switch

Abstract

The switch (1) includes a fixed electrode (10) connected to an upper terminal (30) connected to a main circuit, a movable electrode (20) that can be moved toward or away from the fixed electrode (10), and an operating device (2) that drives the movable electrode (20). The operating device (2) includes a fixed conductive member that is fixedly disposed, and a movable conductive member that is connected to the movable electrode (20). At least one of the fixed conductive member and the movable conductive member includes a coil that has one end connected to the movable electrode (20) and the other end connected to a lower terminal (40) that is connected to the main circuit. By passing a main circuit current through the main circuit through the coil, electromagnetic repulsion occurs between the fixed conductive member and the movable conductive member, causing an opening operation that separates the movable electrode (20) from the fixed electrode (10).

Description

[Technical Field]

[0001] The present disclosure relates to a switchgear, which is a protective device for an electric power system. [Background technology]

[0002] In switches that require high-speed operation, such as DC circuit breakers, electromagnetic repulsion mechanisms are used as electrode drive devices. The electromagnetic repulsion mechanism includes, for example, a movable repulsion plate made of a conductive material and a drive coil for driving the movable repulsion plate, which is fixed in a position opposite the movable repulsion plate. The drive coils are divided into two types, one for opening and one for closing, and are arranged to sandwich the movable repulsion plate. When current is applied to the drive coil, a magnetic field is generated that penetrates the movable repulsion plate, generating an induced current on the surface of the movable repulsion plate, which then generates a magnetic field from the movable repulsion plate. The electromagnetic repulsive force created by the magnetic fields of the drive coil and the movable repulsion plate drives the movable repulsion plate at high speed in a direction away from the drive coil.

[0003] There is also an electromagnetic repulsion mechanism that uses a moving coil instead of a movable repulsion plate. This generates an electromagnetic repulsive force by passing current through the moving coil and the driving coil so that the magnetic fields generated are in opposite directions, and drives the moving coil at high speed in a direction away from the driving coil. Based on the above operating principle, the movable electrode connected to the repulsion plate or moving coil opens and closes at high speed, making it possible to quickly interrupt or quickly close the arc generated between the electrodes (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 56-126223 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1, if an attempt is made to speed up the operation of the circuit breaker for high-speed circuit protection, it is necessary to increase the power capacity of the drive power supply that drives the drive coil, which poses the problem of increasing the size and cost of the circuit breaker.

[0006] The present disclosure has been made in consideration of the above, and aims to provide a switch that can speed up opening and closing operations without increasing the power capacity of the drive power supply that drives the drive coil, and that can suppress increases in size and cost of the device. [Means for solving the problem]

[0007] To solve the above-mentioned problems and achieve the object, the switch of the present disclosure includes a fixed electrode connected to a first terminal connected to a main circuit, a movable electrode that can be moved toward and away from the fixed electrode, and an operating device that drives the movable electrode. The operating device includes a fixed conductive member that is fixedly disposed, and a movable conductive member that is connected to the movable electrode. At least one of the fixed conductive member and the movable conductive member includes a coil that has one end connected to the movable electrode and the other end connected to a second terminal that is connected to the main circuit. The main circuit current that flows through the main circuit always flows through the coil, and when a fault current occurs, By passing a main circuit current through the main circuit through the coil, the fixed conductive member and the movable conductive member are electromagnetically repelled, and an opening operation is performed in which the movable electrode is separated from the fixed electrode. [Effects of the Invention]

[0008] The switch of the present disclosure has the advantage that the switching operation can be speeded up without increasing the power capacity of the drive power supply that drives the drive coil, and that increases in size and cost of the device can be suppressed. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view showing a configuration of a switch in a closed state according to a first embodiment; [Figure 2] FIG. 10 is a schematic cross-sectional view showing a configuration of a modified example of the switch according to the first embodiment; [Figure 3]FIG. 1 is a schematic cross-sectional view showing a configuration of a switch according to a first embodiment in an open state; [Figure 4] FIG. 1 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a first embodiment; [Figure 5] FIG. 10 is a schematic cross-sectional view showing the configuration of a switch in a closed state according to a second embodiment; [Figure 6] FIG. 10 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a second embodiment. [Figure 7] FIG. 10 is a schematic cross-sectional view showing the configuration of a switch in a closed state according to a third embodiment; [Figure 8] FIG. 10 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a third embodiment. [Figure 9] FIG. 10 is a schematic cross-sectional view showing the configuration of a switch in a closed state according to a fourth embodiment; [Figure 10] FIG. 10 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a fourth embodiment. [Figure 11] FIG. 10 is a schematic cross-sectional view showing a partial configuration of a switch according to a fifth embodiment. [Figure 12] FIG. 13 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a fifth embodiment. [Figure 13] FIG. 13 is a schematic cross-sectional view showing the configuration of a switch according to a sixth embodiment in a closed state; [Figure 14] FIG. 13 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a sixth embodiment. [Figure 15] FIG. 13 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a sixth embodiment, and shows the circuit configuration in an initial state. [Figure 16] FIG. 13 is a diagram showing a circuit configuration for performing an opening operation on a switch according to a sixth embodiment, and shows the circuit configuration in an abnormal state. [Figure 17] FIG. 13 is a diagram showing a circuit configuration of a switch according to a seventh embodiment. [Figure 18] FIG. 13 is a diagram showing a circuit configuration of a switch according to a seventh embodiment, and is a diagram showing an example of an auxiliary interrupter circuit. [Figure 19] FIG. 13 is a diagram showing a circuit configuration of a switch according to a seventh embodiment, and is a diagram showing another example of an auxiliary interrupter circuit. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a switch according to an embodiment will be described in detail with reference to the drawings.

[0011] Embodiment 1 Fig. 1 is a schematic cross-sectional view showing the configuration of a switch 1 according to the first embodiment in a closed state. As shown in Fig. 1, the up-down direction and the left-right direction are defined. The direction in which the fixed electrode 10 and the movable electrode 20 move toward and away from each other is defined as the up-down direction, and the direction perpendicular to the up-down direction is defined as the left-right direction.

[0012] The overall configuration of the switchgear 1 will be described with reference to FIG. 1. As shown in FIG. 1, the switchgear 1 includes, from above, an arc-extinguishing chamber 50 including a fixed electrode 10 and a movable electrode 20, an operating device 2 for operating the movable electrode 20, and a holding mechanism 120 for holding the movable electrode 20 in an open or closed position. In the open position, the movable electrode 20 is spaced apart from the fixed electrode 10, and in the closed position, the movable electrode 20 is in contact with the fixed electrode 10. The arc-extinguishing chamber 50 is covered with a cover 60. An upper terminal 30 serving as a first terminal is provided on the top surface of the cover 60, and an opening (not shown) is provided on the side of the cover 60. A lower terminal 40 serving as a second terminal is fixed in the opening, and the upper terminal 30 and the lower terminal 40 are each connected to a main circuit (not shown). The main circuit has an electric circuit connecting a power supply side terminal (not shown) and a load side terminal (not shown) of the switchgear 1, which serves as a circuit breaker. The atmosphere in the arc extinguishing chamber 50 may be any of gas, vacuum, gas, oil, and liquid.

[0013] Although not shown in detail, the holding mechanism 120 may be a mechanism using a disc spring, a link mechanism, or a magnetic mechanism using an electromagnet or a permanent magnet. The operating device 2 includes an opening coil 80, which is a fixed spiral-shaped conductive member, a closing coil 100, which is also a fixed spiral-shaped conductive member, and a repulsion plate 90, which is a plate-shaped movable conductive member. The opening coil 80 is surrounded by a holder 81. Because the opening coil 80 does not need to be insulated, the holder 81 may be made of a material other than an insulating material. On the other hand, the closing coil 100 is surrounded by a holder 110 made of an insulating material and is insulated.

[0014] Next, the connections of the components of the switch 1 will be described. The upper terminal 30 is connected to a fixed electrode rod 31, and the fixed electrode 10 is connected to the underside of the fixed electrode rod 31. The movable electrode 20 faces the fixed electrode 10, and the movable electrode rod 21 is connected to the underside of the movable electrode 20. The movable electrode rod 21 is connected to a movable shaft 22 via a rod 23. The fixed electrode rod 31, the movable electrode rod 21, and the movable shaft 22 extend in the vertical direction. The movable shaft 22 and the rod 23 may be conductive members, and the movable electrode rod 21 and the movable shaft 22 may be integral with each other.

[0015] The repulsion plate 90 is connected to the movable shaft 22 so that its central axis coincides with that of the movable shaft 22. Furthermore, the opening coil 80 and the closing coil 100 are arranged so that the central axes of their windings coincide with that of the movable shaft 22. That is, the structure allows the movable shaft 22 to pass through the center of the opening coil 80 and the center of the closing coil 100. The opening coil 80 is located above the closing coil 100. The holder 81 for the opening coil 80 and the holder 110 for the closing coil 100 are arranged facing each other at a fixed distance in the vertical direction via multiple support columns 82. The repulsion plate 90, connected to the movable shaft 22, is located in the space between the opening coil 80 and the closing coil 100. The holder 110 for the closing coil 100 is supported by multiple support columns 130. A holding mechanism 120 is fixed in the space between the support columns 130 and is connected to the movable shaft 22.

[0016] Next, the current path between the upper terminal 30 and the lower terminal 40 will be described. The movable terminal 41 is connected to the movable electrode rod 21, which is connected to the movable electrode 20. The movable terminal 41 and one end of the opening coil 80 are connected in series by a flexible conductor 70, and the other end of the opening coil 80 and the lower terminal 40 are connected in series by a flexible conductor 71. In this way, the movable electrode 20 and the opening coil 80 are at the same potential, and a main circuit current flows in the main circuit between the upper terminal 30 and the lower terminal 40 through a path that includes the fixed electrode 10, the movable electrode 20, and the opening coil 80.

[0017] Next, insulation will be described. FIG. 2 is a schematic cross-sectional view showing the configuration of a modified example of the switchgear 1 according to the first embodiment. In FIG. 2, a cylindrical or rectangular parallelepiped insulating tube 300 is provided to provide insulation from the external environment. The insulating tube 300 includes an insulating tube 300a surrounding the arc extinguishing chamber 50, an insulating tube 300b surrounding the operating device 2, and an insulating tube 300c surrounding the holding mechanism 120. The upper end of the insulating tube 300a is fixed to the lower surface of the upper terminal 30, and the lower end of the insulating tube 300a is fixed to the upper surface of the holder 81 of the opening coil 80. The upper end of the insulating tube 300b is fixed to the lower surface of the holder 81 of the opening coil 80, and the lower end of the insulating tube 300b is fixed to the upper surface of the holder 110 of the closing coil 100. The upper end of the insulating tube 300c is fixed to the lower surface of the holder 110 of the closing coil 100. The insulating tube 300a may also serve as the cover 60. The insulating tube 300 is fixed using bolts, and multiple bolt holes are provided in the top and bottom surfaces of holder 81 of opening coil 80 and holder 110 of closing coil 100, and the insulating tubes 300a to 300c are fastened together so as to sandwich holders 81, 110. Note that insulating tubes 300a, 300b may be made of a translucent resin material such as polycarbonate, so that the open / closed state of the movable part can be confirmed.

[0018] Next, the operation of the switch 1 will be described with reference to FIGS. 1 and 3. FIG. 3 is a schematic cross-sectional view showing the configuration of the switch 1 according to the first embodiment in an open state. In the closed state shown in FIG. 1, when a current is applied to the opening coil 80, a magnetic flux is generated, and the magnetic flux penetrates the upper and lower surfaces of the repulsion plate 90. At this time, an induced electromotive force is generated in the repulsion plate 90, causing an induced current to flow. Then, a magnetic flux is generated in the repulsion plate 90 in the opposite direction to the magnetic flux generated by the opening coil 80, generating an electromagnetic repulsive force. This electromagnetic repulsive force moves the repulsion plate 90 downward. The repulsion plate 90 is connected to the movable shaft 22, which is connected to the movable electrode rod 21 and the movable electrode 20. Therefore, when the repulsion plate 90 moves downward, the movable electrode 20 opens from the fixed electrode 10, resulting in the state shown in FIG. 3. After the opening operation of the movable electrode 20, the open state is maintained by the holding mechanism 120. The closing operation from Figure 3 to Figure 1 operates on the same principle, but in the opposite direction. When current is applied to the closing coil 100, an upward electromagnetic repulsive force is generated in the repulsion plate 90, bringing the movable electrode 20 into contact with the fixed electrode 10.

[0019] Next, a circuit for opening and closing the movable electrode 20 will be described. Fig. 4 is a diagram showing a circuit configuration for performing an opening operation of the switch 1 according to the first embodiment. Fig. 4 shows the electrical connection between the fixed electrode 10 and the movable electrode 20 in the arc extinguishing chamber 50 and the opening coil 80. A main circuit (not shown) connected to the upper terminal 30 and the lower terminal 40 of the switch 1 is connected in series with the opening coil 80, and a drive power supply 150 is connected in parallel to the opening coil 80.

[0020] In order to prevent the conductor of the opening coil 80 from melting or burning due to heat generated when the main circuit current is flowing, the conductor cross-sectional area of ​​the opening coil 80 must be designed to suit the rated current value and the fault current value, and for example, in electric systems in the medium to high voltage range, the coil may have a shape formed by winding a copper plate in a spiral shape. In addition, in the first embodiment, since the opening operation is not performed by a current that is constantly flowing, the closing holding force of the holding mechanism 120 is designed to be greater than the electromagnetic repulsive force when a current is constantly flowing and smaller than the electromagnetic force when a fault current occurs.

[0021] On the other hand, although the closing operation is not shown in the figure, the driving power supply for closing is connected to the closing coil 100, and when a closing operation command is input to the driving power supply, current is passed through the closing coil 100, and an upward electromagnetic repulsive force is generated in the repulsion plate 90, causing the movable electrode 20 to perform a closing operation.

[0022] According to the first embodiment, the movable electrode 20 can be opened by utilizing not only the energy from the driving power supply 150 but also the energy of the main circuit by directly energizing the opening coil 80 with the fault current flowing through the main circuit. This enables faster opening without changing the power capacity of the driving power supply used for the opening coil 80, which helps prevent the increase in size and cost that comes with higher speeds. Furthermore, since the opening coil 80 and the main circuit can be configured at the same potential, no insulating member is required for the opening coil 80, and the initial gap in the vertical direction between the opening coil 80 and the repulsion plate 90 in the closed position can be reduced, which improves the electromagnetic repulsive force in the initial position.

[0023] Embodiment 2 5 is a schematic cross-sectional view showing the configuration of a switch 1a according to the second embodiment in a closed state. In the second embodiment, the operating device 2 of the first embodiment is replaced with an operating device 2a. The operating device 2a includes a moving coil 160 which is a spiral-shaped movable conductive member, an opening repulsion plate 170 which is a plate-shaped fixed conductive member, and a closing repulsion plate 171 which is also a plate-shaped fixed conductive member. The other configurations in the second embodiment are the same as those in the first embodiment, and therefore redundant explanations will be omitted.

[0024] The movable coil 160 is surrounded by a holder 161. The holder 161 of the movable coil 160 is connected to the movable shaft 22 so that its central axis coincides with that of the movable shaft 22. The movable terminal 41 and one end of the movable coil 160 are connected in series by a flexible conductor 70, and the other end of the movable coil 160 and the lower terminal 40 are connected in series by the flexible conductor 71. In this way, the movable electrode 20 and the movable coil 160 are at the same potential, and a main circuit current flows in the main circuit between the upper terminal 30 and the lower terminal 40 through a path including the fixed electrode 10, the movable electrode 20, and the movable coil 160.

[0025] 6 is a diagram showing a circuit configuration for performing an opening operation of the switch 1a according to the second embodiment. A main circuit (not shown) connected to the upper terminal 30 and the lower terminal 40 of the switch 1a is connected in series with a moving coil 160, and a drive power supply 150 is connected in parallel with the moving coil 160.

[0026] When a current is passed through the moving coil 160, a magnetic flux is generated, and the magnetic flux penetrates the opening repulsion plate 170. At this time, an induced electromotive force is generated in the opening repulsion plate 170, and an induced current flows. Then, a magnetic flux is generated in the opening repulsion plate 170 in the opposite direction to the magnetic flux generated by the moving coil 160, and an electromagnetic repulsive force is generated. This electromagnetic repulsive force moves the moving coil 160 downward. The moving coil 160 is connected to the moving shaft 22, and the moving electrode 20 opens from the fixed electrode 10. After the opening operation of the moving electrode 20, the open state is maintained by the holding mechanism 120.

[0027] According to the second embodiment, as in the first embodiment, the main circuit current can be utilized for the contact opening operation, and in addition, the number of coil components, which are more expensive than plate materials, can be reduced, thereby realizing cost reduction.

[0028] Embodiment 3 FIG. 7 is a schematic cross-sectional view showing the configuration of a switch 1b according to the third embodiment in a closed state. FIG. 8 is a diagram showing a circuit configuration for performing an opening operation on the switch 1b according to the third embodiment. In the third embodiment, an operating device 2b is provided. In the third embodiment, the movable coil 160, which is a movable conductive member, and the opening coil 80 and closing coil 100, which are fixed conductive members, are all formed of spiral-shaped conductive members. The movable coil 160 is surrounded by a holder 161. The opening coil 80 is surrounded by a holder 81, and the closing coil 100 is surrounded by a holder 110. The opening coil 80 of the third embodiment corresponds to the first coil, and the movable coil 160 of the third embodiment corresponds to the second coil.

[0029] In the third embodiment, at least one of the movable coil 160 and the opening coil 80 is disposed in a location where the main circuit current flows between the movable terminal 41 and the lower terminal 40, and the main circuit current is utilized for the opening operation.

[0030] 7 and 8, the moving coil 160 is placed in a location where the main circuit current flows, and the opening coil 80 is driven by a driving power supply 150. The moving terminal 41 and one end of the moving coil 160 are connected in series by a flexible conductor 70, and the other end of the moving coil 160 and the lower terminal 40 are connected in series by a flexible conductor 71. The opening coil 80 is connected to the driving power supply 150. The moving electrode 20 and the moving coil 160 are at the same potential, and the main circuit current flows through a path that includes the moving electrode 20 and the moving coil 160. The opening coil 80 is driven by the driving power supply 150. Although not shown, the closing coil 100 is also connected to the driving power supply.

[0031] Note that the main circuit current may be passed through a path including the movable electrode 20 and the opening coil 80, and a drive power supply may be connected to the movable coil 160. Alternatively, the main circuit current may be passed through a path including the movable electrode 20, the opening coil 80, and the moving coil 160. In addition, in FIG. 8 , the main circuit current may be passed through both the opening coil 80 and the moving coil 160 by connecting the movable terminal 41 to one end of the opening coil 80 and connecting the other end of the opening coil 80 to the lower terminal 40.

[0032] According to the third embodiment, the main circuit current can be utilized for the contact opening operation, as in the first embodiment. Furthermore, since the contact opening operation is realized by opposing coils, the magnetic field strength is higher than when the repulsion plate 90 and the opening repulsion plate 170 are opposed to the coils, and the electromagnetic repulsive force can be improved, thereby speeding up the contact opening operation.

[0033] Embodiment 4 FIG. 9 is a schematic cross-sectional view showing the configuration of a switch 1c according to the fourth embodiment in a closed state. FIG. 10 is a diagram showing a circuit configuration for performing an opening operation on the switch 1c according to the fourth embodiment. In the fourth embodiment, an operating device 2c is provided. In contrast to the configurations of FIGS. 7 and 8, the moving coil 160 and the opening coil 80 are connected by a flexible conductor 73, so that the moving coil 160 and the opening coil 80 have the same potential. In the fourth embodiment, components that achieve the same functions as those in the third embodiment are given the same reference numerals, and redundant explanations will be omitted.

[0034] The movable coil 160 and the opening coil 80 are connected in series. The opening coil 80 has a larger diameter or cross-sectional area of ​​the winding than the opening coil 80 of the third embodiment in order to suppress heat generation when the main circuit current is continuously passed through.

[0035] According to the fourth embodiment, the movable coil 160 and the opening coil 80 are connected in series, so that the phase of the current flowing through the movable coil 160 and the phase of the current flowing through the opening coil 80 when current flows due to an accident are aligned, generating a larger electromagnetic repulsive force than in the third embodiment, thereby enabling the opening operation to be performed at a higher speed.

[0036] Embodiment 5. FIG. 11 is a schematic cross-sectional view showing a partial configuration of a switch 1d according to a fifth embodiment. FIG. 12 is a diagram showing a circuit configuration for performing an opening operation of the switch 1d according to the fifth embodiment. The fifth embodiment includes an operating device 2d. In the fifth embodiment, two types of coils are provided, one connected to the main circuit and the other connected to the drive power source 150, in place of either or both of the opening coil 80 and the moving coil 160 of the first to fourth embodiments. In FIGS. 11 and 12, the opening coil 80 of the first embodiment is configured to include two types of coils: an opening coil 80a connected to the main circuit and an opening coil 80b connected to the drive power source 150. The opening coil 80a corresponds to the third coil, and the opening coil 80b corresponds to the fourth coil. The opening coils 80a and 80b have different numbers of turns or cross-sectional areas.

[0037] The opening coil 80b is entirely surrounded by a resin holder to insulate it from the main circuit. The opening coil 80a and the opening coil 80b may be configured in two layers, one above the other, and either the upper or lower side may be connected to the main circuit. Furthermore, although not shown, they may also have a two-layer cylindrical structure, and either the inner or outer side may be connected to the main circuit.

[0038] According to the fifth embodiment, the opening coil 80 and the movable coil 160 of the first to fourth embodiments are provided with coils for connecting the main circuit and the driving power supply, respectively. This allows for designing each coil to match the specifications of the power supply. This allows for optimal coil design, maximizing the electromagnetic repulsion acting on the repulsion plate 90. For example, in the event of a short-circuit fault, a large current flows through the main circuit. This necessitates design constraints due to heat generated when the coil is continuously energized, necessitating a larger coil diameter. However, increasing the coil diameter prevents an increase in the number of turns, making it impossible to maximize the magnetomotive force of the coil connected to the driving power supply. On the other hand, when coils for connecting the main circuit and the driving power supply are provided as in the fifth embodiment, the number of turns and wire diameter of the coil connected to the driving power supply 150 can be designed to match the specifications of the driving power supply 150, eliminating the need to design them to match the specifications of the coil on the main circuit side. This allows for effective utilization of the energy of both the main circuit and the driving power supply 150.

[0039] The moving coil 160 in the second to fourth embodiments may include two types of coils: one connected to the main circuit and the other connected to the drive power supply 150.

[0040] Embodiment 6 FIG. 13 is a schematic cross-sectional view showing the configuration of a switch 1e according to a sixth embodiment in a closed state. FIG. 14 is a diagram showing a circuit configuration for performing an opening operation on the switch 1e according to the sixth embodiment. The sixth embodiment includes an operating device 2e. The sixth embodiment differs from the first embodiment in that it is provided with a flexible conductor 72 and two switches, a first switch 140 and a second switch 141. In the sixth embodiment, components that achieve the same functions as those in the first embodiment are given the same reference numerals, and redundant explanations will be omitted.

[0041] The movable terminal 41 and one end of the opening coil 80 are connected in series by a flexible conductor 70, and the other end of the opening coil 80 and the lower terminal 40 are connected in series by a flexible conductor 71. The movable terminal 41 and the lower terminal 40 are connected by a flexible conductor 72. A driving power supply 150 is connected in parallel to the opening coil 80. A first switch 140 is provided in series with the flexible conductor 70. The first switch 140 may be provided in the flexible conductor 71. A second switch 141 is provided in series with the flexible conductor 72. In FIG. 14 , the first switch 140 and the second switch 141 are off. The current path in which the first switch 140 is provided corresponds to the first current path, and the current path in which the second switch 141 is provided corresponds to the second current path.

[0042] The operations of the first switch 140 and the second switch 141 will be described with reference to Fig. 15 and Fig. 16. Fig. 15 is a diagram showing a circuit configuration for opening the switch 1e according to the sixth embodiment, and is a diagram showing the circuit configuration in an initial state. Fig. 16 is a diagram showing a circuit configuration for opening the switch 1e according to the sixth embodiment, and is a diagram showing the circuit configuration in an abnormal state.

[0043] As shown in FIG. 15, when the switch 1e is in a normal closed state, the first switch 140 is off and the second switch 141 is on. Therefore, as shown by arrow E1, current flows from the movable terminal 41 to the lower terminal 40 via the second switch 141 without passing through the opening coil 80. On the other hand, as shown in FIG. 16, when an accident occurs, commands are input to the first switch 140 and the second switch 141, turning the first switch 140 on and the second switch 141 off. As a result, current flows from the movable terminal 41 to the lower terminal 40 via the first switch 140 and the opening coil 80, as shown by arrows E2 and E3. Current also flows from the drive power supply 150 to the opening coil 80, as shown by the dashed arrow. When the opening coil 80 is energized, the repulsion plate 90 moves downward, as described above, and the movable electrode 20 separates from the fixed electrode 10. When the switch 1e is turned on, that is, when the switch 1e is activated and put into a closed state, the first switch 140 and the second switch 141 are reset to the initial state shown in FIG.

[0044] According to the sixth embodiment, the first switch 140 and the second switch 141 are provided, and therefore, under normal circumstances, no current is passed through the opening coil 80, and therefore no electromagnetic repulsion is generated by the opening coil 80. This eliminates the need to strengthen the holding force between the fixed electrode 10 and the movable electrode 20, which would hinder the opening operation. Furthermore, since no current is passed through the opening coil 80 in the normal closed state, heat is not generated during continuous current passing through, improving the reliability of the switch 1e. Furthermore, since the first switch 140 and the second switch 141 are reset when the switch 1e is closed, no electromagnetic repulsion in the opening direction is generated when the main circuit current is passed through the opening coil 80 during the power-on operation, and the switch 1e can be safely closed.

[0045] Note that embodiment 6 may be applied to embodiments 2 to 5. For example, even when the movable conductive member is movable coil 160, a first switch 140 is similarly connected in series between flexible conductor 70 connecting movable terminal 41 and movable coil 160, and a second switch 141 is similarly connected in series between flexible conductor 72 connecting movable terminal 41 and lower terminal 40.

[0046] Embodiment 7 Fig. 17 is a diagram showing a circuit configuration of a switch 1f according to a seventh embodiment. Fig. 18 is a diagram showing a circuit configuration of a switch 1f according to the seventh embodiment, and is a diagram showing an example of an auxiliary interrupter circuit 200. Fig. 19 is a diagram showing a circuit configuration of a switch 1f according to the seventh embodiment, and is a diagram showing another example of the auxiliary interrupter circuit 200.

[0047] The seventh embodiment relates to a DC circuit breaker. Since DC current has no current zero point and is difficult to interrupt, a current zero point is forcibly generated and interrupted by superimposing a current opposite to the short-circuit current. For this reason, the DC interrupting circuit is provided with a disconnection auxiliary circuit 200 that generates a zero point. In the seventh embodiment, the disconnection auxiliary circuit 200 is connected in parallel between the upper terminal 30 and the lower terminal 40 of the switches 1, 1a to 1e of the first to sixth embodiments, and a high-frequency current generated by a zero point generating circuit in the disconnection auxiliary circuit 200 is superimposed. In Figs. 17 to 19, the disconnection auxiliary circuit 200 is added to the switch 1 of the first embodiment.

[0048] 18, the interrupter auxiliary circuit 200 includes an LC resonant circuit having a capacitor 202, an inductor 201, and a lightning arrester 400, and a closing switch 401. When a fault occurs, i.e., when the switch 1f is opened, the closing switch 401 is closed, thereby superimposing a high-frequency current generated in the LC resonant circuit. FIG. 19 shows another example of the interrupter auxiliary circuit 200, which includes an expanded resonant circuit having a capacitor 202, an inductor 201, a VSC (Voltage Sourced Converter) 203, and the lightning arrester 400. Note that the inductor 201 may be shared with the opening coil 80 or the moving coil 160 of any of the first to sixth embodiments.

[0049] According to the seventh embodiment, the auxiliary interrupting circuit 200 is connected in parallel between the upper terminal 30 and the lower terminal 40, so that a high-frequency current can be superimposed on the main circuit current when the switch 1f opens. Because a current with a higher frequency than a normal fault current is superimposed on the main circuit current, a large induced current flows through the opening coil 80 or the moving coil 160, etc., through which the superimposed current flows. This generates a large electromagnetic repulsive force, realizing a high-speed opening operation. Therefore, according to the seventh embodiment, a DC circuit breaker capable of high-speed opening operation can be realized.

[0050] The configurations shown in the above embodiments are examples of the contents of the present disclosure, and may be combined with other known technologies, or the respective embodiments may be combined, and part of the configuration may be omitted or modified within the scope that does not deviate from the gist of the present disclosure. [Explanation of symbols]

[0051] 1, 1a, 1b, 1c, 1d, 1e, 1f switch, 2, 2a, 2b, 2c, 2d, 2e operating device, 10 fixed electrode, 20 movable electrode, 21 movable electrode rod, 22 movable shaft, 23 rod, 30 upper terminal, 31 fixed electrode rod, 40 lower terminal, 41 movable terminal, 50 arc extinguishing chamber, 60 cover, 70, 71, 72, 73 flexible conductor, 80, 80a, 80b opening coil, 81, 110, 161 holder, 82, 130 support, 90 repulsion plate, 100 closing coil, 120 holding mechanism, 140 first switch, 141 second switch, 150 driving power supply, 160 moving coil, 170 opening repulsion plate, 171 closing repulsion plate, 200 Auxiliary interrupting circuit, 201 inductor, 202 capacitor, 203 VSC, 300, 300a, 300b, 300c insulating tube, 400 lightning arrester, 401 closing switch.

Claims

1. A fixed electrode connected to the first terminal connected to the main circuit, A movable electrode that can move toward and away from the fixed electrode, The system includes an operating device for driving the movable electrode, The aforementioned operating device is A fixed conductive member that is fixedly positioned, The movable electrode comprises a movable conductive member connected to the movable electrode, At least one of the fixed conductive member and the movable conductive member includes a coil, one end of which is connected to the movable electrode and the other end of which is connected to a second terminal connected to the main circuit. The coil is constantly supplied with the main circuit current that flows through the main circuit. When a fault current occurs, the coil is supplied with the main circuit current, causing electromagnetic repulsion between the fixed conductive member and the movable conductive member, thereby performing an opening operation that separates the movable electrode from the fixed electrode. A switch characterized by the following features.

2. A holding mechanism that holds the movable electrode in the closed electrode position, wherein the closed electrode holding force is greater than the electromagnetic repulsive force between the fixed conductive member and the movable conductive member when current is constantly flowing, and smaller when the fault current occurs. The switch according to feature 1.

3. The movable conductive member is a plate member, The fixed conductive member has the coil, The main circuit current flows through a path including the first terminal, the fixed electrode, the movable electrode, the coil of the fixed conductive member, and the second terminal. The switch according to feature 1.

4. The aforementioned fixed conductive member is a plate member, The movable conductive member has the coil, The main circuit current flows through a path including the first terminal, the fixed electrode, the movable electrode, the coil of the movable conductive member, and the second terminal. The switch according to feature 1.

5. The fixed conductive member has a first coil as the coil, The movable conductive member has a second coil as the coil, At least one of the first coil and the second coil is connected to the movable electrode and the second terminal, The main circuit current flows through a path including the first terminal, the fixed electrode, the movable electrode, at least one of the first coil and the second coil, and the second terminal. The switch according to feature 1.

6. Connect the power supply to the aforementioned coil. A switch according to any one of features 1 to 5.

7. A fixed electrode connected to a first terminal connected to the main circuit, A movable electrode that can move toward and away from the fixed electrode, The system includes an operating device for driving the movable electrode, The aforementioned operating device is A fixed conductive member that is fixedly positioned, The movable electrode comprises a movable conductive member connected to the movable electrode, At least one of the fixed conductive member and the movable conductive member includes a coil, one end of which is connected to the movable electrode and the other end of which is connected to a second terminal connected to the main circuit. By passing the main circuit current flowing through the main circuit through the coil, the fixed conductive member and the movable conductive member are electromagnetically repelled, causing the movable electrode to open and separate from the fixed electrode. The coil comprises a third coil connected to the movable electrode and a fourth coil connected to the drive power supply, and the number of turns or cross-sectional area of ​​the third coil and the fourth coil are different. A switch characterized by the following features.

8. A fixed electrode connected to a first terminal connected to the main circuit, A movable electrode that can move toward and away from the fixed electrode, The system includes an operating device for driving the movable electrode, The aforementioned operating device is A fixed conductive member that is fixedly positioned, The movable electrode comprises a movable conductive member connected to the movable electrode, At least one of the fixed conductive member and the movable conductive member includes a coil, one end of which is connected to the movable electrode and the other end of which is connected to a second terminal connected to the main circuit. By passing the main circuit current flowing through the main circuit through the coil, the fixed conductive member and the movable conductive member are electromagnetically repelled, causing the movable electrode to open and separate from the fixed electrode. The circuit further includes a blocking auxiliary circuit that, when open, superimposes a high-frequency current onto the main circuit current flowing between the first terminal and the second terminal. A switch characterized by the following features.

9. The aforementioned interruption auxiliary circuit includes an LC resonant circuit having a capacitor and an inductor. The switch according to claim 8.

10. The aforementioned interruption auxiliary circuit includes an expanded resonant circuit having a capacitor, an inductor, and a voltage converter. The switch according to claim 8.

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