JP4625721B2 - Switchgear - Google Patents

Description

The present invention relates to a switchgear that can improve the voltage sharing of each vacuum valve connected in series.

Some conventional switchgears of this type improve the rated voltage of the switchgear by connecting in series two vacuum valves having a pair of contactable contacts. In order to make the voltage sharing of each vacuum valve equal, a capacitor connected in parallel is known (for example, see Patent Document 1).

In addition, when these vacuum valves are configured with air insulation, the overall shape becomes large, so that these are molded with an insulating material to reduce the overall shape (for example, see Patent Document 2). .)
Japanese Patent Laid-Open No. 10-12459 (pages 4-5, FIG. 9) JP 2002-152930 A (Page 9, FIG. 1)

  The above conventional switchgear has the following problems.

When vacuum valves are connected in series, the connection point between the main circuit potential (100%) and the ground potential (0
%) And intermediate potential. This intermediate potential is determined by the capacitance ratio formed by each vacuum valve and is less than 50%. This is because the capacitance of the vacuum valve on the load side (grounding side) becomes larger than that on the power source side due to the addition of the ground capacitance. As a result, the shared voltage of the vacuum valve on the power supply side increases. In particular, in the case where an insulating material is molded around the vacuum valve, the capacitance ratio tends to increase, and the shared voltage of the vacuum valve on the power supply side increases.

For this reason, the vacuum valve on the power source side has to be increased in size by increasing the distance between the contacts to increase the insulation performance.

On the other hand, in the case where a capacitor is connected in parallel to a vacuum valve, the capacitance must be large without depending on the capacitance ratio described above, and the capacitor itself becomes large, and the overall shape of the switchgear is accordingly increased. It was getting bigger.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a switchgear that can equalize the voltage sharing of the vacuum valves connected in series and reduce the overall shape.

In order to achieve the above object, a switchgear according to the present invention includes a first switchgear formed by molding a first insulating layer by molding a vacuum valve having a pair of contactable and separable contacts with an insulating material. A second opening / closing part in which a third insulating layer is formed by molding an insulating material around a vacuum valve similar to the vacuum valve, and the first opening / closing part and the second opening / closing part are connected in series. A connecting conductor portion formed by molding an insulating material around the connecting conductor to form a fifth insulating layer, and an operation mechanism coupled to each of the first opening portion and the second opening portion. The connection conductor has a square cross section .

ADVANTAGE OF THE INVENTION According to this invention, the shared voltage of a 1st switch part and a 2nd switch part can be improved , and the whole shape of a switch apparatus can be reduced in size.

  Embodiments of the present invention will be described below with reference to the drawings.

First, a switchgear according to Embodiment 1 of the present invention will be described with reference to FIG. 1 is a cross-sectional view illustrating a configuration of a switchgear according to Embodiment 1 of the present invention.

As shown in FIG. 1, the opening / closing device includes a first opening / closing part 1a, a second opening / closing part 1b, and a fixed-side connecting conductor part 1c that connects the first opening / closing part 1a and the second opening / closing part 1b in series. It consists of

The first opening / closing part 1a is provided with a vacuum valve 2 having a pair of contacts that can be contacted and separated. Further, a first insulating layer 3 formed by molding an insulating material such as an epoxy resin is provided around the vacuum valve 2. On the movable side of the vacuum valve 2 shown below, the first
A contact conductor 5 that makes sliding contact with the outer conductor 4, an insulating operation rod 6, and an operation mechanism 7 such as an electromagnetic actuator are connected to open and close the pair of contacts.

The first outer conductor 4 serving as one main circuit is provided with a second insulating layer 8 formed by molding an insulating material such as an epoxy resin. One of the second insulating layers 8 is
The interface is connected to the first insulating layer 3 via a flexible insulator (not shown), and the other is fixed to the operation mechanism 7 side.

The second opening / closing part 1b is provided with a vacuum valve 9 having a pair of contact points that can be separated from each other and have the same diameter, axial length, and the like as the vacuum valve 2 of the first opening / closing part 1a. The vacuum valve 9
Around this, a third insulating layer 10 formed by molding an insulating material such as an epoxy resin is provided. On the movable side below the vacuum valve 9, a contact conductor 12 that makes sliding contact with the second outer conductor 11, an insulating operation rod 13, and an operation mechanism 14 such as an electromagnetic actuator are connected. The contacts are opened and closed.

The second outer conductor 11 serving as the other main circuit is provided with a fourth insulating layer 15 formed by molding an insulating material such as an epoxy resin. One of the fourth insulating layers 15 is interface-connected to the third insulating layer 10 via a flexible insulator (not shown), and the other is fixed to the operation mechanism 14 side.

The fixed-side connection conductor 1c is provided with a U-shaped and circular cross-section fixed-side connection conductor 16 that connects the upper fixed sides of the vacuum valves 2 and 9 in the drawing. Further, the fixed side connection conductor 16
Around this, a fifth insulating layer 17 formed by molding an insulating material such as an epoxy resin is provided. The main circuits at both ends are interface-connected to the first opening / closing part 1a and the second opening / closing part 1b via a flexible insulator (not shown). The fifth insulating layer 17
The insulation thickness is a predetermined thickness that can withstand the rated voltage.

Here, the fifth insulating layer 17 is formed of an insulating material having a dielectric constant smaller than that of the first insulating layer 3 and the third insulating layer 10. That is, the filling amount of a filler such as hydrated alumina filled in the epoxy resin is reduced. Generally, the dielectric constant ε of epoxy resin is ε = 5
On the other hand, when the filling amount of the filler is reduced, ε = 3 to 4 can be obtained.

For this reason, the electrostatic capacitance formed between the fixed connection conductor portion 1c and the ground is the first opening / closing portion 1a.
And it becomes smaller than the 2nd opening-and-closing part 1b. Note that the second insulating layer 8 and the fourth insulating layer 15 are formed of the same insulating material as the first insulating layer 3 and the like.

When the first outer conductor 4 is on the power source side, the second outer conductor 11 is on the load side, and both vacuum valves 2 and 9 are opened, the capacitance of the fixed-side connecting conductor portion 1c is the first opening and closing. Since it becomes smaller than the part 1a and the 2nd opening-and-closing part 1b, the shared voltage of the 1st opening-and-closing part 1a and the 2nd opening-and-closing part 1b can be equalized. That is, the potential of the fixed-side connection conductor 16 approaches 50%, and the shared voltage applied between the contacts of both the vacuum valves 2 and 9 can be equalized. Moreover, the insulation performance of both the vacuum valves 2 and 9 can be made the same.

Even when the first outer conductor 4 is on the load side and the second outer conductor 11 is on the power source side, the shared voltage applied between the contacts of the vacuum valves 2 and 9 can be equalized.

According to the switchgear of the first embodiment, the capacitance of the fixed connection conductor 1c that connects the first switch 1a and the second switch 1b in series is set to the first switch 1a and the second switch 1b. Since it is made smaller than the opening / closing part 1b, the shared voltage applied between the respective contacts when both the vacuum valves 2 and 9 are opened can be equalized, and the overall shape can be reduced in size.

In the first embodiment, the first insulating layer 3, the third insulating layer 10, and the fifth insulating layer 17 are used.
The fifth insulating layer 17 may be formed by molding the whole with a flexible material such as silicon rubber having a dielectric constant smaller than that of the epoxy resin. In this case, a flexible insulator for interface connection becomes unnecessary.

Further, the fifth insulating layer 17 may have a thickness greater than or equal to a predetermined insulating thickness. Thereby, the electrostatic capacitance which the fixed side connection conductor part 1c forms can be made small.

Next, a switchgear according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 2 is a cross-sectional view illustrating a fixed-side connection conductor portion of the switchgear according to Embodiment 2 of the present invention. The second embodiment is different from the first embodiment in the insulating layer. In FIG. 2, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 2, a sixth insulating layer 20 formed by, for example, heating and foaming an epoxy resin in the air or in an insulating gas is provided around the fixed-side connection conductor 16. The ratio of foaming is 1.5 times, and the insulating thickness is increased by the ratio of foaming as compared with Example 1.

If the ratio of foaming is 1.2 times or less, the capacitance formed between the fixed-side connecting conductor portion 1c and the ground cannot be greatly reduced, and if it is 3 times or more, the sixth insulating layer 20 This is not preferable because the dielectric strength is greatly reduced.

Thereby, since the dielectric constant of the sixth insulating layer 20 is small and the insulation thickness is increased, the capacitance formed between the fixed-side connecting conductor portion 1c and the ground can be reduced.

  According to the switchgear of the second embodiment, the same effects as those of the first embodiment can be obtained.

Next, a switchgear according to Embodiment 3 of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view illustrating the fixed-side connection conductor portion of the switchgear according to Embodiment 3 of the present invention. The third embodiment is different from the first embodiment in the shape of the fixed side connecting conductor. In FIG. 3, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 3, the fixed-side connection conductor 21 has a square cross section. When the cross-sectional area of the fixed-side connecting conductor 21 is constant and the lengths of one side and the other side are changed, the surface area becomes the smallest in a square cross-section having the same length on the one side and the other side. Thereby, since the surface area of the fixed-side connection conductor 21 can be reduced without changing the energization capacity, the capacitance formed between the fixed-side connection conductor portion 1c and the ground can be reduced. The corner portion has a slight curvature to relieve stress during molding.

  According to the switchgear of the third embodiment, the same effect as that of the first embodiment can be obtained.

Next, a switchgear according to Embodiment 4 of the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view illustrating the fixed-side connection conductor portion of the switchgear according to Embodiment 4 of the present invention. The fourth embodiment is different from the first embodiment in the shape of the fixed side connecting conductor. In FIG. 4, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 4, the fixed-side connection conductor 22 has a configuration in which a plurality of conductors are bundled. The cross-sectional shape of the conductor may be round or polygonal. Thereby, since an energization current can be flowed effectively by the skin effect, the surface area can be made smaller together with the cross-sectional area than that of a single wire.

  According to the switchgear of the fourth embodiment, the same effect as that of the first embodiment can be obtained.

Next, a switchgear according to Embodiment 5 of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view illustrating a configuration of a switchgear according to Embodiment 5 of the present invention. The fifth embodiment is different from the first embodiment in the attachment position of the connection conductor. In FIG. 5, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in FIG. 5, the opening / closing device includes a first opening / closing part 1a, a second opening / closing part 1b, and a first opening / closing part 1a and a second opening / closing part 1b connected in series between the movable sides below the figure. The movable side connecting conductor portion 1d is configured.

The movable side connection conductor portion 1d has a movable side connection conductor 2 in which the contact conductors 5 and 12 are in sliding contact with each other.
3 is provided. Around the movable side connection conductor 23, the first insulating layer 3, the third insulating layer 1
A seventh insulating layer 24 formed by molding an insulating material such as an epoxy resin having a dielectric constant smaller than 0 is provided. Both ends of the main circuit of the movable side connecting conductor portion 1d are interface-connected to the first opening / closing portion 1a and the second opening / closing portion 1b via a flexible insulator (not shown).

Also, one main circuit molded with the same insulating material as the first insulating layer 3 and the third insulating layer 10 on the fixed side above the first opening / closing portion 1a and the second opening / closing portion 1b in the figure. And a fourth outer conductor 26 serving as the other main circuit are provided in an interface connection.

As a result, the capacitance formed by the movable-side connecting conductor portion 1d between the ground and the ground decreases, and the first
The shared voltage between the open / close portion 1a and the second open / close portion 1b can be equalized. The seventh insulating layer 24 may be made of foam insulation as in the second embodiment, and the movable side connection conductor 23 is formed in a square cross section as in the third embodiment, and a plurality of conductors as in the fourth embodiment. A bundled configuration may be used.

According to the switchgear of the fifth embodiment, the same effect as that of the first embodiment can be obtained even when the movable sides of the vacuum valves 2 and 9 are connected to each other.

In addition, this invention is not limited to the said Example, In the range which does not deviate from the summary of invention, it can implement in various deformation | transformation. In the above embodiment, the main circuit device is described by molding the insulating material to form only the insulating layer. However, the vacuum valves 2 and 9 are connected to each other even when the ground layer is provided on the surface of the insulating layer. If the capacitance of the connecting conductor portion is reduced, the shared voltage can be equalized.

Even in the case where capacitors that are connected in parallel with the vacuum valves 2 and 9 are embedded in the first insulating layer 3 and the third insulating layer 10, if the capacitance of the connecting conductor portion is reduced, the shared voltage is reduced. Can be equalized.

Sectional drawing which shows the structure of the switchgear which concerns on Example 1 of this invention. Sectional drawing which shows the stationary-side connection conductor part of the switchgear which concerns on Example 2 of this invention. Sectional drawing which shows the stationary-side connection conductor part of the switchgear which concerns on Example 3 of this invention. Sectional drawing which shows the stationary-side connection conductor part of the switchgear which concerns on Example 4 of this invention. Sectional drawing which shows the structure of the switchgear concerning Example 5 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a 1st opening / closing part 1b 2nd opening / closing part 1c Fixed side connection conductor part 1d Movable side connection conductor part 2, 9 Vacuum valve 3 1st insulating layer 4 1st outer conductor 5, 12 Contact conductor 6, 13 Insulation Operating rods 7, 14 Operating mechanism 8 Second insulating layer 10 Third insulating layer 11 Second outer conductor 15 Fourth insulating layers 16, 21, 22 Fixed side connecting conductor 17 Fifth insulating layer 20 Sixth Insulating layer 23 Movable connection conductor 24 Seventh insulating layer 25 Third outer conductor 26 Fourth outer conductor

Claims (1)

A first opening / closing part formed by molding a first insulating layer by molding an insulating material around a vacuum valve having a pair of contactable contacts;
A second opening / closing part formed by molding a third insulating layer by molding an insulating material around a vacuum valve similar to the vacuum valve;
A connection conductor portion formed by molding an insulating material around a connection conductor connecting the first opening and closing portion and the second opening and closing portion in series; and
An operating mechanism coupled to each of the first opening and closing part and the second opening and closing part,
A switchgear characterized in that the connecting conductor has a square cross section .

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