JP6435227B2 - Gas circuit breaker - Google Patents

Description

  The present invention relates to a puffer-type gas circuit breaker, and more particularly to a circuit breaker using a mechanical compression action, a heating pressure raising action by arc heat, or both.

  The gas circuit breaker is for interrupting an accident current caused by a short circuit between phases or a ground fault in an electric power system. Conventionally, puffer-type gas circuit breakers have been widely used. This puffer-type gas circuit breaker generates a high-pressure gas flow by mechanically compressing the arc extinguishing gas using a movable puffer cylinder directly connected to the movable arc contact, and between the movable arc contact and the fixed arc contact. The current is interrupted by spraying on the arc generated in Since the shut-off performance depends on the pressure increase in the puffer chamber, in addition to the conventional pressure increase due to mechanical compression, a heat puffer combined gas circuit breaker that actively uses the thermal energy of the arc to increase the pressure is also widely used. ing. The heat puffer combined gas circuit breaker uses the thermal energy of the arc to create the arc extinguishing gas blowing pressure, compared to the conventional mechanical compression method of operating energy required for the breaking operation. Can be reduced.

  In addition, in order to improve the shutoff performance, the shape of the space formed by the insulating nozzle and the fixed arc contactor has been studied in detail for both the puffer type gas circuit breaker and the heat puffer combined type gas circuit breaker. Yes. The space is a flow path of an arc generated between the movable arc contact and the fixed arc contact, and an arc extinguishing gas blown against the arc. When the fault current is interrupted, the insulating nozzle and the movable arc contact are operated by the opening operation, and the shape of the flow path between the fixed arc contact changes every moment according to the opening operation.

  Furthermore, in the interruption of the fault current, it is necessary to consider the time from the so-called opening time to the breaking time when the movable arc contact and the fixed arc contact are dissociated and the arc is generated, so-called arc time. A circuit breaker such as a gas circuit breaker breaks over the shortest arc time that the gas circuit breaker can break, the so-called shortest arc time, and the shortest arc time plus an arc current frequency of 0.5 cycles, the so-called longest arc time. There is a need. In the vicinity of the shortest arc time and the longest arc time, the relative positional relationship between the movable part of the interrupting part including the insulating nozzle and the movable arc contact and the fixed arc contact differs with the opening operation, and the flow path shape and The channel area is also different.

  Therefore, it is necessary to consider the formation of the spray pressure and the change in the shape of the flow path in order to improve the blocking performance.

  By the way, Patent Document 1 discloses a puffer type gas intended to improve arc extinguishing performance by effectively using high-pressure gas generated by a puffer chamber by suppressing gas blowout at the beginning of the shut-off operation period. A circuit breaker is disclosed.

  According to Patent Document 1, a nozzle for concentrating high-pressure gas flowing out from a puffer chamber to an arc is connected via a spring so that the relative position with respect to the movable-side arc contact portion is variable, and the gas pressure is a predetermined value. When the pressure is exceeded, the spring is contracted by the force applied to the nozzle, the nozzle and the arc contact part are separated to form a gas flow path, and the high-pressure gas generated by the puffer chamber by blowing out the high-pressure gas is efficient in extinguishing the arc There is a description that it is often used.

  However, if the pressure in the puffer chamber and the pressure in the arc space are balanced, the nozzle operation may not be stable, and the flow passage area in the nozzle may fluctuate and the performance may become unstable. This becomes more influential when the pressure in the arc space fluctuates following the breaking current phase, such as when the arc time becomes long.

JP-A-5-135669

  The above background art has the following problems. That is, the interruption performance is improved at a long arc time. In the longest arc time, the arc time is long, the arc energy generated between the movable arc contact and the fixed arc contact is larger than the shortest arc time, and the thermal load between both contacts is large.

  Furthermore, in addition to the state where the thermal load between the arc contacts is large as described above, the flow area formed by the insulating nozzle and the fixed arc contact is larger than the state of the shortest arc time, and the blowing gas flow rate There is a problem that the flow velocity and the like decrease compared to the shortest arc time.

  In particular, in a gas circuit breaker combined with a heat puffer, arc pressure is used to form a blowing pressure, so that if the flow path area formed by an insulating nozzle and a fixed arc contact is large, the arc heat is generated in a heat puffer chamber. In addition to flowing into the nozzle, it flows out in the downstream direction of the insulating nozzle, which makes it difficult to form the spray pressure.

  An object of the present invention is to obtain a stable interruption performance over a specified arc time.

  In order to solve the above-described problems, a gas circuit breaker according to the present invention includes a pair of electrodes that are opposed to each other in a container filled with an arc extinguishing gas, and an insulating nozzle ( 4), the insulating nozzle (4) has an insulating nozzle body (14) and an insulating nozzle tip (15), and the inner peripheral side or outer peripheral side of the insulating nozzle tip (15). The insulating nozzle body (14) is configured to slide, and while sliding with the outer edge of the insulating nozzle tip (15), the insulating nozzle tip (15) is locked when the pair of electrodes are opened. The electrode supporting conductor (43) on the side facing the side where the insulating nozzle (4) is provided has a locking member (41) to be insulated. The insulating nozzle tip (15) and the electrode supporting conductor (43) are spring-loaded. It is connected.

  According to the puffer-type gas circuit breaker of the present invention, the flow path shape and flow path area formed from the fixed arc contact and the nozzle tip can be kept constant from the middle of the opening operation. It is possible to make the flow path shape and the flow path area constant at the shortest arc time and the longest arc time, and the interruption performance can be improved.

It is a schematic sectional drawing which shows a puffer type gas circuit breaker. It is a schematic sectional drawing which shows the closing state in the interruption | blocking part of the puffer type gas circuit breaker which is one Example of this invention. It is a perspective view of the insulation nozzle and nozzle stopper in the interruption | blocking part of the puffer type gas circuit breaker which is the 1st Example of this invention. It is a schematic sectional drawing which shows the middle of the opening operation in the interruption | blocking part of the puffer type gas circuit breaker which is the 1st Example of this invention. It is a schematic sectional drawing which shows the opening state in the interruption | blocking part of the puffer type gas circuit breaker which is the 1st Example of this invention. It is a perspective view of the nozzle stopper in the interruption | blocking part of the puffer type gas circuit breaker which is the 1st Example of this invention. It is a perspective view which concerns on the modification of a nozzle stopper. It is a schematic sectional drawing which shows the middle of the opening operation | movement in the interruption | blocking part of the puffer type gas circuit breaker which is the 2nd Example of this invention. It is a perspective view of the nozzle stopper in the interruption | blocking part of the puffer type gas circuit breaker which is the 2nd Example of this invention. It is a schematic sectional drawing which shows the opening operation middle in the interruption | blocking part of the puffer type gas circuit breaker which is the 3rd Example of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to the following embodiment, It is also possible to implement suitably changing the shape and structure of each part in the range which does not deviate from the meaning of this invention.

  FIG. 1 is a sectional view of a puffer type gas circuit breaker to which the present invention is applied. The puffer-type gas circuit breaker according to the present invention includes an arc-extinguishing insulating gas filling container 2 and an operation mechanism 1, and a movable main contact 5 and a fixed main contact 6 that can be brought into and out of contact with the inside of the filling container 2. The movable arc contact 11 and the fixed arc contact 12 that can be brought into and out of contact with each other are arranged.

  These main contacts and arc contacts are contacted and separated by the driving force of the operating mechanism 1 via the insulating operating rod 3. In the puffer-type gas circuit breaker of the present invention, the insulating nozzle 4 is disposed so as to surround the movable arc contact 11 and the fixed arc contact 12 described above. Further, the arc space portion is formed by the heat of the arc formed between the movable arc contact 11 and the fixed arc contact 12 in the insulating nozzle 4 when the movable arc contact 11 and the fixed arc contact 12 are separated. The thermal puffer chamber 22 into which the insulating gas whose pressure has been increased is introduced, and the mechanical puffer chamber 32 which is provided in series with the thermal puffer chamber 22 and increases the pressure of the insulating gas by mechanical compression.

  In the embodiment described below, the fixed arc contact 12 and the fixed main contact 6 are described as being fixed for convenience, but even in the case of a so-called bidirectional drive system in which these operate, To establish.

  Hereinafter, the gas circuit breaker of Example 1 to which this invention is applied is demonstrated using drawing.

  As shown in FIG. 1, a movable main contact 5 and a fixed main contact 6 that can be contacted / separated, and a movable arc contact 11 that can be contacted / separated are fixed in an arc-filling insulating gas container 2. An arc contact 12 is arranged.

  The movable arc contact 11 and the fixed arc contact 12 are surrounded by an insulating nozzle 4, and the insulating nozzle 4 is fixed to the tip of the cylinder 17. The outer surface of the tip of the cylinder 17 is the movable main contact 5, and the movable arc contact 11 is fixed to the tip of the hollow rod 18 disposed in the cylinder 17.

  The fixed arc contact 12 is supported by an arc contact support conductor 43. As shown in FIG. 3, the electrode support conductor 43 has a rod shape and does not close all the space on the right side of the paper surface from the insulating nozzle 4.

  The hollow rod 18 is mechanically connected to the operating mechanism 1 via the insulating rod 3. When the operating mechanism 1 operates, the insulating rod 3, the hollow rod 18, the cylinder 17, the movable main contact 5, and the movable arc contact. The child 11 and the insulating nozzle 4 operate in the left-right direction on the paper surface in conjunction with the operation mechanism 1.

  As shown in FIG. 2, the insulating nozzle 4 is configured to be separable into an insulating nozzle body 14 and an insulating nozzle tip 15, and the insulating nozzle body 14 slides along the inner diameter of the insulating nozzle tip 15. Is possible. Here, the insulating nozzle body 14, the insulating nozzle tip 15, and the insulating nozzle outer edge 16 are all referred to as an insulating nozzle 4. The protruding portion on the outer peripheral side of the insulating nozzle tip 15 is an insulating nozzle outer edge portion 16, and corresponds to the outer peripheral end of the insulating nozzle tip 15 in this embodiment.

  A nozzle stopper 41 is fixed to the electrode support conductor 43 with a bolt or the like through an opening 44 provided in the outer periphery 16 of the insulating nozzle on the outer peripheral side of the insulating nozzle tip 15. (See FIG. 3).

  In the present embodiment, the coil spring 42 is disposed on the outer peripheral side of the nozzle stopper 41. When the fault current is interrupted, the hot gas due to the arc diffuses to the inner peripheral side of the stationary main contact 6, so that the nozzle stopper 41 protects the coil spring 42 from being exposed to the high temperature gas, and the coil spring 42 is deteriorated or damaged. Can be prevented.

  Further, the nozzle stopper 41 in this embodiment has a flat inner peripheral surface as shown in FIG. At this time, the shape of the opening 44 (see FIG. 3) provided in the insulating nozzle outer edge portion 16 may be matched with the shape of the nozzle stopper 41.

  The end portion of the nozzle stopper 41 on the insulating nozzle outer edge portion 16 side has a shape in which the end portion is bent and the bent inner surface forms a nozzle stopper facing surface 45 that faces the surface of the insulating nozzle outer edge portion 16. . The bending direction of the end of the nozzle stopper 41 does not matter. In FIG. 2, the end portion is bent toward the inner diameter direction, but may be bent toward the outer diameter direction, for example. Furthermore, a shape in which the end portion is expanded in both the inner diameter direction and the outer diameter direction is also possible.

  As for the material of the nozzle stopper 41, the nozzle stopper 41 is fixed to the electrode support conductor 43 to which a transient high voltage generated when the system voltage and the fault current are interrupted is applied. In consideration of the insulation coordination between the contacts 6, it is desirable to use an insulating material. However, if appropriate measures are taken for insulation coordination, the material is not limited to the insulating material.

  Next, the operation of the nozzle stopper 41, the coil spring 42, the insulating nozzle 4 and the like in the opening operation process will be described with reference to FIGS. 2, 3, 4, and 5. FIG.

  As shown in FIG. 2, the coil spring 42 is in a compressed state by the insulating nozzle 4 and the electrode support conductor 43 in the closed state. The coil spring 42 serves as a driving force for the nozzle tip 15 in the opening operation.

  FIG. 4 shows a schematic cross-sectional view of the blocking portion at the stop position of the nozzle tip 15 during the opening operation. The nozzle tip 15 is locked by the nozzle stopper 41, and as shown in FIG. 5, even if the opening operation is completed and the nozzle body 14 is moved to the opening position, the position of the nozzle tip 15 is reached. Is retained.

  As shown in FIGS. 4 and 5, the flow path shape and the minimum flow path area formed by the fixed arc contact 12 and the inner periphery of the nozzle tip 15 are maintained. Thereby, it becomes possible to make the flow path shape and flow path area constant at the shortest arc time and the longest arc time, and to improve the interruption performance.

  It should be noted that the sliding portion of the nozzle body 14 and the nozzle tip 15 has such a length that the sliding portion of the nozzle body 14 and the nozzle tip 15 does not drop even at the opening position.

  FIG. 7 shows a modification of the nozzle stopper 41 applied to this embodiment. In this embodiment, the inner peripheral surface 46 of the nozzle stopper 41 has a curved surface. Thereby, compared with the structure shown in FIG. 6, the nozzle stopper 41 can be expanded in the circumferential direction. Thereby, it is possible to reduce the amount of high-temperature gas diffusing between the movable main contact 5 and the fixed main contact 6, and the possibility of dielectric breakdown due to the high-temperature gas between the main contacts can be reduced.

  Next, Embodiment 2 of the present invention will be described with reference to FIG. Since details of the present embodiment excluding the nozzle stopper 41 are the same as those of the first embodiment, detailed description thereof is omitted. FIG. 8 shows a cross-sectional view of the gas circuit breaker of the third embodiment. In this embodiment, an elastic body such as a coil spring 42 is disposed on the inner peripheral side of the nozzle stopper 41 and is fixed by being embedded in a countersink hole provided in the insulating nozzle tip 15 or the like.

  In the first embodiment, the high-temperature gas flows through the periphery of the nozzle stopper 41. However, in this embodiment, the nozzle stopper 41 can be formed in a cylindrical shape as shown in FIG. It is possible to prevent diffusion between the main contact 5 and the fixed main contact 6, and it is possible to prevent dielectric breakdown due to high-temperature gas between the main contacts.

  Further, since the portion protruding to the outer periphery such as the outer peripheral edge portion 16 of the insulating nozzle can be made smaller than the configuration of the first embodiment, it is possible to reduce the weight of the tip end of the insulating nozzle tip portion 15 for the opening operation. It is possible to reduce the weight of the part which moves together.

  Example 3 is shown in FIG. The difference between the third embodiment and the first embodiment is that the sliding surface of the movable nozzle is the outer peripheral surface of the insulating nozzle tip 15 and the inner peripheral surface of the insulating nozzle main body 14. Even with this configuration, the same effect as the above example can be achieved. Furthermore, it is possible to reduce the risk of nozzle deterioration by keeping the thin portion of the insulating nozzle main body 14 away from the arc generated at the time of interruption.

  The puffer type gas circuit breaker of the present invention is not limited to the structure shown in the above-described embodiments, and can be implemented by appropriately changing the shape and configuration of each part without departing from the spirit of the present invention. .

  DESCRIPTION OF SYMBOLS 1 ... Operation mechanism, 2 ... Filling container, 3 ... Operation rod, 4 ... Insulation nozzle, 5 ... Movable main contact, 6 ... Fixed main contact, 11 ... Movable arc contact, 12 ... fixed arc contact, 13 ... mover cover, 14 ... insulated nozzle body, 15 ... insulated nozzle tip, 16 ... insulated nozzle outer edge, 17 ... Cylinder, 18 ... Insulating rod, 19 ... Partition, 20 ... Communication part, 21 ... Flow path, 22 ... Heat puffer chamber, 23 ... Movable valve, 31 ... -Arc space, 32 ... mechanical puffer chamber, 41 ... nozzle stopper, 42 ... coil spring, 43 ... electrode support conductor, 44 ... opening, 45 ... nozzle stopper facing surface, 46 ... Inner peripheral surface of nozzle stopper

Claims (6)

In a gas circuit breaker having a pair of electrodes facing and separating from each other in a container filled with arc-extinguishing gas, and an insulating nozzle provided on one of the electrodes,
The insulating nozzle has an insulating nozzle body and an insulating nozzle tip;
The inner peripheral side or outer peripheral side of the insulating nozzle tip and the insulating nozzle main body are configured to slide,
An electrode support on the side opposite to the side where the insulating nozzle is provided is provided with a locking member that slides on the outer edge of the insulating nozzle tip and engages with the insulating nozzle tip when the pair of electrodes are opened. Provided in the conductor,
The gas circuit breaker, wherein the insulating nozzle tip and the electrode support conductor are connected by a spring. In claim 1,
A gas circuit breaker characterized in that an inner peripheral surface of the locking member is a flat surface. In claim 1,
A gas circuit breaker characterized in that an inner peripheral surface of the locking member is a curved surface. In claim 1,
The gas circuit breaker, wherein the spring is disposed on an outer peripheral side of the locking member. In claim 1,
The gas circuit breaker, wherein the spring is disposed on an inner peripheral side of the locking member. The gas circuit breaker according to claim 5,
The gas circuit breaker characterized in that the locking member is cylindrical.

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