JP2007200812A - Composite type breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safe composite type breaker in which outbreak of abnormal voltage has been reduced. <P>SOLUTION: In the composite type breaker in which a vacuum breaking part 1 and gas breaking part 2 are serially-connected electrically, the gas breaking part 2 is provided with the end plate 5 fixed to that stationary contactor 3, a cylindrical body 12 in which the tip side is fixed to the end-plate 5 so that the tip side is extended on the movable contactor 4 side, and a piston 13 which is fixed to the movable contactor 4 slidably in the cylindrical body 12. By the end-plate 5, the cylindrical body 12, and the piston 13, a storing room 14 surrounding the stationary contactor 3 and the movable contactor 4 has been demarcated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power circuit breaker, and more particularly, to a composite circuit breaker in which a vacuum circuit breaker and a gas circuit breaker are electrically connected in series.

  As a high voltage circuit breaker, a puffer type gas circuit breaker has been widely used (for example, refer to Patent Document 1). When the puffer-type gas circuit breaker cuts off the current, the gas is compressed by the piston and the cylinder to generate high-pressure gas, and this high-pressure gas is blown onto the breaking arc. For this reason, the puffer-type gas circuit breaker requires enormous operating energy, and therefore, a hydraulic operating device that can obtain a large operating energy has been used.

  However, since the hydraulic operating device requires high-precision machining and is expensive, there is a strong demand for providing a more economical high-voltage circuit breaker. As a solution, a composite circuit breaker has been proposed in which a gas circuit breaker is connected in series to a vacuum circuit breaker. This composite circuit breaker allows the vacuum circuit breaker to bear the short-distance line breakage performance, which is the most severe circuit breaker duty for the gas circuit breaker, due to the characteristics of the vacuum circuit breaker that can block large currents. It is intended to reduce the operating energy of the part and to make it economical. In this example, the puffer-type gas shut-off unit shares responsibility for shut-off other than short-distance line failure (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 2002-42618.

Japanese Patent Laid-Open No. Sho 61-220229.

  In the composite circuit breaker in which the vacuum interrupter and the gas interrupter are electrically connected in series, the contact between the vacuum interrupter and the gas interrupter is opened almost simultaneously by the operating mechanism when interrupting the current. A breaking arc is generated between the contacts. In the case of interrupting a relatively small current, a current cutting phenomenon occurs in which the current is suddenly interrupted without waiting for the natural current zero point of the alternating current in the vacuum interrupting unit immediately after the contactor is opened. The current cutting generated in the vacuum interrupting part has risen without being suppressed because the gas interrupting part quickly recovers the insulation and withstands the abnormal voltage.

  The abnormal voltage described above results in inducing an excessive abnormal voltage in the load circuit when the load circuit is inductive. This abnormal voltage threatens the insulation of the power system and has a problem of impairing the reliability of the system.

  An object of the present invention is to provide a safe composite circuit breaker that eliminates the above-described drawbacks of the prior art and reduces the occurrence of abnormal voltage.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a composite circuit breaker in which a vacuum circuit breaker and a gas circuit breaker are electrically connected in series. Immediately after the opening of the child, means for reducing the gas pressure between the contacts in response to the opening operation of these contacts is provided.

  According to a second aspect of the present invention, there is provided a composite circuit breaker in which a vacuum shut-off unit and a gas shut-off unit are electrically connected in series, wherein the gas shut-off unit includes an end plate fixed to the fixed contact and a tip side. A cylindrical body fixed to the end plate so as to extend toward the movable contact; and a piston fixed to the movable contact so as to be slidable in the cylindrical body, the end plate, the cylindrical body And a storage chamber surrounding the fixed contact and the movable contact is formed by the piston.

  Furthermore, the third invention is a composite circuit breaker in which a vacuum shut-off part and a gas shut-off part are electrically connected in series, wherein the gas shut-off part includes an end plate fixed to the stationary contact, and a tip side. A cylindrical body fixed to the end plate so as to extend toward the movable contact; and a piston fixed to the movable contact so as to be slidable in the cylindrical body, the end plate, the cylindrical body And a storage chamber surrounding the stationary contact and the movable contact is formed by the piston, and a partition wall having a passage hole for the movable contact is provided in the center in the cylindrical body forming the storage chamber. It is characterized by.

  In addition, a fourth invention is characterized in that, in the third invention, the stationary contact is tubular and has a hole communicating with the storage chamber at a base portion thereof.

  Furthermore, a fifth invention is characterized in that, in the third invention, the stationary contact is tubular and has a hole communicating with an external gas space at a base portion thereof.

  The present invention provides a composite circuit breaker in which a vacuum circuit breaker and a gas circuit breaker are configured in series. The gas circuit breaker is provided with means for reducing the withstand voltage of the gas circuit breaker immediately after the contactor is opened. An abnormal voltage generated due to the current cutting phenomenon of the interrupting part is discharged through the gas interrupting part and the vacuum interrupting part to suppress the generation of the abnormal voltage, so that a safe and highly reliable composite circuit breaker is provided. Can do.

Hereinafter, embodiments of the composite circuit breaker of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a partial cross section of an embodiment of a composite circuit breaker according to the present invention. In FIG. 1, 1 is a vacuum interrupter, 2 is a gas connected in series to the vacuum interrupter 1 It is a blocking part.

  The gas blocking unit 2 includes a fixed contact 3 connected to the vacuum blocking unit 1 side and a movable contact 4 contacting and separating from the fixed contact 3. An energizing contact 6 is provided around the fixed contact 3 via a disk-shaped end plate 5 made of a conductor. Similarly, an energizing contact 8 that contacts and separates from the energizing contact 6 via a disk-shaped end plate 7 made of a conductor is provided around the movable contact 4.

  A space 9 into which the tip of the movable contact 4 enters is formed at the tip side of the fixed contact 3. The movable contact 4 is provided with an axial hole 10 formed from the tip toward the base side and a radial hole 11 provided on the base side so as to communicate with the axial hole 9. . The radial hole 11 communicates with the external gas space.

  A cylindrical body 12 made of an insulator is fixed to the inside of the end plate 5 so that the tip side thereof extends to the movable contact 4 side. A piston 13 is slidably disposed in the cylindrical body 12. The piston 13 is fixed to the outer periphery of the movable contact 4. The inner side of the end plate 5, the cylindrical body 12, and the piston 13 form a storage chamber 14 that surrounds the fixed contact 3 and the movable contact 4 that contacts and separates from the fixed contact 3. The storage chamber 14 functions to reduce the gas pressure between the stationary contact 3 and the movable contact 4 in response to the movement of the piston 13 immediately after the movable contact 4 is opened.

Next, the operation of one embodiment of the composite circuit breaker of the present invention described above will be described.
When the current is interrupted, the movable contacts of the vacuum interrupter 1 and the gas interrupter 2 are separated almost simultaneously by an operating mechanism (not shown). During this separation, a breaking arc is generated between the contacts.

  When a relatively small current is interrupted, a current cutting phenomenon occurs in the vacuum interrupter 2 immediately after the contactor is opened. When current cutting occurs in the vacuum interrupter 2, the gas interrupter 2 quickly recovers insulation and withstands abnormal voltages, so the abnormal voltage has risen up without being suppressed. When the movable contactor 4 performs the opening movement, the piston 13 fixed thereto moves together, so that the pressure in the storage chamber 14 immediately after the opening becomes extremely lower than the external pressure.

  As a result, the withstand voltage between the contacts 3 and 4 of the gas shut-off unit 2 is lowered, and the gas shut-off unit 2 is discharged because it cannot withstand the abnormal voltage caused by the current cutting of the vacuum shut-off unit 1. At this time, an abnormal voltage is applied to the vacuum interrupter 1. However, since the vacuum interrupter 1 has a low withstand voltage capability, the vacuum interrupter 1 is also discharged.

  This discharge current includes a relatively large high-frequency current due to the stray capacitance on both sides of the circuit breaker and the inductance of the busbar, but the vacuum circuit breaker 1 blocks this. Then, although an abnormal voltage tries to rise again, the gas cutoff unit 2 and the vacuum cutoff unit 1 are discharged. Such a phenomenon is repeated, and as a result, the energy stored in the inductive load at the time of cutting the current is released by this repeated discharge, so that the generation of abnormal voltage can be suppressed.

  In a large current interruption where no current cutting phenomenon occurs, the arc time becomes longer, so that a sufficient gas flows from the outside into the storage chamber 14 of the gas interruption part 2 and the gas pressure rises. Further, the gas shut-off unit 2 functions as a self-fired shut-off unit due to gas expansion caused by arc heat. Thereby, the safety | security and reliability of the composite circuit breaker which combined the vacuum circuit breaker 1 and the gas circuit breaker 2 can be improved.

FIG. 2 shows another embodiment of the composite circuit breaker according to the present invention. In FIG. 2, the same reference numerals as those in FIG. .
In this embodiment, in addition to the configuration of the embodiment shown in FIG. 1, the axial direction intermediate portion of the cylindrical body 12, that is, the front end side of the stationary contact 3, and the passage hole 15 of the movable contact 4 at the center. The partition wall 16 having the above is provided, and a narrower space 14 </ b> A is configured on the stationary contact 3 side in the storage chamber 14.

  According to this embodiment, by defining the space 14A formed on the stationary contact 3 side in the storage chamber 14 by the partition wall 16, the gas pressure drop immediately after the contact release at the time of the small current interruption is more efficiently generated. In addition to the effects that can be achieved, the safety and reliability of the combined circuit breaker in which the vacuum circuit breaker 1 and the gas circuit breaker 2 are combined can be increased as in the above-described embodiment.

FIG. 3 shows still another embodiment of the composite circuit breaker of the present invention. In FIG. 3, the same reference numerals as those in FIGS. Description is omitted.
In this embodiment, in addition to the configuration of the embodiment shown in FIG. 2, the stationary contact 3 is formed in a tubular body, and the hole 17 communicates with the space 14 </ b> A in the storage chamber 14 near the base on the end plate 5 side. Is provided.

  According to this embodiment, as in the above-described embodiment, the occurrence of abnormal voltage is suppressed, and the safety and reliability of the composite circuit breaker in which the vacuum circuit breaker 1 and the gas circuit breaker 2 are combined are improved. Can be increased. Further, at the time of interrupting a large current, the gas shut-off section 2 causes the gas heated and expanded by the arc heat to flow out from the central portion of the stationary contact 3 through the hole 17 to the space 14A in the storage chamber 14, so that it is self-sprayed. There is an action to increase the effect.

FIG. 4 shows another embodiment of the composite circuit breaker according to the present invention. In FIG. 4, the same reference numerals as those in FIG. .
In this embodiment, the fixed contact 3 is formed as a tubular body, one end thereof is fixed to the end plate 5, and 18 connected to the external gas space is provided at the portion of the end plate.

  According to this embodiment, as in the above-described embodiment, the occurrence of abnormal voltage is suppressed, and the safety and reliability of the composite circuit breaker in which the vacuum circuit breaker 1 and the gas circuit breaker 2 are combined are improved. Can be increased. In addition, the stationary contact 3 acts as a nozzle that ejects the gas in the external gas space toward the tip of the stationary contact 3 when the movable contact 4 is separated, thereby enhancing the arc blowing effect.

It is a block diagram which shows one Embodiment of the composite type circuit breaker of this invention in a partial cross section. It is a block diagram which shows other embodiment of the composite type circuit breaker of this invention in a partial cross section. It is a block diagram which shows further another embodiment of the composite circuit breaker of this invention in a partial cross section. It is a block diagram which shows other embodiment of the composite type circuit breaker of this invention in a partial cross section.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum interruption | blocking part 2 Gas interruption | blocking part 3 Fixed contact 4 Movable contact 5 End plate 6 Current contact 7 End plate 8 Current contact 9 Cavity 10 Axial hole 11 Radial hole 12 Tubular body 13 Piston 14 Reservoir 15 Passage hole 16 Bulkhead

Claims (5)

  In a composite circuit breaker in which a vacuum shut-off unit and a gas shut-off unit are electrically connected in series, the gas shut-off unit is opened immediately after the movable contact with respect to the stationary contact is opened. A composite circuit breaker comprising means for reducing the gas pressure between the contacts in response to the operation.   In a composite circuit breaker in which a vacuum shut-off part and a gas shut-off part are electrically connected in series, the gas shut-off part includes an end plate fixed to the fixed contact and a tip side extending to the movable contact. A cylindrical body fixed to the end plate and a piston fixed to the movable contact so as to be slidable in the cylindrical body, and the fixed contact by the end plate, the cylindrical body and the piston. And a storage chamber surrounding the movable contact.   In a composite circuit breaker in which a vacuum shut-off part and a gas shut-off part are electrically connected in series, the gas shut-off part includes an end plate fixed to the fixed contact and a tip side extending to the movable contact. A cylindrical body fixed to the end plate and a piston fixed to the movable contact so as to be slidable in the cylindrical body, and the fixed contact by the end plate, the cylindrical body and the piston. And a storage chamber surrounding the movable contact, and a partition wall having a passage hole for the movable contact in the center is provided in the cylindrical body forming the storage chamber. .   4. The composite circuit breaker according to claim 3, wherein the stationary contact has a tubular shape, and has a base communicating with a hole communicating with the storage chamber.   4. The composite circuit breaker according to claim 3, wherein the stationary contact is tubular, and has a hole communicating with an external gas space at a base portion thereof.

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