JP2014175064A - Gas-insulated switchgear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress diffusion of arc during the switching operation of a gas-insulated switchgear.SOLUTION: A gas-insulated switchgear 1 is constituted by providing a movable contact 2 and a fixed contact part 3 in a space filled with insulating gas. The movable contact 2 is fixed to a piston 5 movable in a cylinder 4. The piston 5 partitions the interior of the cylinder 4 into a first cylinder chamber 4a and a second cylinder chamber 4b. A communication hole 5a communicating the first cylinder chamber 4a and second cylinder chamber 4b is formed in the piston 5. A first closing member 7 closing the communication hole 5a is provided on the first cylinder chamber 4a side of the piston 5, and a second closing member 8 closing the communication hole 5a is provided on the second cylinder chamber 4b side of the piston 5.

Description

  The present invention relates to a gas insulated switch having improved arc extinguishing performance by an insulating gas flow.

As a gas insulated switchgear provided in a substation or the like, a gas insulated switchgear using an insulating medium having high insulation and high arc extinguishing ability such as SF ₆ and dry air is widely used.

  A small current switching capability may be required for a disconnect switch or a ground switch stored in a gas insulated switchgear. For example, a grounding switch used for a line is required to have a performance of cutting off an electromagnetic induction current during a grounding “off” operation and a performance of discharging a cable residual charge during the grounding “on” operation. .

  Generally, when the electromagnetic induction current is cut off (grounding “off” operation), a suction puffer method is used in which a gas flow is generated by sucking an insulating gas, and the arc is controlled and extinguished by this gas flow. (For example, Patent Documents 1 and 2). In this case, since the decomposition product generated by the arc can also be sucked, there is an advantage that the decomposition product is not diffused.

  On the other hand, in the case of cable residual charge discharge (grounding “on” operation), when the movable contact approaches the fixed contact during the operation, the cable residual charge starts to discharge, and an arc is generated between the movable contact tip and the fixed arcing. Will occur.

JP-A-8-2222096 JP-A-7-122165

  However, in the conventional suction puffer system, the insulating gas is blown during the grounding “on” operation, as opposed to the grounding “off” operation, so that the arc is diffused by the gas flow, and the arc cannot be controlled. There is a risk that the arc will ignite and damage the fixed contact.

  In addition, since the decomposition product sucked during the grounding “off” operation is sprayed at the same time, the decomposition product adheres to the fixed contact, which may increase the contact resistance.

  In view of the above circumstances, an object of the present invention is to provide a gas-insulated switch that contributes to suppressing arc diffusion during a switching operation.

  A gas-insulated switch of the present invention that achieves the above object is provided in a cylinder so as to be slidable. The piston is partitioned into two chambers, and a communication hole for communicating the two chambers is formed. Is fixed to the piston and provided with a cylindrical movable contact portion having a vent hole communicating with the communication hole, and opposite to the other end of the movable contact portion, and the other end portion of the movable contact portion is separated from and connected to the piston. A gas-insulated switch having a fixed contact portion, and a space between the cylinder and the fixed contact portion is filled with an insulating gas, and the cylinder on the fixed contact portion side according to the movement of the piston A first closing member that opens and closes the chamber and the communication hole, and a second closing member that opens and closes the other cylinder chamber and the communication hole in accordance with the movement of the piston.

  ADVANTAGE OF THE INVENTION According to this invention, it can contribute to the spreading | diffusion suppression of the arc at the time of switching operation of a gas insulated switch.

It is principal part sectional drawing of the gas insulated switch which concerns on embodiment of this invention. (A) The expanded sectional view of the piston part of the gas insulated switch which concerns on embodiment of this invention, (b) The figure which looked at the piston part of the gas insulated switch which concerns on embodiment of this invention from the axial direction. It is explanatory drawing explaining the time of "OFF" operation | movement of the gas insulated switch which concerns on embodiment of this invention. It is explanatory drawing explaining the time of "ON" operation | movement of the gas insulated switch which concerns on embodiment of this invention.

  A gas insulated switch according to an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram schematically illustrating a gas insulated switch 1 according to an embodiment of the present invention. As shown in FIG. 1, the gas insulated switch 1 is configured by providing a movable contact 2 and a fixed contact portion 3 in a space filled with an insulating gas.

  The movable contact 2 is a hollow cylindrical member. That is, the movable contact 2 is formed with a vent hole 2 a having an open end along the axis of the movable contact 2. The movable contact 2 is provided so that the tip thereof faces the fixed contact portion 3, and a piston 5 that can move in the cylinder 4 is fixed to the base end portion.

  The piston 5 is provided so as to partition the inside of the cylinder 4 into a first cylinder chamber 4a and a second cylinder chamber 4b. A shaft 6 of the piston 5 is provided on the surface of the piston 5 opposite to the surface on which the movable contact 2 is provided, and the piston 5 slides in the cylinder 4 by moving the shaft 6 in the axial direction.

  As shown in FIG. 2A, the piston 5 is formed with a communication hole 5a for communicating the first cylinder chamber 4a and the second cylinder chamber 4b. The communication hole 5a is formed in the movable contact 2, respectively. The vent hole 2a communicated. FIG. 2B shows an example of the communication hole 5 a formed in the piston 5. As shown in FIG. 2B, a plurality of communication holes 5 a penetrating the piston 5 are formed on the circumference centered on the axis of the piston 5. In addition, since the communication hole 5a should just communicate the 1st cylinder chamber 4a and the 2nd cylinder chamber 4b, an arrangement form and the number formed are not limited to embodiment.

  As shown in FIG. 2 (a), the first blocking member 7 and the surface of the piston 5 on the first cylinder chamber 4a side and the second cylinder chamber 4b side are formed on the surface where the communication hole 5a of the piston 5 is formed. A second closing member 8 is provided.

  The first closing member 7 and the second closing member 8 are, for example, circular plate-like members in which a hole through which the movable contact 2 or the shaft 6 is inserted is formed at the center, and the communication hole 5a of the piston 5 is formed. The communication hole 5a is closed by contacting the surface.

  A locking portion 7a that restrains the movement of the first closing member 7 from the surface of the piston 5 with which the first closing member 7 comes into contact in a sliding direction of the piston 5 away from the thickness of the first closing member 7. Is provided. Similarly, a mechanism that suppresses the movement of the second closing member 8 at a position away from the surface of the piston 5 with which the second closing member 8 abuts in the sliding direction of the piston 5 and away from the thickness of the second closing member 8. A stop 8a is provided. The first closing member 7 and the second closing member 8 are held movably in the sliding direction of the piston 5 by the locking portions 7a and 8a.

  As shown in FIG. 1, the fixed contact portion 3 includes a fixed-side arcing 9 that is inserted through the vent hole 2 a of the movable contact 2 and a fixed-side contact 10 that contacts the outer surface of the movable contact 2. A shield 11 is provided between the fixed contact 10 and the distal end of the movable contact 2, and arcing from the movable contact 2 to the fixed contact 10 is suppressed.

  Next, with reference to FIGS. 3 and 4, the operation of the gas insulated switch 1 according to the embodiment of the present invention will be described in detail.

  As shown in FIG. 3, when the movable contact 2 is separated from the state where the movable contact 2 and the fixed contact 10 are in contact with each other, the movable contact 2 and the fixed contact 10 are separated while being energized. An arc is generated between the movable contact 2 and the fixed-side arcing 9.

  At this time, the piston 5 and the movable contact 2 move in a direction away from the fixed contact portion 3 (left direction in FIG. 3), but the first closing member 7 tries to stop in place according to the law of inertia. As a result, the first closing member 7 comes into contact with the locking portion 7 a, and a gap is generated between the piston 5 and the first closing member 7. Further, since the first cylinder chamber 4a is widened by the movement of the piston 5, the pressure in the first cylinder chamber 4a becomes lower than the pressure in the vent hole 2a, and the insulating gas between the fixed contact portion 3 and the movable contact 2 is reduced. The air is sucked into the first cylinder chamber 4a through the vent hole 2a. That is, a gas flow is generated between the movable contact 2 and the fixed contact portion 3 so as to be sucked into the vent hole 2a of the movable contact 2 (the gas flow is indicated by an arrow in the figure).

  Since the second closing member 8 tries to stop in place according to the law of inertia, the second closing member 8 comes into contact with the piston 5 so as to be pressed by the movement of the piston 5. Further, as the piston 5 moves, the second cylinder chamber 4b becomes narrower, so that the pressure in the second cylinder chamber 4b becomes higher than the pressure in the vent hole 2a. As a result, the second cylinder chamber 4b and the vent hole 2a are closed by the second closing member 8. Then, after the movable contact 2 is separated from the fixed contact 10, the insulating gas leaks from the second cylinder chamber 4b to the vent hole 2a and the first cylinder chamber 4a as time elapses, and passes through the second cylinder chamber 4b. The pressures in the pores 2a and the first cylinder chamber 4a are equal.

  As shown in FIG. 4, when the movable contact 2 is brought into contact with the fixed contact 10 from the state where the movable contact 2 and the fixed contact 10 are separated from each other, the discharge of the cable residual charge starts, and the tip of the movable contact 2 and the fixed side An arc is generated between arcing 9.

  At this time, the piston 5 and the movable contact 2 move in a direction approaching the fixed contact portion 3 (the right direction in FIG. 4), but the second closing member 8 tries to stop in place according to the law of inertia. As a result, the second closing member 8 comes into contact with the locking portion 8a, and a gap is generated between the piston 5 and the second closing member 8. Furthermore, since the second cylinder chamber 4b is widened by the movement of the piston 5, the pressure in the second cylinder chamber 4b becomes lower than the pressure in the vent hole 2a, and the insulating gas between the fixed contact portion 3 and the movable contact 2 is reduced. The air is sucked into the second cylinder chamber 4b through the vent hole 2a. That is, a gas flow is generated between the movable contact 2 and the fixed contact portion 3 so as to be sucked into the vent hole 2a of the movable contact 2 (the gas flow is indicated by an arrow in the figure).

  Since the first closing member 7 tries to stop in place according to the law of inertia, the first closing member 7 comes into contact with the piston 5 so as to be pressed by the movement of the piston 5. Furthermore, since the 1st cylinder chamber 4a becomes narrow with the movement of piston 5, the pressure of the 1st cylinder chamber 4a becomes higher than the pressure in vent hole 2a. As a result, the space between the first cylinder chamber 4a and the vent hole 2a is closed by the first closing member 7. Then, after the movable contact 2 comes into contact with the fixed contact 10, the insulating gas leaks from the first cylinder chamber 4a to the vent hole 2a and the second cylinder chamber 4b as time elapses, and the first cylinder chamber 4a and the vent hole The pressures in 2a and the second cylinder chamber 4b become equal.

  As described above, according to the specific embodiment, according to the gas insulated switch of the present invention, the insulating gas is supplied into the cylinder regardless of whether the switch is set to “ON” or “OFF”. Can inhale. As a result, the generated arc is generated along the flow of the insulating gas, and an excellent small current switching performance with controlled arc can be obtained. That is, it is possible to provide a gas insulated switch having an excellent small current switching performance with a simple configuration in which a valve is added to the piston.

  Whether the switch is set to “ON” or “OFF”, the decomposition product caused by the arc can be sucked to prevent the decomposition product from adhering to the contact and spreading.

  Further, by preventing arc diffusion, it is not necessary to take measures such as adding arc-resistant metal to the shield or the fixed contact, and the cost of the gas insulated switch can be reduced.

  The gas-insulated switch according to the present invention is not limited to the above-described embodiment, and can be appropriately designed and modified within a range that does not impair the operation and effect thereof. It belongs to the technical scope of gas insulated switchgear. For example, in the embodiment, a description has been given of a mode in which one closing member that opens and closes the communication hole formed in the piston and each cylinder chamber has been described, but a mode in which a blocking member (opening / closing valve) is provided in each communication hole. It is good.

1 ... gas insulated switch 2 ... movable contact (movable contact part)
2a ... vent 3 ... fixed contact portion 4 ... cylinder 4a ... first cylinder chamber 4b ... second cylinder chamber 5 ... piston 5a ... communication hole 6 ... shaft 7 ... first closing members 7a, 8a ... locking portion 8 ... first 2 Closing member 9 ... Fixed side arcing 10 ... Fixed side contact 11 ... Shield

Claims (2)

A piston that is slidably provided in the cylinder, partitions the inside of the cylinder into two chambers, and has a communication hole that communicates the two chambers;
A cylindrical movable contact portion having one end fixed to the piston and having a vent hole communicating with the communication hole;
A fixed contact portion provided opposite to the other end of the movable contact portion, the other end portion of the movable contact portion being separated from, and
A gas insulated switch filled with an insulating gas in a space between the cylinder and the fixed contact portion,
A first closing member that opens and closes the cylinder chamber on the fixed contact portion side and the communication hole according to the movement of the piston;
A gas-insulated switch comprising the other cylinder chamber and a second closing member that opens and closes the communication hole in accordance with the movement of the piston. The communication hole is formed through the piston in the sliding direction of the piston;
The first closing member can be brought into contact with one surface where the communication hole of the piston is formed, and can be moved in the sliding direction of the piston.
2. The gas according to claim 1, wherein the second closing member is provided so as to be able to come into contact with the other surface on which the communication hole of the piston is formed and to be movable in a sliding direction of the piston. Insulated switch.

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