JP2020025409A - Disconnector - Google Patents

Abstract

To provide a disconnector capable of protecting a fuse for protecting a transformer, from an inrush current generated when a power is turned on.SOLUTION: The disconnector opens/closes an electric path between a first conductor 6 connected to a primary side of a transformer and a second conductor 7 disposed on the upstream side of the first conductor, and includes: a third conductor 51 that is pivotally supported in a turnable manner with respect to the first conductor in order to open/close the electric path between the first conductor and the second conductor; a fuse 52 that is interposed on an electric path of the third conductor; a resistor body 53; and a fourth conductor 54 that, when connecting the third conductor to the second conductor, connects the resistor body and the fuse in series by coming into contact with the second conductor before the third conductor, so as to cause the resistor body to be short-circuited as a result of succeeding contact between the third conductor and the second conductor.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a disconnector.

  To protect the transformer in the event of a transformer accident, a fuse is inserted in the electrical path between the primary side of the transformer and the power supply. For example, as a means for protecting the fuse from inrush current generated when power is turned on, an inrush current suppression resistor is connected to the primary side of the transformer, and when the power is turned on, the inrush current is suppressed by the inrush current suppression resistor. A technique is known in which a rush current suppression resistor is short-circuited at the start of a load operation in order to operate a transformer normally (for example, see Patent Document 1).

JP-A-58-179128

  However, in the case of Patent Literature 1, there is a problem that a relay circuit for short-circuiting the rush current suppression resistor and a relay control circuit for controlling the relay circuit must be mounted.

  Therefore, an object of the present invention is to provide a disconnector having a simple mechanical structure in order to protect a fuse from an inrush current generated when power is turned on.

  A main aspect of the present invention for solving the above-mentioned problem is a disconnection for opening and closing an electric circuit between a first conductor connected to a primary side of a transformer and a second conductor provided upstream of the first conductor. A third conductor rotatably supported on the first conductor for opening and closing an electric circuit between the first conductor and the second conductor; When connecting the fuse, the resistor, and the third conductor to the second conductor, the resistor is contacted with the second conductor prior to the third conductor to connect the resistor with the fuse. A fourth conductor that is connected in series, and then short-circuits the resistor by the third conductor contacting the second conductor.

  Other features of the present invention will become apparent from the accompanying drawings and the present specification.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to protect a fuse from the inrush current which generate | occur | produces at the time of turning on a power supply with a simple mechanical structure.

It is a block diagram showing an example of installation of a disconnector concerning this embodiment. It is a side view showing the state where the electric circuit was interrupted by the disconnector concerning this embodiment. It is a side view showing the state where the electric circuit was connected by the disconnector concerning this embodiment. It is a side view which shows the other state which connected the electric circuit by the disconnector which concerns on this embodiment.

  At least the following matters will be made clear by the description in the present specification and the accompanying drawings.

=== Example of disconnector installation ===
FIG. 1 is a block diagram illustrating an installation example of the disconnector according to the present embodiment. In FIG. 1, only the transformer 1, the rectifier circuit 2, the smoothing capacitor 3, the load 4, and the disconnector 5 are taken for simplicity.

  The transformer 1 has a primary winding 1A and a secondary winding 1B, and from the upstream transmission and distribution line to the primary winding 1A according to a winding ratio of the primary winding 1A and the secondary winding 1B. This is a voltage converter that reduces the supplied AC voltage and outputs the reduced AC voltage from the secondary winding 1B.

  The rectifier circuit 2 is a circuit that performs, for example, full-wave rectification on the AC voltage output from the secondary winding 1B of the transformer 1.

  The smoothing capacitor 3 is an element that smoothes the voltage after full-wave rectification output from the rectifier circuit 2 so that the load 4 at the subsequent stage operates.

  The disconnector 5 is a device that cuts off an electric circuit between the transformer 1 and a transmission and distribution line upstream of the transformer 1. For this purpose, the disconnector 5 is inserted in an electric circuit between the first conductor 6 connected to the primary winding 1A and the second conductor 7 provided upstream of the first conductor 6. . Although the disconnector 5 includes a fuse for protecting the transformer 1, there is a possibility that the fuse is blown by an inrush current generated when an electric circuit between the first conductor 6 and the second conductor 7 is closed. . Then, in order to solve this problem, when the disconnector 5 closes the electric circuit between the first conductor 6 and the second conductor 7, the disconnector 5 connects the resistor in series with the fuse, and then short-circuits the resistor. It has a mechanical structure that realizes this. Details of the disconnector 5 will be described later.

=== Configuration of disconnector ===
FIG. 2 is a side view showing a state where an electric circuit is cut off by the disconnector according to the present embodiment. FIG. 3 is a side view showing one state where the electric circuit is connected by the disconnector according to the present embodiment. FIG. 4 is a side view showing another state in which the electric circuit is connected by the disconnector according to the present embodiment.

  The disconnector 5 includes a third conductor 51, a fuse 52, a resistor 53, a fourth conductor 54, and a spring 55.

  The third conductor 51 is a conductor that is rotatably supported on the first conductor 6 to connect or cut off an electric path between the first conductor 6 and the second conductor 7. For example, when the third conductor 51 rotates clockwise around the support shaft S1, the disconnector 5 cuts off the electric path between the first conductor 6 and the second conductor 7, while the third conductor 51 is supported. When turning around the axis S1 in the counterclockwise direction, the disconnector 5 connects the electric path between the first conductor 6 and the second conductor 7. The third conductor 51 includes a fifth conductor 51A and a sixth conductor 51B, and the fifth conductor 51A and the sixth conductor 51B are connected via a fuse 52. The fifth conductor 51A is a conductor closer to the first conductor 6 than the fuse 52, and is connected to the first conductor 6 via the support shaft S1. The sixth conductor 51B is a conductor closer to the second conductor 7 than the fuse 52, and connects or cuts off an electric path between the sixth conductor 51B and the second conductor 7 as the fifth conductor 51A rotates. For example, the tip of each of the sixth conductor 51B and the second conductor 7 has a shape on the side where the knife switch is inserted and on the side where the knife switch is inserted. When the sixth conductor 51B is inserted into the second conductor 7, the sixth conductor 51B becomes the second conductor 51B. The state of connection with the two conductors 7 is maintained. For example, by operating an insulating lever (not shown) coupled to the fifth conductor 51A or the sixth conductor 51B, the fifth conductor 51A is rotated, and the sixth conductor 51B is electrically connected to the second conductor 7. Connect or disconnect.

  The resistor 53 is an element that is connected in series with the fuse 52 or short-circuited according to the operation of the third conductor 51 and the fourth conductor 54.

  The fourth conductor 54 connects the resistor 53 in series with the fuse 52 by contacting the second conductor 7 before the third conductor 51 when connecting the third conductor 51 to the second conductor 7. Thereafter, the third conductor 51 contacts the second conductor 7 to short-circuit the resistor 53. The fourth conductor 54 includes a seventh conductor 54A and an eighth conductor 54B. The seventh conductor 54A is connected to the sixth conductor 51B via the support shaft S2, and is rotatably supported on the sixth conductor 51B. The seventh conductor 54A rotates around the support shaft S2 on the opposite side of the sixth conductor 51B from the second conductor 7. The eighth conductor 54B includes a ninth conductor 54C and a tenth conductor 54D, and the ninth conductor 54C and the tenth conductor 54D are connected via a resistor 53. The ninth conductor 54C is a conductor closer to the seventh conductor 54A than the resistor 53, is connected to the seventh conductor 54A via the support shaft S3, and is rotatable with respect to the seventh conductor 54A. Supported. The tenth conductor 54 </ b> D is a conductor closer to the second conductor 7 than the resistor 53, and protrudes toward the second conductor 7 from a hole 51 </ b> C formed in the sixth conductor 51 </ b> B. It is slidably inserted. The outer peripheral surface of the tenth conductor 54D is insulated from the inner peripheral surface of the hole 51C. For example, a member made of an insulating material may be attached to the outer peripheral surface of the tenth conductor 54D or the inner peripheral surface of the hole 51C. The resistor 53 is provided on the opposite side of the sixth conductor 51B from the side where the tenth conductor 54D protrudes.

  When the sixth conductor 51B is not in contact with the second conductor 7, the spring body 55 causes the sixth conductor 51B and the seventh conductor 51D to project from the hole 51C in the direction of the second conductor 7. It is a coil spring that elastically urges between the conductor 54A.

=== Disconnector connection operation ===
First, in order to connect an electric path between the first conductor 6 and the second conductor 7, an operator operates the insulating lever in a direction approaching the second conductor 7.

  With the operation of the insulating lever, the fifth conductor 51A rotates counterclockwise around the support shaft S1, and the sixth conductor 51B approaches the second conductor 7.

  The tenth conductor 54D protrudes from the hole 51C of the sixth conductor 51B by the elastic force of the spring body 55. Therefore, when the sixth conductor 51B approaches the second conductor 7, the tenth conductor 54D contacts the second conductor 7 before the sixth conductor 51B contacts the second conductor 7. By this contact, the resistor 53 is connected in series with the fuse 52 in the electric path between the first conductor 6 and the second conductor 7. Therefore, it is possible to protect the fuse 52 from an inrush current. Thereafter, the sixth conductor 51B comes into contact with the second conductor 7 against the elastic force of the spring body 53. Due to this contact, the resistor 53 is short-circuited in the electric path between the first conductor 6 and the second conductor 7. Therefore, since current flows only through the fuse 52, the transformer 1 can operate normally. The second conductor 7 and the sixth conductor 51B maintain the connected state by fitting the shapes of the knife switch insertion side and the insertion side.

=== Disconnecting switch disconnection operation ===
First, in order to cut off the electric path between the first conductor 6 and the second conductor 7, the operator operates the insulating lever in a direction away from the second conductor 7.

  With the operation of the insulating lever, the fifth conductor 51A rotates clockwise around the support shaft S1, and the sixth conductor 51B moves away from the second conductor 7. At the same time, the tenth conductor 54D projects from the hole 51C of the sixth conductor 51B by the elastic force of the spring body 55.

=== Summary ===
As described above, the disconnector 5 according to the present embodiment includes the first conductor 6 connected to the primary side of the transformer 1, the second conductor 7 provided upstream of the first conductor 6, A third conductor 51 rotatably supported by the first conductor 6 to open and close an electric circuit between the first conductor 6, a fuse 52 interposed in the electric circuit of the third conductor 51, a resistor 53, When the third conductor 51 is connected to the second conductor 7, the resistor 53 is connected in series with the fuse 52 by contacting the second conductor 7 before the third conductor 51. And a fourth conductor 54 that short-circuits the resistor 53 by contacting the second conductor 7.

  In the present embodiment, the third conductor 51 includes a fifth conductor 51A closer to the first conductor 6 than the fuse 52 and a sixth conductor 51B closer to the second conductor 7 than the fuse 52. One end of the fourth conductor 54 is rotatably supported on the sixth conductor 51B, and the other end of the fourth conductor 54 is connected to the hole 51C formed in the sixth conductor 51B. The resistor 53 is interposed slidably in the direction of the second conductor 7 while being insulated from 51B, and the resistor 53 is interposed in the electric path of the fourth conductor 54.

  In the present embodiment, an insulator made of a rubber member, a resin member, or the like is provided on the outer peripheral surface at the other end of the fourth conductor 54 or the inner peripheral surface of the hole 51C.

  In the present embodiment, the third conductor 51 is composed of a fifth conductor 51B closer to the first conductor 6 than the fuse 52 and a sixth conductor 51B closer to the second conductor 7 than the fuse 52. The fourth conductor 54 is rotatably supported on the sixth conductor 51A, and is rotatably supported on the seventh conductor 54A. The fourth conductor 54 is formed on the sixth conductor 51B. An eighth conductor 54B is slidably inserted in the direction of the second conductor 7 in a state of being insulated from the sixth conductor 51B with respect to the hole 51C to be formed. It is interposed in the electric path of the conductor 54A or the eighth conductor 54B.

  In the present embodiment, an insulator made of a rubber member, a resin member, or the like is provided on the outer peripheral surface of the eighth conductor 54B or the inner peripheral surface of the hole 51C.

  Further, in the present embodiment, when the third conductor 51 is not connected to the second conductor 7, the sixth conductor 51B and the sixth conductor 51B are so arranged that the eighth conductor 54B projects in the direction of the second conductor 7 via the hole 51C. There is further provided a spring body 55 for elastically urging between the seventh conductors 54A.

  In the present embodiment, the resistor 53 is a coil spring that is interposed in the electric path of the eighth conductor 54B and elastically urges the sixth conductor 51B and the seventh conductor 54A toward each other.

  According to the present embodiment, by providing a simple mechanical structure, it is possible to protect the fuse 52 from an inrush current generated when the power is turned on. Further, the life of the fuse 52 can be extended. Further, the capacity of the fuse 52 can be set small, and the current of the transformer 1 immediately after the occurrence of an accident can be reliably cut off.

  It should be noted that the above embodiments are intended to facilitate understanding of the present invention, and are not intended to limit the present invention. The present invention can be modified and improved without departing from the spirit thereof, and the present invention also includes equivalents thereof.

REFERENCE SIGNS LIST 1 transformer 2 rectifier circuit 3 smoothing capacitor 4 load 5 disconnector 6 first conductor 7 second conductor 51 third conductor 51A fifth conductor 51B sixth conductor 52 fuse 53 resistor 54 fourth conductor 54A seventh conductor 54B eighth Conductor 54C Ninth conductor 54D Tenth conductor 55 Spring bodies S1, S2, S3 Support shaft

Claims (7)

A disconnector for opening and closing an electric circuit between a first conductor connected to a primary side of a transformer and a second conductor provided upstream of the first conductor,
A third conductor rotatably supported on the first conductor to open and close an electric circuit between the first conductor and the second conductor;
A fuse interposed in an electric path of the third conductor;
A resistor and
When connecting the third conductor with the second conductor, the resistor is connected in series with the fuse by contacting the second conductor prior to the third conductor, and then the third conductor A fourth conductor that short-circuits the resistor by contacting the second conductor;
A disconnector characterized by comprising: The third conductor includes a fifth conductor closer to the first conductor than the fuse, and a sixth conductor closer to the second conductor than the fuse,
One end of the fourth conductor is rotatably supported on the sixth conductor,
The other end of the fourth conductor is slidably inserted in the direction of the second conductor in a state of being insulated from the sixth conductor with respect to a hole formed in the sixth conductor,
The disconnector according to claim 1, wherein the resistor is interposed in an electric path of the fourth conductor. The disconnector according to claim 2, further comprising an insulator provided on an outer peripheral surface of the other end of the fourth conductor or an inner peripheral surface of the hole. The third conductor includes a fifth conductor closer to the first conductor than the fuse, and a sixth conductor closer to the second conductor than the fuse,
A fourth conductor rotatably supported by the sixth conductor and a hole rotatably supported by the seventh conductor and formed in the sixth conductor; And an eighth conductor that is slidably inserted toward the direction of the second conductor in an insulated state.
The disconnector according to claim 1, wherein the resistor is interposed in an electric path of the seventh conductor or the eighth conductor. The disconnector according to claim 4, further comprising an insulator provided on an outer peripheral surface of the eighth conductor or an inner peripheral surface of the hole. When the third conductor is not connected to the second conductor, the gap between the sixth conductor and the seventh conductor is set such that the eighth conductor projects in the direction of the second conductor through the hole. The disconnector according to claim 4, further comprising a spring body that elastically biases. The resistor is interposed in an electric path of the eighth conductor,
The disconnector according to claim 6, wherein the disconnector is a coil spring that elastically urges the sixth conductor and the seventh conductor to approach each other.

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