JPH0855548A - Puffer gas-blast circuit breaker - Google Patents

Abstract

PURPOSE:To provide a puffer gas-blast circuit breaker which has good breaking performance by reducing an electromagnetic force working on an arc, and improving the efficiency of exhausting hot gas. CONSTITUTION:A pair of a fixed electrode 2 and a movable electrode 3 which freely move into and out of contact with each other are arranged opposite to each other inside a closed container 1 filled with an arc-extinguishing gas. Conductors 5, 6 for taking currents in from the outside are connected respectively to the fixed electrode 2 and to the movable electrode 3. An arc between the opposite electrodes 2, 3 is extinguished by blowing the arc-extinguishing gas. The fixed electrode 2 comprises a cylindrical support member 19, a fixed arc contact 8 provided at the center of the support member 19, and a plurality of ribs 20 arranged radially so that the fixed arc contact 8 is supported to the support member. Of the plurality of ribs 20, those opposite to the conductor 5 for taking current into the gas-blast circuit breaker have electrical resistance the sum of which is smaller than the sum of the electrical resistance of the ribs located on the same side as the conductor 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a puffer type gas circuit breaker used in a substation or a switching station of a power system, and more particularly to a puffer type gas circuit breaker having an improved supporting structure for arc contacts on the fixed side. .

[0002]

2. Description of the Related Art With the increase in capacity of power transmission systems, the breaking capacity of circuit breakers used in substations and switchyards is increasing, and high reliability is required. In order to increase the reliability of the circuit breaker, it is important to reduce the number of parts and simplify the structure. Therefore, the number of circuit breakers has been reduced. Therefore, it is necessary to increase the breaking capacity per point of the breaker. In the conventional general puffer type gas circuit breaker, it is necessary to increase the gas pressure in the puffer chamber in order to improve the breaking performance.

For example, in the present 550 KV system, a circuit having a breaking power of 63 KA is practically used. This 550KV-6
The 3KA class circuit breaker consists of four points, but in order to improve the reliability of the circuit breaker, it is important to reduce the number of circuit breaks and the number of parts. 1 for this
It is necessary to improve the breaking capacity per breaking point and cut 550KV-63KA into 2 or 1 point.

In order to achieve such an improvement of the breaking capacity, what has been conventionally used in a transmission voltage system of 168 KV or more is a so-called puffer type gas circuit breaker which extinguishes arc by blowing gas. This has a simple structure of the breaker and has excellent insulation and arc extinguishing performance due to the enclosed SF6 gas. In addition, the entire substation equipment is S
In a closed gas-insulated switchgear that is insulated with F6 gas,
The insulating gas used can be used for insulation coordination between the circuit breaker and other equipment, and is efficient in terms of equipment arrangement, so it is particularly well used.

5 and 6 show the structure of a conventional puffer type gas circuit breaker. FIG. 5 shows the entire structure of the puffer type gas circuit breaker, in which the fixed electrode 2 and the movable electrode 3 are provided in the closed container 1 so as to face each other, and the fixed electrode 2 and the movable electrode 3 are provided outside. An insulating cylinder 4 is provided so as to surround it. The fixed electrode 2 and the movable electrode 3 are respectively connected with conductors 5 and 6 which are connected to an external device, and the movable electrode 3 is further connected with a drive mechanism 7 thereof. The movable electrode 3 is attached to the closed container 1 via a supporting insulating cylinder 10.

FIG. 6 shows details of the arc extinguishing chamber of such a puffer type gas circuit breaker. That is, the fixed electrode 2 is hollow, and the fixed arc contactor 8 is provided at the center thereof.
However, a cylindrical fixed current-carrying contactor 9 is arranged on the outside thereof. On the other hand, the movable electrode 3 connects the puffer piston 11 fixed to the closed container 1 side, the puffer cylinder 12 arranged outside the puffer piston 11, and the puffer cylinder 12 and the drive mechanism 7 to each other. Operation rod 13 inserted inside puffer piston 11
It has and. A movable arc contactor 14 that contacts the fixed arc contactor 8 and an insulating nozzle 15 that surrounds the movable arc contactor 14 are provided at the tip of the puffer cylinder 12. The fixed arc contactor 8 and the fixed energization contactor 9 are fixed to the closed container 1 by a support member 18.

In the conventional puffer type gas circuit breaker configured as described above, when the operating rod 13 is reciprocated by the drive mechanism 7, the movable electrode 3 opens and closes between the movable electrode 3 and the fixed electrode 2 facing the movable electrode 3, and the current flows. Shut off. Figure 6
Shows the state during the breaking operation, and in this state, the arc 16 is generated between the fixed arc contactor 8 and the movable arc contactor 14. Then, the puffer cylinder 12 moves in the left-right direction by the shut-off operation, and the puffer cylinder 1
The arc extinguishing gas is compressed in the puffer chamber 17 formed by 2 and the puffer piston 11. This compressed arc-extinguishing gas flow is controlled by the insulating nozzle 15 and the arc 1
It is blown to 6 and extinguishes it.

[0008]

In the puffer type gas circuit breaker as described above, the arc 16 is generated by the electromagnetic force generated by the interaction between the magnetic field generated by the current flowing through the conductors 5 and 6 and the arc 16. Since the arc extinguishing gas flow is also heated by the arc 16 at the same time as being bent in the direction of the arrow shown by 6, the heated hot gas flow also flows largely to the bent side. Therefore, even if the amount of hot gas is the same, the efficiency of exhausting hot gas when a large amount of hot gas gathers in one side becomes worse than that in the case of even flow. And
As more hot gas remains without being exhausted, the withstand voltage performance between the fixed arc contactor 8 and the movable arc contactor 14 deteriorates, which adversely affects the large current interruption performance.

The present invention has been made in order to solve the above-mentioned drawbacks of the prior art, and its purpose is to alleviate the electromagnetic force acting on the arc, improve the exhaust efficiency of hot gas, and have a good breaking performance. It is to provide a puffer type gas circuit breaker.

That is, a more specific object of the present invention is to
By weakening the magnetic field generated in the vicinity of the arc by the current flowing in the conductors 5 and 6 by the current flowing in the opposite direction to the current flowing in the conductor, the electromagnetic force due to the interaction between this magnetic field and the arc generated during the interruption operation is weakened. To reduce the bias of the arc.

Another object of the present invention is to flow a current in a direction opposite to the current flowing through the conductor to the rib supporting the fixed arc contact of the fixed electrode, whereby the arc is generated by the current flowing through the conductors 5 and 6. The purpose is to weaken the magnetic field generated in the vicinity.

[0012]

To achieve the above object, a puffer-type gas circuit breaker according to a first aspect of the present invention is provided with a pair of fixed electrodes that are movable in contact with and separated from each other in a closed container filled with arc-extinguishing gas. Electrodes are arranged so as to face each other, and conductors for taking in a current from the outside to the gas circuit breaker are connected to the fixed electrode and the movable electrode, respectively, in a direction perpendicular to the axial direction of the fixed electrode and the movable electrode. And a puffer cylinder are fixed to one end of an operating rod connected to a drive device, and the arc-extinguishing gas in the puffer cylinder is compressed by the puffer cylinder and the puffer piston sliding in the puffer cylinder. To a puffer-type gas circuit breaker for extinguishing by ejecting as a high-speed gas flow by an insulating nozzle fixed to the puffer cylinder and blowing the arc generated between the opposing electrodes to extinguish the arc. The fixed electrode is a cylindrical support member, a fixed arc contactor provided at the center of the support member, and a plurality of radial electrodes arranged to support the fixed arc contactor on the support member. Of the plurality of ribs, the sum of the electric resistances of the ribs on the side opposite to the conductor that takes in the current from the outside to the gas circuit breaker is equal to the electric resistance of the ribs on the same side as the conductor. It is characterized in that it is configured to be smaller than the total sum.

In the puffer-type gas circuit breaker according to a second aspect of the present invention, among the plurality of ribs, the total of the cross-sectional areas of the ribs on the side opposite to the conductor that takes in the current from the outside to the gas circuit breaker has the same side as the conductor. It is characterized in that it is configured so as to be larger than the total sum of the sectional areas of the ribs.

In the puffer type gas circuit breaker according to a third aspect of the present invention, among the plurality of ribs, the cross-sectional area per rib of the rib on the side opposite to the conductor for taking the current from the outside into the gas circuit breaker is the same as that of the conductor. It is configured to be larger than the cross-sectional area per rib on the same side, and the number of ribs on the side opposite to the conductor is the same as the number of ribs on the same side as the conductor. It is characterized by being configured.

In the puffer type gas circuit breaker according to a fourth aspect of the present invention, among the plurality of ribs, the number of ribs on the side opposite to the conductor that takes in current from the outside to the gas circuit breaker is the same as the conductor. The cross-sectional area of each rib on the side opposite to the conductor and the cross-sectional area of each rib on the same side of the conductor are substantially the same. It is characterized by being configured.

In the puffer type gas circuit breaker according to a fifth aspect of the present invention, among the plurality of ribs, the shape and the size of the rib on the side opposite to the conductor that takes in the current from the outside to the gas circuit breaker are the same as the conductor. The shape and size of a rib are substantially the same, and the rib on the side opposite to the conductor is made of a material having a conductivity higher than that of the material of the rib on the same side as the conductor. And

In the puffer type gas circuit breaker of claim 6, of the plurality of ribs, the material of the rib on the side opposite to the conductor that takes in the current from the outside to the gas circuit breaker is copper, and the same side as the conductor. The rib material is aluminium.

In the puffer-type gas circuit breaker according to a seventh aspect, of the fixed electrode and the movable electrode which are arranged to face each other so that they can come into contact with and separate from each other, the fixed electrode is driven in the direction opposite to the movable electrode in cooperation with the movable electrode. It is characterized by

[0019]

In the invention of claim 1, since the electric resistance of the rib in the direction opposite to the conductor is smaller than the electric resistance of the rib on the conductor side,
A larger amount of current flows on the rib side, which allows the magnetic field generated by the current flowing through the conductor to be canceled by the magnetic field generated by the current flowing in the opposite direction. As a result, the electromagnetic force acting on the arc is reduced, the distortion of the arc is reduced, the exhaust efficiency can be prevented from lowering due to the hot gas being biased in one direction, and the breaking performance can be improved.

In the second aspect of the present invention, the total cross-sectional area of the ribs located on the opposite side of the conductor is larger than the total cross-sectional area of the ribs on the conductor side, so that the electric resistance of the rib portion on the opposite side of the conductor is reduced. , More current flows to the rib side.

According to the third aspect of the present invention, since the cross-sectional area of the rib located on the side opposite to the conductor is larger than the cross-sectional area of the rib on the conductor side, even if the number of ribs on both sides is the same, the side opposite to the conductor is opposite. The electric resistance of the rib portion becomes smaller, and more current flows to this rib side.

According to the invention of claim 4, the number of ribs located on the side opposite to the conductor is larger than the number of ribs on the side of the conductor even if the cross-sectional areas of the individual ribs are substantially equal. Has a smaller electric resistance, and more current flows to the rib side.

According to the fifth aspect of the present invention, even if the cross-sectional areas of the individual ribs are substantially equal, the conductivity of the ribs located on the opposite side of the conductor is higher than the conductivity of the ribs on the conductor side, so that the opposite side of the conductor is formed. The electric resistance of the rib portion becomes smaller, and more current flows to this rib side.

According to the sixth aspect of the present invention, the electric conductivity of the copper rib located on the side opposite to the conductor is higher than the electric conductivity of the aluminum rib on the conductor side, so that the electric resistance of the rib portion on the side opposite to the conductor becomes small. , More current flows to the rib side.

In the invention of claim 7, since the fixed electrode is driven to the side opposite to the movable electrode at the time of interruption, the separation speed between both electrodes is high, and at the same time, more current flows to the side opposite to the conductor, so that the arc The magnetic field generated in the vicinity is weakened and excellent blocking performance is obtained.

[0026]

【Example】

(1) First Example A first example of the present invention will be specifically described with reference to FIGS. 1 and 2. FIG. 1 is a vertical sectional view showing details of the vicinity of an electrode of the puffer type gas circuit breaker of this embodiment, and FIG. 2 is a sectional view in the circumferential direction near the fixed electrode. In each figure, the same parts as those in the conventional technique shown in FIGS. 5 and 6 are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 1, in the first embodiment,
The fixed electrode 2 includes a cylindrical support member 19, a fixed arc contactor 8 provided at the center of the support member 19, and a radial arrangement for supporting the fixed arc contactor 8 on the support member 19. A plurality of ribs 20, 20a, 20b
It consists of and. Of the plurality of ribs, the sum of the electric resistances of the ribs 20b on the side opposite to the conductor 5 that takes in the current from the outside to the gas circuit breaker is greater than the sum of the electric resistances of the ribs 20a on the same side as the conductor 5. It is configured to be small. That is, in the first embodiment, as shown in FIG.
As shown in FIG. 6, among the ribs 20 supporting the fixed arc contactor 8 of the support member 19, as compared with the rib 20a on the same side as the conductor 5 with the fixed arc contactor 8 interposed therebetween, the rib 20b on the opposite side to the conductor 5 is provided. Has a large sectional area, the electric resistance of the rib 20b is smaller than that of the rib 20a.

In the first embodiment having such a structure, the current flowing from the outside into the gas circuit breaker flows through the conductor 5 to the fixed electrode 2. The current flowing into the fixed electrode 2 flows into the fixed arc contactor 8 via the support member 19 and the ribs 20, 20a, 20b. At this time, the amount of current flowing through the rib 20b is larger than that of the rib 20a.
The direction of the current flowing through the ribs of the supporting member 8 is the conductor 5
The magnetic field generated by the current flowing in the conductor 5 becomes opposite to the direction of the current flowing in the conductor 5, and the magnetic field generated by the current flowing in the rib of the support member 8 partially cancels. Therefore, as compared with the magnetic field generated by the current flowing through the conductor 5, the magnetic field generated near the arc is weakened, and the electromagnetic force is weakened accordingly.

As a result, when the fixed electrode 2 and the movable electrode 3 are separated due to the breaking operation, the arc 16 generated between the fixed arc contact 8 and the movable arc contact 14 is the rib 20 of the support member 19. Are all the same and have a cross-sectional area, the amount of bending by the magnetic field near the arc is smaller. In this way, the degree of bending of the arc is reduced, and when the arc-extinguishing gas compressed in the puffer chamber 17 is controlled by the insulating nozzle 15 and sprayed on the arc, the arc-extinguishing gas comes into contact with the arc. The degree to which the hot gas flows unevenly in the same direction as the arc is bent also decreases, and the hot gas flows more uniformly. As a result, the exhaust efficiency of the hot gas is improved, the withstand voltage performance between the fixed arc contact 8 and the movable arc contact 14 is also improved, and the large current interruption performance is improved.

(2) Second Embodiment A second embodiment of the present invention is shown in FIG. FIG. 3 is a circumferential sectional area near the fixed electrode in the puffer type gas circuit breaker of FIG. 1 as in FIG. In FIG. 3, the number of ribs 20 a on the conductor 5 side with respect to the fixed arc contactor 8 is different from the number of ribs 20 c, 20 d on the side opposite to the conductor 5.
In this case, the cross-sectional area of each rib is approximately the same, but the number of ribs is larger on the side opposite to the conductor,
Since the electric resistance of the rib is the reciprocal of the sum of cross-sectional areas, the electric resistance of the ribs 20c and 20d on the side opposite to the conductor 5 is smaller than the electric resistance of the rib 20a on the conductor 5 side. As a result, more current flows in the ribs 20c and 20d on the side opposite to the conductor than on the rib 20a on the conductor side, and the same effect as in the first embodiment can be obtained. Of course, the rib 20a may be omitted and the rib may be provided only on the side opposite to the conductor.

(3) Other Embodiments Another embodiment is shown in FIG. 4 is a circumferential sectional view near the fixed electrode in the puffer type gas circuit breaker of FIG. 1 similarly to FIG. In FIG. 4, the rib 20a on the conductor 5 side with respect to the fixed arc contactor 8 and the rib 20e on the side opposite to the conductor 5 are dimensionally symmetric, but the materials are different, and the conductivity of the material is the rib 20e. Is higher than the rib 20a. Examples of this include copper for the rib 20e and aluminum for the rib 20a. With this configuration, the electric resistance of the rib 20e on the side opposite to the conductor is smaller than the electric resistance of the rib on the side of the conductor, and as a result, the electric current flowing through the rib 20e on the side opposite to the conductor is smaller. Will flow more than the current flowing through the rib 20a on the conductor side. As a result, the same effect as that of each of the above embodiments can be obtained. Note that, at present, it is possible to join copper and aluminum by using brazing or the like, so that it is easy to realize a puffer type gas circuit breaker having ribs made of different materials.

In each of the above embodiments, the puffer type gas circuit breaker having the electrode structure in which the fixed electrode side is fixed to the closed container 1 has been described. Even if applied to a so-called dual motion type puffer type gas circuit breaker that moves the fixed electrode in the opposite direction to the movable electrode in order to increase the relative closing speed and opening speed, the same action and effect as above. Can be obtained.

[0033]

As described above, according to the present invention, the magnetic field generated in the vicinity of the arc due to the current flowing through the conductor is weakened by the current flowing through the rib in the opposite direction to the current flowing through the conductor, so that the magnetic field is interrupted during the interruption operation. The electromagnetic force due to the interaction with the arc generated can also be weakened. This allows
Since the bias of the arc is reduced and the hot gas heated by the arc flows in a more uniform state, the exhaust efficiency is improved and the interrupting performance can be improved, and the puffer type gas circuit breaker with higher interrupting performance. Can be provided.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a structure near an electrode in a first embodiment of a puffer type gas circuit breaker of the present invention.

FIG. 2 is a sectional view in the circumferential direction near the fixed electrode in the first embodiment.

FIG. 3 is a sectional view in the circumferential direction near a fixed electrode in the second embodiment.

FIG. 4 is a sectional view in the circumferential direction near a fixed electrode according to a third embodiment.

FIG. 5 is a vertical sectional view of a conventional puffer type gas circuit breaker.

6 is a vertical cross-sectional view showing a structure near an electrode of the puffer type gas circuit breaker of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Airtight container 2 ... Fixed electrode 3 ... Movable electrode 4 ... Insulating cylinder 5,6 ... Conductor 7 ... Driving mechanism 8 ... Fixed arc contactor 9 ... Fixed energizing contactor 10 ... Support insulating cylinder 11 ... Puffer piston 12 ... Puffer cylinder 13 ... Operation rod 14 ... Movable arc contactor 15 ... Insulation nozzle 16 ... Arc 17 ... Puffer chamber 18 ... Conventional supporting member 19 ... Supporting member 20 of the present invention ... Rib

Claims (7)

[Claims] 1. A pair of fixed electrodes and a movable electrode, which can be freely contacted and separated from each other, are arranged to face each other in an airtight container filled with an arc-extinguishing gas. Are connected to the fixed electrode and the movable electrode in a direction perpendicular to the axial direction of the fixed electrode and the movable electrode, respectively, and the movable electrode and the puffer cylinder are fixed to one end of an operation rod connected to a drive unit. The arc extinguishing gas in the puffer cylinder is compressed by the puffer piston that slides in the puffer cylinder, and the compressed gas is ejected as a high-speed gas flow by an insulating nozzle fixed to the puffer cylinder, and the opposing electrodes are compressed. In a puffer-type gas circuit breaker that extinguishes arcs by spraying on an arc generated between the fixed electrodes, the fixed electrode is provided in a cylindrical support member and at the center of the support member. It is composed of a constant arc contact and a plurality of ribs radially arranged to support the fixed arc contact on a support member. Among the plurality of ribs, an electric current is externally applied to the gas circuit breaker. The sum of the electric resistance of the ribs on the opposite side of the conductor to be taken in is
A puffer-type gas circuit breaker, wherein the puffer-type gas circuit breaker is configured so as to be smaller than a sum of electric resistances of ribs on the same side as the conductor. 2. The sum of the cross-sectional areas of the ribs on the side opposite to the conductor for taking the current into the gas circuit breaker from the outside of the plurality of ribs is more than the sum of the cross-sectional areas of the ribs on the same side as the conductor. The puffer-type gas circuit breaker according to claim 1, wherein the puffer-type gas circuit breaker is also configured to be large. 3. The cross-sectional area of one rib of the plurality of ribs on the side opposite to the conductor that takes in the current from the outside into the gas circuit breaker is one of the ribs on the same side as the conductor. And a number of ribs on the side opposite to the conductor are the same as the number of ribs on the same side as the conductor. The puffer type gas circuit breaker according to claim 2. 4. The number of ribs on the side opposite to the conductor for taking in current from the outside to the gas circuit breaker is larger than the number of ribs on the same side as the conductor among the plurality of ribs. And the cross-sectional area of each rib on the side opposite to the conductor is substantially the same as the cross-sectional area of each rib on the same side as the conductor. The puffer type gas circuit breaker according to claim 2. 5. The shape and size of the rib on the side opposite to the conductor for taking the current into the gas circuit breaker from the outside of the plurality of ribs is substantially the same as the shape and size of the rib on the same side as the conductor. And the rib on the side opposite to the conductor is made of a material having a conductivity higher than that of the material of the rib on the same side as the conductor. Gas circuit breaker. 6. The material of the rib on the opposite side of the conductor for taking the current into the gas circuit breaker from the outside of the plurality of ribs is copper, and the material of the rib on the same side as the conductor is aluminum. The puffer type gas circuit breaker according to claim 5, wherein 7. A fixed electrode and a movable electrode, which are arranged to face each other so that they can come into contact with and separate from each other, wherein the fixed electrode is driven in a direction opposite to the movable electrode in conjunction with the movable electrode. The puffer type gas circuit breaker according to 2, 3, 4, 5 or 6.