JPH0754904Y2 - Gas circuit breaker for shunt reactor - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial field of application) The present invention provides a device suitable for opening and closing a large-capacity reactor connected to a shunt reactor connected to a transmission system of 168 kV to 300 kV class. A gas circuit breaker for a road reactor.

(Prior Art) In recent years, gas-insulated equipment is used for insulating media such as SF
By using an insulating gas such as ₆ gas, its size has been greatly reduced compared to conventional equipment. Now, it is possible to meet the specifications of rated voltage of 300kV and breaking current of 50kA with one arc-quenching chamber per phase. This is largely due to advances in gas flow analysis technology and electric field analysis technology in the arc-extinguishing chamber, which have been accumulated for many years.

In general, in a gas circuit breaker for a transmission line circuit, in order to suppress surge voltage during switching operation when switching a large current, a resistance contact in which a resistor is connected in series is connected in parallel to the main contact. A circuit breaker with a resistance is known. For example, a circuit breaker with a parallel resistor described in JP-A-58-115727,
A resistance contact, in which resistors are connected in series, is arranged above the main contact, and the operating rod of this resistance contact and the drive mechanism of the main contact are mechanically connected and linked through a link or the like. Further, Japanese Patent Application Laid-Open No. 59-96620 discloses a circuit breaker with a parallel resistor having a similar structure. As described in JP-A-59-96620, these circuit breakers with parallel resistors require about 25 ms from the start of the opening operation of the main contact to the start of the opening operation of the resistance contact in breaking. For this reason, a link mechanism was used to secure a delay time of about 25 ms for interlocking.

(Problems to be solved by the invention) By the way, the circuit breaker used for the general purpose as described above is a standard (JEC-23) of the Institute of Electrical Engineers of Japan
This is a standard circuit breaker based on 00), and this standard specifies current interruption, such as delayed small current interruption and short-circuit current interruption. However, since this standard does not cover circuit breakers for special purposes, when a standard circuit breaker based on the standard is used for special purposes,
Problems may occur, and it was necessary to give due consideration.

As a special application, as shown in Fig. 5 (A), 168kV ~ 3
There is a case where a gas circuit breaker BC is connected to a large capacity reactor L which is a shunt reactor connected to a 00kV class power transmission system or the like to disconnect the reactor. In this case, in general,
As shown in FIG. 5 (B), due to the cutoff phase between the voltage V and the current I, a sharp and high-cutoff surge SV of about 10 μm is generated after the current is cut off. This interruption surge SV causes arcing between the poles of the arc-extinguishing chamber, and if it is interrupted, a higher interruption surge occurs and eventually interruption becomes impossible. Therefore, it is required to cut off the current under extremely severe conditions.

Therefore, it is necessary to develop an arc-extinguishing chamber that has insulation recovery characteristics better than these breaking surges. From this point of view, the competition of insulation recovery between the arc contactor of the arc extinguishing chamber and the main contactor (insulation coordination) has hitherto been devised.

For example, it is known that a ceramic resistor is composed of a plurality of ceramics laminated bodies and has an excellent ability to suppress a reactor breaking surge. Therefore, it has been considered to suppress the breaking surge with this resistor. However, if the resistors are arranged with reference to the conventional circuit breaker with parallel resistance, the circuit breaker becomes large and connected by a delay mechanism such as a link, which is not necessary for suppressing sharp breaking surges, and a resistance contact is required. Therefore, there was a problem that it became complicated.

An object of the present invention is to provide a gas circuit breaker for a shunt reactor that can easily shut off the reactor by suppressing the reactor shutoff surge itself to some extent without increasing the size and complexity.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides an arc contactor for flowing an arc current in one arc extinguishing chamber and the arc contactor around the arc contactor. In a large-capacity puffer-type gas circuit breaker that has a main contactor through which an energizing current flows coaxially, a ceramic resistor is connected in series with the arc contactor and is arranged coaxially with the arc contactor. A gas circuit breaker for a shunt reactor is provided.

(Operation) In the present invention, since the ceramic resistor is connected to the arc contactor which has a time difference from the main contactor in the opening / closing operation, the breaking current flowing through the arc contactor flows through the ceramic resistor. With the use of the time difference between the opening and closing operations of the main contactor and the arc contactor, it is possible to effectively suppress a sharp breaking surge by the ceramic resistor. In addition, since the ceramic resistor is placed on the arc contact provided inside the main contact, it is possible to prevent the size from increasing, and the contact for the resistor is not necessary, and it occurs when the current is cut off with a simple structure. It is possible to suppress the interruption surge.

(Embodiment) An embodiment of the shunt reactor circuit breaker according to the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 1, a fixed side arc contactor 2 is fixed to the center of a fixed side main contactor 1 with an insulating stud 4 via a ceramic resistor 3.

The stationary sliding contact 5 is provided on the stationary main contact 1 surrounding the stationary arc contact 2. In addition, a buffer such as a spring may be inserted before or after the ceramic resistor 3 so that an impact load is not applied to the ceramic resistor 3.

Movable side arc contactor 6 facing stationary side arc contactor 2
Is provided at the tip of the puffer cylinder 7. Further, the movable side arc contactor 6 is surrounded by a nozzle 8 made of an insulating material, and the movable side main contactor is brought into contact with and separated from the fixed side sliding contactor 5 and the fixed side main contactor 1 on the outside of the nozzle 8. 9
Is provided. The puffer cylinder 7 is the operating rod 10
Is configured to slide on the outside of the puffer piston 11, and the movement of the puffer cylinder compresses the insulating gas in the puffer chamber 12 and blows it between the two contacts.

A case will be described in which the shunt reactor gas circuit breaker configured as described above is connected to a large capacity reactor to open and close the reactor circuit. When the gas circuit breaker in the open circuit state shown in FIGS. 1 and 2 is closed, the operating rod 10 is moved leftward in the figure by a drive mechanism (not shown). After the movable-side arc contactor 6 contacts the fixed-side arc contactor 2, the movable-side main contactor 9 contacts the stationary-side sliding contactor 5 and the stationary-side main contactor 1 to be inserted.

When opening the gas circuit breaker in the closed state, use the operating rod 10
Is moved to the right in the figure by a drive mechanism (not shown).
The movable side main contactor 9 separates from the fixed side main contactor 1 and the fixed side sliding contactor 5, and the circuit current moves to the movable arc contactor 6 and the fixed side arc contactor 2 side, and the current passes through the ceramic resistor 3. Flowing.

When the operating rod 10 moves further, the movable side arc contactor 6 separates from the fixed side arc contactor 2 and interrupts the current. This breaking current flows through the ceramic resistor 3, but the recently developed ceramic resistor not only has a high heat resistance temperature but also has a small size and a large capacity, so that it is shown in FIG. Effectively suppress the cut-off surge SV.

After a breaking current flows through the ceramic resistor 3, gas is blown from the puffer chamber 12 so that both contacts 2,
The arc between 6 will be interrupted.

Therefore, the recently developed ceramic resistor not only has a high heat-resistant temperature but also has a small size and a large capacity. Therefore, it is necessary to provide the fixed side arc contactor 2 near the arc as in the above-described embodiment. The ceramic resistor can effectively suppress the breaking surge. The ceramic resistor 3 also acts as a breaking resistance, but in the case of a resistor that is energized for a long time in order to suppress surge suppression when opening and closing a large current like a so-called conventional gas circuit breaker for transmission line circuits. Instead, it is a resistor for suppressing a steep reactor surge. Further, since the ceramic resistor 3 is arranged in the fixed side arc contactor 2 provided in the fixed side main contactor 1, the conventional arc extinguishing chamber can be used without increasing its size. Further, since it is not necessary to provide a resistor contact for opening and closing the ceramic resistor, it is possible to suppress the interruption surge that occurs when the current is interrupted with a simple structure.

Next, another embodiment will be described with reference to FIGS. 3 and 4. In another embodiment shown in the drawing, the ceramic resistor 3 is provided between the movable side arc contact 6 and the puffer cylinder 7 with the insulating stud 4 interposed therebetween. Also in the embodiment of FIG. 3, as shown in FIG. 4, since the ceramic resistor 3 enters in series with the movable side arc contact 6, it acts to suppress the breaking surge at the time of breaking the reactor. The same effect can be achieved.

[Advantage of the Invention] As described above, according to the present invention, a ceramic resistor that suppresses a surge voltage generated when the reactor current is cut off is connected in series as a part of the arc contactor and is coaxial with the arc contactor. By arranging and incorporating it, it is possible to provide a gas circuit breaker having a simple structure and capable of severe reactor shutoff without increasing the size of the arc extinguishing chamber.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an arc extinguishing chamber of a gas circuit breaker for a shunt reactor according to the present invention, FIG. 2 is an equivalent circuit diagram thereof, and FIGS. 3 and 4 are other embodiments of the present invention. 5A, 5B and 5C are a circuit diagram, a voltage-current characteristic diagram and a voltage-time characteristic diagram showing a mechanism of surge generation when the reactor is cut off. 1 ... Fixed side main contactor, 2 ... Fixed side arc contactor, 3
...... Ceramics resistor, 4 ...... Insulation stud, 6 ......
Movable side arc contactor, 7 ... Puffer cylinder, 8 ...
… Nozzle, 9… Movable main contactor, 10… Operation rod,
11 …… Puffer piston, 12 …… Puffer chamber.

Claims (1)

[Scope of utility model registration request] 1. A large capacity having an arc contactor through which an arc current flows in one arc extinguishing chamber, and a main contactor, which is arranged around the arc contactor and is coaxial with the arc contactor, through which an energizing current flows. A gas circuit breaker for a shunt reactor, characterized in that, in a puffer type gas circuit breaker, a ceramic resistor is connected in series with the arc contactor and is arranged coaxially with the arc contactor.