JPS5818827A - Gas breaker - 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 The present invention relates to a gas breaker in which a breaker in a grounded tank is surrounded by an insulating cylinder, and is particularly suitable for use in high voltage, large capacity systems. Regarding circuit breaker.

Gas circuit breakers using SF6 gas, which has excellent insulation and arc-extinguishing performance, are the mainstream of high-voltage, large-capacity circuit breakers, and buffer-type gas circuit breakers, which have a simple structure and high reliability, are attracting particular attention. .

However, in recent years, as the voltage and capacity of each breaker unit has increased, high-temperature gas that is ionized or dissociated by arc heat is released from the buffer device into the grounded tank when the current is cut off. However, a problem has arisen in that the dielectric strength between the high-potential interrupter and the grounded tank is reduced. In addition, there has been an increasing demand for improved reliability and cost reduction by improving unit breaking performance and reducing the number of series breaking points.

Against this background, there is a known technology in which the breaker where a large current arc occurs is surrounded by a container insulated from the grounded tank to prevent high-temperature gas from reaching the grounded tank after coming into contact with the arc. There is.

FIG. 1 shows the cut-off state of the two-point gas breaker. Inside the tank 1 at ground potential, there is an insulating tube 5 supported by a bracket 3 fixed to an insulating support 2 and an insulating support 4; A buffer breaker consisting of a contact 7, an insulating nozzle 8, a movable contact 9, a buffer cylinder 10, and a buffer piston 11 is housed, and the insulating nozzle 8 and movable contact 9 are removably attached to the buffer cylinder 1o with bolts. There is.

In the closed state, current flows from the terminal 13 supported in the air by the bushing 12, through the conductor 14, through the buffer cutoff section, and to the other terminal 13.

The shutoff operation is performed by driving the puffer device through the operating rod 15, insulator rod 16, link 17, and lever 18 using an operating device (not shown) placed at ground potential.

The grounding tank 1 is formed with an inspection opening 19 used when inspecting or replacing the contact 7.9, and this opening is sealed with a removable lid 2o.

According to such a configuration, high-temperature gas that contributed to arc extinguishment at the time of current cutoff is not released into the tank, so there is an advantage that a drop in the withstand voltage to ground can be prevented.

By the way, in the configuration in which the breaker is surrounded by an insulating cylinder, the first
As is clear from the figure, it is necessary to remove the insulating tube 5 when inspecting or replacing the contactor.

To remove the insulating tube 5, the insulating tube 5 must be removed from the bracket 3 and the insulating tube 5 must be taken out from the end of the grounded tank 1. Therefore, there is a problem that the disassembly and assembly work required to inspect or replace the contactor is time-consuming. A vessel was desired.

To deal with this, a method can be considered in which an inspection opening 21 is attached to the insulating cylinder 5 and this opening is formed so as to be sealed with a sealing member 22, as shown in FIGS. 2 and 3.

Since the sealing member is subjected to a pressure higher than the filling gas pressure caused by arc heat when a large current is cut off, mechanical strength is required. Metal materials generally have greater mechanical strength than insulating materials, so they have the advantage that the outer diameter of the insulating cylinder including the sealing member can be smaller than when formed of insulating materials.

However, when the sealing member 22 is made of a metal material, these sealing members, including the bolt 23 that fixes it to the insulating cylinder 5 and the embedded fitting provided in the insulating cylinder for screwing the bolt, are Since it is electrically insulated by the insulating cylinder, when a high voltage is applied, it becomes an uncertain potential with respect to the potential of the conductor in the cutoff part, and the electric field tends to concentrate in this part.

For this reason, it has been found that there is a drawback in that corona is generated near the bolts and embedded metal fittings, which deteriorates the insulation performance of the insulating tube itself and between the poles of the breaker section. Furthermore, if an electric field mitigation shield 24 is provided on the sealing member and the potential of the cutoff portion is applied to this shield, the uncertain potential can be eliminated and the electric field near the opening can be relaxed. There is a drawback that the insulation distance between the grounding tanks becomes small, reducing the withstand voltage to ground.

An object of the present invention is to form a member that stops bleeding at the opening of the insulating cylinder with an insulating material, eliminate the need to remove the insulating cylinder surrounding the breaker, facilitate inspection or replacement of the contact, and shorten the inspection time. Provide a gas breaker.

According to the present invention, an opening is formed in a portion of an insulating cylinder surrounding a breaker portion corresponding to a contact device, this opening is sealed with a removable insulating member, and the opening of the insulating cylinder is arranged in a tank. It is characterized in that it is disposed at a position corresponding to the sealable opening provided therein.

An embodiment of the present invention will be described below with reference to FIG. FIG. 4 shows a cross section of a main part of the structure for sealing the opening of the insulating tube.

As in the conventional structure, the insulating cylinder 5 surrounding the breaker part has an opening 25 formed in a portion corresponding to the contact, and this opening is provided with a protruding part 26, and a removable seal made of an insulating material is formed in the opening 25. A stopper member 27 is fixed to the protrusion 26 of the insulating cylinder 5 with an insulating bolt 28.

On the other hand, although not shown, an inspection opening is also provided in the grounded tank, and this inspection opening is provided at a position substantially corresponding to the opening 25 of the insulating cylinder 5. 29 is a handle.

In this configuration, the pressure generated by arc heat when a large current is cut off is received by the protruding portion 26 of the insulating cylinder 5, so that almost no pressure is applied to the insulating bolt 28. At the time of inspection, the bolts of the sealing member 27 are removed and the sealing member 27 is placed inside the insulating cylinder.

According to this embodiment, all the members that seal the inspection opening of the insulating cylinder are made of insulators, so there is no electric field concentration near the opening due to the sealing member, and there is no need to provide a shield for mitigating the electric field. There is no problem, and stable insulation performance between poles and ground can be obtained at all times.

As mentioned above, by forming a sealable opening in the insulating tube, there is no need to take the insulating tube out of the tank, making it easier to inspect or replace the contacts, and significantly reducing the time required to do so. can do.

FIG. 5 shows another embodiment of the invention. Fourth
The difference from the drawing is that a cylindrical insulating member 29f is provided to surround the insulating cylinder 5, and the opening 31 of the insulating cylinder 5 is sealed with this insulating member 29. When inspecting, by moving the insulating member 25 toward the end of the tank 1 (to the left in the figure), inspection can be performed through the opening 31 of the insulating cylinder 5. In this embodiment, since the insulating tube 5 has no protrusion, the insulating tube 5 can be manufactured easily. Furthermore, since the sealing member is an insulator, concentration of electric field between the interrupting portion electrodes can be eliminated. Furthermore, since the mechanical strength of the insulating member is increased, even if the wall thickness is increased, the ground insulation performance will not be reduced.

FIGS. 6 and 7 show still other embodiments of the present invention.

Figure 6 shows the circuit breaker during operation, and Figure 7 shows the circuit breaker during inspection. This is similar to FIG. 5 in that an insulating member 31 is provided to surround the insulating cylinder 5, and the opening 32 of the insulating cylinder 5 is sealed by the insulating member 31. The difference is that the insulating member 31
An opening 33 of the same size as the opening 32 of the insulating cylinder 5 is provided in the insulating cylinder 5, and by rotating the insulating member 31 in the circumferential direction during inspection, both openings are made to correspond to each other. In this embodiment, the same effect as in FIG. 5 can be obtained.

FIG. 8 shows still another embodiment of the present invention.

It is. The difference from the previous embodiment is that openings for inspection are provided at two locations. In this embodiment, inspection work can be carried out at two locations, which further reduces work time.

In the embodiments of the present invention described above, a two-point circuit breaker has been described, but the same effect can be obtained with a one-point circuit breaker.

According to the present invention, by configuring the member that seals the opening of the insulating cylinder with an insulating material, it becomes possible to eliminate an uncertain potential near the sealing member, and the insulating cylinder surrounding the breaker part can be removed. Since the contacts can be inspected or replaced without having to do anything, it is possible to provide a gas breaker with significantly reduced inspection and assembly time.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a conventional two-breath buffer type gas breaker, Fig. 2 is a partial sectional view of a conventional two-breath buffer type gas breaker, and Fig. 3 is a plan sectional view of the second figure. FIG. 4 is an enlarged sectional view of a main part of a gas breaker according to an embodiment of the present invention, FIG. 5 is a sectional view of a main part of a gas breaker according to another embodiment of the invention, and FIG. FIG. 7 is a cross-sectional view of a main part of a gas breaker according to another embodiment, FIG. 7 is a cross-sectional side view of FIG. 6, and FIG. 8 is a partial sectional view of a gas breaker according to another embodiment of the present invention. 1...Tank, 5...Insulating cylinder, 7,9...Contactor, 25th 5th design

Claims (1)

[Claims] 1. A buffer breaker having a detachable contact in a tank filled with insulating gas and a buffer device that blows compressed gas to extinguish the arc in conjunction with one of the contacts;
Comprised of an insulating tube surrounding the buffer cutoff section,
In the gas breaker, a sealable inspection opening is formed at a position corresponding to the contactor of the insulating cylinder, and at least one opening is provided at a position corresponding to the inspection opening of the insulating cylinder, and the opening 1. A gas breaker, characterized in that the insulating tube is releasably sealed with an insulating sealing member, and the opening of the insulating cylinder is disposed at a position corresponding to the inspection opening of the tank.