JP2005304190A - Dc breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a structure and an arrangement of a disconnector so as to improve assembling property and reduce a space in a discharging disconnector of a commutating capacitor mounted on the back face side of a cradle equipped with a drawing circuit breaker in a DC breaker for blocking by using the commutating capacitor. <P>SOLUTION: In the DC breaker provided with a plurality of discharging circuit breakers 4 in parallel for connecting the capacitor to a discharging circuit behind the cradle 1 equipped with the drawing circuit breaker as a means for discharging a charge stored in the commutating capacitor to the ground through a discharging resistor, all the discharging circuit breakers 4 are vertically turned off and aligned horizontally and vertically oriented, fixed contacts 4a are provided on the upper back face side of the cradle in parallel, opening and closing levers 4b are coupled on a lateral common rotational shaft 9 at an lower end, an operation handle is linked to the rotational shaft, and the disconnectors are collectively opened and closed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a DC circuit breaker that cuts off a main circuit current by combining a commutation capacitor with a draw-out type circuit breaker (for example, a high-pressure vacuum circuit breaker) housed in a switchboard such as a power center. This relates to the structure of the disconnecting switch for discharging the commutation capacitor disposed in the cradle in the board on which the power is mounted.

As a direct current circuit breaker, a commutation capacitor is combined between the main circuit contacts of the circuit breaker, and the current charged in the commutation capacitor in advance when the main circuit current (DC) is interrupted is superimposed on the main circuit current. An interruption method is known in which the arc generated between the contacts is extinguished to interrupt the main circuit current when the combined current becomes zero. In addition, as a safety measure at the time of maintenance and inspection of the circuit breaker, as a means for discharging the electric charge charged in the commutation capacitor to the ground side through a discharge resistor, with respect to the DC breaker adopting such a breaker method, A configuration is known in which a disconnecting switch for discharging a commutation capacitor is provided behind a cradle installed in a panel with a drawer type circuit breaker (see, for example, Patent Document 1).
FIG. 4 is a configuration and layout diagram of the discharge disconnector disclosed in Patent Document 1 (FIGS. 1, 2 and 9). In FIG. 4, reference numeral 1 denotes a cradle which is mounted in a panel with a draw-out type circuit breaker (not shown) (for example, a high-pressure vacuum circuit breaker), and 2 is a breaker of the circuit breaker penetrating the back plate of the cradle 1. Bushing-type disconnection part arranged so as to be connected to 3, 3 is a support seat (insulating plate) of a grounding terminal arranged on the back plate of the cradle side by side at the same height as the bushing-type disconnection part 2, 4 is the bushing-type disconnection The terminal 2a of the part 2 and the grounding terminal 3a fixed to the support seat 3 and the discharge disconnector provided behind the cradle 1 corresponding to the grounding terminal 3a and 4a are the terminal plate 2a of the bushing-type disconnecting part 2 and the grounding Fixed contact 4 attached to the terminal 3a, 4b is an open / close lever attached to the tip of the insulating lever 4c with a disconnecting blade 4d facing the fixed contact 4a, 5 is a discharge resistance, 6 is a discharge disconnector 4 arranged side by side. Each open A connecting link 8 connecting the levers 4 is a rotary operating shaft connected to the open / close lever 4b of the discharge disconnector 4 arranged at the left end. The operating shaft 8 passes through the bottom surface of the cradle 1 to the front side in the panel. It is connected to a manual operation handle (not shown).

The operation of the discharge disconnector configured as described above is described in detail in Patent Document 1, and in order to discharge the electric charge charged in the commutation capacitor to the ground side through the discharge resistor 5 when the circuit breaker is inspected, By manually operating the handle, the operating shaft 8 is turned clockwise toward the OFF position. As a result, the open / close lever 4b of each discharging disconnector 4 interconnected via the connecting links 6 and 7 rotates counterclockwise from the disconnecting position in FIG. 4A, and the disconnecting blade 4d becomes a fixed contact. 4a is contacted, the discharge disconnector is closed, and the charge of the commutation capacitor is discharged to the ground side through the discharge resistor.
Japanese Patent Laid-Open No. 2001-195961

Incidentally, the discharge disconnector having the conventional configuration described in FIG. 4 has the following problems in terms of structure and assemblability.
That is, in the conventional configuration of FIG. 4, the three discharge disconnectors 4 arranged side by side on the left and right behind the cradle 1 are horizontal disconnectors, and the lower end of the open / close lever 4b of each disconnector is used as the mounting base. On the other hand, after the shafts are separately supported, the open / close levers 4b are connected to each other by connecting links 6 and 7, and the three disconnectors are collectively opened and closed by a handle operation. Also, within the limited width range of the cradle 1, in order to ensure the required insulation distance between the conductors of adjacent disconnectors, the disconnectors aligned at the left and right ends and the disconnector aligned in the center are positioned in the front-rear direction. Are moved apart.
For this reason, the assembly structure of the discharge disconnector disposed on the back surface of the cradle 1 becomes complicated, and the number of parts including the connecting links 6 and 7 increases. Moreover, high assembly accuracy is required to align the disconnecting blade 4d of each disconnector 4 with the fixed contact 4a so as to ensure the same contact amount during the closing operation of the discharge disconnector. When assembling the product, it takes a lot of time and labor to adjust the mounting position of each part and the fulcrum position of the opening / closing lever. In addition, in order to ensure the necessary insulation distance between adjacent disconnectors, the disconnectors aligned at both the left and right ends and the disconnector aligned in the center are shifted in the front-rear direction, so the cradle depth direction Therefore, there is a problem that the space occupied by the disconnecting switch is increased and the switchboard is enlarged.

  The present invention has been made in view of the above points, and has improved the structure and arrangement of the disconnecting switch for the discharge of the commutation capacitor so as to solve the above problems and improve the assembling property and save space in the panel. An object of the present invention is to provide a direct current circuit breaker.

In order to achieve the above object, according to the present invention, a DC circuit breaker that cuts off a main circuit current by combining a circuit breaker with a commutation capacitor, the charge of the commutation capacitor is grounded through a discharge resistor As a means for discharging, in the rear of the cradle equipped with a drawer type circuit breaker, a plurality of discharge disconnectors for connecting the commutation circuit including the capacitor to the discharge circuit are arranged in parallel,
The discharge disconnectors are arranged vertically in a vertical cut and arranged side by side in the vertical direction, and the open / close levers of each disconnector are connected to a common rotating shaft, and an operation handle is connected to the rotating shaft. The disconnectors are collectively opened and closed (Claim 1), and the discharge disconnector is configured as follows as a specific mode.
(1) The discharge disconnector has a structure in which a stationary contact and an open / close lever provided with a disconnecting blade at the end of an insulating lever are paired, and the fixed contact of each disconnector is juxtaposed on the upper back side of the cradle. The open / close levers are arranged in the vertical direction in accordance with the arrangement of the stationary contacts, and the lower ends of the open / close levers are connected to the common horizontal rotation shaft (Claim 2).
(2) In the preceding paragraph (1), the fixed contact of the discharge disconnector is provided at a position protruding rearward from the rear surface of the cradle, and the opening position of the opening / closing lever is located closer to the rear surface of the cradle based on this position. Set and open / close operation (claim 3).

According to the above configuration, since the open / close levers of the discharge disconnectors arranged in the left and right rows in the back of the cradle are connected together on the axis of the common rotating shaft, Compared to the conventional assembly structure (see Fig. 4) that is connected to each other via a connecting link, the number of parts is reduced, and it is necessary to adjust the rotation fulcrum position of the open / close lever for each disconnector during assembly. As a result, the assembly workability of the product can be greatly improved.
Moreover, by switching the disconnect switch from the conventional horizontal cut to the vertical cut, the open / close levers are arranged vertically, so that even when the disconnect switches are arranged in a row on the left and right sides, they are sufficient between the disconnect switches. Insulation distance can be secured, and in addition, the opening position of the opening / closing lever is set in front of the fixed contact (cradle side), so that the space in the panel can be saved compared to the conventional structure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on the examples shown in FIGS. In addition, in the figure of an Example, the same code | symbol is attached | subjected to the member corresponding to FIG. 4, and the description is abbreviate | omitted.
FIGS. 1A and 1B are block diagrams of an embodiment of the present invention corresponding to the conventional example of FIG. 4. Three discharge disconnectors 4 arranged behind the cradle 1 side by side are vertically cut. The disconnecting contactor 4a is formed so as to protrude rearward in an L shape from the terminal 2a of the bushing-type disconnecting portion 2 and the grounding terminal 2a of the terminal support seat 3.
On the other hand, as shown in FIGS. 2 (a) and 2 (b), the open / close lever 4b of each disconnector 4 has a disconnecting blade 4d consisting of two blades at the tip of an insulating lever 4c via a bolt 4e and a contact spring 4f. As shown in FIG. 1, in accordance with the arrangement of the stationary contacts 4a, it is arranged in a vertical orientation at a position immediately below it, and the lower ends of the open / close levers 4b are laid on the bottom plate of the cradle 1 at this position. The horizontal common rotation shaft 9 is coupled and connected in the same direction on the axis. In addition, 9a is a support (bearing metal fitting) arranged at both ends of the common rotating shaft 9. Further, an operating lever 9b extending forward perpendicular to the axis is fixedly coupled on the axis of the rotary shaft 9, and the operating lever 9b is laid on the bottom side of the cradle as shown in FIG. It is connected to a lever-type manual operation handle 11 arranged forward via a connecting rod 10.

In the above configuration, as shown in FIG. 1B, the open / close lever 4b of the discharge disconnector 4 is normally held in a posture in which it is separated from the fixed contact 4a and tilted toward the back of the cradle 1 (disconnection). Device OFF). In this open state, a required insulation distance A is secured between the disconnectors 4 arranged in a line on the left and right. Further, since the opening / closing lever 4b is retracted toward the empty space remaining below the bushing-type disconnecting portion 2, it is not necessary to secure an extra space in the panel.
When the operation handle 11 is pushed from the OFF position in FIG. 3A to the ON position in FIG. 3B in order to discharge the electric charge charged in the commutation capacitor to the ground side from the OFF state, the connecting rod 10 , The open / close lever 4b of each disconnector connected to the rotary shaft via the operation lever 9b and the rotary shaft 9 rotate clockwise together, and the disconnecting blade 4d contacts the fixed contact 4a to disconnect the disconnector. 4 is inserted. Thereby, the charge of the commutation capacitor is discharged to the ground side through the discharge resistor.

  In the illustrated embodiment, three discharge disconnectors 4 are provided behind the cradle 1 corresponding to the commutation and discharge circuit of FIG. 9 in Patent Document 1, but FIG. Of course, even if two discharge disconnectors 4 are provided corresponding to the commutation and discharge circuits, the same configuration and arrangement of the discharge disconnectors as in the illustrated embodiment can be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a structural layout diagram of a discharge disconnector equipped in a DC interrupter according to an embodiment of the present invention, wherein (a) and (b) are a rear view and a side view, respectively. FIG. 2 is a structural diagram of an open / close lever of the discharge disconnector in FIG. 1, wherein (a) and (b) are a front view and a top view, respectively. It is explanatory drawing of the opening / closing operation | movement of the disconnector for discharge in FIG. 1, (a), (b) is a figure showing the state of OFF and ON, respectively. FIG. 2 is a structural layout diagram of a discharge disconnector in a conventional DC interrupter, wherein (a) and (b) are a rear view and a side view, respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cradle 4 Discharge disconnector 4a Fixed contact 4b Opening / closing lever 4c Insulation lever 4d Disconnecting blade 9 Common rotating shaft 10 Connecting rod 11 Operation handle

Claims (3)

A DC circuit breaker that combines a circuit breaker and a commutation capacitor to cut off the main circuit current. As a means for discharging the charge of the commutation capacitor to the ground side through a discharge resistor, a drawer type circuit breaker is used. In the rear of the mounted cradle, a plurality of discharge disconnectors that connect the commutation circuit including the capacitor to the discharge circuit are juxtaposed,
The discharge disconnectors are arranged vertically in a vertical cut and arranged side by side in the vertical direction, and the open / close levers of each disconnector are connected to a common rotating shaft, and an operation handle is connected to the rotating shaft. A DC circuit breaker characterized in that the disconnector is collectively opened and closed. 2. The DC circuit breaker according to claim 1, wherein the discharge disconnecting device is a pair of a fixed contact and an opening / closing lever having a disconnecting blade at the tip of the insulating lever, and the fixed contact of each disconnecting device is connected to the upper rear side of the cradle. The DC breaker is characterized in that the open / close levers are juxtaposed in the vertical direction according to the arrangement of the stationary contacts, and the lower ends of the open / close levers are connected to a common horizontal rotation shaft. 3. The DC circuit breaker according to claim 2, wherein the fixed contact of the discharge disconnecting switch is provided at a position protruding rearward from the rear surface of the cradle, and the opening position of the opening / closing lever is determined based on the position. A DC circuit breaker characterized in that it is set close to be opened and closed.

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