JP5019322B2 - Shunt type superconducting fault current limiter - Google Patents

Description

  The present invention relates to a shunt-type superconducting current limiter that suppresses an excessive current such as a short-circuit current flowing in an electric circuit.

  2. Description of the Related Art Conventionally, there is known a shunt-type superconducting current limiter in which a superconducting element and a commutation switch are connected in series, and a current-limiting fixed coil is connected in parallel thereto.

  In such a shunt type superconducting fault current limiter, during normal energization, the superconducting element is in a superconducting state and the current limiting fixed coil is short-circuited, and current flows through the superconducting element through the electric circuit. If an excessive current flows in the circuit due to a short circuit accident, etc., the superconducting element switches from the superconducting state to the non-superconducting state (high resistance state), so that the current is commutated to the fixed coil for current limiting, and the shunt type superconducting current limiter has high impedance. State, and excessive current flowing in the electric circuit is suppressed. At this time, the commutation switch is driven to cut off the current flowing in the superconducting element, thereby reducing the energy consumption of the superconducting element.

  Usually, in a shunt type superconducting fault current limiter, it is necessary to use a special switch that is driven at high speed as a commutation switch. When a general high-speed circuit breaker is used as a commutation switch, the breaker of this high-speed breaker is disposed above for insulation between the grounds, and the drive unit that operates the breaker is disposed on the ground side. Since the blocking unit and the driving unit are thus separated from each other, it is difficult to operate the blocking unit at a high speed, and even if the blocking unit can be operated at a high speed, it requires a large amount of energy to drive. The part becomes larger and the cost also increases.

Therefore, there is a shunt-type superconducting fault current limiter that opens the commutation switch using the electromagnetic repulsive force generated by the magnetic field generated when the superconducting element is switched from the superconducting state to the non-superconducting state and the current flows to the current limiting fixed coil It has been proposed (see, for example, Patent Document 1). This shunt type superconducting fault current limiter does not require an operating mechanism or an external power source for opening the commutation switch, and can operate at high speed.
JP 2005-50737 A

  However, the shunt type superconducting current limiter disclosed in Patent Document 1 is provided with a mechanism for maintaining the open state after the commutation switch is opened. However, the commutation switch is closed (reclosed). It was not possible to automatically perform the input operation for the purpose.

  The present invention has been made in view of the above, and an object of the present invention is to provide a shunt superconducting current limiter capable of automatically opening and closing a commutation switch without requiring an external power source.

  In order to achieve the above object, a shunt-type superconducting fault current limiter of the present invention is a series circuit in which a superconducting element and a current interrupter having a stationary contact and a movable contact facing the stationary contact are connected in series. A current-clamping fixed coil connected in parallel to the series circuit, and connected to the movable contact and opposed to one end surface of the current-limiting fixed coil, the current-limiting fixed coil An electromagnetic repulsion plate that opens the current breaker by moving the movable contact in a direction away from the fixed contact by an electromagnetic repulsion force generated between the current-limiting stationary coil and the current-limiting stationary coil. A bottom wall having an insulating plate coupled to the electromagnetic repulsion plate, an exhaust port provided with a vent and a check valve, a cylindrical side wall erected on one surface of the bottom wall, and the movable Connected to contact and reciprocates in the side wall A lid that is movably provided, and an elastic body that stands on the bottom wall and supports the insulating plate outside the side wall on the one surface side of the bottom wall, and the electromagnetic repulsive force causes the When the movable contact moves together with the electromagnetic repulsion plate in a direction away from the fixed contact, the bottom wall, the side wall, and the lid are surrounded by the lid that moves in conjunction with the movable contact. The air inside the air chamber is pushed out through the exhaust port and the vent hole, and the elastic body is compressed and stored by the insulating plate that moves in conjunction with the electromagnetic repulsion plate. The movable contact is fixedly contacted while restraining the moving speed of the lid and the movable contact connected thereto by taking air from outside into the air chamber through the vent hole. It is moved in a direction approaching to anda dosing means for closing the current circuit breaker.

  The shunt superconducting fault current limiter of the present invention includes a superconducting element and a parallel circuit in which a plurality of current breakers each having a fixed contact and a movable contact facing the fixed contact are connected in parallel to each other. A first circuit connected in series and a plurality of cylindrical current limiting fixed coils corresponding to the plurality of current breakers are connected in series to each other, and a second circuit connected in parallel to the first circuit A circuit, and each movable contactor of each of the current breakers is connected to one end face of each of the current limiting fixed coils, and each of the current limiting fixed coils is energized. The electromagnetic contacts that open the current breakers by moving the movable contacts in a direction away from the corresponding fixed contacts of the current breakers by the electromagnetic repulsive force generated between the current limiting fixed coils. A repulsion plate and the electromagnetic repulsion A bottom wall having an insulating plate coupled to the plate, a vent and an exhaust port provided with a check valve; a cylindrical side wall erected on one surface of the bottom wall; and each movable contact A lid body that is connected to the side wall so as to be reciprocally slidable, and an elastic body that stands on the bottom wall outside the side wall on the one surface side of the bottom wall and supports the insulating plate; The lid body that moves in conjunction with each movable contact when the movable contact moves together with the electromagnetic repulsion plate in a direction away from the corresponding fixed contact. The air in the air chamber surrounded by the bottom wall, the side wall, and the lid is pushed out to the outside through the exhaust port and the vent, and the elastic plate is moved by the insulating plate that moves in conjunction with the electromagnetic repulsion plate. After compressing and storing the body, the elastic body is released and stretched In addition, by taking air from the outside into the air chamber through the vent, the fixed contacts corresponding to the movable contacts are controlled while suppressing the moving speed of the lid and the movable contacts connected thereto. And a closing means for closing each of the current breakers by moving in a direction approaching the child.

  According to the shunt-type superconducting current limiting device of the present invention, the commutation switch can be automatically opened and turned on without requiring an external power source.

  The best mode for carrying out the present invention will be described below with reference to the drawings. In the following description of the drawings, the same or equivalent parts are denoted by the same or equivalent reference numerals. However, it should be noted that the drawings are schematic and different from the actual ones. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  Further, the embodiment described below exemplifies an apparatus and a method for embodying the technical idea of the present invention. The technical idea of the present invention is the arrangement of each component as described below. It is not something specific. The technical idea of the present invention can be variously modified within the scope of the claims.

(First embodiment)
FIG. 1 is a connection diagram electrically showing a shunt type superconducting fault current limiter according to the first embodiment of the present invention, and FIG. 2 is a current cutoff of the shunt type superconducting fault current limiter according to the first embodiment. FIG. 3 is a diagram for explaining the operation of the current breaker and closing unit shown in FIG. 2 when the opening is opened, and FIG. 4 is a diagram illustrating the current breaking unit and closing unit shown in FIG. It is a figure for demonstrating the operation | movement at the time of injection | throwing-in.

  As shown in FIG. 1, the shunt superconducting fault current limiter according to the first embodiment is provided in the middle of the electric circuit 1, and a superconducting element 2 and a current breaker 3 are connected in series. It has an electrical configuration in which a current-limiting fixed coil 4 is connected in parallel to a series circuit with the current breaker 3.

  The superconducting element 2 is made of a known superconductor that is in a superconducting state during normal energization and flows a current, and changes from a superconducting state to a non-superconducting state (high resistance state) when an overcurrent flows in the electric circuit 1 due to a short circuit accident or the like. .

  The current breaker 3 includes a known vacuum valve or the like as shown in FIG. 2 and functions as a commutation switch for a shunt type superconducting current limiter.

  The current breaker 3 has a breaker chamber 5. The shut-off chamber 5 is vacuum-tightly configured by a cylindrical insulating container 6 made of an insulator and metal lids 7 and 8 provided at both ends of the insulating container 6. A fixed conductive rod 10 having a fixed contact 9 fixed to the end is fixed to the lid 7. A movable conductive rod 12 having a movable contact 11 that is detachable from the fixed contact 9 is fixed to the end of the lid 8 so as to be movable in the axial direction. As shown in FIG. 1, the fixed conductive rod 10 is connected to one end of the superconducting element 2, and the movable conductive rod 12 is connected to the electric circuit 1.

  A bellows 13 is attached to the movable conductive rod 12, and the movable conductive rod 12 can be moved in the axial direction while keeping the inside of the blocking chamber 5 in a vacuum-tight state. A metal arc shield 14 is provided on the top of the bellows 13 to prevent the bellows 13 from being covered with arc vapor. Further, a metal arc shield 15 is provided in the shut-off chamber 5 so as to cover the fixed contact 9 and the movable contact 11, thereby preventing the insulating container 6 from being covered with arc vapor.

  One end of a movable rod 16 made of an insulator is connected to the end of the movable conductive rod 12 opposite to the side on which the movable contact 11 is fixed. An electromagnetic repulsion plate 17 made of a conductor such as aluminum is fixed to the movable rod 16 so that the movable rod 16 penetrates the approximate center thereof.

  As shown in FIG. 2, a closing portion 20 is connected to the current breaker 3 via a movable rod 16 and an electromagnetic repulsion plate 17.

  The insertion portion 20 is connected to the bottom wall 21, a cylindrical side wall 22 erected on the top surface of the bottom wall 21, and the other end of the movable rod 16, and is provided in the side wall 22 so as to be slidable back and forth. A lid 23, an annular insulating plate 24 fixed to the lower surface of the electromagnetic repulsion plate 17, and an elastic body that stands on the bottom wall 21 and supports the insulating plate 24 outside the side wall 22 of the upper surface of the bottom wall 21. And a plurality of springs 25. The inner peripheral surface of the side wall 22 and the outer peripheral surface of the lid body 23 are sealed by a seal ring or the like (not shown).

  The bottom wall 21 is provided with a vent 26 and an exhaust 27. A check valve 28 is provided at the exhaust port 27. The check valve 28 includes a valve body 29, a valve body 30 that opens and closes the exhaust port 27, and a spring 31 that supports the valve body 30, and is surrounded by the bottom wall 21, the side wall 22, and the lid body 23 from the outside. The air flow toward the air chamber 32 is stopped. The flow from the air chamber 32 toward the outside flows without being stopped.

  Between the current breaker 3 and the electromagnetic repulsion plate 17, a current-limiting fixed coil 4 formed in a cylindrical shape has one end surface facing the electromagnetic repulsion plate 17, and the central opening portion of the movable conductive rod 12. And the movable rod 16 is arrange | positioned so that it may penetrate. As shown in FIG. 1, one end of the current limiting fixed coil 4 is connected to the other end of the superconducting element 2, and the other end of the current limiting fixed coil 4 is connected to the movable conductive rod 12.

  Next, the operation of the shunt superconducting fault current limiter according to the first embodiment will be described.

  During normal energization, the movable conductive rod 12 is held at a position where the movable contact 11 and the fixed contact 9 are in contact with each other by the elastic force of the spring 25 of the closing portion 20, and the current breaker 3 is closed. Yes. Therefore, a current flows through the electric circuit 1 through the series circuit of the superconducting element 2 and the current breaker 3 without the current-limiting fixed coil 4.

  When an excessive current flows in the electric circuit 1 due to a short circuit accident or the like from this normal state, an excessive current flows in the superconducting element 2 and the superconducting element 2 is switched from the superconducting state to the non-superconducting state (high resistance state). It commutates to the diverted fixed coil 4 side.

  When a current flows through the current limiting fixed coil 4, a magnetic field is generated, and an electromagnetic repulsive force is generated between the current limiting fixed coil 4 and the electromagnetic repulsion plate 17. Due to this electromagnetic repulsion force, the electromagnetic repulsion plate 17 moves at a high speed downward in the figure as shown in FIG.

  Since the movable conductive rod 12 is connected to the electromagnetic repulsion plate 17 via the movable rod 16, the movable contact 11 moves away from the fixed contact 9, and the current breaker 3 is opened. As a result, current does not flow through the series circuit of the superconducting element 2 and the current breaker 3, but current flows only through the current-limiting fixed coil 4, so that the shunt type superconducting current limiter enters a high impedance state, and Suppresses excessive current flow.

  Further, when the electromagnetic repulsion plate 17 moves downward in the figure, the lid body 23 connected to the electromagnetic repulsion plate 17 via the movable rod 16 also moves in conjunction with the downward movement in the drawing to draw the air in the air chamber 32. It pushes out through the vent 26 and the exhaust 27. Further, at this time, the insulating plate 24 connected to the electromagnetic repulsion plate 17 also moves downward in the figure, so that the spring 25 is compressed and stored.

  Thereafter, as shown in FIG. 4, the spring 25 is released and extended, so that the insulating plate 24 and the electromagnetic repulsion plate 17 move upward in the drawing and are connected to the electromagnetic repulsion plate 17 via the movable rod 16. The movable conductive rod 12 and the lid body 23 are also moved upward in the figure to return the current breaker 3 to the closed state. In this way, the closing operation of the current breaker 3 is automatically performed.

  During this charging operation, air is taken into the air chamber 32 from the outside through the vent hole 26. At this time, the exhaust port 27 is closed by the check valve 28, and air flows into the air chamber 32 only from the vent port 26. At this time, since the atmospheric pressure in the air chamber 32 is lower than the external atmospheric pressure, a force in a direction opposite to the elastic force by the spring 25 is applied to the lid body 23. Thereby, the moving speed to the upper side of the figure of the cover 23 and the movable contact 11 connected with this via the movable rod 16 and the movable conductive rod 12 can be suppressed.

  In this way, the current breaker 3 is automatically turned on after a predetermined time from opening. The time from opening to closing is set by adjusting the size of the diameter of the vent 26 in advance, and about 0.01 to 0.2 seconds is a duty for reclosing the current breaker 3. Preferred to accommodate.

  As described above, according to the first embodiment, the current breaker 3 is opened and turned on by the electromagnetic repulsion force generated between the current limiting fixed coil 4 and the electromagnetic repulsion plate 17 when energized. The spring 25 of the portion 20 is stored, and then the spring 25 is released and extended, and air is taken into the air chamber 32 from the outside through the vent 26, and the lid 23 and the movable contact 11 connected thereto are thus obtained. Since the current breaker 3 is closed by moving the movable contact 11 in a direction approaching the fixed contact 9 while suppressing the movement speed of the current breaker 3, the opening and closing of the current breaker 3 can be performed automatically. Further, since an external power supply is not required, the apparatus can be simplified, downsized, and cost can be reduced.

(Second Embodiment)
FIG. 5 is a connection diagram electrically showing a shunt type superconducting current limiter according to the second embodiment of the present invention, and FIG. 6 is a current cutoff of the shunt type superconducting current limiter according to the second embodiment. It is a block diagram which shows a container and an insertion part. 5 and FIG. 6, the same reference numerals are given to the corresponding parts in FIG. 1 and FIG.

  As shown in FIG. 5, the shunt type superconducting fault current limiter according to the second embodiment is a current breaker 40 connected in parallel to the current breaker 3 with respect to the shunt type superconducting fault limiter shown in FIG. And a current-limiting fixed coil 41 connected in series to the current-limiting fixed coil 4.

  As shown in FIG. 6, in the second embodiment, the current breakers 3 and 40 are arranged in parallel and connected to the electromagnetic repulsion plate 17 and further connected to the input unit 20.

  The current breaker 40 includes a breaker chamber 42, an insulating container 43, lids 44 and 45, a fixed contact 46, a fixed conductive rod 47, a movable contact 48, a movable conductive rod 49, and a bellows 50. The arc shields 51 and 52 are provided and are configured in the same manner as the current breaker 3.

  One end of a movable rod 53 made of an insulator is connected to the end of the current breaker 40 opposite to the side on which the movable contact 48 of the movable conductive rod 49 is fixed. The movable rod 53 is fixed to the electromagnetic repulsion plate 17 so as to penetrate the electromagnetic repulsion plate 17. The other end of the movable rod 53 is fixed to the lid body 23 of the input unit 20.

  Between the current breaker 40 and the electromagnetic repulsion plate 17, a current-limiting fixed coil 41 formed in a cylindrical shape has one end surface facing the electromagnetic repulsion plate 17, and the central opening portion of the movable conductive rod 49. And the movable rod 53 is arrange | positioned so that it may penetrate.

  In the shunt superconducting fault current limiter of the second embodiment configured as described above, during normal energization, the movable contacts 11, 48 are fixed to the fixed contacts 9, 48 by the elastic force of the spring 25 of the closing portion 20. The movable conductive rods 12 and 49 are held at a position in contact with 46, and both the current breakers 3 and 40 are closed. Therefore, a current flows through the electric circuit 1 through the superconducting element 2 and the current breakers 3 and 40 without the current-limiting fixed coils 4 and 41.

  When an excessive current flows in the electric circuit 1 due to a short circuit accident or the like from this normal state, an excessive current flows in the superconducting element 2 and the superconducting element 2 is switched from the superconducting state to the non-superconducting state (high resistance state). It commutates to the diverted fixed coils 4 and 41 side.

  When a current flows through the current limiting fixed coils 4, 41, a magnetic field is generated, and an electromagnetic repulsive force is generated between the current limiting fixed coils 4, 41 and the electromagnetic repulsion plate 17. The operation of opening the current breakers 3 and 40 by this electromagnetic repulsive force and then turning it on is the same as that in the first embodiment, and the description thereof is omitted.

  According to the second embodiment, since the plurality of current breakers 3 and 40 are connected in parallel, in addition to the same effect as the first embodiment, the current capacity of the shunt type superconducting fault current limiter is increased. can do.

  In the second embodiment, an example is shown in which two current breakers and two corresponding current-clamping fixed coils are connected, but the number of current circuit breakers and current-limiting fixed coils is not limited thereto. If more current breakers are used, the current capacity can be increased with the number of current breakers.

  Further, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements 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.

It is a connection diagram which shows electrically the shunt type superconducting fault current limiter concerning a 1st embodiment of the present invention. It is a block diagram which shows the current circuit breaker and injection | throwing-in part of the shunt type | mold superconducting fault current limiter which concern on 1st Embodiment. It is a figure for demonstrating the operation | movement at the time of opening of the electric current circuit breaker shown in FIG. 2, and a making part. It is a figure for demonstrating the operation | movement at the time of the injection | throwing-in of the current circuit breaker shown in FIG. It is a connection diagram which shows electrically the shunt type | mold superconducting fault current limiter concerning the 2nd Embodiment of this invention. It is a block diagram which shows the electric current circuit breaker and injection | throwing-in part of a shunt type | mold superconducting fault current limiter concerning 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric path 2 Superconducting element 3,40 Current breaker 4,41 Current-limiting fixed coil 5,42 Shut-off chamber 6,43 Insulating container 7, 8, 44, 45 Lid body 9,46 Fixed contact 10, 47 Fixed conductive rod 11 , 48 Movable contact 12, 49 Movable conductive rod 13, 50 Bellows 14, 15, 51, 52 Arc shield 16, 53 Movable rod 17 Electromagnetic repulsion plate 20 Input part 21 Bottom wall 22 Side wall 23 Lid 24 Insulation plate 25 Spring 26 Ventilation port 27 Exhaust port 28 Check valve 29 Valve body 30 Valve body 31 Spring 32 Air chamber

Claims (2)

A series circuit in which a superconducting element and a current breaker having a stationary contact and a movable contact facing the stationary contact are connected in series;
A cylindrical current-limiting fixed coil connected in parallel to the series circuit;
An electromagnetic repulsive force that is connected to the movable contact and is disposed to face one end face of the current limiting fixed coil and is generated between the current limiting fixed coil and the current limiting fixed coil when energized. An electromagnetic repulsion plate that opens the current breaker by moving the movable contact in a direction away from the fixed contact;
A bottom wall having an insulating plate coupled to the electromagnetic repulsion plate, an exhaust port provided with a vent and a check valve, a cylindrical side wall erected on one surface of the bottom wall, and the movable A lid connected to the contact and provided in the side wall so as to be reciprocally slidable; and an elastic supporting the insulating plate standing on the bottom wall outside the side wall on the one surface side of the bottom wall. And when the movable contact moves together with the electromagnetic repulsion plate in a direction away from the fixed contact by the electromagnetic repulsive force, the bottom moves by the lid that moves in conjunction with the movable contact. The air in the air chamber surrounded by the wall, the side wall, and the lid is pushed out through the exhaust port and the vent, and the elastic body is compressed by the insulating plate that moves in conjunction with the electromagnetic repulsion plate. After the energy is stored, the elastic body releases and expands Both move the movable contact in a direction approaching the fixed contact while suppressing the moving speed of the cover and the movable contact connected thereto by taking air from the outside into the air chamber through the vent. And a closing means for closing the current breaker. A shunt-type superconducting fault current limiter. A first circuit in which a superconducting element and a parallel circuit in which a plurality of current breakers each having a fixed contact and a movable contact facing the fixed contact are connected in parallel to each other;
A plurality of cylindrical current-limiting fixed coils corresponding to the plurality of current breakers are connected in series with each other, and a second circuit connected in parallel to the first circuit;
Each current limiter is connected to each movable contactor and is arranged to face one end surface of each current limiting fixed coil, and when each current limiting fixed coil is energized, each current limiting fixed An electromagnetic repulsion plate that opens each current breaker by moving each movable contact in a direction away from each corresponding fixed contact of each current breaker by an electromagnetic repulsion force generated between the coil and the coil; ,
An insulating plate connected to the electromagnetic repulsion plate, a bottom wall having a vent and an exhaust port provided with a check valve, a cylindrical side wall erected on one surface of the bottom wall, A lid that is connected to the movable contact and is provided in the side wall so as to be slidable in a reciprocating manner, and supports the insulating plate on the bottom wall outside the side wall on the one surface side of the bottom wall. And when the movable contacts move together with the electromagnetic repulsion plate in a direction away from the corresponding fixed contacts due to the electromagnetic repulsive force, they move in conjunction with the movable contacts. The insulating plate that pushes out air in the air chamber surrounded by the bottom wall, the side wall, and the lid by the lid to the outside through the exhaust port and the vent and moves in conjunction with the electromagnetic repulsion plate After the elastic body is compressed and stored by the above, the elastic body is The movable contact is accommodated while restraining the moving speed of the lid and the movable contacts connected to the lid by taking air from outside into the air chamber through the vents. A shunting type superconducting current limiting device, comprising: closing means for closing each current breaker by moving in a direction approaching each of the fixed contacts.

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