JPH0334168B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grounded tank-type breaker with a resistor.

Particularly in ultra-high-pressure breakers, a closing resistance is used to suppress surges during re-turning, and a break resistance is used to suppress surges during breaks. In this case, since the resistor occupies a very large volume, how to arrange it is an important issue.

Hereinafter, a detailed description will be given based on the drawings.

Figure 3 shows, for example, Mitsubishi Electric Technical Report Volume 44 (Showa 45).
2006) No. 9, page 1160, a closing resistor is used to suppress the surge that occurs when closing in ultra-high voltage switches such as 500KV.

In the figure, 1 is a grounded tank filled with SF ₆ gas as an insulating and extinction medium. 2 is a main contact, and is provided with a pair of main movable contacts and a main fixed contact in SF ₆ inside an insulating cylinder. Reference numeral 3 denotes a resistance contact, which includes a pair of resistance movable contact and a resistance fixed contact in SF ₆ inside an insulating cylinder. Usually, the main contactor 2 and the resistance contactor 3 are collectively referred to as an isolation chamber. Reference numeral 4 denotes a support for supporting these contacts, and this is supported by an insulator 5 provided to protrude from the ground tank 1. 6 is a resistor. In this example, it is formed into a single inverted L-shape, one end of which is fixed to the tip of the resistance contact 3, and the other end connected to the main contact 2 through a conductor 7. The axes of the main contactor 2, resistance contactor 3, and resistor 6 are located at different positions vertically and backwards from the plane of the drawing, and the resistors in the center (looks like a T-shape) also collide with each other. Never. 8 is the part such as resistor 6,
This is a cylindrical shield for mitigating the electric field provided to the grounded tank 1 so as to obtain good insulation properties using SF ₆ . A connecting conductor 9 connects the main contact 2 and the conductor 11 fixed to the adjacent main contact 2 or the insulating spacer 10. 12 is a capacitor for improving potential distribution. In addition, this shiya disconnector is
Due to the operation of the operating mechanism, when the main contact 2 is turned on, the resistance contact is closed 10 ms before the main contact 2 is turned on, and the resistor 6 is energized for 10 ms. When the resistance contact 3 opens quickly and the main contact 2 then breaks the resistance, the resistor 6
No current flows through it.

With such a structure, it is possible to suppress the surge when the no-load power transmission line is turned on, and it is possible to reduce the withstand voltage value of the power transmission equipment.

In Japan's 500KV circuit breakers, a value of about 1000Ω is most suitable for the resistor 6 used at this time, and even if four arc extinguishing chambers are connected in series, the resistance at one point is 250Ω (1/4 of 1000Ω) is used. As shown in Figure 3, this resistor 6 is formed into an inverted L-shape with a total length of about 1 m, and a cylindrical shape with a diameter of 10 cm, which is bent at the center, and its weight is about 1 m.
It is about 30Kg. Therefore, even if the resistor 6 is fixed and supported at the tip of the resistance contact 3, it can withstand sufficient resistance, the volume occupied by the resistor 6 is small, and insulation problems are relatively easy to solve. However, for higher voltage 1000KV sheath breakers, a sheath breaker is also required to suppress surges when the sheath breaks. At this time, a resistance of about 500Ω is required for the connection and disconnection, but 500Ω is also sufficient for the connection for 1000KV. Therefore, the resistance contact 3 is shared to simplify the structure, and the resistance for the input and disconnection is simplified. It is convenient to share the same resistor.

Normally, a resistor is inserted for 10ms when it is turned on, and for 30ms when it is turned off. Therefore, when sharing, if you perform a series of operations such as turning on and turning off,
The time during which current flows is four times longer than when it is only turned on. Also, the voltage is doubled from 500KV to 1000KV, and the resistance is halved from 1000Ω to 500Ω. Therefore, the amount of heat generated = (time for current to flow) x (voltage)
Since there is a relationship of ² /(resistance), when turning on and cutting off continuously, the ratio of heat generation amount of 1000KV to 500KV is 32 (=4×2 ² /1/2) times.

On the other hand, ultra-high voltage breakers can be handled by changing the number of arc extinguishing chamber units connected in series depending on the voltage.
At 1000KV, there are twice as many units, so the amount of heat generated by the resistor per unit is 16 times as large. resistance is
Heat is generated by the current for a short time of 10ms or 30ms, and there is almost no heat dissipation during this time, and on the other hand, there is a permissible temperature for the resistor. Therefore, 16 times the heat capacity,
In other words, a resistor 6 having 16 times the weight and volume is required.

The surge suppression resistor 6, which has such a large weight, is installed to withstand vibrations during earthquakes and transportation, and in addition, the resistor 6 occupies a very large volume and has the ability to carry a large current at all times. In order to provide the large-sized connecting conductor 9 in the grounded tank 1 as small as possible while maintaining excellent withstand voltage characteristics, the arrangement thereof is an important issue.

The present invention has been made in view of the above, and provides a tank-shaped shield breaker having excellent mechanical, electrical, and thermal characteristics with such a large resistor. It is something to do.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows a half of a shingle disconnector embodying the present invention in a cross section parallel to the tank axis. The right half from point A also has a structure symmetrical to this figure (the left half of point A). Further, FIG. 2 is a cross-sectional view taken from - in FIG. 1. In the figure, 1 is a grounded tank filled with SF ₆ gas as an insulating and extinction medium. 2
is a main contact, which is composed of a main movable contact 2a and a main fixed contact 2b. Reference numeral 3 denotes a resistance contact, which is composed of a resistance movable contact 3a and a resistance fixed contact 3b. 13 is a support that supports each of the movable contacts 2a and 3a, 14 is a support metal fitting that supports the main fixed contact 2b, and 15 is a support metal fitting that supports the resistance fixed contact 3b. These support fittings 14 and 15 are the insulator 1
6 and 17, respectively, to the support 13. The support body 13 is an insulating cylinder (first insulator) 1
8 and is supported from the ground tank 1. The main movable contact 2a connects the link mechanism 19 to the resistance movable contact 3.
a is connected to an operating mechanism 22 via link mechanisms 20 and an insulated operating rod 21 to be driven. A plurality of resistors 23 are assembled into rod shapes and arranged concentrically with the ground tank 1 as shown in FIG. 24 is a supporting metal fitting, and 25 is a shield for mitigating an electric field. In addition,
23 to 25 constitute a surge suppressor 26.
A cylindrical second insulator 27 supports the suppressor 26, and is fixed to the tank 1 so as to protrude from the ground tank 1.
A connecting conductor 28 connects the resistor 23 and the fixed resistance contact 3b, and is flexible. 29 is an insulating spacer that connects to adjacent equipment and serves as a gas barrier. 30 is a connection conductor that connects the main fixed contact 2b to the insulating spacer 29. This connecting conductor 30 has a cylindrical shape and is arranged in the center of a group of resistors 23 arranged concentrically with a required insulation distance, and both ends are connected by a sliding contact 32.
33 is a metal fitting that connects one end of the resistor 23 to the connection conductor 30. 35 is a capacitor for improving potential distribution.

With the above structure, even if the resistor 23 is heavy, it is supported by a dedicated support tube 27 with sufficient strength, so it has a mechanical structure that can withstand earthquakes or vibrations during transportation. You can gain strength. The resistors 23 are arranged concentrically around a large circular connecting conductor 30 at a predetermined distance, so that the resistors 23
3 and the connecting conductor 30, and between the resistor 23 and the grounding tank 1, good withstand voltage performance is obtained, and
Large current carrying capacity can be obtained thermally.

Furthermore, since the surge suppressor 26 is supported by the insulator 27 fixed to the grounding tank 1, the space between the surge suppressor 26 (corresponding to the resistor 6 in the conventional example) and the resistance contact (supporting metal fitting) 15 is flexible. It becomes possible to connect the flexible connecting conductor and the connecting conductor 30 with a sliding contact, and dimensional errors between them can be easily adjusted and assembly is easy.

FIG. 4 shows an example in which the resistor 23 has a bent structure and is arranged on the circumference. In the figure, 34 is a resistance assembly fitting, 35 is a spacer made of an insulator,
36 is a terminal board, which is connected to a contact or the like. With this structure, the resistor 23 becomes a short block, so the length of the entire shield breaker can be shortened.

Here, we have explained the case of one type of resistor, but it is also possible to use two-stage resistors with high and low resistance values, separate resistors for breaking and closing, and adding resistance contactors for each. A similar configuration can be used.

As described above, according to the present invention, a pair of main contactors, a resistance contactor, and a surge suppressor, which are provided in series and adjacent to each other in a grounding tank, are connected to the first and second contacts, which are fixed and protrude from the grounding tank, respectively. Fixedly supported by an insulator, the surge suppressor has a structure in which multiple rod-shaped resistors are arranged on the circumference, and a connecting conductor that is connected to a sufficiently large main contact is provided at the center of the circumference. Therefore, it is possible to use a surge suppressor that weighs an order of magnitude more than a conventional 500KV closing resistor, such as a 1000KV surge suppressor that doubles as a closing resistor and a disconnection resistor. It has sufficient mechanical strength to withstand earthquakes and vibrations during transportation, has few areas where the electric field concentrates, relaxes the electric field, has good withstand voltage performance, and generates little heat when normally energized, allowing it to carry large currents. You can get a suitable cutter.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the shingle breaker according to the present invention, FIG. 2 is a cross-sectional view taken along the line - in FIG. 1, and FIG. 4
The figure is a sectional view showing a main part of another embodiment of the invention. In the figure, 1 is a ground tank, 2 is a main contact,
3 is a resistance contact, 18 is a first insulator, 24 is a supporting metal fitting, 26 is a surge suppressor, 27 is a second insulator, and 30 is a connecting conductor.

Claims (1)

[Claims] 1 A first series body is constructed by connecting a main contact and a connecting conductor in series in a grounded tank filled with insulating gas, and a surge suppressor and a resistance contact are connected in series. In a circuit breaker in which a second series body is connected in parallel with the first series body, the main contact and the resistance contact are supported by a common support, and this support is connected to the ground tank. The surge suppressor includes a plurality of rod-shaped resistors that protrude inside and are fixedly supported by a first insulator that is fixed to the grounding tank and arranged in parallel, and support fittings that are fixed to both ends of the resistors. a plurality of rod-shaped resistors constituting the surge suppressor, the surge suppressor protruding into the ground tank and fixedly supported by a second insulator fixed to the ground tank; 1. A wire disconnector characterized in that the connecting conductor is arranged in the center of the container.