JP2002334642A - Direct current vacuum circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a direct current vacuum circuit breaker with improved conduction property and increased conduction capacity, which can efficiently radiate Joule heat generated at a vacuum valve, and shorten the time of breaking by enlarging radiation area. SOLUTION: A fixed side terminal 2 of a vacuum valve is supported by and fixed to a first metal frame 8, and the first metal frame surrounds the vacuum valve 1, and the first metal frame 8 is fixed to a truck 6 through a second metal frame 9 to which, an insulation member 7 and a movable side terminal 3 is connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC vacuum circuit breaker which detects an abnormal current in a DC circuit and cuts off the current.
The present invention relates to a frame structure for supporting and fixing a vacuum valve.

[0002]

2. Description of the Related Art Conventionally, in a DC vacuum circuit breaker, as in other vacuum circuit breakers, a vacuum valve is supported by a frame mainly composed of an insulating material.

FIG. 4 is a perspective view showing an example of a conventional DC high-speed vacuum circuit breaker having a frame structure mainly composed of an insulator. Reference numeral 1 denotes a vacuum valve for interrupting a current, and its movable contact (not shown) is mechanically connected to an operating mechanism via an insulating rod 4 and an operating rod 5. The vacuum valves are fixed to metal vacuum valve mounting plates 12, 13. The vacuum valve mounting plates 12, 13 are fixed to an insulator frame 18, and the insulator frame 18 is fixed to the carriage 6. Conductors 10 and 11 for electrically connecting the circuit breaker and an external circuit are fixed to vacuum valve mounting plates 12 and 13. The insulator frame 18 provides insulation between the vacuum valve mounting plate 12 and the vacuum valve mounting plate 13 and insulation between the vacuum valve mounting plate 13 and the carriage 6. Furthermore, the insulator frame 18 has a structure surrounding the energized portions of the vacuum valve 1, the vacuum valve mounting plates 12 and 13, and the conductors 10 and 11, and insulates around the circuit breaker.

When a current flows through the circuit breaker, the conductor 10, the vacuum valve mounting plate 12, the vacuum valve 1, the vacuum valve mounting plate 1
3. Current flows through conductor 11 (or vice versa).
This current generates Joule heat in the vacuum valve 1. This heat is radiated from the terminals of the vacuum valve to the air through the energized portions of the vacuum valve mounting plates 12 and 13 and the conductors 10 and 11 connected to the terminals.

In the above-described frame structure mainly composed of an insulator, since the thermal conductivity of the insulator frame 18 is low, the heat radiation area of the Joule heat generated in the vacuum valve 1 when energized is mainly reduced by the vacuum valve. , And the heat cannot be sufficiently dissipated because it is limited only to the surface area of the terminals, the vacuum valve mounting plates 12 and 13 and the conductors 10 and 11 connected to the terminals. Further, the insulator frame 18 includes the vacuum valve 1 and the vacuum valve mounting plate 1.
Since it has a structure surrounding the energized portions of the conductors 2 and 13 and the conductors 10 and 11, the air circulation is hindered and the heat radiation effect is impaired. In addition, the conductor 1
A large amount of heat is generated due to the contact resistance between components 0 and 11.

Further, in the insulator frame structure as described above, since the insulator has a smaller longitudinal elastic modulus (Young's modulus) than metal, the insulator for contacting the contacts in the vacuum valve 1 with the circuit breaker turned on. Pressure (hereinafter referred to as contact pressure) increases the deflection of the insulator frame between the vacuum valve mounting plates 12 and 13 and between the vacuum valve mounting plate 13 and the carriage 6. When the breaking operation is performed, the time required for the contact to be separated is delayed by the amount by which the bending of the insulator frame generated in the breaker closed state returns to the original state, so that the breaking operation time becomes longer.

[0007]

As described above, the conventional DC high-speed vacuum circuit breaker having a frame structure mainly composed of an insulator has a small heat radiation area and efficiently radiates Joule heat generated by a vacuum valve. Since the current-carrying performance cannot be improved, the current-carrying capacity and the rated current cannot be increased. In addition, there is a problem that it takes a long time to perform the breaking operation because the insulating frame is bent by the contact pressure when the circuit breaker is turned on.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to increase the heat radiation area, efficiently radiate Joule heat generated in a vacuum valve, increase the rated current, and cut off the current. It is an object of the present invention to obtain a DC vacuum circuit breaker that can reduce the time.

[0009]

SUMMARY OF THE INVENTION A DC vacuum circuit breaker of the present invention has a fixed terminal and a movable terminal, a vacuum valve for interrupting current, and supports and fixes the fixed terminal, and surrounds the vacuum valve. It comprises a metal frame and a fixing base for supporting and fixing the metal frame via an insulating member.

Another DC vacuum circuit breaker of the present invention has a fixed-side terminal and a movable-side terminal, and is a vacuum valve for interrupting current, a first metal plate for supporting and fixing the fixed-side terminal, and (1) It is provided with a second metal plate for supporting and fixing the metal plate via a metal bar and an insulating member.

In the above, the conductor to be connected to the external circuit and the metal frame or metal plate are integrally formed.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing the configuration of the DC vacuum circuit breaker according to Embodiment 1 of the present invention.
This DC vacuum circuit breaker detects, for example, an abnormal current in a DC circuit at a DC electric railway substation and a feeder section, and among DC breakers that cut off this current, a DC valve using a vacuum valve in a current cutoff unit. Used for high-speed vacuum circuit breakers. In the figure, 1 is a fixed terminal 2 and a movable terminal 3
A movable contact and a fixed contact (not shown) that can be brought into contact with and separated from each other in an insulating cylinder whose both ends are sealed. Mechanically connected to an operating mechanism (not shown). 8
Is a first metal frame made of a metal plate surrounding and supporting the fixed side terminal 2 and surrounding the vacuum valve 1, and 9 is a second metal frame made of a metal plate connected to the movable side terminal 3 and surrounding the insulating rod 4. A frame 6 is a fixing base for supporting and fixing the first metal frame 8 via the insulating member 7 and the second metal frame 9, and in this case, is a carriage. The insulation between the first and second metal frames 8 and 9 and the insulation between the second metal frame 9 and the carriage 6 are provided by an insulating member 7.
A conductor 10 for electrically connecting the circuit breaker to an external circuit,
Numerals 11 are fixed to the first metal frame 8 and the second metal frame 9, respectively.

The Joule heat generated by the contacts in the vacuum valve 1 due to energization is transferred from the fixed terminal 2 and the movable terminal 3 of the vacuum valve 1 to the first metal frame 8, the second metal frame 9, the conductor 10, 11 and is released into the atmosphere from each surface. Since the heat radiation area of the first and second metal frames 8, 9 is large, the heat radiation is promoted as compared with the case of the prior art in which the insulator frame is adopted.
The temperature rise value of the energized portion is reduced. On the other hand, the upper limit of the temperature rise value is specified by a standard or the like, and if the upper limit value is the same as that of the prior art, the rated current can be increased.

Further, by fixing the vacuum valve 1 to the first metal frame 8, the first metal frame 8 and the second metal frame by the contact pressure applied to the contacts in the vacuum valve 1 with the circuit breaker turned on. Since the upward deflection of 9 is reduced as compared with the case of the insulator frame, the interruption time can be shortened.

In this embodiment, the vacuum valve is supported and fixed by a metal frame and is surrounded by the metal frame.
Since the heat dissipation area can be increased and the current-carrying performance can be improved, the current-carrying capacity and the rated current can be increased, and the bending time due to the contact pressure can be reduced, so that the cut-off time can be shortened.

Since the DC vacuum circuit breaker has a voltage specification of, for example, 1.5 kV, the insulation distance may be short, and there is no need to partition the ground with an insulating material. It can be. Further, it is used by being housed in a distribution board or the like, and a face plate is attached to the front side of the board.

Embodiment 2 FIG. FIG. 2 is a perspective view showing a configuration of a DC vacuum circuit breaker according to Embodiment 2 of the present invention. In the figure, reference numeral 22 denotes a first metal plate for supporting and fixing the fixed side terminal, and reference numeral 23 denotes the movable side terminal, and supports the first metal plate 22 via the metal column 14 made of a metal rod and the insulating member 7. The second metal plate to be fixed and the second metal plate 23 are supported and fixed to the carriage 6 via the metal pillar 15 and the insulating member 7.

In the first embodiment, the vacuum valve 1 has a closed structure surrounding the metal frame. In the second embodiment, the first and second metal plates 22 and 23 to which the vacuum valve 1 is fixed. Are supported by metal pillars 14 and 15 at the four corners. As in the first embodiment, the number of metal parts is increased and the heat dissipation area is increased, so that the current-carrying performance can be improved and the cutoff time can be shortened. Further, since the frame structure using the metal columns is used, a heat radiation effect due to air circulation inside and outside the frame structure is added, and the current-carrying performance is further improved. The current carrying capacity and the rated current can be further increased.

Embodiment 3 FIG. 3 is a perspective view showing a configuration of a DC vacuum circuit breaker according to Embodiment 3 of the present invention. In the figure, reference numeral 16 denotes a first metal plate with a conductor formed integrally with the first metal plate 22 and the conductor 10 in FIG. 2, and 17 denotes a first metal plate with a conductor formed by integrally forming the second metal plate 23 and the conductor 11 The second metal plate is made of a metal having high conductivity, such as aluminum or copper.

In the third embodiment, the conductors 10 and 11 connected to the external circuit in the second embodiment are formed integrally with the first and second metal plates 22 and 23, respectively. First and second metal plates 22,
Joule heat generated by the contact resistance between the electrodes 23 can be eliminated, and the temperature rise value of the energized portion can be reduced. The current-carrying performance is further improved, and the current-carrying capacity and the rated current can be increased.

Although the conductor connected to the external circuit is formed integrally with the first and second metal plates, the present invention is applied to the first embodiment, and the conductor is formed integrally with the metal frame. The same effect can be obtained.

[0022]

According to the DC vacuum circuit breaker of the present invention, a vacuum valve having a fixed-side terminal and a movable-side terminal for interrupting current, supporting and fixing the fixed-side terminal, and a metal valve surrounding the vacuum valve are provided. A frame and a fixing base for supporting and fixing the metal frame via an insulating member are provided. And the cutoff time can be shortened.

According to another DC vacuum circuit breaker of the present invention, there is provided a vacuum valve having a fixed-side terminal and a movable-side terminal to cut off current, a first metal plate for supporting and fixing the fixed-side terminal, and Since the first metal plate is provided with the second metal plate that supports and fixes the first metal plate via a metal rod and an insulating member, in addition to the above-described effects, the heat radiation effect can be further improved by air circulation, so Can be further improved.

Further, in the above, since the conductor to be connected to the external circuit and the metal frame or metal plate are integrally formed, heat generation due to contact resistance between the two is eliminated, and the current-carrying performance can be further improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration of a DC vacuum circuit breaker according to Embodiment 1 of the present invention.

FIG. 2 is a perspective view showing a configuration of a DC vacuum circuit breaker according to Embodiment 2 of the present invention.

FIG. 3 is a perspective view showing a configuration of a DC vacuum circuit breaker according to Embodiment 3 of the present invention.

FIG. 4 is a perspective view showing a configuration of a conventional DC vacuum circuit breaker.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vacuum valve 2 Fixed-side terminal 3 Movable-side terminal 6 Dolly of fixed stand 7 Insulation member 8 First metal frame 9 Second metal frame 10 Conductor 11 Conductor 14 Metal column 15 Metal column 16 First metal plate with conductor 17 Second metal plate with conductor 22 First metal plate 23 Second metal plate.

Claims (3)

[Claims] A vacuum valve having a fixed-side terminal and a movable-side terminal for interrupting current; a metal frame for supporting and fixing the fixed-side terminal and surrounding the vacuum valve; and an insulating member for connecting the metal frame to an insulating member. DC vacuum circuit breaker with a fixed base that is supported and fixed via 2. A vacuum valve having a fixed-side terminal and a movable-side terminal for interrupting current, a first metal plate for supporting and fixing the fixed-side terminal, and a metal rod and an insulating member for connecting the first metal plate to a metal rod. A DC vacuum circuit breaker having a second metal plate supported and fixed via a through hole. 3. The DC vacuum circuit breaker according to claim 1, wherein a conductor connected to an external circuit and a metal frame or a metal plate are integrally formed.