit. And a three-phase load-side conductor having an insulating layer coated and insulated sequentially in the depth direction on the electric unit and the cable unit, and connected to ground on the upper side of the insulating layer of the electric unit. Switchboard comprising a coated conductive layer. 2. The switchboard according to claim 1, wherein connection portions for connecting to a circuit breaker and a load cable are provided on both sides of the load-side conductor. 3. The switchboard according to claim 1, wherein a zero-phase current transformer is provided in the conductive layer on the load side. 4. A bus-side insulating unit is provided by surrounding each phase disposed between the electric unit and the back surface of the housing with a side wall of an insulating member, and an opening is provided on a corresponding side of the electric unit of the bus-side insulating unit. The bus room of each phase having, and the power supply side bus extending vertically in the bus room, between the both side walls of the bus room and the partition plate on the side of the housing, and between the back of the bus room and the back of the housing The power distribution panel according to claim 1, wherein the pressure release path provided and the pressure in the pressure release path are exhausted by opening a closing plate provided on the back surface of the box. 5. A protruding conductor in which each phase of the load-side conductor disposed in the cable unit is turned halfway toward an insertion port side, and each phase of the load-side conductor is turned halfway to an insertion port side. The orientation is changed at different positions, and the phases of the projecting conductor are dispersed and directed toward the insertion port, the load-side conductor and the projecting conductor of each phase are covered with an insulating layer, and the projecting conductor-side insulating layer is 2. The switchboard according to claim 1, wherein the switchboard projects from the load-side conductor portion-side insulating layer toward the insertion port.