JP2012190704A - Direct-current circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a direct-current circuit breaker capable of reducing electromagnetic force applied between a main circuit breaker and a sub circuit breaker and restraining the main circuit breaker and the sub circuit breaker from increasing in size.SOLUTION: There is provided a direct-current circuit breaker comprising: a main circuit breaker 12 including a main circuit-breaking portion capable of interrupting vacuum arc discharge which is along an axis direction; a sub circuit breaker 13 including a sub circuit-breaking portion capable of interrupting vacuum arc discharge which is along the axis direction and connected in series to the main circuit breaker; and a commutating circuit and an energy absorbing element connected in parallel to the main circuit breaker 12. The main circuit breaker and the sub circuit breaker are positioned at a distance from each other in the axis direction.

Description

  Embodiments described herein relate generally to a DC circuit breaker.

  Generally, a DC circuit breaker is provided in a DC circuit such as an electric railway feeder circuit. The DC circuit breaker has a main circuit breaker and a sub circuit breaker connected in series. The sub circuit breaker is provided on the power source side of the DC power source of the DC circuit, and the main circuit breaker is provided on the load side of the DC circuit. The DC circuit breaker interrupts accident currents and energized currents.

  The main circuit breaker is connected in parallel with an energy absorption element that absorbs energy stored in the system when the fault current is interrupted and a commutation circuit. The commutation circuit includes a commutation capacitor, a commutation reactor, and a commutation switch connected in series.

When interrupting the current flowing through the DC circuit, the main circuit breaker is opened (OFF), the commutation switch is closed (ON), the commutation capacitor is discharged, and the current flowing through the main circuit breaker (in the DC circuit) A commutation current in the opposite direction to the flowing current). Thereby, the electric current which flows into a main circuit breaker can be made into 0, and can be interrupted | blocked. When the current flowing through the main circuit breaker becomes zero, the current flows through the energy absorbing elements connected in parallel to the main circuit breaker, and thus the current is attenuated.
On the other hand, the secondary circuit breaker is opened (OFF) after closing the commutation switch, and when the current flowing from the power source side to the load side is attenuated to zero, the circuit breaker is completed.

  The main circuit breaker has a main circuit breaker including a main vacuum valve and an open / close electrode sealed in the main vacuum valve. The sub circuit breaker has a sub circuit breaker including a sub vacuum valve and an open / close electrode sealed in the sub vacuum valve. The main vacuum valve and the sub vacuum valve are provided next to each other.

  The main circuit breaker is opened (OFF) by a high-speed opening mechanism in the case of an accidental current interruption, and by a main circuit breaker normal operation mechanism in the case of load current interruption or no-load opening. The secondary circuit breaker is opened (OFF) / closed (ON) by the secondary circuit breaker normal operation mechanism.

Japanese Patent No. 4357505

  By the way, in the DC circuit breaker, the interruption current when an accident occurs causes a vacuum arc discharge to be generated in the open / close electrodes in the adjacent main vacuum valve and sub vacuum valve. For this reason, a large electromagnetic force is generated from both the vacuum arc discharge at the open / close electrode in the main vacuum valve and the vacuum arc discharge at the open / close electrode in the sub vacuum valve.

Thereby, the main circuit breaker, the sub circuit breaker, the structure supporting these, etc. need to have mechanical strength that can withstand the electromagnetic force.
Furthermore, the electromagnetic force generated from the vacuum arc discharge at the open / close electrode in the main vacuum valve acts on the vacuum arc discharge at the open / close electrode in the sub vacuum valve, and the vacuum at the open / close electrode in the sub vacuum valve. The electromagnetic force generated from the arc discharge acts on the vacuum arc discharge at the open / close electrode in the main vacuum valve. In order to obtain the required breaking performance, it is necessary to increase the size of the switching electrodes of the main breaker and the sub breaker.

  The present invention has been made in view of the above points, and an object thereof is to reduce the electromagnetic force acting between the main circuit breaker and the sub circuit breaker, and to increase the size of the main circuit breaker and the sub circuit breaker. It is providing the DC circuit breaker which can be suppressed.

The DC circuit breaker according to an embodiment is
A main circuit breaker having a main circuit breaker capable of interrupting vacuum arc discharge along the axial direction;
A secondary circuit breaker having a secondary circuit breaker capable of blocking vacuum arc discharge along the axial direction, and connected in series to the main circuit breaker;
A commutation circuit connected in parallel to the main circuit breaker;
An energy absorbing element connected in parallel to the main circuit breaker,
The main blocking part and the sub blocking part are characterized by being shifted in the axial direction.

FIG. 1 is a schematic configuration diagram showing an electric railway feeding circuit including a DC circuit breaker according to an embodiment. FIG. 2 is a block diagram showing the DC circuit breaker. FIG. 3 is a side view showing a part of the DC circuit breaker of Example 1 according to the embodiment. FIG. 4 is a side view showing a part of the DC circuit breaker of Example 3 according to the embodiment. FIG. 5 is a top view showing a part of the DC circuit breaker of Example 4 according to the embodiment. FIG. 6 is a top view showing a part of the DC circuit breaker of Example 5 according to the above embodiment. FIG. 7 is a top view showing a part of the DC circuit breaker of Example 6 according to the above embodiment. FIG. 8 is a diagram for explaining the operation of the DC circuit breaker according to the above-described embodiment, and is a graph showing a change in the value of the current flowing through the DC circuit breaker with respect to time.

  Hereinafter, a DC circuit breaker according to an embodiment will be described in detail with reference to the drawings. In this embodiment, the case where the DC circuit breaker is provided in an electric railway feeder circuit as a DC circuit will be described.

  As shown in FIG. 1, the electric railway feeding circuit includes a DC circuit breaker 20, a power supply 21 that is a DC power supply, and a load 22. The DC breaker 20 is connected in series with the power source 21 and the load 22. In this embodiment, the load 22 is an electric vehicle having a vehicle body, a pantograph, wheels, and the like. The DC breaker 20 is electrically connected to the pantograph of the load 22 via an overhead wire 23 and the like. The power source 21 is electrically connected to the wheel of the load 22 that is in contact with the rail 24 via the rail 24 or the like.

  As shown in FIG. 2, the DC circuit breaker 20 includes a main circuit breaker 12, a sub circuit breaker 13, an energy absorbing element 14, a commutation circuit 15, a high-speed opening mechanism 3, and a main circuit breaker 12. A normal operation mechanism 4 and a normal operation mechanism 5 for the auxiliary circuit breaker 13 are provided.

  The main circuit breaker 12 and the sub circuit breaker 13 are connected in series. The main circuit breaker 12 is connected to the load 22 side, and the sub circuit breaker 13 is connected to the power source 21 side. The energy absorbing element 14 is connected to the main circuit breaker 12 in parallel. In this embodiment, the energy absorbing element 14 is formed of a resistor. The commutation circuit 15 includes a commutation switch 16, a commutation capacitor 17, and a commutation reactor 18. The commutation switch 16, the commutation capacitor 17, and the commutation reactor 18 are connected in series. The commutation capacitor 17 is charged to a predetermined voltage by a charging device (not shown).

Next, the DC circuit breakers 20 of Examples 1 to Examples according to this embodiment will be described.
Example 1
As shown in FIGS. 2 and 3, the main circuit breaker 12 has a main vacuum valve 1, and a fixed electrode and a movable electrode sealed in the main vacuum valve 1. The fixed electrode and the movable electrode form a main interruption part capable of interrupting the vacuum arc discharge generated along the axial direction in which they are opposed to each other. In this embodiment, the axial direction is the first direction Z.

  The sub circuit breaker 13 includes the sub vacuum valve 2 and a fixed electrode and a movable electrode sealed in the sub vacuum valve 2. The fixed electrode and the movable electrode form a sub-blocking portion that can block vacuum arc discharge that occurs along the axial direction (first direction Z) in which they are opposed.

  In the main circuit breaker 12, a first connection conductor 31 is connected to the fixed electrode, and a second connection conductor 32 is connected to the movable electrode. In the sub-circuit breaker 13, a third connection conductor 33 is connected to the fixed electrode, and a fourth connection conductor 34 is connected to the movable electrode. The fourth connection conductor 34 includes a first conductor 34a connected to the movable electrode and a second conductor 34b connected to the first conductor 34a.

The first to fourth connection conductors 31 to 34 are highly rigid. In this embodiment, the first connection conductor 31, the third connection conductor 33, and the second conductor 34b are formed of a copper plate, and the second connection conductor 32 and the first conductor 34a are formed of a copper shaft.
The first connector 6 is connected to the first connection conductor 31, and the second connector 7 is connected to the fourth connection conductor 34 (second conductor 34 b).

  In this embodiment, the 1st relay conductor 8 and the 2nd relay conductor 9 are for connecting both the energy absorption element 14 and the commutation circuit 15 to the main circuit breaker 12 in parallel. The first relay conductor 8 is connected to the first connection conductor 31, and the second relay conductor 9 is connected to the third connection conductor 33.

  The first relay conductor 8 and the second relay conductor 9 may be for connecting one of the energy absorbing element 14 and the commutation circuit 15 to the main circuit breaker 12 in parallel. In this case, the other of the energy absorption element 14 and the commutation circuit 15 may be connected in parallel to the main circuit breaker 12 using another relay conductor.

  The high-speed opening mechanism 3 and the normal operation mechanism 4 can switch the movable electrode of the main circuit breaker 12 between an opening (OFF) position and a closing (ON) position by moving the second connection conductor 32. The normal operation mechanism 5 can switch the movable electrode of the auxiliary circuit breaker 13 between the open (OFF) position and the closed (ON) position by moving the fourth connection conductor 34 (first conductor 34a).

The main circuit breaker 12 of the main circuit breaker 12 and the sub circuit breaker 13 of the sub circuit breaker 13 are shifted from each other along the axial direction (first direction Z). In this embodiment, the main circuit breaker of the main circuit breaker 12 and the sub circuit breaker of the sub circuit breaker 13 sandwich the third connection conductor 33 extending in a direction orthogonal to the axial direction (first direction Z). Since it is located up and down, it can be said that it is located completely displaced in the axial direction (first direction Z).
In addition, the interruption | blocking method of the interruption | blocking current 10 at the time of the accident by the DC circuit breaker 20 is mentioned later.

(Example 2)
As shown in FIGS. 2 and 3, the movable electrode of the main circuit breaker 12 is connected to the second connection conductor 32 via a slide contact or a flexible contact. Similarly, the movable electrode of the sub circuit breaker 13 is also connected to the fourth connection conductor 34 (first conductor 34a) via a slide contact or a flexible contact.
In addition to the above, the DC breaker 20 of the second embodiment is formed in the same manner as the DC breaker 20 of the first embodiment.

(Example 3)
As shown in FIGS. 2 and 4, the first relay conductor 8 and the second relay conductor 9 are located between the first connection conductor 31 and the second connection conductor 32 and extend in parallel to each other. When the current 11 flows through the energy absorbing element 14, the direction of the current 11 flowing through the first relay conductor 8 and the direction of the current 11 flowing through the second relay conductor 9 are antiparallel.
In addition to the above, the DC breaker 20 of the third embodiment is formed in the same manner as the DC breaker 20 of the second embodiment.

Example 4
As shown in FIGS. 2 and 5, the first connector 6 can be connected in a connection direction orthogonal to the axial direction (first direction Z). Similarly, the second connector 7 can be connected in the connection direction. In this embodiment, the connection direction is the second direction Y.

  The first connection conductor 31, the third connection conductor 33, the second conductor 34b, the first relay conductor 8, and the second relay conductor 9 extend in parallel to the connection direction (second direction Y). The connectors of the first relay conductor 8 and the second relay conductor 9 can also be connected in the connection direction.

The main circuit breaker 12 (main vacuum valve 1) and the sub circuit breaker 13 (sub vacuum valve 2) are in a direction (third direction X) orthogonal to the connection direction (second direction Y) and the axial direction (first direction Z). It is located in the position.
In addition to the above, the DC breaker 20 of the fourth embodiment is formed in the same manner as the DC breaker 20 of the third embodiment.

(Example 5)
As shown in FIGS. 2 and 6, the main circuit breaker 12 (main vacuum valve 1) and the sub circuit breaker 13 (sub vacuum valve 2) are shifted in the connection direction (second direction Y).
In addition to the above, the DC breaker 20 of the fifth embodiment is formed in the same manner as the DC breaker 20 of the fourth embodiment.

(Example 6)
2 and 7, the main circuit breaker 12 (main vacuum valve 1) and the sub circuit breaker 13 (sub vacuum valve 2) are arranged in the third direction in the direction orthogonal to the axial direction (first direction Z). The position is shifted in the direction inclined from X and the connection direction (second direction Y).

  In addition to the above, the DC breaker 20 of the sixth embodiment is formed in the same manner as the DC breaker 20 of the fourth embodiment.

Next, when an accident current occurs in the electric railway feeder circuit due to the occurrence of an accident, by using the DC circuit breaker 20 of this embodiment, the interruption current 10 flowing through the main circuit breaker 12 and the sub circuit breaker 13 is reduced. A method of blocking will be described.
As shown in FIG. 1, FIG. 2, FIG. 3, FIG. 8 and FIG. 8, when an excessive fault current flows in the electric railway power circuit, control is performed from a control unit (not shown) to the high-speed opening mechanism 3 at timing t1. By giving a signal, the high-speed opening mechanism 3 can switch the movable electrode of the main circuit breaker 12 to the opening position.

  Thereafter, at timing t2, a control signal is given from the control unit to the commutation switch 16, and the commutation switch 16 is switched to ON. The commutation capacitor 17 starts discharging and energizes a commutation current in a direction opposite to the current flowing through the main circuit breaker 12 (current flowing through the electric railway feeding circuit). Thereby, in the subsequent timing t3, the 1st electric current (breaking current) which flows into the main circuit breaker 12 can be set to 0, and it can interrupt | block. When the first current flowing through the main circuit breaker 12 becomes zero, the current 11 flows through the energy absorbing element 14 connected in parallel to the main circuit breaker 12, and thus the current is attenuated.

On the other hand, after the commutation switch 16 is turned ON, the normal operation mechanism 5 switches the movable electrode of the auxiliary circuit breaker 13 to the open position by giving a control signal to the normal operation mechanism 5 from the control unit. Can do. Since the second current (breaking current) flowing through the sub circuit breaker 13 is attenuated by the action of the energy absorbing element 14, the second current flowing through the sub circuit breaker 13 can be set to 0 at the timing t4 and blocked.
As described above, the interruption of the interruption current 10 flowing through the main circuit breaker 12 and the sub circuit breaker 13 is completed.

  According to the DC circuit breaker 20 according to the embodiment configured as described above, the DC circuit breaker 20 includes the main circuit breaker 12, the sub circuit breaker 13, the energy absorbing element 14, and the commutation circuit 15. I have. The main circuit breaker 12 has a main circuit breaker that can block vacuum arc discharge along the axial direction. The sub circuit breaker 13 has a sub circuit breaker that can block vacuum arc discharge along the axial direction, and is connected to the main circuit breaker 12 in series. The energy absorbing element 14 and the commutation circuit 15 are connected to the main circuit breaker 12 in parallel.

  (1) In the first to sixth embodiments, the main circuit breaker of the main circuit breaker 12 and the sub circuit breaker of the sub circuit breaker 13 are shifted from each other along the axial direction (first direction Z). Yes. Since the main circuit breaker 12 of the main circuit breaker 12 and the sub circuit breaker 13 of the sub circuit breaker 13 are not located next to each other, the influence of electromagnetic force applied from the main circuit breaker 12 to the sub circuit breaker 13 when an accident occurs Vice versa, and vice versa, the influence of the electromagnetic force exerted on the main circuit breaker 12 from the sub circuit breaker 13 can be reduced.

  Thereby, it can reduce that the main circuit breaker 12, the sub circuit breaker 13, etc. are destroyed or vibrate, and the stable operation of the DC circuit breaker 20 can be ensured. In addition, the required mechanical strength can be reduced without significant modification of the DC circuit breaker 20.

  Further, the electromagnetic force from the main circuit breaker 12 acts on the vacuum arc discharge in the sub circuit breaker 13 and the electromagnetic force from the sub circuit breaker 13 acts on the vacuum arc discharge in the main circuit breaker 12 is reduced. be able to. For this reason, the enlargement of the size of the fixed electrode and movable electrode of the main circuit breaker 12 and the sub circuit breaker 13 can be suppressed.

(2) In Example 2 to Example 6, the movable electrode of the main circuit breaker 12 is connected to the second connection conductor 32 via a slide contact or a flexible contact. For this reason,
It is possible to make it difficult to transmit vibration from the main circuit breaker 12 to the sub circuit breaker 13 and from the sub circuit breaker 13 to the main circuit breaker 12 at the time of opening / closing. Therefore, the required mechanical strength can be further reduced.

  (3) In the third to sixth embodiments, the direction of the current 11 flowing through the first relay conductor 8 and the direction of the current 11 flowing through the second relay conductor 9 can be made antiparallel. Since the electromagnetic force generated by the current 11 flowing through the first relay conductor 8 and the electromagnetic force generated by the current 11 flowing through the second relay conductor 9 cancel each other, the electromagnetic force acting on the sub-breaker 13 is further reduced. can do.

  (4) Since the size of the connection direction (second direction Y) in the fourth embodiment and the third direction X in the fifth embodiment can be reduced, the DC circuit breaker 20 can be reduced in size.

  From the above, the DC circuit breaker 20 that can reduce the electromagnetic force acting between the main circuit breaker 12 and the sub circuit breaker 13 and can suppress increase in size of the main circuit breaker and the sub circuit breaker. Obtainable.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

For example, the main circuit breaker 12 and the sub circuit breaker 13 may be located along the axial direction.
For the connection between the main circuit breaker 12 and the sub circuit breaker 13, the third connection conductor 33 is connected to the second connection conductor 32, but is not limited to this, and various modifications are possible. The first connection conductor 31 may be connected to the fourth connection conductor 34.

The DC circuit breaker is not limited to the electric railway feeder circuit but can be applied to various DC circuits.
The present invention is not limited to the DC circuit breaker, but can be applied to various DC circuit breakers.

  DESCRIPTION OF SYMBOLS 1 ... Main vacuum valve, 2 ... Sub vacuum valve, 3 ... High-speed opening mechanism, 4 ... Normal operation mechanism, 5 ... Normal operation mechanism, 6 ... 1st connector, 7 ... 2nd connector, 8 ... 1st relay conductor, DESCRIPTION OF SYMBOLS 9 ... 2nd relay conductor, 10 ... Breaking current, 11 ... Current, 12 ... Main circuit breaker, 13 ... Sub-circuit breaker, 14 ... Energy absorption element, 15 ... Commutation circuit, 16 ... Commutation switch, 17 ... Commutation Capacitors, 18 ... commutation reactors, 20 ... DC circuit breakers, 31 ... first connection conductor, 32 ... second connection conductor, 33 ... third connection conductor, 34 ... fourth connection conductor, 34a ... first conductor, 34b ... 2nd conductor, Z ... 1st direction, Y ... 2nd direction, X ... 3rd direction.

Claims (6)

A main circuit breaker having a main circuit breaker capable of interrupting vacuum arc discharge along the axial direction;
A secondary circuit breaker having a secondary circuit breaker capable of blocking vacuum arc discharge along the axial direction, and connected in series to the main circuit breaker;
A commutation circuit connected in parallel to the main circuit breaker;
An energy absorbing element connected in parallel to the main circuit breaker,
The DC circuit breaker characterized in that the main circuit breaker and the sub circuit breaker are offset from each other in the axial direction. A first connection conductor connected to a fixed electrode forming the main blocking portion;
A second connecting conductor connected to the movable electrode forming the main blocking portion;
A third connection conductor connected to the fixed electrode forming the sub-blocking portion;
A fourth connection conductor connected to the movable electrode forming the sub-blocking portion, and
The DC circuit breaker according to claim 1, wherein the third connection conductor is connected to the second connection conductor, or the first connection conductor is connected to the fourth connection conductor. A first connection conductor connected to a fixed electrode forming the main blocking portion;
A second connecting conductor connected to the movable electrode forming the main blocking portion;
A first circuit breaker for connecting the commutation circuit in parallel to the main circuit breaker, for connecting the energy absorption element in parallel, or for connecting both the commutation circuit and the energy absorption element in parallel. A relay conductor and a second relay conductor,
2. The DC circuit breaker according to claim 1, wherein the first relay conductor and the second relay conductor are located between the first connection conductor and the second connection conductor and extend in parallel with each other. . A first connection conductor connected to a fixed electrode forming the main blocking portion;
A second connecting conductor connected to the movable electrode forming the main blocking portion;
A third connection conductor connected to the fixed electrode forming the sub-blocking portion;
A fourth connection conductor connected to the movable electrode forming the sub-blocking portion;
A first connector connected to the first connection conductor or the second connection conductor and connectable in a connection direction;
A second connector connected to the third connection conductor or the fourth connection conductor and connectable in the connection direction;
2. The DC circuit breaker according to claim 1, wherein the main circuit breaker and the sub circuit breaker are shifted from each other in a direction orthogonal to the connection direction and the axial direction. A first connection conductor connected to a fixed electrode forming the main blocking portion;
A second connecting conductor connected to the movable electrode forming the main blocking portion;
A third connection conductor connected to the fixed electrode forming the sub-blocking portion;
A fourth connection conductor connected to the movable electrode forming the sub-blocking portion;
A first connector connected to the first connection conductor or the second connection conductor and connectable in a connection direction;
A second connector connected to the third connection conductor or the fourth connection conductor and connectable in the connection direction;
The DC circuit breaker according to claim 1, wherein the main circuit breaker and the sub circuit breaker are shifted from each other in the connection direction. A first connection conductor connected to a fixed electrode forming the main blocking portion;
A second connecting conductor connected to the movable electrode forming the main blocking portion;
A third connection conductor connected to the fixed electrode forming the sub-blocking portion;
A fourth connection conductor connected to the movable electrode forming the sub-blocking portion;
A first connector connected to the first connection conductor or the second connection conductor and connectable in a connection direction;
A second connector connected to the third connection conductor or the fourth connection conductor and connectable in the connection direction;
The main circuit breaker and the sub circuit breaker are located in a direction perpendicular to the axial direction and shifted from the connection direction, the direction orthogonal to the axial direction, and the direction inclined from the connection direction. The DC circuit breaker according to claim 1.

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