JPH0896668A - Gas-blast circuit-breaker - Google Patents

Abstract

PURPOSE: To provide a gas-blast circuit breaker by which an arc can be speedily, safely and reliably extinguished by preventing damage of an apparatus, and speedily translocating an electric current. CONSTITUTION: A current-carrying contactor 22 and an arc contactor 23 are arranged in parallel to each other, and this arc contactor 23 is arranged in series to a driving coil 8 in parallel to the current-carrying contactor 22. The current carrying contactor 22 is composed of a fixed current-carrying contactor 3 and a movable current-carrying contactor 4 which are arranged opposite to each other and have sliding contact parts. Among these sliding contact parts, an opening operation range surface of the movable current-carrying contactor 4 is composed of a resistance part 21 composed of a resistor or a coil. The arc contactor 23 is composed of a fixed arc contactor 6 and a movable arc contactor 7 which are arranged opposite to each other and have sliding contact parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas circuit breaker for turning on and off an electric current in a power transmission system, and in particular, to safely and surely extinguish an arc generated when the electric current is interrupted and turned on. The present invention relates to a gas circuit breaker that can be used.

[0002]

2. Description of the Related Art The demand for electric power is still increasing and the higher voltage of the power transmission system is advancing accordingly. In this high-voltage power transmission system, a gas circuit breaker having an excellent arc extinguishing capability is used because quick, safe and reliable interruption of an accident current is required. Many of such gas circuit breakers have a resistance breaker connected in parallel with the main breaker in order to mitigate a steep overvoltage generated immediately after turning on and off. When turning on the gas circuit breaker with this resistance, turn on the resistance breaking part first and apply current to the resistance.
The surge voltage is suppressed by turning on the main breaker after that. At the time of interruption, first, only the main interruption portion is opened to allow a current to flow through the resistor, and after that, the resistance interruption portion is opened to suppress the surge voltage.

Such a gas circuit breaker having the principle shown in FIG. 6 is disclosed in Japanese Utility Model Laid-Open No. 59-128136. FIG. 6 is a cross-sectional view of the electrode structure of the gas circuit breaker. In this gas circuit breaker, the fixed electrode portion and the movable electrode portion are provided with current-carrying contacts and arc contacts, respectively.

In FIG. 1, an insulating container 1 has an airtight structure, and an arc-extinguishing insulating gas such as SF ₆ gas is filled therein at a predetermined pressure. The fixed electrode portion is provided on the upper portion of the insulating container 1 having such heat resistance. That is, the cylindrical upper conductor 2 having the lower half portion as the fixed current-carrying contact 3 is attached to the upper portion of the insulating container 1. Inside the fixed energizing contact 3, a cylindrical fixed arc contact 6 and a drive coil 8 around the fixed arc contact 6 are arranged concentrically with the fixed energizing contact 3. One end of the drive coil 8 is connected in series around the fixed arc contact 6 and the other end is connected to the fixed energization contact 3 via the conductive piece 9. Further, the fixed energizing contact 3, the fixed arc contact 6, the drive coil 8 and the conductive piece 9 are integrated by an insulating resin filled in a mold portion 10 which is an internal space of the fixed energizing contact 3.

On the other hand, the movable energizing contactor 4 which constitutes the movable electrode portion is urged inward in the radial direction by the contact pressure spring 5, and the tubular movable arc contactor 7 is arranged inside the movable contactor 4 concentrically. To be done. Further, the fixed energizing contactor 3 and the movable energizing contactor 4 constituting the fixed electrode portion as described above, or the fixed arc contactor 6 and the movable arc contactor 7 constituting the movable electrode portion are respectively arranged in the movable electrode portion. It is configured to have a sliding contact portion that opens and closes by an operation.

In the above-described gas circuit breaker having such a structure, when the movable electrode portion moves during closing, the movable arc contactor 7 first contacts the lower end of the fixed arc contactor 6,
Next, the movable energizing contactor 4 is operated so as to come into contact with the fixed energizing contactor 3 from the outside. At this time, the current mainly flows through the path of the upper conductor 2, the fixed conducting contact 3, the movable conducting contact 4 and the lower conductor (not shown).

When the movable electrode portion moves in the direction away from the fixed electrode portion at the time of interruption, the movable energizing contactor 4 first separates from the fixed energizing contactor 3. At this time, the current is 2
The fixed energization contactor 3 → the conductive piece 9 → the drive coil 8 → the fixed arc contactor 6 → the movable arc contactor 7 → the commutation to the path of the lower conductor (not shown), and the drive coil 8 is excited. Next, the movable arc contactor 7 is operated so as to be separated from the fixed arc contactor 6, and at this time, an arc A is generated between both arc contactors. Since the arc A is linked with the magnetic flux generated by the drive coil 8, a rotational force is applied to the arc A and the arc A rotates at high speed. Therefore, the gas is relatively blown to the arc A, whereby the arc A is cooled and extinguished at the current zero point.

[0008]

The conventional gas circuit breaker as described above has the following problems. That is, due to the impedance of the drive coil 8 provided for applying a magnetic field to the arc A, when the fixed energizing contact 3 and the movable energizing contact 4 which are energizing contacts are opened, both energizing contacts There is a large potential difference between the children. At this time, the fixed energizing contact 3 and the movable energizing contact 4
A large discharge occurs on the surface of the bi-current contactor,
There is a risk that current cannot be commutated to the fixed arc contact 6, the movable arc contact 7 and the drive coil 8 side. In this case, the circuit breaker as a safety device may cause a catastrophic disaster. The present invention has been proposed in order to solve the above-mentioned problems of the prior art, and its first object is to alleviate a rapid potential difference generated between the fixed electrode portion and the movable electrode portion at the time of opening the electrode. Therefore, it is an object of the present invention to provide a gas circuit breaker capable of preventing damage to the sliding contact portion and the surface of the contactor, and swiftly diverting an electric current to quickly and safely perform a duty operation of extinguishing an arc.

Another object of the present invention is to make an equalization to connecting a current-carrying contact in series with a resistor in the process of opening and disconnecting, so that the commutation of the current to the arc contact side is smoothly performed. This is to prevent the surface of the current-carrying contact from being damaged as in the conventional case.

Another object of the present invention is to gradually reduce the potential difference generated between both electrode portions in the process of opening and separating.

[0011]

In order to achieve the above object, a gas circuit breaker according to claim 1 has a pair of fixed electrode portion and movable electrode portion in a container filled with an insulating gas having an arc extinguishing property. Are arranged to face each other, and the fixed electrode portion and the movable electrode portion have fixed side and movable side sliding contact portions that are opened and closed by the operation of the movable electrode portion. In a gas circuit breaker equipped with an operating mechanism that opens and closes the sliding contact part, both sliding contact parts are made of good conductor, and the contact opening range of the fixed side sliding contact part is made of a resistor. It is characterized by being.

A gas circuit breaker according to a second aspect is the gas circuit breaker according to the first aspect, wherein the fixed electrode portion and the movable electrode portion have current-carrying contacts and arc contacts, and the resistor is provided on the current-carrying contactor. It is characterized by being.

A gas circuit breaker according to a third aspect is the gas circuit breaker according to the first or second aspect, wherein the resistance value of the resistor increases stepwise in the opening operation direction of the movable electrode portion. Is characterized by.

According to a fourth aspect of the present invention, in a gas circuit breaker, a pair of a fixed electrode portion and a movable electrode portion are arranged to face each other in a container filled with an arc extinguishing insulating gas, and the fixed electrode portion and the movable electrode portion are disposed. Has a fixed-side and movable-side sliding contact part that opens and closes according to the operation of the movable electrode part, and is equipped with an operating mechanism that drives the movable electrode part to open and close the fixed-side and movable-side sliding contact parts. In the gas circuit breaker, both sliding contact parts are made of a good conductor, and the opening contact operating range surface of the fixed side sliding contact part is made of a coil of at least one turn.

A gas circuit breaker according to a fifth aspect is the gas circuit breaker according to the fourth aspect, in which the fixed electrode portion and the movable electrode portion have current-carrying contacts and arc contactors, and the coil is provided in the current-carrying contactors. It is characterized by

[0016]

In the gas circuit breaker according to claim 1 having the above-mentioned structure, when the switch is turned on, the fixed electrode portion and the movable electrode portion are in contact with each other and are in an energized state. Flow to the route. When the contact is opened, the movable electrode part moves in the opening direction along the sliding contact part of the fixed electrode part. At this time, the contact opening operation range surface of the sliding contact portion of the fixed electrode portion is formed of a resistor. Therefore, the opening operation by the movable electrode part is a good conductor →
It opens after passing through the resistor. By thus passing the movable electrode portion through the resistor, it is equivalent to connecting reactance in series between the movable electrode portion and the fixed electrode portion in the process of opening and separating.

Further, in the gas circuit breaker according to the second aspect, the sliding contact portion of the movable energizing contact is a good conductor in the opening process.
Open through the resistor. Therefore, the reactance is the same as the reactance is connected in series between the fixed energizing contact and the movable energizing contact.

In the gas circuit breaker of the third aspect, since the resistance value of the resistor increases stepwise in the opening operation direction of the movable electrode portion, the sliding contact portion of the movable energizing contactor in the opening process. The resistivity of each layer in contact with will also increase stepwise. As a result, the current path from the fixed energizing contact to the movable energizing contact is not suddenly cut off during the opening process, and the potential difference generated between the stationary energizing contact and the moving energizing contact during the opening process is mitigated. To be done.

In the gas circuit breaker of the fourth aspect, the movable electrode portion moves in the opening direction of the sliding contact portion of the fixed electrode portion when the electrode is opened. Since the contact opening operation range surface of the sliding contact portion of the fixed electrode portion is composed of a coil, the movable electrode portion is opened after sliding the contact from the good conductor to the coil. by this,
Reactance is equivalent to being connected to the current contact 22.

In the gas circuit breaker of the fifth aspect, in the opening process, the sliding contact portion of the movable energizing contactor is opened via the good conductor → the coil. Therefore, the reactance is equivalent to connecting the fixed energizing contact and the movable energizing contact in series.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments corresponding to claims 1 to 5 according to the present invention will be specifically described below with reference to the accompanying drawings. 1 to 6, the same parts are designated by the same reference numerals.

(1) First Embodiment A first embodiment shown in FIG. 1 is a sectional view showing an electrode structure in a closed state of a gas circuit breaker according to claim 2 of the present invention, and FIG. FIG. 3 is a sectional view showing the electrode structure in the middle of operation, and FIG. 3 is a sectional view showing the electrode structure in the separated state.

In the figure, a current-carrying contact 22 and an arc contact 23
Are arranged in parallel in a coaxial manner, and the arc contact 23 is arranged in series with the drive coil 8 which is parallel to the energizing contact 22. The current-carrying contactors 22 are fixed and the movable current-carrying contactors 4, which are arranged facing each other and have a sliding contact portion.
Composed of. Of the sliding contact portion, the resistance portion 21 which is the opening operation range surface of the movable energization contactor 4 is composed of a resistor. The arc contactor 23 is composed of a fixed arc contactor 6 and a movable arc contactor 7 which are arranged opposite to each other and have a sliding contact portion. In addition, the separating operation of the fixed energizing contactor 3 and the movable energizing contactor 4 is divided into the first term and the second term, and the first term of the opening operation is simply referred to as an opening state.
The latter part of the opening operation is called the opening state. In this open state, the fixed energizing contact 3 and the movable energizing contact 4 are separated, but the fixed arc contact 6 and the moving arc contact 7 have contact surfaces. Then, in the separated state, the fixed arc contact 6
The movable arc contactor is also arranged so as to be completely separated.

In the gas circuit breaker of the present embodiment having the above-described structure, the fixed current-carrying contact 3, the movable current-carrying contact 4, and the fixed arc contactor, as shown in FIG. 6 and the movable arc contactor 7 are in contact with each other and are in an energized state. At this time, the current flows through the energizing contactor 22 along the path from the fixed energizing contactor 3 to the movable energizing contactor 4.

FIG. 2 shows an intermediate state of the opening operation,
The movable energizing contactor 4 is moving in the opening direction and is in sliding contact with the resistance portion 21 of the stationary energizing contactor 3. After this,
In the open state, the fixed energizing contact 3 and the movable energizing contact 4 are separated. At this time, since the fixed arc contact 6 and the movable arc contact 7 have a sliding contact portion, the current is commutated from the energizing contact 22 side to the arc contact 23 side. At this time, the current flows through the path of the drive coil 8 → the fixed arc contact 6 → the movable arc contact 7. Further, in the separated state shown in FIG. 3, the fixed arc contactor 6 and the movable arc contactor 7 are completely separated, but an arc is generated between the fixed arc contactor 6 and the movable arc contactor 7 to bridge the bridge. To be done.

In the gas circuit breaker of this embodiment as described above,
From the opening of the fixed energizing contactor 3 and the movable energizing contactor 4 in the separation process, the movable energizing contactor 4 slides from the good conductor of the fixed energizing contactor 3 to the resistance portion 21 to open the contact. This is equivalent to connecting the current-carrying contact 22 in series with the resistor in the separation process. Therefore, the potential difference generated between the fixed energizing contact 3 and the movable energizing contact 4 is alleviated, and the current is smoothly commutated from the energizing contact 22 side to the arc contact 23 side. The surface of the contactor is not damaged. In addition, the function of the drive coil 8 connected to the fixed arc contactor 6 will be sufficiently exerted. As described above, in the gas circuit breaker of the present embodiment, the gas circuit breaker having a good breaking performance capable of quickly and safely performing the duty operation of extinguishing the arc by preventing damage to the equipment and swiftly passing the current. Can be provided.

(2) Second Embodiment A second embodiment shown in FIG. 4 is a sectional view showing an electrode structure in the middle of the opening operation of the gas circuit breaker according to claim 3 of the present invention. Note that this embodiment has the same basic configuration as that of the first embodiment.

In the figure, the resistance value of the resistance portion 21 is constructed so as to increase stepwise in the opening direction of the movable energizing contact 4. In the present embodiment, this is configured in three stages, and the resistivity of each layer is set to r1, r2, r3 in the order in which the movable energizing contactor 4 contacts. This resistivity relationship is r1 <
It is adjusted so that r2 <r3.

In the gas circuit breaker of the present embodiment having the above-mentioned structure, the movable energizing contact 4 is fixed to the fixed energizing contact 3 in the process of opening and disconnecting the fixed energizing contact 3 and the moving energizing contact 4. Good conductor → r1 of resistor 21 → r of resistor 21
2 → Slides to r3 of the resistance portion 21 and passes.

In the gas circuit breaker of this embodiment as described above,
In the process of opening and separating the fixed energizing contactor 3 and the movable energizing contactor 4, the resistivity of each layer in contact with the moving energizing contactor 4 increases stepwise as r1, r2 and r3. As a result, the current path from the fixed current-carrying contactor 3 to the movable current-carrying contactor 4 is not suddenly cut off, and the potential difference generated between the fixed current-carrying contactor 3 and the movable current-carrying contactor 4 changes stepwise. As a result, the commutation of the electric current to the arc contactor 23 side is performed more smoothly, and the surface of the current-carrying contactor is not damaged unlike the conventional case. Therefore, in the gas circuit breaker of this embodiment,
It is possible to provide a gas circuit breaker with good breaking performance that is less likely to damage the equipment.

(3) Third Embodiment A third embodiment shown in FIG. 5 is a cross-sectional view showing an electrode structure in the middle of the opening operation of a gas circuit breaker according to claim 5 of the present invention.

This embodiment is different from the first embodiment in the structure of the sliding contact portions of the fixed current-carrying contactor 3 and the movable current-carrying contactor 4, but the other basic structure is the same as that of the first embodiment. is there.

In the figure, of the sliding contact portions of the fixed current-carrying contactor 3 and the movable current-carrying contactor 4, a contactor coil 31 is embedded in the contact opening range of the movable current-carrying contactor 4. Therefore, in the gas circuit breaker of this embodiment, the movable energizing contact 4 slides on the surface of the contactor coil 31 in the opening direction when the contact is opened.

In the gas circuit breaker of this embodiment as described above,
The movable energizing contact 4 slides from the good conductor to the contact coil 31 in the process of opening and closing the fixed energizing contact 3 and the moving energizing contact 4. As a result, the reactance becomes equal to the fact that the reactance is connected to the energizing contact 22. Therefore, this reactance component increases and the arc contact 23
The commutation of the electric current to the side is performed more smoothly.

[0035]

As described above, according to the present invention, the sliding contact portion is made of a good conductor, and the sliding surface in the opening operation range of the movable electrode portion of the sliding contact portion in the fixed electrode portion is a resistor or at least By constructing the coil with one or more turns, it is possible to alleviate the overvoltage that occurs when the contacts are opened, prevent damage to the device, and quickly commutate the current. As a result, it is possible to provide a gas circuit breaker with a good breaking performance that can perform the duty operation of extinguishing arc quickly and safely.

[Brief description of drawings]

FIG. 1 is a sectional view showing an electrode structure in a closed state of a gas circuit breaker according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the electrode structure in the middle of the opening operation of the gas circuit breaker of the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the electrode structure of the gas circuit breaker of the first embodiment of the present invention in an open state.

FIG. 4 is a cross-sectional view showing the electrode structure of the gas circuit breaker of the second embodiment of the present invention during the opening operation.

FIG. 5 is a cross-sectional view showing an electrode structure in the middle of the opening operation of the gas circuit breaker of the third embodiment of the present invention.

FIG. 6 is a sectional view of an electrode structure in a conventional gas circuit breaker.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulation container 2 ... Upper conductor 3 ... Fixed energizing contactor 4 ... Movable energizing contactor 5 ... Contact spring 6 ... Fixed arc contactor 7 ... Movable arc contactor 8 ... Driving coil 9 ... Conductive piece 10 ... Mold part 21 ... resistance part 22 ... energizing contact 23 ... arc contact 31 ... contact coil A ... arc

Claims (5)

[Claims] 1. A pair of fixed electrode part and movable electrode part are arranged facing each other in a container filled with an arc-extinguishing insulating gas,
The fixed electrode portion and the movable electrode portion have fixed side and movable side sliding contact portions that are opened and closed by the operation of the movable electrode portion, and the movable electrode portion is driven to slide between the fixed side and the movable side. In a gas circuit breaker equipped with an operating mechanism for opening and closing a contact part, both of the sliding contact parts are made of a good conductor, and an opening operation range surface of the fixed side sliding contact part is made of a resistor. A gas circuit breaker characterized by being. 2. The gas according to claim 1, wherein the fixed electrode portion and the movable electrode portion have an energizing contact and an arc contact, and the resistor is provided on the energizing contact. Circuit breaker. 3. The gas circuit breaker according to claim 1, wherein the resistance value of the resistor increases stepwise in the opening operation direction of the movable electrode portion. 4. A pair of fixed electrode section and movable electrode section are arranged to face each other in a container filled with arc-extinguishing gas, and the fixed electrode section and the movable electrode section operate as the movable electrode section. It has a fixed side and a movable side sliding contact part that open and close by
In a gas circuit breaker equipped with an operating mechanism for driving the movable electrode portion to open and close the sliding contact portions on the fixed side and the movable side, both sliding contact portions are made of good conductors, and A gas circuit breaker characterized in that a contact opening operating range surface of the sliding contact portion is constituted by a coil having at least one turn. 5. The gas shutoff according to claim 4, wherein the fixed electrode portion and the movable electrode portion have an energizing contact and an arc contact, and the coil is provided on the energizing contact. vessel.