High-speed input device, power conversion device, and power reception and distribution equipment

Abstract

A high-speed input device (101) comprises a first electrode (10) and a second electrode (20) that is movable in a first direction (DR1) toward the first electrode. The second electrode can move from a first position set apart from the first electrode in the first direction to a second position where contact is made with the first electrode. The high-speed input device further comprises a discharge induction mechanism (70) for inducing discharge between the second electrode and the first electrode. The discharge induction mechanism includes a trigger electrode (71) that can move together with the second electrode. The second electrode has an end surface (20A) facing the first electrode in the first direction. The second electrode is provided with a tapered hole (20H) which opens in the end surface and the hole diameter of which decreases as the distance from the end surface increases. The trigger electrode has a tip part (71A) disposed inside the tapered hole.

Description

High-speed switch, power conversion device, and power distribution equipment

[0001] The present disclosure relates to a high-speed switch, a power conversion device including the high-speed switch, and a power distribution equipment.

[0002] The microfilm of Japanese Utility Model Application No. 62-13775 (Japanese Utility Model Publication No. 63-123026) (Patent Document 1) discloses a high-speed switching device including a fixed electrode, a movable electrode, a trigger electrode, a trigger voltage generation unit, and a control unit. In the high-speed switching device, the trigger voltage generation unit that has received a start signal applies a trigger voltage between the fixed electrode and the trigger electrode. After a trigger discharge occurs between the fixed electrode and the trigger electrode, a discharge subsequently occurs between the movable electrode and the fixed electrode due to the influence of the trigger discharge.

[0003] In the high-speed switching device described in Patent Document 1, in order to prevent the consumption of the trigger electrode, the trigger electrode is provided in a recess formed inside the fixed electrode. The recess is wider than an opening that opens to the contact surface of the fixed electrode.

[0004] Microfilm of Japanese Utility Model Application No. 62-13775 (Japanese Utility Model Publication No. 63-123026)

[0005] However, in order to stably generate a trigger discharge between the fixed electrode and the trigger electrode provided in the recess thereof, a high voltage is required.

[0006] A main object of the present disclosure is to provide a high-speed switch, a power conversion device, and a power distribution equipment that can stably generate a trigger discharge with a lower voltage while suppressing the wear of the trigger electrode.

[0007] The high-speed inlet according to this disclosure comprises a first electrode and a second electrode movable in a first direction toward the first electrode. The second electrode is movable from a first position spaced apart from the first electrode in the first direction to a second position in contact with the first electrode. The high-speed inlet further comprises a discharge induction mechanism for inducing a discharge between the second electrode and the first electrode. The discharge induction mechanism includes a trigger electrode movable together with the second electrode. The second electrode has an end face facing the first electrode in the first direction. The second electrode is provided with a tapered hole that opens at the end face and whose diameter decreases as it moves away from the end face. The trigger electrode has a tip portion located inside the tapered hole.

[0008] According to this disclosure, it is possible to provide a high-speed switch, a power converter, and power distribution equipment that can stably generate a trigger discharge at a lower voltage while suppressing wear of the trigger electrode.

[0009] This is a cross-sectional view showing a high-speed switch according to Embodiment 1. This is a partially enlarged cross-sectional view showing region II in Figure 1. This is a partially enlarged cross-sectional view showing region III in Figure 2. This is a cross-sectional view showing the operating state realized during the switching operation in the high-speed switch according to Embodiment 1. This is a cross-sectional view showing the state in which the second electrode is switched onto the first electrode in the high-speed switch according to Embodiment 1. This is a cross-sectional view showing a high-speed switch according to Embodiment 2. This is a partially enlarged cross-sectional view showing region VII in Figure 6. This is a cross-sectional view showing a high-speed switch according to Embodiment 3. This is a cross-sectional view showing the operating state realized during the switching operation in the high-speed switch according to Embodiment 3. This is a cross-sectional view showing the state in which the first electrode and the second electrode are switched onto each other in the high-speed switch according to Embodiment 3. This is a diagram showing an example of a power control circuit included in a power conversion device according to Embodiment 4. This is a diagram showing an example of a power distribution circuit included in a power distribution equipment according to Embodiment 5.

[0010] Embodiments of this disclosure will be described below with reference to the drawings. The same reference numerals will be used for identical components, and their descriptions will not be repeated.

[0011] The high-speed switch according to this embodiment is electrically connected in parallel to one module circuit in an electrical device having multiple module circuits. When one module circuit fails, the high-speed switch short-circuits both ends of that module circuit to disable it, preventing the effects of the failure from spreading to other module circuits. The high-speed switch according to this disclosure is applicable to any electrical device. As an example, the high-speed switch according to this disclosure is applicable to a power converter. In a power converter, the high-speed switch according to this disclosure is connected in parallel to each module circuit, protecting each of the multiple module circuits (unit converters). As another example, the high-speed switch according to this disclosure is applicable to power distribution equipment. In power distribution equipment, the high-speed switch according to this disclosure is connected between one pole of the circuit breaker of each switchgear and the ground conductor, protecting multiple module circuits (switchgears).

[0012] Embodiment 1. <Configuration of the high-speed feeder> As shown in Figures 1 to 5, the high-speed feeder 101 of Embodiment 1 comprises a first electrode 10, a second electrode 20, a guide portion 30, a holding portion 41, a first drive portion 50, and a discharge induction mechanism 70.

[0013] The first electrode 10 is a fixed electrode. The second electrode 20 is a movable electrode. The guide portion 30 guides the movement of the second electrode 20. The second electrode 20 is electrically connected to the guide portion 30 and is movable relative to the first electrode 10 and the guide portion 30.

[0014] The second electrode 20 is movable from a first position where it is spaced apart from the first electrode 10 to a second position where it is in contact with the first electrode 10.

[0015] In this specification, the state in which the second electrode 20 is in the first position is described as the first state, and the state in which the second electrode 20 is in the second position is described as the second state.

[0016] Figure 1 shows the first state of the high-speed feeder 101. Figure 4 shows the operating state achieved after the second electrode 20 begins to move from the first position to the second position. Figure 5 shows the second state of the high-speed feeder 101.

[0017] In this specification, the direction of movement of the second electrode 20 is described as the first direction DR1. The first direction DR1 may be along the vertical direction. In this case, it is preferable that the second electrode 20 is positioned above the first electrode 10. The first direction DR1 may also be along the horizontal direction. The central axis that passes through the center of the second electrode 20 and extends along the first direction DR1 when viewed from the first direction DR1 is described as the central axis CA. The radial direction relative to the central axis CA is described as the second direction DR2.

[0018] The first electrode 10 has an end face 10A facing the second electrode 20 in the first direction DR1. The end face 10A is, for example, a convex surface. The end face 10A may also be a flat or concave surface. The second electrode 20 has a front end face 20A facing the end face 10A of the first electrode 10 in the first direction DR1, a side surface 20B facing the guide portion 30 in the second direction DR2, and a rear end face 20C (see Figure 2) located on the opposite side from the front end face 20A. The second electrode 20 is provided with a tapered hole 20H that opens into the front end face 20A. The diameter of the tapered hole 20H decreases as it moves away from the front end face 20A. The axis of the tapered hole 20H coincides with the central axis CA.

[0019] The front end surface 20A is positioned closer to the first electrode 10 than the side surface 20B. Preferably, the front end surface 20A is a convex surface that protrudes toward the first electrode 10 as it approaches the hole axis (central axis CA) of the tapered hole 20H in the second direction DR2. The front end surface 20A may also be a plane perpendicular to the central axis CA.

[0020] The front end surface 20A of the second electrode 20 in the first position faces the end surface 10A of the first electrode 10 with a gap between them. The front end surface 20A of the second electrode 20 in the second position is in contact with the end surface 10A of the first electrode 10.

[0021] The second electrode 20 is further provided with a through hole 20I that communicates with the tapered hole 20H. The minimum diameter of the through hole 20I is greater than the minimum diameter of the tapered hole 20H. The axis of the through hole 20I coincides with the central axis CA.

[0022] The guide portion 30 has a guide surface 30A that extends along the first direction DR1. The guide surface 30A is, for example, an inner diameter surface that is continuous in the circumferential direction with respect to the central axis CA. In the second direction DR2, the guide surface 30A faces the side surface 20B of the second electrode 20.

[0023] The holding portion 41 is capable of holding the second electrode 20, which is spaced apart from the first electrode 10, against the guide portion 30. The holding portion 41 is provided to slide against the guide surface 30A of the guide portion 30 when the second electrode 20 is pressed by the first drive portion 50 and moves in the first direction DR1.

[0024] The first drive unit 50 can press and move the second electrode 20, which is held by the holding unit 41, toward the first electrode 10.

[0025] The discharge induction mechanism 70 induces a discharge between the first electrode 10 and the second electrode 20. The discharge induction mechanism 70 includes a trigger electrode 71. The trigger electrode 71 is movable in the first direction DR1 together with the second electrode 20.

[0026] The trigger electrode 71 is electrically insulated from the second electrode 20. The trigger electrode 71 has a tip portion 71A and a rear end portion located opposite to the tip portion 71A in the first direction DR1. The tip portion 71A is the front end portion of the trigger electrode 71 that is positioned closest to the first electrode 10 in the first direction DR1. The tip portion 71A is located inside the tapered hole 20H of the second electrode 20. The tip portion 71A does not protrude toward the first electrode 10 beyond the front end surface 20A of the second electrode 20. The end surface of the tip portion 71A is, for example, on the same plane as the front end surface 20A of the second electrode 20.

[0027] The discharge induction mechanism 70 further includes a voltage generating element 73. The voltage generating element 73 is movable in the first direction DR1 together with the second electrode 20 and the trigger electrode 71. The voltage generating element 73 outputs a trigger voltage to the trigger electrode 71. Preferably, the voltage generating element 73 does not output the trigger voltage in the first state shown in Figure 1, but is configured to output the trigger voltage when it reaches the operating state shown in Figure 4.

[0028] The voltage generating element 73 has a first end 73A that is electrically connected to the rear end of the trigger electrode 71, and a second end 73B that is located on the opposite side from the first end 73A in the first direction DR1. The voltage generating element 73 is provided to generate a potential difference between the first end 73A and the second end 73B. The first end 73A is electrically insulated from the second electrode 20. The second end 73B is electrically connected to the second electrode 20. The second end 73B is electrically connected to the second electrode 20, for example, via connection parts 74 and 75, which will be described later.

[0029] The voltage generating element 73 is positioned on the opposite side of the trigger electrode 71 from the first electrode 10 in the first direction DR1. Viewed from the first direction DR1, the voltage generating element 73 is positioned so as to overlap with the trigger electrode 71.

[0030] The voltage generating element 73 is, for example, a piezoelectric element. The voltage generating element 73 is provided to generate a potential difference between the first end 73A and 73B when mechanical energy (non-electrical energy) is applied. The first drive unit 50 is provided to press the second electrode 20 and the voltage generating element 73 simultaneously.

[0031] The voltage generating element 73 may be configured to generate a potential difference between the first end 73A and 73B when non-electrical energy such as thermal energy or magnetic energy is applied. The voltage generating element 73 may also have an induction coil.

[0032] The discharge induction mechanism 70 may further include an insulating member 72 and connecting parts 74 and 75.

[0033] The insulating member 72 electrically insulates the trigger electrode 71 and the first end portion 73A of the voltage generating element 73 from the second electrode 20. The insulating member 72 has a front portion located within the through hole 20I of the second electrode 20 and a rear portion located on the rear end surface 20C of the second electrode 20.

[0034] The insulating member 72 is provided with a first through-hole 72H and a second through-hole 72I that communicates with the first through-hole 72H. The first through-hole 72H penetrates the front portion of the insulating member 72. The second through-hole 72I penetrates the rear portion of the insulating member 72. A trigger electrode 71 is inserted through the first through-hole 72H. A voltage generating element 73 is housed in the second through-hole 72I.

[0035] The connecting portions 74 and 75 electrically connect the second end portion 73B of the voltage generating element 73 to the second electrode 20. The connecting portions 74 and 75 have a conductive plate 74 and a conductive column 75.

[0036] The conductive plate 74 is in contact with the second end portion 73B of the voltage generating element 73. The conductive plate 74 is positioned, for example, in the first direction DR1, on the side opposite to the trigger electrode 71 relative to the voltage generating element 73. The conductive plate 74 is positioned on the rear end surface of the rear portion of the insulating member 72. Viewed from the first direction DR1, the conductive plate 74 has a central portion that overlaps with the voltage generating element 73 and an outer portion that is located outside the central portion in the second direction DR2 and overlaps with the insulating member 72.

[0037] The conductive column 75 electrically connects the outer portion of the conductive plate 74 to the second electrode 20. The connecting portion 74, 75 may have at least one conductive column 75, but preferably has multiple conductive columns 75. The multiple conductive columns 75 are arranged at intervals from each other in the circumferential direction with respect to the central axis CA, surrounding the trigger electrode 71 and the voltage generating element 73.

[0038] The connecting parts 74 and 75 may be provided to integrally fix the trigger electrode 71, the insulating member 72, and the voltage generating element 73 to the second electrode 20. The conductive column 75 may be a fixing member that can be fixed to the second electrode 20. The conductive column 75 is, for example, a screw. The second electrode 20, the trigger electrode 71 of the discharge induction mechanism 70, the insulating member 72, the voltage generating element 73, and the connecting parts 74 and 75 are all movable together in the first direction DR1. The first drive unit 50 may be provided to press the central portion of the conductive plate 74.

[0039] As shown in Figure 2, the tapered hole 20H has a first open end 20H1 that opens to the front end surface 20A and a second open end 20H2 located on the opposite side from the first open end 20H1.

[0040] The first through hole 72H has a third open end 72H1 that communicates with the second open end 20H2 of the tapered hole 20H. In the radial direction (second direction DR2) with respect to the hole axis of the tapered hole 20H, the third open end 72H1 of the first through hole 72H is positioned inward from the second open end 20H2 of the tapered hole 20H.

[0041] As shown in Figure 3, the distance between the tip 71A of the trigger electrode 71 and the second open end 20H2 of the tapered hole 20H is the minimum distance D1 between the tip 71A of the trigger electrode 71 and the second electrode 20. The minimum distance D1 between the tip 71A of the trigger electrode 71 and the second electrode 20 is smaller than the shortest distance L between the first electrode 10 and the second electrode 20 at the second position.

[0042] The front portion of the insulating member 72 has a front end surface 72A. The first through hole 72H opens into the front end surface 72A of the insulating member 72. The front end surface 72A extends inward beyond the second opening end 20H2 of the tapered hole 20H. The rear portion of the insulating member 72 has a side surface 72B (see Figure 1) that faces the guide surface 30A of the guide portion 30 and the second direction DR2. The rear portion of the insulating member 72 is provided with a recess 72J that is recessed relative to the rear end surface of the insulating member 72. The conductive plate 74 and a part of the conductive column 75 are arranged within the recess 72J.

[0043] Hereinafter, the details of a specific example of the high-speed inserter 101 will be described. <Specific Example of High-Speed Inserter> The first electrode 10 has a bottom portion 11 and a first protrusion 12. The bottom portion 11 is exposed to the outside in the high-speed inserter 101. The bottom portion 11 is provided as the first lid portion 2. The bottom portion 11 has a central portion and an outer edge portion surrounding the central portion when viewed from the first direction DR1. The outer edge portion of the bottom portion 11 is connected to one open end of the first pipe portion 3 in the first direction DR1. The first protrusion 12 protrudes from the central portion of the bottom portion 11 toward the second electrode 20 side. The first protrusion 12 has the end face 10A. The end face 10A is, for example, a plane orthogonal to the first direction DR1. Note that the end face 10A may be a curved surface. The end face 10A may be a convex surface.

[0044] In the first electrode 10, the first protrusion 12 is provided as, for example, a member different from the bottom portion 11. Note that the first protrusion 12 may be provided as the same member as the bottom portion 11.

[0045] The second electrode 20 is movable in the first direction DR1 toward the first electrode 10. The second electrode 20 has a main body portion 21 and a second protrusion 22. The main body portion 21 is disposed on the side opposite to the first electrode 10 with respect to the second protrusion 22 in the first direction DR1. The main body portion 21 has a central portion and an outer edge portion surrounding the central portion when viewed from the first direction DR1. The outer edge portion of the main body portion 21 is connected to one open end of the first pipe portion 3 in the first direction DR1. The second protrusion 22 protrudes from the central portion of the main body portion 21 toward the first electrode 10 side. The outer diameter of the second protrusion 22 in the second direction DR2 is smaller than the outer diameter of the main body portion 21 in the second direction DR2.

[0046] The second protrusion 22 has a front end face 20A facing the first electrode 10 side in the first direction DR1. The outer edge portion of the main body portion 21 has a side face 20B facing outward in the second direction DR2. The side face 20B faces the guide surface 30A of the guide portion 30 in the second direction DR2 at each of the first position and the second position. From a different perspective, the guide surface 30A of the guide portion 30 guides the second electrode 20 and the holding portion 41 when the second electrode 20 moves from the first position to the second position.

[0047] On a side surface 20B of the second electrode 20, a first groove portion 21G is provided. The first groove portion 21G is recessed inward from the side surface 20B in the second direction DR2 and extends along the circumferential direction with respect to the central axis CA. The first groove portion 21G is, for example, an annular groove continuous in the circumferential direction with respect to the central axis CA. The first groove portion 21G is provided so as to accommodate a part of the holding portion 41.

[0048] The first groove portion 21G has a pair of inner wall surfaces facing each other in the first direction DR1 and a bottom surface connecting the inner peripheral ends of the pair of inner wall surfaces. The bottom surface of the first groove portion 21G faces the guide surface 30A of the guide portion 30 in the second direction DR2.

[0049] The length of the guide surface 30A of the guide portion 30 in the first direction DR1 is not less than the moving distance between the first position and the second position of the second electrode 20. The distance in the second direction DR2 between the side surface 20B of the second electrode 20 and the guide surface 30A of the guide portion 30 is shorter than the distance in the second direction DR2 between the side surface of the first electrode 10 and the inner peripheral surface of the first tube portion 3.

[0050] Preferably, in the first state, the shortest distance L between the first electrode 10 and the second electrode 20 is longer than the shortest distance between the first electrode 10 and the guide portion 30.

[0051] The holding portion 41 is an elastic body that can be elastically deformed in the second direction DR2. The holding portion 41 is, for example, an annular elastic body. The holding portion 41 is in contact with each of the bottom surface of the first groove portion 21G and the guide surface 30A. The holding portion 41 is sandwiched between the bottom surface of the first groove portion 21G and the guide surface 30A and is compressed in the second direction DR2. The holding portion 41 applies a reaction force (elastic force) to each of the bottom surface of the first groove portion 21G and the guide surface 3OA.

[0052] The holding portion 41 is in contact with at least one of the pair of inner wall surfaces of the first groove portion 21G. The holding portion 41 is, for example, in contact with each of the pair of inner wall surfaces of the first groove portion 21G.

[0053] The retaining portion 41 is, for example, a spring coil. The retaining portion 41 is bent into an annular shape so as to surround the bottom surface of the first groove portion 21G of the second electrode 20 when viewed from the first direction DR1. One end of the retaining portion 41 in the circumferential direction is connected to, for example, the other end of the retaining portion 41 in the circumferential direction. The retaining portion 41 is compressed in the second direction DR2.

[0054] The first drive unit 50 is, for example, a cylinder. The first drive unit 50 includes, for example, a cylinder tube 51, a rod 52, and a linear motion mechanism 53. The cylinder tube 51 is fixed to the second cover 5. The rod 52 is movable relative to the cylinder tube 51 in a first direction DR1. The rod 52 can press the second electrode 20 toward the first electrode 10. The linear motion mechanism 53 includes, for example, a motor and a ball screw, and moves the rod 52 in the first direction DR1 according to the rotation of the motor.

[0055] The rod 52 is in contact with the conductive plate 74 in the first state, for example. The rod 52 may be separated from the conductive plate 74 in the first state. The rod 52 presses the second electrode 20 toward the first electrode 10 in the second state, for example. In the second state, the second electrode 20, which is in contact with the first electrode 10, is held by, for example, the first drive unit 50 and the spring 60, which will be described later.

[0056] In the second state, the rod 52 may be separated from the conductive plate 74. The second electrode 20, which is in contact with the first electrode 10, may be held only by the spring 60, which will be described later.

[0057] The high-speed electrode inlet 101 may further include a spring 60. The spring 60 biases the second electrode 20, which is at least spaced apart from the first electrode 10, toward the first electrode 10. The spring 60 biases the second electrode 20 toward the first electrode 10, at least in the first state. Preferably, the spring 60 can bias the second electrode 20, which is in contact with the first electrode 10, toward the first electrode 10. Preferably, the spring 60 biases the second electrode 20 toward the first electrode 10 in the first and second states.

[0058] The spring 60 is positioned in the first direction DR1 on the opposite side of the second electrode 20 from the first electrode 10. The spring 60 is positioned in the first direction DR1 on the opposite side of the insulating member 72 from the first electrode 10. One end of the spring 60 in the first direction DR1 is connected to the rear portion of the insulating member 72. The other end of the spring 60 in the first direction DR1 is positioned in the recess 72J of the insulating member 72. The other end of the spring 60 in the first direction DR1 is connected to, for example, the second cover portion 5.

[0059] The spring 60 is expandable and contractible in a first direction DR1. The natural length of the spring 60 in the first direction DR1 is shorter than the distance in the first direction DR1 between the second electrode 20 and the second cover 5 in the first state. Preferably, the natural length of the spring 60 in the first direction DR1 is shorter than the distance in the first direction DR1 between the second electrode 20 and the second cover 5 in the second state.

[0060] The spring 60 is spaced apart from the conductive plate 74 and the first drive unit 50. The inner diameter of the spring 60 in the second direction DR2 is greater than the maximum width of the conductive plate 74 in the second direction DR2 and the maximum width of the first drive unit 50 in the second direction DR2. The spring 60 is arranged, for example, to surround the conductive plate 74 and the first drive unit 50 in the second direction DR2. The outer diameter of the spring 60 in the second direction DR2 is smaller than the outer diameter of the second electrode 20 in the second direction DR2. The outer diameter of the spring 60 in the second direction DR2 is smaller than the inner diameter of the recess 72J in the second direction DR2.

[0061] As shown in Figure 1, the high-speed feeder 101 includes, for example, a container 1. The container 1 has, for example, a first lid 2, a first tube 3, a second tube 4, a second lid 5, and a third tube 6. The first lid 2 and the second tube 4 are electrically conductive. The first tube 3, the second lid 5, and the third tube 6 are electrically insulating.

[0062] For example, the bottom portion 11 of the first electrode 10 forms the first lid portion 2. The first electrode 10 is one of the two main electrodes (first main electrode) of the high-speed switch 101 which is electrically connected in parallel to one module circuit.

[0063] For example, at least a part of the guide section 30 forms the second pipe section 4. The guide section 30 has, for example, a portion made up of the second pipe section 4 and a portion that is electrically connected to the second pipe section 4 and fitted to the inner diameter surface of the third pipe section 6. In the high-speed feeder 101, the guide section 30 forms the other main electrode (second main electrode) of the two main electrodes of the high-speed feeder 101 that are electrically connected in parallel to one module circuit.

[0064] In the electrical device equipped with the high-speed input device 101, the first main electrode is connected to one of the input terminals and output terminals of the module circuit. The second main electrode is connected to the other of the input terminals and output terminals of the module circuit.

[0065] The first pipe section 3, the second pipe section 4, and the third pipe section 6 extend along a first direction DR1 and are arranged side by side in the first direction DR1. One open end of the first pipe section 3 in the first direction DR1 is closed by the first lid section 2. The other open end of the first pipe section 3 in the first direction DR1 is connected to one open end of the second pipe section 4 in the first direction DR1. The other open end of the second pipe section 4 in the first direction DR1 is connected to one open end of the third pipe section 6 in the first direction DR1. The other open end of the third pipe section 6 in the first direction DR1 is closed by the second lid section 5. Inside the container 1, a space is formed surrounded by the first lid section 2, the first pipe section 3, the second pipe section 4, the third pipe section 6, and the second lid section 5. Furthermore, of the first lid portion 2, the first pipe portion 3, the second pipe portion 4, the second lid portion 5, and the third pipe portion 6, two or more adjacent members may be provided integrally as the same member. Also, at least one of the first lid portion 2, the first pipe portion 3, the second pipe portion 4, the second lid portion 5, and the third pipe portion 6 may be provided as an assembly of multiple members.

[0066] The internal space of container 1 is filled with an insulating gas, such as air or sulfur hexafluoride. The internal space of container 1 may also be a vacuum.

[0067] The high-speed switch 101 is maintained in the first state shown in Figure 1 until an abnormality in the module circuit is detected and the switching operation is initiated.

[0068] In the first state, the shortest distance L in the first direction DR1 between the first electrode 10 and the second electrode 20 held by the holding part 41 is greater than or equal to the insulation distance between the first electrode 10 and the second electrode 20. In the first state, the module circuit electrically connected in parallel to the high-speed switch 101 is operating normally. In the first state, the voltage applied to the module circuit electrically connected in parallel to the high-speed switch 101 is applied between the first electrode 10 and the second electrode 20. In the first state, since the first electrode 10 and the second electrode 20 are electrically insulated, a normal current flows through the module circuit.

[0069] In the first state, the discharge induction mechanism 70 does not induce a discharge between the first electrode 10 and the second electrode 20. The voltage generating element 73 does not output a trigger voltage.

[0070] In the first state, the retaining portion 41 is compressed in the second direction DR2. In the first state, the frictional force generated between the retaining portion 41 and the guide portion 30 is greater than the biasing force applied to the retaining portion 41 by the charged spring 60. In the first state, the retaining portion 41 prevents the second electrode 20 from moving toward the first electrode 10 against the biasing force of the spring 60.

[0071] In the high-speed switch 101, when an abnormality in the module circuit is detected, a switching command signal is input to the first drive unit 50. The first drive unit 50 presses the second electrode 20, the voltage generating element 73, and the holding part 41 toward the first electrode 10 via the conductive plate 74. As a result, the second electrode 20, the voltage generating element 73, and the holding part 41 begin to move toward the first electrode 10 in the first direction DR1. A potential difference is generated between the first end 73A and the second end 73B of the voltage generating element 73. Since the trigger electrode 71 is electrically connected to the first end 73A and the second electrode 20 is electrically connected to the second end 73B, a potential difference is also generated between the trigger electrode 71 and the second electrode 20.

[0072] As shown in Figure 4, before the second electrode 20 reaches the second position, the voltage generating element 73 generates a trigger voltage between the first end 73A and the second end 73B. The trigger voltage is greater than the dielectric breakdown voltage of the medium between the trigger electrode 71 and the second electrode 20. The voltage generating element 73 is configured, for example, to generate the trigger voltage immediately after the second electrode 20 starts moving. The voltage generating element 73 may also be configured to generate the trigger voltage at the start of the movement of the second electrode 20. The trigger voltage is applied between the trigger electrode 71 and the second electrode 20. A trigger discharge occurs between the tip 71A of the trigger electrode 71 and the second electrode 20.

[0073] Even in the operating state shown in Figure 4, the distance between the tip 71A of the trigger electrode 71 and the second electrode 20 is smaller than the distance between the first electrode 10 and the second electrode 20.

[0074] A trigger discharge generates charged particles between the first electrode 10 and the second electrode 20. These charged particles reduce the dielectric breakdown voltage of the medium between the first electrode 10 and the second electrode 20. The dielectric breakdown voltage of the medium between the first electrode 10 and the second electrode 20 becomes smaller than the voltage applied between the first electrode 10 and the second electrode 20. As a result, a DC discharge occurs between the first electrode 10 and the second electrode 20, as shown in Figure 4, causing the second electrode 20 to conduct to the first electrode 10. Consequently, before the second electrode 20 contacts the first electrode 10, the fault current path switches from the module circuit electrically connected in parallel to the fast switch 101 to the fast switch 101. The module circuit electrically connected in parallel to the fast switch 101 is bypassed and disabled.

[0075] The voltage generating element 73 may be configured to generate a trigger voltage immediately after the second electrode 20 starts moving. Alternatively, the voltage generating element 73 may be configured to generate a trigger voltage when the second electrode 20 starts moving from the first position.

[0076] The second electrode 20 is further pressed toward the first electrode 10 by the first drive unit 50 and the spring 60. As a result, as shown in Figure 5, the second electrode 20 comes into contact with the first electrode 10. The second electrode 20 conducts to the first electrode 10 without discharge. The fault current continues to flow through the fast switch 101. The second state in which the second electrode 20 is in contact with the first electrode 10 can be maintained by at least one of the first drive unit 50 and the spring 60. In this way, the fast switch 101 can act as a path for the fault current while the second electrode 20 is in contact with the first electrode 10, after the operating state shown in Figure 4.

[0077] In the high-speed electrode dispenser 101, the second electrode 20 is provided with a tapered hole 20H that opens at the front end surface 20A and whose diameter decreases as it moves away from the front end surface 20A. The trigger electrode 71 has a tip portion 71A located inside the tapered hole 20H. Therefore, in the high-speed electrode dispenser 101, the narrowest portion between the trigger electrode 71 and the second electrode 20 can be formed between the trigger electrode 71 and the second opening end 20H2 of the tapered hole 20H. The distance between the trigger electrode 71 and the second opening end 20H2 of the tapered hole 20H can be smaller than the minimum distance between the trigger electrode and the fixed electrode described in Patent Document 1. Therefore, even if the voltage applied between the trigger electrode 71 and the second opening end 20H2 of the tapered hole 20H is small, a trigger discharge can be stably generated between the trigger electrode 71 and the second electrode 20, and as a result, a discharge can be stably generated between the first electrode 10 and the second electrode 20.

[0078] In the high-speed switch 101, since the trigger electrode 71 is movable together with the second electrode 20, the second electrode 20 can be quickly brought into contact with the first electrode 10 after the second electrode 20 and the first electrode 10 are short-circuited due to a trigger discharge. Therefore, the state in which the second electrode 20 and the first electrode 10 are short-circuited can be maintained for a long time while preventing wear of the trigger electrode 71. Such a high-speed switch 101 is suitable for power conversion devices.

[0079] In the high-speed discharger 101, the front end surface 20A is a convex surface that protrudes toward the first electrode 10 side as it approaches the hole axis (central axis CA) in the radial direction (second direction DR2) with respect to the hole axis of the tapered hole 20H. In this way, dielectric breakdown caused by trigger discharge can be made to occur near the tapered hole 20H, and dielectric breakdown can be prevented from occurring in unintended locations. For example, dielectric breakdown can be prevented from occurring at the outer edge of the front end surface 20A.

[0080] In the high-speed feeder 101, in the radial direction with respect to the hole axis of the tapered hole 20H, the third opening end 72H1 of the first through hole 72H of the insulating member 72 is positioned inward from the second opening end 20H2 of the tapered hole 20H. From a different perspective, the front end surface 72A of the insulating member 72 extends inward from the second opening end 20H2 of the tapered hole 20H. Such an insulating member 72 can prevent the trigger electrode 71 inserted through the first through hole 72H from making electrical contact with the second electrode 20.

[0081] In the high-speed switch 101, the trigger electrode 71, insulating member 72, and voltage generating element 73 of the discharge induction mechanism 70 may be integrally fixed to the second electrode 20 by connection parts 74 and 75. The trigger electrode 71, insulating member 72, and voltage generating element 73 can move in the first direction DR1 as an integral part of the second electrode 20 without a complex structure. Furthermore, a high-voltage circuit for outputting a trigger voltage to the trigger electrode 71, a control circuit for controlling the high-voltage circuit, and wiring to electrically connect these circuits to the trigger electrode 71 are unnecessary.

[0082] In the high-speed switch 101, the voltage generating element 73 may be a piezoelectric element. In this case, the first drive unit 50 may be provided to press the second electrode 20 and the voltage generating element 73 simultaneously. This eliminates the need for a high-voltage circuit for generating the trigger voltage and a control circuit for controlling the high-voltage circuit.

[0083] In the high-speed feeder 101, the holding portion 41 may be provided to slide with the guide portion 30 when the second electrode 20, which is pressed toward the first electrode 10 by the first drive portion 50, moves in the first direction DR1.

[0084] When such a holding portion 41 is pressed in the first direction DR1 via the second electrode 20 by the first drive unit 50, it can no longer prevent the movement of the second electrode 20, and moves toward the first electrode 10 together with the second electrode 20, sliding against the guide portion 30. The direction of the pressing force applied to the second electrode 20 and the holding portion 41 in order to insert the second electrode 20 into the first electrode 10 is the same as the direction of movement of the second electrode 20. In such a high-speed feeder 101, the insertion operation of inserting the second electrode 20 into the first electrode 10 can be performed as a one-stage operation, so the insertion operation can be made faster compared to the conventional high-speed feeder described above.

[0085] The high-speed feeder 101 may further include a spring 60 that biases the second electrode 20 toward the first electrode 10. The holding unit 41 allows the second electrode 20 to move toward the first electrode 10 when the second electrode 20, which is biased by the spring 60, is pressed by the first drive unit 50.

[0086] In such a high-speed feeder 101, the pressing force of the first drive unit 50 and the biasing force of the spring 60 are applied to the second electrode 20 and the holding unit 41. Therefore, the feed speed (the speed of switching from the first state to the second state) can be increased compared to the case where only the pressing force of the first drive unit 50 is applied to the second electrode 20 and the holding unit 41.

[0087] In the high-speed electrode dispenser 101, the spring 60 may be able to bias the second electrode 20, which is in contact with the first electrode 10, toward the first electrode 10. As a result, the contact pressure between the second electrode 20 and the first electrode 10 is greater than when the spring 60 does not bias the second electrode 20 toward the first electrode 10. In such a high-speed electrode dispenser 101, the state in which the second electrode 20 is energized toward the first electrode 10 can be maintained more reliably.

[0088] The high-speed feeder 101 may include a container 1 in which an insulating space is formed inside. The first electrode 10 and the guide portion 30 constitute part of the container 1. The second electrode 20, the holding portion 41, and at least a part of the first drive portion 50 are arranged inside the container 1. In such a high-speed feeder 101, it is possible to prevent the second electrode 20 and the first electrode 10 from being electrically connected via a conductive gas present between the second electrode 20 and the first electrode 10 in the first position.

[0089] The holding portion 41 is positioned relative to the second electrode 20 and may slide relative to the guide portion 30 as the second electrode 20 moves. The holding portion 41 and the guide portion 30 can appropriately guide the second electrode 20 as it moves from the first position to the second position. Even when the second electrode 20 is in the second position, a frictional force may be generated between the holding portion 41 and the guide portion 30. This frictional force, along with the contact pressure from the spring 60, suppresses the movement of the second electrode 20 away from the first electrode 10.

[0090] In the high-speed feeder 101, the holding portion 41 may be conductive. Such a holding portion 41 can also serve as a connecting member that electrically connects the second electrode 20 and the guide portion 30, which acts as the second main electrode. Therefore, in the high-speed feeder 101, there is no need to provide a connecting member for electrically connecting the second electrode 20 and the guide portion 30, which acts as the second main electrode, separately from the holding portion 41, and the number of parts can be reduced compared to a high-speed feeder in which the connecting member is provided separately from the holding portion 41.

[0091] A first groove 21G may be provided on the side surface 20B of the second electrode 20. The retaining portion 41 is in contact with the guide surface 30A and the bottom surface of the first groove 21G, respectively. The first groove 21G can position the retaining portion 41 relative to the second electrode 20.

[0092] In the high-speed feeder 101, the holding portion 41 may be a spring coil. The holding portion 41 is bent into an annular shape so as to surround the second electrode 20 when viewed from the first direction DR1, and is compressed in the second direction DR2. The holding force of such a holding portion 41, that is, the reaction force applied to the bottom surface of the first groove portion 21G and the guide surface 30A by the holding portion 41, is relatively stable and easy to adjust. Therefore, it is also easy to adjust the balance between the holding force of the holding portion 41 and the biasing force of the spring 60. As a result, the feeding operation of the high-speed feeder 101 is more stable than that of conventional high-speed feeders. For example, compared to a high-speed feeder that uses a method in which a notch is made in the holding portion that is placed between the movable electrode and the container, and the movable electrode is fed into the fixed electrode by pressing the holding portion and cutting the holding portion in the notch, the feeding operation of the high-speed feeder 101 is more stable.

[0093] Embodiment 2. As shown in Figures 6 and 7, the high-speed feeder 102 according to Embodiment 2 has the same configuration and effects as Embodiment 1 unless otherwise specified. Therefore, the same reference numerals are used for components identical to those in Embodiment 1, and the descriptions are not repeated.

[0094] In the high-speed feeder 102, the tip portion 71A of the trigger electrode 71 is spaced further away from the first electrode 10 than the front end surface 20A.

[0095] The distance D2 in the first direction DR1 between the tip portion 71A of the trigger electrode 71 and the front end surface 20A of the second electrode 20 is, for example, shorter than the length of the portion in the first direction DR1 of the portion of the insulating member 72 that protrudes into the tapered hole 20H from the front end surface 72A. The distance D2 in the first direction DR1 between the tip portion 71A of the trigger electrode 71 and the front end surface 20A of the second electrode 20 is, for example, smaller than the distance D3 in the second direction DR2 between the tip portion 71A and the inner circumferential surface of the tapered hole 20H. The distance D2 in the first direction DR1 between the tip portion 71A of the trigger electrode 71 and the front end surface 20A of the second electrode 20 is, for example, larger than the minimum distance D1 between the tip portion 71A of the trigger electrode 71 and the second electrode 20.

[0096] In the high-speed switch 102, the tip portion 71A of the trigger electrode 71 is spaced further away from the first electrode 10 than the front end surface 20A, so the electric field at the tip portion 71A is mitigated by the front end surface 20A. Therefore, it is possible to prevent unintended discharge from occurring at the tip portion 71A.

[0097] Embodiment 3. As shown in Figures 8 to 10, the high-speed feeder 103 according to Embodiment 3 has the same configuration and effects as Embodiment 1 unless otherwise specified. Therefore, the same reference numerals are used for components identical to those in Embodiment 1, and the descriptions are not repeated.

[0098] The high-speed inlet 103 is equipped with a first electrode 120 in place of the first electrode 10. The first electrode 120 is movable toward the second electrode 20 in the first direction DR1. No discharge induction mechanism is provided on the side of the first electrode 120.

[0099] The high-speed feeder 103 further includes a second drive unit 150 capable of pressing the first electrode 120 toward the second electrode 20. Preferably, the high-speed feeder 103 includes a guide unit 130, a holding unit 141, and a spring 160 as components related to the movement of the first electrode 120. The guide unit 130, the holding unit 141, the second drive unit 150, and the spring 160 may have the same configuration as the guide unit 30, the holding unit 41, the first drive unit 50, and the spring 60.

[0100] In the high-speed feeder 103, the first electrode 120 and the second electrode 20 move closer to each other during the feeding operation, so the feeding speed can be increased even further compared to the high-speed feeder 101.

[0101] Embodiment 4. As shown in Figure 11, the power conversion device according to Embodiment 4 comprises a plurality of power control circuits 200. The plurality of power control circuits 200 are connected in series with each other. The power control circuit 200 comprises terminals A and B, a module circuit 210, and a high-speed switch 100.

[0102] Terminals A and B are connected to the higher-level system of the power converter (for example, the AC power system). The module circuit 210 has a switching element 211 and an electrical energy storage device 212. The switching element 211 is, for example, an insulated-gate bipolar transistor (IGBT) or a thyristor. The electrical energy storage device 212 is, for example, a capacitor.

[0103] The high-speed feeder 100 is one of the high-speed feeders 101 to 103. The high-speed feeder 100 is electrically connected in parallel to the module circuit 210. The fixed electrode (first main electrode) of the high-speed feeder 100 is connected to one of the input terminals and output terminals of the module circuit 210. The guide portion (second main electrode) of the high-speed feeder 100 is connected to the other of the input terminals and output terminals of the module circuit 210.

[0104] When the module circuit 210 is operating normally, current flows through the module circuit 210 and not through the high-speed switch 100. When the module circuit 210 fails, the high-speed switch 100 operates, and terminals A and B are short-circuited. The high-speed switch 100 performs the switching operation described above. As a result, in the power control circuit 200, current flows through the high-speed switch 100, bypassing the failed module circuit 210. Since the failed module circuit 210 can be excluded from the current path, it is possible to prevent the effects of the failed module circuit 210 from spreading to the other power control circuits 200 and their higher-level systems. Therefore, in the power converter according to this embodiment, the remaining power control circuits 200 and their higher-level systems can continue to operate without being affected by the failed module circuit 210. Furthermore, if the number of power control circuits 200 in the power converter is redundant, the power converter can continue normal operation.

[0105] Furthermore, when the module circuit 210 malfunctions, an arc may occur in the module circuit 210. If the arc persists for an extended period, the likelihood of damage to surrounding components of the module circuit 210, or even explosion and destruction, increases. In the power converter according to this embodiment, since the high-speed switch 100 operates at high speed, the arc generation time can be shortened, preventing damage to surrounding components and destruction accompanied by explosion. The power converter according to this embodiment has high explosion-proof performance.

[0106] Embodiment 5. Figure 12 is a single-line connection diagram showing an example of the secondary side of a transformer in the power receiving and distribution equipment 220 according to Embodiment 5. The power receiving and distribution equipment 220 distributes AC power supplied from the power transmission system to load-side circuits 228 such as elevators, air conditioners, and lighting.

[0107] As shown in Figure 12, the power receiving and distribution equipment 220 according to Embodiment 5 includes a transformer 221 and a plurality of switchgears 222, 223.

[0108] The transformer 221 steps down the high-voltage power received from the power transmission system. Multiple switchgears 222 are installed between the transformer 221 and the busbar 226. Each switchgear 222 includes a high-speed switch 100 and a circuit breaker 224. The high-speed switch 100 is one of the high-speed switch 101 to 103. One of the fixed electrode 10 and movable electrode 20 of the high-speed switch 100 is electrically connected to the receiving side electrode (one electrode connected to the power transmission system side) of the circuit breaker 224. The other of the fixed electrode 10 and movable electrode 20 of the high-speed switch 100 is electrically connected to the ground conductor.

[0109] The multiple switchgears 223 include switchgears 223 installed on the busbar and multiple switchgears 223 installed between the busbar 226 and each of the multiple load-side circuits 228. Each switchgear 223 does not include, for example, a high-speed switch 100.

[0110] When no arc faults (internal arc faults) such as ground faults or short circuits occur in any of the multiple switchgears 222 and multiple switchgears 223, the current flows through the circuit breaker 224 in switchgear 222 and not through the high-speed closer 100. When an arc fault occurs in any of the multiple switchgears 222, the high-speed closer 100 in the faulty switchgear 222 performs the above-described closing operation, the arc current flows through the high-speed closer 100, and the arc is extinguished. Furthermore, the faulty switchgear 222 and its downstream system are excluded from the current path of the power distribution equipment 220. When an arc fault occurs in any of the multiple switchgears 223, the high-speed closer 100 in the upstream system switchgear 222 of the faulty switchgear 223 performs the above-described closing operation, the arc current flows through the high-speed closer 100, and the arc is extinguished. Furthermore, the downstream systems of the switchgear 222 that was switched on (including the switchgear 223 where the fault occurred) are excluded from the current path of the power receiving and distribution equipment 220. As a result, the power receiving and distribution equipment 220 can prevent the effects of the faulty switchgears 222 and 223 from spreading to healthy current paths that do not include those switchgears 222 and 223, and can continue to operate the healthy current paths and the load-side circuits 228 that are supplied from those healthy current paths.

[0111] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope of the claims are intended to be included.

[0112] 1 Container, 2 First lid, 3 First tube, 4 Second tube, 5 Second lid, 6 Third tube, 10 First electrode, 10A End face, 11 Bottom, 12 First projection, 20 Second electrode, 20A Front end face, 20B Side, 20C Rear end face, 20H Tapered hole, 20H1 First opening end, 20H2 Second opening end, 20I Through hole, 21 Main body, 21G First groove, 22 Second projection, 30 Guide part, 30A Guide surface, 41 Holding part, 50 First drive part, 51 Cylinder tube, 52 Rod, 53 Linear motion mechanism, 60 Spring, 70 Discharge induction mechanism, 71 Trigger electrode, 71A Tip, 72 Insulating member, 72A Front end face, 72B Side, 72H First through hole, 72H1 Third open end, 72I Second through hole, 72J Recess, 73 Voltage generating element, 73A First end, 73B Second end, 74, 75 Connection part, 100, 101, 102, 103 High-speed switch, 120 First electrode, 130 Guide part, 141 Holding part, 150 Second drive part, 160 Spring, 200 Power control circuit, 201 Switching element, 202 Electrical energy storage unit, 210 Module circuit, 221 Transformer, 222, 223 Switchgear, 224 Circuit breaker, 226 Busbar, 228 Load side circuit.

Claims

1. A high-speed feeder comprising a first electrode and a second electrode movable in a first direction toward the first electrode, wherein the second electrode is movable from a first position spaced apart from the first electrode in the first direction to a second position in contact with the first electrode, and further comprising a discharge induction mechanism for inducing a discharge between the second electrode and the first electrode, wherein the discharge induction mechanism includes a trigger electrode movable together with the second electrode, the second electrode has an end face facing the first electrode in the first direction, the second electrode is provided with a tapered hole opening at the end face and decreasing in diameter as it moves away from the end face, and the trigger electrode has a tip portion located inside the tapered hole.

2. The high-speed feeder according to claim 1, wherein the end face is a convex surface that protrudes toward the first electrode side as it approaches the hole axis in the radial direction with respect to the hole axis of the tapered hole.

3. The high-speed feeder according to claim 1 or 2, wherein the tip of the trigger electrode is spaced further apart from the first electrode than the end face.

4. The high-speed feeder according to claim 3, wherein the distance in the first direction between the tip of the trigger electrode and the end face of the second electrode is shorter than the radial distance between the tip and the inner circumferential surface of the tapered hole with respect to the hole axis of the tapered hole.

5. The high-speed feeder according to any one of claims 1 to 4, wherein the tapered hole has a first open end that opens to the end face and a second open end located on the opposite side of the first open end, the discharge induction mechanism further includes an insulating member that electrically insulates the trigger electrode from the second electrode, the insulating member is provided with a first through hole through which the trigger electrode is inserted, the first through hole has a third open end that communicates with the second open end, and in the radial direction with respect to the hole axis of the tapered hole, the third open end of the first through hole is positioned inward from the second open end of the tapered hole.

6. The high-speed switch according to claim 5, wherein the discharge induction mechanism further includes a voltage generating element movable together with the second electrode, the insulating member further has a second through hole communicating with the first through hole and housing the voltage generating element, the voltage generating element has a first end connected to the trigger electrode and a second end located on the opposite side of the first end, and is provided to generate a potential difference between the first end and the second end, the discharge induction mechanism further includes a connection portion for electrically connecting the second electrode and the second end, and the trigger electrode, the insulating member, and the voltage generating element are integrally fixed to the second electrode by the connection portion.

7. The high-speed feeder according to claim 6, further comprising a first drive unit capable of pressing the second electrode from the first position toward the second position, wherein the voltage generating element is a piezoelectric element, and the first drive unit is provided to press the second electrode and the piezoelectric element simultaneously.

8. The high-speed feeder according to claim 7, further comprising a guide portion for guiding the movement of the second electrode in the first direction, and a holding portion capable of holding the second electrode in the first position relative to the guide portion, wherein the holding portion slides with at least one of the second electrode and the guide portion when the second electrode, which is pressed toward the first electrode by the first drive portion, moves in the first direction.

9. The high-speed feeder according to claim 8, further comprising a spring for biasing the second electrode toward the first electrode, wherein the holding portion allows the second electrode to move toward the first electrode when the second electrode, biased by the spring, is pressed by the first drive portion.

10. The high-speed feeder according to claim 9, wherein the first drive unit is connected to the connection unit, and the spring is spaced apart from the first drive unit and connected to the insulating member.

11. A high-speed feeder according to any one of claims 1 to 10, comprising a container having an insulating space formed inside, wherein the first electrode constitutes a part of the container, and the second electrode and the trigger electrode are arranged inside the container.

12. The high-speed feeder according to any one of claims 1 to 11, further comprising a second drive unit that is movable toward the second electrode in a first direction and capable of pressing the first electrode toward the second electrode.

13. A power converter comprising a high-speed switch according to any one of claims 1 to 12 and a module circuit, wherein the high-speed switch is electrically connected in parallel to the module circuit.

14. A power receiving and distribution system comprising a high-speed switch according to any one of claims 1 to 13, a circuit breaker, and a grounding conductor, wherein one of the first electrode and the second electrode of the high-speed switch is electrically connected to one electrode of the circuit breaker, and the other of the first electrode and the second electrode of the high-speed switch is electrically connected to the grounding conductor.

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