JPS61135016A - Vacuum switchgear - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vacuum switchgear in which an intermediate shield is provided surrounding an electrode.

[Conventional technology]

FIG. 9 is an Fr side view showing the configuration of a conventional vacuum switchgear of this type, as disclosed in, for example, Japanese Utility Model Publication No. 54-8354. In the figure, [υ is a vacuum switch tube, made of glass,
It is composed of a cylindrical insulating container (2) made of ceramic or the like, a fixed end plate (3), and a movable end plate (4).

(5 bars 6) are a fixed electrode and a movable electrode, respectively, which are arranged coaxially and removably in the vacuum switch tube (1). Fixed 1! The box (5) is fixed to the fixed side end plate (3) by passing through the fixed side end plate <'a), and the movable electrode (6) is fixed to the bellows by passing through the town (7) It is attached to the movable end plate (4) through the gate and has a slidable structure. (8) is a cylindrical intermediate shield that surrounds the fixed electrode (5) and the movable electrode (6). The insulation capacity is
(2) K is installed.

FIG. 9 shows an open state. During a fault current cutoff operation, the movable electrode (6) is opened by sliding by a masterpiece mechanism (not shown), and an arc (9) is generated between the fixed electrode (5) and the movable electrode (6). Eventually, at the same time as the current reaches zero, the ions and neutral particles made of electrons or metal vapor that had been maintaining the arc (9) are blown into the vacuum at high speed (Buddhist particles), and the fixed electrode (5) ) is captured and adsorbed to the surface of the movable i4 box (6) and the surface of the intermediate shield (8), and the fixed electrode (5) and the movable ffl
(6) Successful disconnection is achieved by quickly recovering the dielectric strength between the two.

In this way, in conventional vacuum switchgear, the intermediate shield (
8) Improvement of the electric field silo in the vacuum switch tube (1),
In addition to preventing the adhesion of ions and neutral particles such as metal vapor diffusing from the arc (9) to the insulating container (2), it is also important for catching and adsorbing the diffused particles at the zero current point. plays a role. Generally, the higher the cooling capacity of the intermediate shield (8), the greater the trapping and adsorption effect of the diffused particles. Further, the temperature of the intermediate shield (8) itself increases as a result of the above-mentioned diffusion particles being captured by the igIL.

[Problems to be solved by invention E] With the intermediate shield of the conventional vacuum switchgear as described above, when fault current is cut off continuously, if the heat capacity of the intermediate shield is insufficient, ilP due to accidental current cutoff! The second accidental current cut-off must be carried out before the intermediate shield has cooled down sufficiently, and as the temperature of the intermediate shield increases, the ability to capture and adsorb diffused particles decreases. This caused a delay in insulation recovery after the current zero point, which was likely to lead to re-ignition and failure of breaker. Also, to increase the heat capacity and cooling capacity of the intermediate shield.

Countermeasures have been taken in the past, such as thickening the intermediate shield and using materials with high thermal conductivity, but there are problems such as the size of the device itself to obtain sufficient effects.

This invention was made in order to solve this problem. Sufficient heat capacity and cooling capacity can be obtained without increasing the size of the intermediate shield, and even when repeated accidents occur, such as flushing or disconnection, the initial The purpose of the present invention is to provide a vacuum opening (1) device that can maintain the trapping and adsorption effect of diffused particles and has stable breaking performance.

[Ninth means for solving the problem] True'2I according to this invention! The closing device is sealed inside the intermediate shield! I! As a precaution, a cooling medium is sealed in this hollow part.

[Effect]

In this invention, the heat input to the intermediate shield due to the fault current is converted to evaporation ah by evaporating the cooling medium sealed in the hollow part inside the intermediate shield, so the temperature of the intermediate shield increases. is suppressed, and even if the fault current is cut off continuously, the adsorption ability of the diffused particles in the intermediate shield will not deteriorate, and as a result, insulation recovery will be performed quickly and stable breaking performance f@ can be obtained. .

Embodiment of the invention C] FIG. 1 is a sectional view showing an embodiment of the invention (1)
~(The force is exactly the same as the above conventional device. (1
0) is a cylindrical intermediate shield, inside of which is provided a sealed hollow part (11), in which a phase-changeable cooling medium (12) is sealed.

In the vacuum switchgear which has been exposed to heat as described above, the heat input entering the intermediate shield (10) at the time of fault current interruption is converted into the latent heat of vaporization of the cooling medium (12). ), and as a result, even if the fault current is cut off continuously, the intermediate shield (10) will not be able to capture or absorb the diffused particles. −
It is possible to provide a vacuum breaker that has quick insulation recovery after current zero point and stable breaking performance, although the effectiveness is often degraded.

The substance used as the cooling medium (12) varies depending on the usage status of the vacuum breaker, the breaker capacity, etc., but the cooling medium (12) is in a liquid phase during steady operation, and evaporates due to the temperature rise when the fault current is interrupted. It is only necessary to select the gas phase so that it becomes a gas phase. Typical examples are shown in Table 1. Although not shown in Table 1, the cooling medium may be selected from fluorocarbon-based cooling media sold by various manufacturers.

%1 table Substance value of cooling medium Figure 2 shows another embodiment of this invention in which the sealed hollow part (11) provided inside the intermediate shield (lO) is divided into a plurality of parts, and the machine of the intermediate shield (lO) Effects such as improved target strength and separation of clearing areas can be obtained. The other functions are the same as in the case of FIG. 1, and the temperature rise of the intermediate shield (10) can be suppressed by the latent heat of evaporation of the cooling medium (12).

FIG. 3 shows another embodiment of the present invention, in which the cross-sectional shape in the same direction is circular! A plurality of &1S(11) are provided.

Figures 4 to 11 show other embodiments of the present invention in which the bridge portion of the intermediate shield (lO) is made thinner and a hollow portion (11) is provided in the center. Figure 4 is inside! i! Department (
11) t-1 pieces. Figure 5 shows the hollow part (
11) The fc intermediate shield (10) is divided into three parts in a direction perpendicular to the axial direction. FIG. 6 shows a structure in which a plurality of hollow portions (ll) f each having a circular cross-sectional shape in the same direction are provided. Figures 7 and 8 are inside? ! The part (11) is divided into four parts in the axial direction of the intermediate shield (lO). In FIGS. 9 and 10, a plurality of hollow portions (11) each having a circular cross-sectional shape in the axial direction of the intermediate shield (lO) are provided.

[Young fruit of invention]

As explained above, this invention has a configuration in which a tightly closed space is provided inside the intermediate shield and a cooling medium is sealed in it, so that it is possible to obtain cooling capacity without increasing the size of the intermediate shield, and to prevent 4i-fault current and disconnection. Since the temperature rise of the intermediate shield during operation can be suppressed, it is possible to obtain a vacuum switchgear with stable interrupting performance even when fault current is interrupted continuously.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of one embodiment of this invention, Fig. 2 is a new music diagram of the main part of another embodiment of this invention in which the hollow part is divided into four vertically, and Fig. 3 is a sectional view of the 22nd part of the inside. 4 to 1 are cross-sectional views of main parts of other embodiments of the present invention having a circular annular shape;
Figure 0 shows an intermediate shield used in another embodiment of the present invention in which the ends of the intermediate shield are made thinner, and Figure 4 shows the middle shield. ! !
The section is l
Figure 6 is a cross-sectional view of the hollow part with a circular cross-sectional shape, Figure 7 is a cross-sectional view of the hollow part divided into four parts in the vertical direction, and Figure 8 is a cross-sectional view of the hollow part divided into four parts in the vertical direction. 9 is a cross-sectional view of the hollow portion having a circular rod-like cross-sectional shape. FIG. 10 is a sectional view taken along line X-X@ in FIG. 9, and FIG. 11 is a sectional view of a conventional vacuum switchgear. In the diagram, (2) is an insulated container, (3) is a fixed lateral board, and (4)
is the movable end plate, (5) is the fixed electrode, (6) is the fixed electrode,
(10) is an intermediate electrode, and (11) is a hollow part. Note that the same reference numerals in each figure indicate the same or equivalent parts. Agent Masu Oiwa Figure 1 fZ: 41 pH 4, No 5 Figure 6 Figure 11

Claims (1)

[Claims] 1) A cylindrical insulating container, a pair of end plates with both ends of the insulating container sealed, a pair of electrodes penetrating each end plate and arranged coaxially and removably inside the insulating container; A vacuum switchgear comprising: an intermediate shield having a sealed hollow section arranged in the insulating container so as to surround an electrode; and a cooling medium that is housed in the hollow section of the intermediate shield and whose phase changes depending on the temperature.