Electric device and method for manufacturing electric device

Abstract

To provide an electric device and a method for manufacturing the electric device, capable of suppressing degradation of insulating performance in an insulator.SOLUTION: An electric device comprises an electrical insulator, a pair of electrodes, and a movement restraining portion. The pair of electrodes are fixed to an upper surface of the electrical insulator and are spaced apart from each other in a first direction. The movement restraining portion is provided on the upper surface, disposed between the pair of electrodes, and restrains movement of conductive foreign matter on the upper surface.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to an electrical device and a method for manufacturing an electrical device.

Background Art

[0002] In electrical devices used for power generation, power transmission, power distribution, etc. in a power system, there are parts where a high voltage is applied. In order to insulate this high-voltage part from a grounding part or the like, an insulator is provided between them.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In an electrical device that is operated for a long period of time, there is a risk that the insulating performance of the insulator will deteriorate due to contaminants accumulating on the insulator. For this reason, it is preferable that the electrical device has a configuration in which contaminants are less likely to accumulate on the insulator.

[0005] The problem to be solved by the present invention is to provide an electrical device and a method for manufacturing an electrical device that suppress a decrease in insulating performance in an insulator.

Means for Solving the Problems

[0006] To achieve the above object, an electrical device according to an embodiment of the present invention includes an insulator, a pair of electrodes, and a movement suppression unit. The pair of electrodes are fixed to the upper surface of the insulator and are spaced apart from each other in a first direction. The movement suppression unit is provided on the upper surface, disposed between the pair of electrodes, and suppresses the movement of conductive foreign matter on the upper surface.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

[0008] (First Embodiment) Hereinafter, the electrical device 1 according to the first embodiment will be described in detail with reference to the accompanying drawings. The configurations of the embodiments described below, as well as the operations and results (effects) brought about by such configurations, are merely examples and are not limited to the following description. In this specification, ordinal numbers are used only for distinguishing parts and members and do not indicate order or priority.

[0009] Referring to FIG. 1, the structure of the electrical device 1 according to the first embodiment of the present invention will be described. FIG. 1 is a perspective view showing a part of the configuration of the electrical device 1 of the first embodiment. The electrical device 1 is, for example, an insulator in power transmission and distribution equipment installed in coastal areas. The electrical device 1 includes an insulating system provided with an insulator having a creepage surface between a pair of electrodes. A DC voltage is applied to the pair of electrodes. The pair of electrodes are provided isolated from each other for electrical insulation. Note that the structure of the electrical device 1 of the first embodiment is not limited to the example shown in FIG. 1.

[0010] In the following description, an X-axis Y-axis Z-axis orthogonal coordinate system is defined. The X-axis direction is the direction in which the pair of electrodes are separated. The Y-axis direction is the direction in which each of the pair of electrodes extends. The Z-axis direction is the height direction of the electrical device 1, the +Z direction is the upward direction, and the -Z direction is the downward direction. The X-axis direction is an example of the first direction. Note that the X-axis Y-axis Z-axis orthogonal coordinate system is a coordinate system used for convenience, and the embodiments of the present invention can also be applied to electrical devices to which this coordinate system is not applicable.

[0011] As shown in FIG. 1, the electrical device 1 includes an insulator 10, a high-voltage electrode 11a, a ground electrode 11b, and a movement suppression unit 12. The insulator 10 is a part having a creepage surface with insulating performance in the electrical device 1. The insulator 10 is provided at a part where a high voltage is present in the electrical device 1. The insulator 10 is formed in a substantially rectangular parallelepiped shape. The insulator 10 extends in the X-axis direction and the Y-axis direction. The insulator 10 has an upper surface 101, a lower surface 102, and side surfaces 103. The high-voltage electrode 11a and the ground electrode 11b are examples of a pair of electrodes.

[0012] The upper surface 101 faces upward (+Z direction). The upper surface 101 is, for example, a horizontal plane, but is not limited thereto, and the upper surface 101 may be slightly inclined with respect to the horizontal plane. The lower surface faces downward (-Z direction). The side surface 103 faces the -Y direction.

[0013] The high-voltage electrode 11a is a conductor through which high-voltage power exceeding 750 V flows. The high-voltage electrode 11a is fixed to the upper surface 101. The high-voltage electrode ily extends in the Y-axis direction.

[0014] The ground electrode 11b is a conductor that is grounded and has a potential of zero. The ground electrode 11b is fixed to the upper surface 101. The ground electrode 11b extends in the Y-axis direction. The high-voltage electrode 11a and the ground electrode 11b are spaced apart from each other in the X-axis direction and form different polarities. More specifically, the high-voltage electrode 11a forms the positive electrode, and the ground electrode 11b forms the negative electrode.

[0015] The movement suppression part 12 is provided on the upper surface 101. The movement suppression part 12 is disposed between the high-voltage electrode 11a and the ground electrode 11b. More specifically, the movement suppression part 12 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b. The position where the movement suppression part 12 is provided in the X-axis direction is not limited to the above, and the movement suppression part 12 may be provided, for example, at a position closer to the high-voltage electrode 11a than the ground electrode 11b. The movement suppression part 12 extends in the Y-axis direction.

[0016] A conductive foreign object 13 adheres to the upper surface 101 of the insulator 10. The conductive foreign object 13 is, for example, a liquid containing foreign substances (salt) derived from seawater and is a conductive object. The movement suppression part 12 is a part that suppresses the movement of the conductive foreign object 13 on the upper surface 101.

[0017] Generally, when power facilities such as power systems are installed in coastal areas, foreign substances derived from seawater may adhere to the surface of the insulators inside the facilities. If foreign substances derived from seawater adhere and accumulate on the surface of the insulator, the insulation performance of the insulator may deteriorate.

[0018] (Electric field of electrical equipment) Next, the electric field of the electrical equipment 1 will be described with reference to FIG. 2. Note that the electric fields of the electrical equipment 1A, 1B1, 1B2, and 1C described later are the same as that of the electrical equipment 1, so the description thereof will be omitted. Also, in FIG. 2, only the components necessary for the description are shown, and some components are omitted.

[0019] FIG. 2 is a side view showing the electric lines of force in a part of the configuration of the electrical device 1 according to the first embodiment. As shown in FIG. 2, the electrical device 1 receives an electrostatic force due to an electric field E1 generated by the electric power flowing through the high-voltage electrode 11a and the ground electrode 11b. The direction of the electric field E1 is from the high-voltage electrode 11a, which is the positive electrode, toward the ground electrode 11b, which is the negative electrode. On the straight line connecting the high-voltage electrode 11a and the ground electrode 11b, the direction of the electric field E1 substantially coincides with the +X direction.

[0020] The conductive foreign matter 13 adhering to the upper surface 101 of the insulator 10 receives an electrostatic force in the +X direction due to the electric field E1. When the conductive foreign matter 13 receives an electrostatic force greater than the static frictional force with respect to the upper surface 101, it gradually moves on the upper surface 101 in the direction of the electrostatic force (+X direction). Then, when the conductive foreign matter 13 reaches the ground electrode 11b, it adheres to the ground electrode 11b. By repeating the above-described steps, the conductive foreign matter 13 accumulates in the vicinity of the ground electrode 11b.

[0021] As described above, the upper surface 101 is, for example, a horizontal plane. For this reason, in a state where no DC voltage is applied to the high-voltage electrode 11a and the ground electrode b, the conductive foreign matter 13 adhering to the upper surface 101 does not move on the upper surface 101 according to the action of gravity and remains on the upper surface 101.

[0022] On the other hand, in a state where a DC voltage is applied to the high-voltage electrode 11a and the ground electrode 11b, an electric field E1 is formed at the periphery of the insulator 10. Generally, a conductive foreign matter present in an electric field receives a force from the positive high-voltage electrode toward the negative ground electrode due to the electrostatic force generated by the electric field. Then, when the sum of the horizontal component of the gravity received by the conductive foreign matter and the horizontal component of the electrostatic force is greater than the static frictional force on the surface of the insulator, the conductive foreign matter gradually moves on the surface of the insulator in the direction of the electric field from the high-voltage electrode toward the ground electrode. Then, the conductive foreign matter contacts the ground electrode and adheres to the ground electrode.

[0023] In this way, the conductive foreign matter is subjected to the electrostatic force of the electric field and moves on the surface of the insulator, and by repeating the process of adhering to the ground electrode, the conductive foreign matter accumulates near the ground electrode. When the conductive foreign matter accumulates near the ground electrode, there is a risk that the insulation performance of the insulator will deteriorate.

[0024] In the electrical device 1 of this embodiment, the surface free energy of the movement suppression portion 12 is higher than the surface free energy of the insulator 10. For this reason, the conductive foreign matter 13 that has moved in the +X direction on the upper surface 101 of the insulator 10 by the electrostatic force of the electric field and reached the movement suppression portion 12 is likely to be trapped by the movement suppression portion 12. Further, the conductive foreign matter 13 cannot escape from the movement suppression portion 12 unless kinetic energy exceeding the energy required to pull it off from the movement suppression portion 12 is applied. For this reason, in the electric field strength at which the conductive foreign matter 13 slowly moves on the upper surface 101 by the electrostatic force of the electric field E1, the electrical device 1 suppresses the conductive foreign matter 13 from moving on the upper surface 101.

[0025] In the above embodiment, the electrical device 1 includes an insulator 10, a pair of electrodes (a high-voltage electrode 11a and a ground electrode 11b), and a movement suppression portion 12. The pair of electrodes are fixed to the upper surface 101 of the insulator 10 and are spaced apart from each other in the X-axis direction. The movement suppression portion 12 is provided on the upper surface 101, disposed between the pair of electrodes, and suppresses the movement of the conductive foreign matter 13 on the upper surface 101.

[0026] Also, in the above-described embodiment, the surface free energy of the movement suppression portion 12 is higher than that of the insulator 10.

[0027] According to the above configuration, when the conductive foreign matter 13 adhering to the upper surface 101 moves in the +X direction by the electrostatic force of the electric field and reaches the movement suppression portion 12, it is trapped by the movement suppression portion 12. Further, the surface free energy of the movement suppression portion 12 is higher than the surface free energy of the insulator 10. For this reason, the conductive foreign matter 13 trapped by the movement suppression portion 12 is suppressed from being peeled off from the movement suppression portion 12. In this way, the electric device 1 can suppress the conductive foreign matter 13 from depositing on the ground electrode 11b by suppressing the conductive foreign matter 13 from moving on the upper surface 101, and thus can suppress a decrease in the insulation performance of the insulator 10.

[0028] (Modification 1) Next, Modification 1 of the first embodiment will be described with reference to FIG. 3. Note that the same components as those of the electric device 1 according to the first embodiment are denoted by the same reference numerals and the description thereof is omitted, and different components will be described below.

[0029] FIG. 3 is a perspective view showing a part of another configuration of the electric device 1 of the first embodiment. As shown in FIG. 3, in Modification 1 of the first embodiment, the electric device 1A includes four movement suppression portions 12A1, 12A2, 12A3, and 12A4. Each of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4 is provided on the upper surface 101. Each of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4 is provided at intervals in the X-axis direction.

[0030] Each of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4 extends in the Y-axis direction. Each of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4 has a length in the X-axis direction shorter than that of the movement suppression portion 12. The lengths of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4 in the X-axis direction are substantially equal. Further, the lengths of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4 in the Y-axis direction are substantially equal to the lengths of the high-voltage electrode 11a and the ground electrode 11b in the Y-axis direction.

[0031] The conductive foreign matter 13 adheres to the upper surface 101 between the movement suppression portion 12A1 and the high-voltage electrode 11a. In Modification 1, the conductive foreign matter 13 adhering to the upper surface 101 moves in the +X direction on the upper surface 101 by the electrostatic force of the electric field E1. However, when the conductive foreign matter 13 reaches the movement suppression portion 12A1, it is trapped by the movement suppression portion 12A1, and the movement of the conductive foreign matter 13 is suppressed. If the conductive foreign matter 13 is not trapped by the movement suppression portion 12A1, the conductive foreign matter 13 further moves in the +X direction by the electrostatic force of the electric field E1, reaches the movement suppression portion 12A2, is trapped by the movement suppression portion 12A2, and the movement of the conductive foreign matter 13 is suppressed. Thus, the movement of the conductive foreign matter 13 in the +X direction is suppressed by at least one of the four movement suppression portions 12A1, 12A2, 12A3, and 12A4.

[0032] Similarly, when the conductive foreign matter 13 adheres between the movement suppression portion 12A1 and the movement suppression portion 12A2, the movement in the +X direction is suppressed by at least one of the three movement suppression portions 12A2, 12A3, and 12A4.

[0033] That is, in the electrical device 1A in Modification 1, since the movement suppression portions for trapping the conductive foreign matter 13 are provided over a wider range on the upper surface 101 than in the first embodiment, the movement of the conductive foreign matter 13 on the upper surface 101 can be suppressed more effectively.

[0034] (Modification 2) Next, Modification 2 of the first embodiment will be described. In the electrical device 1 in Modification 2, the movement suppression portion 12 has a structure that can be detached from the upper surface 101 of the insulator 10. More specifically, the movement suppression portion 12 is detachably fixed to the upper surface 101 by, for example, a double-sided tape.

[0035] When the conductive foreign matter 13 is trapped by the movement suppression part 12 and accumulates on the movement suppression part 12, the area of the surface of the conductive foreign matter 13 moving on the upper surface 101 in contact with the movement suppression part 12 gradually decreases, and the performance of the movement suppression part 12 to trap the conductive foreign matter 13 deteriorates. However, in the second modification, when an operator inspects the electric device 1 or the like, the movement suppression part 12 on which the conductive foreign matter 13 accumulates is detached and replaced with another movement suppression part 12. Thereby, the electric device 1 can suppress the deterioration of the trapping performance of the movement suppression part 12 due to the accumulation of a large amount of the conductive foreign matter 13 on the movement suppression part 12.

[0036] (Second Embodiment) Next, the electric devices 1B1 and 1B2 according to the second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a perspective view showing a part of the configuration of the electric device 1B1 of the second embodiment. FIG. 5 is a perspective view showing another part of the configuration of the electric device 1B1 of the second embodiment.

[0037] First, the electric device 1B1 according to the second embodiment will be described. As shown in FIG. 4, in the electric device 1B1, the movement suppression part 12B1 has a convex part 121 protruding upward (+Z direction). The convex part 121 is provided on the upper surface 101. The convex part 121 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b. The position where the convex part 121 is provided in the X-axis direction is not limited to the above, and the convex part 121 may be provided, for example, at a position closer to the high-voltage electrode 11a than the ground electrode 11b.

[0038] The convex part 121 is formed in a substantially rectangular parallelepiped shape. The convex part 121 extends in the Y-axis direction. The length (width) of the convex part 121 in the X-axis direction is sufficiently large with respect to the length of the insulator 10 in the X-axis direction. The length of the convex part 121 in the Y-axis direction is substantially equal to the lengths of the high-voltage electrode 11a and the ground electrode 11b in the Y-axis direction. The length (height) of the convex part 121 in the Z-axis direction is sufficiently large with respect to the length of the conductive foreign matter 13 in the Z-axis direction.

[0039] The conductive foreign object 13 adheres to the upper surface 101 between the high-voltage electrode 11a and the convex portion 121. The conductive foreign object 13 may be in a solid state. In the electrical device 1B1 according to the second embodiment, the conductive foreign object 13 adhering to the upper surface 101 moves in the +X direction on the upper surface 101 by the electrostatic force of the electric field E1. However, when the conductive foreign object 13 reaches the convex portion 121, the conductive foreign object 13 comes into contact with the convex portion 121, and further movement in the +X direction is physically suppressed. That is, the electrical device 1B1 in the second embodiment can more reliably suppress the movement of the conductive foreign object 13 than the first embodiment.

[0040] Next, the electrical device 1B2 according to the second embodiment will be described. As shown in FIG. 5, in the electrical device 1B2, the movement suppression portion 12B2 has a concave portion 122 that is recessed downward (-Z direction). The concave portion 122 is provided on the upper surface 101. The concave portion 122 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b. The position where the concave portion 122 is provided in the X-axis direction is not limited to the above, and the concave portion 122 may be provided, for example, at a position closer to the high-voltage electrode 11a than the ground electrode 11b.

[0041] The concave portion 122 extends in the Y-axis direction. The length (width) of the concave portion 122 in the X-axis direction is sufficiently small with respect to the length of the insulator 10 in the X-axis direction. The length of the concave portion 122 in the Y-axis direction is substantially equal to the lengths of the high-voltage electrode 11a and the ground electrode 11b in the Y-axis direction. The length (depth with respect to the upper surface 101) of the concave portion 122 in the Z-axis direction is sufficiently long with respect to the length of the conductive foreign object 13 in the Z-axis direction.

[0042] The conductive foreign object 13 adheres to the upper surface 101 between the high-voltage electrode 11a and the concave portion 122. The conductive foreign object 13 may be in a solid state. In the electrical device 1B2 according to the second embodiment, the conductive foreign object 13 adhering to the upper surface 101 moves in the +X direction on the upper surface 101 by the electrostatic force of the electric field E1. However, when the conductive foreign object 13 reaches the concave portion 122, the conductive foreign object 13 physically drops into the concave portion 122 due to the action of gravity and is physically suppressed from further moving in the +X direction. That is, the electrical device 1B2 in the second embodiment can more reliably suppress the movement of the conductive foreign object 13 than the first embodiment.

[0043] In the above embodiments, the movement suppression portion 12 has at least one of a convex portion 121 protruding upward and a concave portion 122 recessed downward.

[0044] According to the above configuration, when the conductive foreign object 13 adhering between the high-voltage electrode 11a and the convex portion 121 on the upper surface 101 of the electrical device 1B1 reaches the convex portion 121 by moving in the +X direction on the upper surface 101 of the insulator 10 by the electrostatic force of the electric field E1, it contacts the convex portion 121. For this reason, the electrical device 1B1 physically suppresses the conductive foreign object 13 from moving in the +X direction from the convex portion 121 on the upper surface 101, thereby suppressing the conductive foreign object 13 from depositing on the ground electrode 11b, and thus suppressing a decrease in the insulation performance of the insulator 10.

[0045] Also, when the conductive foreign object 13 adhering between the high-voltage electrode 11a and the concave portion 122 on the upper surface 101 of the electrical device 1B2 reaches the concave portion 122 by moving in the +X direction on the upper surface 101 of the insulator 10 by the electrostatic force of the electric field E1, it drops into the concave portion 122. For this reason, the electrical device 1B2 physically suppresses the conductive foreign object 13 from moving in the +X direction from the concave portion 122 on the upper surface 101, thereby suppressing the conductive foreign object 13 from depositing on the ground electrode 11b, and thus suppressing a decrease in the insulation performance of the insulator 10.

[0046] (Third Embodiment) Next, the electrical device 1C according to the third embodiment will be described with reference to FIG. 6. FIG. 6 is a perspective view showing a part of the configuration of the electrical device 1C of the third embodiment. As shown in FIG. 6, in the electrical device 1C, the movement suppression unit 12C has a fine structure unit 124. The fine structure unit 124 is provided on the upper surface 101. The fine structure unit 124 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b. The position where the fine structure unit 124 is provided in the X-axis direction is not limited to the above, and the fine structure unit 124 may be provided, for example, at a position closer to the high-voltage electrode 11a than the ground electrode 11b.

[0047] The fine structure unit 124 extends in the Y-axis direction. The length (width) of the fine structure unit 124 in the X-axis direction is sufficiently small with respect to the length of the insulator 10 in the X-axis direction. The length of the fine structure unit 124 in the Y-axis direction is substantially equal to the lengths of the high-voltage electrode 11a and the ground electrode 11b in the Y-axis direction. The fine structure unit 124 is formed with a recess that slightly depresses in the -Z direction with respect to the upper surface 101 and extends in the Y-axis direction, and a plurality of recesses are alternately arranged in the X-axis direction. The length of the fine structure unit 124 in the Z-axis direction (depth with respect to the upper surface 101) is sufficiently short with respect to the length (thickness) of the insulator 10 in the Z-axis direction. The fine structure unit 124 guides the conductive foreign matter 13 moving on the upper surface 101 in the Y-axis direction. The fine structure unit 124 may guide the conductive foreign matter 13 in a direction oblique to the X-axis direction and the Y-axis direction.

[0048] The conductive foreign matter 13 adheres to the upper surface 101 between the high-voltage electrode 11a and the fine structure unit 124. In the electrical device 1C according to the third embodiment, the conductive foreign matter 13 adhering to the upper surface 101 moves in the +X direction on the upper surface 101 by the electrostatic force of the electric field E1. However, when the conductive foreign matter 13 reaches the fine structure unit 124, the conductive foreign matter 13 falls into the recess of the fine structure unit 124 by the action of gravity, and is further guided in the Y-axis direction by capillary action and discharged from the end of the upper surface 101 in the Y-axis direction to the outside of the upper surface 101.

[0049] That is, the electrical device 1C in the third embodiment guides the conductive foreign matter 13 adhering to the upper surface 101 by the fine structure portion 124 in the Y-axis direction different from the +X direction which is the direction of the electric field E1, and discharges it to the outside of the upper surface 101, thereby suppressing the deposition of the conductive foreign matter 13 on the ground electrode 11b, and thus suppressing the deterioration of the insulation performance of the insulator 10.

[0050] In the above embodiment, the movement suppression portion 12 guides the conductive foreign matter 13 in a direction intersecting the X-axis direction.

[0051] According to the above configuration, the electrical device 1C can suppress the deterioration of the insulation performance of the insulator 10 due to the deposition of the conductive foreign matter 13 on the ground electrode 11b by discharging the conductive foreign matter 13 adhering to the upper surface 101 to the outside of the upper surface 101.

[0052] (Fourth Embodiment) Next, the electrical devices 1D1 and 1D2 according to the fourth embodiment will be described with reference to FIGS. 7 and 8. FIG. 7 is a perspective view showing a part of the configuration of the electrical device 1D1 of the fourth embodiment. FIG. 8 is a perspective view showing another part of the configuration of the electrical device 1D1 of the fourth embodiment.

[0053] First, the electrical device 1D1 according to the fourth embodiment will be described. As shown in FIG. 7, in the electrical device 1D1, an electrode groove 104 is provided in the insulator 10D. The electrode groove 104 is formed by being recessed in the +X direction from the lower surface 102. The electrode groove 104 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b. The position where the electrode groove 104 is provided in the X-axis direction is not limited to the above, and the electrode groove 104 may be provided, for example, at a position closer to the high-voltage electrode 11a than the ground electrode 11b. The electrode groove 104 extends in the Y-axis direction. The length (width) of the electrode groove 104 in the X-axis direction is longer than the length (width) of the movement suppression portion 12 in the X-axis direction. The length of the electrode groove 104 in the Y-axis direction is substantially equal to the lengths of the high-voltage electrode 11a and the ground electrode 1bb in the Y-axis direction. The length (thickness) of the electrode groove 104 in the Z-axis direction is shorter than the length (thickness) of the insulator 10D in the Z-axis direction.

[0054] The electric device 1D1 includes an embedded electrode 14. The embedded electrode 14 forms, for example, a negative electrode. The embedded electrode 14 is inserted into the electrode groove 104 of the insulator 10D1 and fixed to the insulator 10D, for example, by adhesion. The embedded electrode 14 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b. The position where the embedded electrode 14 is provided in the X-axis direction is not limited to the above, and the embedded electrode 14 may be provided, for example, at a position closer to the high-voltage electrode 11a than the ground electrode 11b. The embedded electrode 14 extends in the Y-axis direction. The lengths of the embedded electrode 14 in the X-axis, Y-axis, and Z-axis directions are substantially equal to the lengths of the electrode groove 104 in the X-axis, Y-axis, and Z-axis directions.

[0055] Next, the electric device 1D2 according to the fourth embodiment will be described. As shown in FIG. 8, the electric device 1D2 includes a back electrode 15. The back electrode 15 forms, for example, a negative electrode. The back electrode 15 is fixed to the lower surface 102, for example, by adhesion. The back electrode 15 extends in the X-axis direction and the Y-axis direction. The lengths of the back electrode 15 in the X-axis direction and the Y-axis direction are substantially equal to the lengths of the insulator 10 in the X-axis direction and the Y-axis direction. That is, the back electrode 15 is fixed to the lower surface 102 of the insulator 10 over the entire insulator 10. The length of the back electrode 15 in the Z-axis direction (the thickness of the back electrode 15) is shorter than the length of the insulator 10 in the Z-axis direction (the thickness). The embedded electrode 14 and the back electrode 15 are examples of a negative electrode.

[0056] (Electric field of the electric device) Next, the electric fields of the electric devices 1D1 and 1D2 will be described with reference to FIGS. 9 and 10. In FIGS. 9 and 10, only the components necessary for the description are shown, and some components are omitted.

[0057] First, the electric field of the electric device 1D1 will be described. FIG. 9 is a side view showing the electric lines of force in a part of the configuration of the electric device 1D1 of the fourth embodiment. As shown in FIG. 9, the electric device 1D1 receives an electrostatic force due to an electric field E2 generated by the electric power flowing through the high-voltage electrode 11a and the ground electrode 11b. The direction of the electric field E2 is different from the direction of the electric field E1 and is divided into a direction from the high-voltage electrode 11a, which is the positive electrode, to the ground electrode 11b, which is the negative electrode, and a direction from the high-voltage electrode 11a to the embedded electrode 14, which is the negative electrode. The direction of the electric field E2 on the straight line connecting the high-voltage electrode 11a and the ground electrode 11b is obliquely downward with respect to the upper surface 101.

[0058] That is, on the straight line connecting the high-voltage electrode 11a and the ground electrode 11b, the vector component of the electric field E2 in the +X direction is smaller than the vector component of the electric field E1 in the +X direction. For this reason, the electrostatic force received by the conductive foreign matter 13 adhering to the upper surface 101 in the electric field E2 is smaller than the electrostatic force received by the conductive foreign matter 13 adhering to the upper surface 101 in the electric field E1. That is, the movement of the conductive foreign matter 13 in the electric device 1D1 toward the ground electrode 11b along the upper surface 101 is suppressed.

[0059] Next, the electric field of the electric device 1D2 will be described. FIG. 10 is a side view showing the electric lines of force in a part of another configuration of the electric device 1D1 of the fourth embodiment. As shown in FIG. 10, the electric device 1D2 receives an electrostatic force due to an electric field E3 generated by the electric power flowing through the high-voltage electrode 11a and the ground electrode 11b. The direction of the electric field E3 is divided into a direction from the high-voltage electrode 11a, which is the positive electrode, to the ground electrode 11b, which is the negative electrode, and a direction from the high-voltage electrode 11a to the embedded electrode 14, which is the negative electrode, in the same manner as the direction of the electric field E2. The direction of the electric field E3 on the straight line connecting the high-voltage electrode 11a and the ground electrode 11b is obliquely downward with respect to the upper surface 101.

[0060] That is, also in the electric device 1D2 that receives the electrostatic force of the electric field E3, the movement of the conductive foreign matter 13 toward the ground electrode 11b along the upper surface 101 is suppressed.

[0061] In the above-described embodiment, there is a negative electrode (embedded electrode 14 or back electrode 15) disposed between a pair of electrodes (high-voltage electrode 11a and ground electrode 11b) in the X-axis direction and fixed to the lower surface 102 of the insulator 10.

[0062] According to the above-described configuration, the electrical devices 1D1 and 1D2 can suppress the conductive foreign matter 13 from moving toward the ground electrode 11b on the upper surface 101, and thus can suppress a decrease in the insulation performance of the insulator 10 due to the deposition of the conductive foreign matter 13 on the ground electrode 11b.

[0063] (Fifth Embodiment) Next, the electrical device 1E according to the fifth embodiment will be described with reference to FIG. 11. FIG. 11 is a perspective view showing a part of the configuration of the electrical device 1E of the fifth embodiment. As shown in FIG. 11, the electrical device 1E includes a removal unit 16. The removal unit 16 is fixed to the lower surface 102 and adsorbs the conductive foreign matter 13.

[0064] The removal unit 16 is formed in a substantially rectangular parallelepiped shape. The removal unit 16 is fixed to the lower surface 102, for example, by adhesion. The removal unit 16 is disposed near the middle between the high-voltage electrode 11a and the ground electrode 11b in the X-axis direction. The removal unit 16 is disposed below the movement suppression unit 12. The removal unit 16 extends in the Y-axis direction. The length of the removal unit 16 in the Y-axis direction is longer than the length of the insulator 10 in the Y-axis direction. That is, the removal unit 16 protrudes from the insulator 𝟏𝟎 in the Y-axis direction.

[0065] The removal unit 16 is made of, for example, an elastomer having adhesiveness, silica gel having water absorbency, or zeolite. When the removal unit 16 is an elastomer having adhesiveness, the removal unit 16 can adsorb the solid conductive foreign matter 13. When the removal unit 16 is silica gel or zeolite having water absorbency, the removal unit 16 can adsorb the liquid conductive foreign matter 13.

[0066] In the electrical device 1E, the movement suppression unit 12 has the microstructures 124 and 124a. The microstructure 124a is provided on the side surface 103 of the insulator 10. The microstructure 124a is disposed between the microstructure 124 and the removal unit 16 in the Z-axis direction. The microstructure 124a extends in the X-axis direction and the Z-axis direction. The length of the microstructure 124a in the X-axis direction is equal to the length of the microstructure 124 in the X-axis direction. The length of the microstructure 124a in the Z-axis direction is equal to the length (thickness) of the insulator 10 in the Z-axis direction.

[0067] The microstructure 124a has recesses that slightly indent in the +Y direction with respect to the side surface 103 and extend in the Z-axis direction, and a plurality of the recesses are alternately arranged in the X-axis direction. The length of the microstructure 124a in the Y-axis direction (depth with respect to the side surface 103) is sufficiently short with respect to the length of the insulator 10 in the Y-axis direction. The microstructure 124a guides the conductive foreign matter 13 that is induced by the microstructure 124 to move the side surface 103 downward (-Z direction). The microstructure 124a may be provided on a surface of the insulator 10 other than the side surface 103.

[0068] The electrical device 1E receives the electrostatic force by the electric field E1 generated by the electric power flowing through the high-voltage electrode 11a and the ground electrode 11b. Details of the electric field E1 are the same as those of the electrical devices 1, 1A, 1B1, 1B2, 1C, and thus the description thereof is omitted.

[0069] In the electrical device 1E, the conductive foreign matter 13 adhering to a position on the upper surface 101 closer to the high-voltage electrode 11a than the microstructure 124 moves the upper surface 101 in the +X direction by the electrostatic force of the electric field E1. When the conductive foreign matter 13 reaches the microstructure 124, the conductive foreign matter 13 drops into the recess of the microstructure 124 by the action of gravity, is further induced in the Y-axis direction by capillary action, and is discharged from the upper surface 101. Then, the conductive foreign matter 13 discharged from the upper surface 101 drops onto the microstructure 124a provided on the side surface 103 by the action of gravity, is induced by the microstructure 124a, and further moves downward (-Z direction).

[0070] The conductive foreign matter 13 induced to the fine structure portion 124a and moving the side surface 103 downward (-Z direction) contacts and is adsorbed by the removal portion 16 disposed below the fine structure portion 124a. That is, the conductive foreign matter 13 is removed from the insulator 10.

[0071] When the conductive foreign matter 13 is in a liquid state, the conductive foreign matter 13 adsorbed by the removal portion 16 is vaporized by the heat generated by the high-voltage electrode 11a and the ground electrode 11b and released into the space. Thereby, the removal portion 16 that has adsorbed the conductive foreign matter 13 can regenerate the adsorption performance for the conductive foreign matter 13, and thus can maintain the adsorption performance for the conductive foreign matter 13 over a long period of time.

[0072] Also, the electric device 1E may be provided with a heater (not shown) in the vicinity of the removal portion 16. The heater is fixed, for example, by adhesion to the lower surface 102 of the insulator 10. In this case, more of the conductive foreign matter 13 is vaporized by the heat generated by the heater and released into the space. Therefore, the removal portion 16 can maintain the adsorption performance for the conductive foreign matter 13 over a longer period of time.

[0073] In the above embodiment, the electric device 1 is fixed to the lower surface 102 of the insulator 10 and has a removal portion 16 that adsorbs the conductive foreign matter 13.

[0074] According to the above configuration, the electric device 1E can remove the conductive foreign matter 13 discharged from the upper surface 101 from the insulator 10 by the removal portion 16, and thus can suppress a decrease in the insulation performance of the insulator 10 due to the deposition of the conductive foreign matter 13 on the insulator 10.

[0075] (Modification example) Next, a modification example of the fifth embodiment will be described. In the electric device 1E in the modification example, the removal portion 16 is detachably fixed to the lower surface 102 of the insulator 10 by, for example, a double-sided tape.

[0076] When the conductive foreign matter 13 is adsorbed by the removal part 16 and deposited thereon, the area of contact between the conductive foreign matter 13 moving downward (-Z direction) along the side surface 103 and the removal part 16 decreases, and the adsorption performance of the removal part 16 for the conductive foreign matter 13 deteriorates. However, in the modified example, during inspection of the electric device 1E or the like, an operator detaches the removal part 16 on which the conductive foreign matter 13 is deposited and replaces it with another removal part 16. Thereby, it is possible to prevent the adsorption performance of the removal part 16 from deteriorating due to a large amount of the conductive foreign matter 13 being deposited on the removal part 16. Further, during inspection of the electric device 1E or the like, it becomes unnecessary for an operator to remove the insulator 10 and perform a cleaning operation for removing the conductive foreign matter 13 deposited on the removal part 16, and the workability when regenerating the adsorption performance of the removal part 16 for the conductive foreign matter 13 can be improved.

[0077] (Method for manufacturing an electric device) Next, an example of a method for manufacturing an electric device according to each embodiment will be described. First, the high-voltage electrode 11a and the ground electrode 11b are fixed to the upper surface 101 of the insulator 10 while being separated from each other. Then, a movement suppressing part according to each embodiment is provided between the high-voltage electrode 11a and the ground electrode 11b on the upper surface 101 of the insulator 10. For example, in the case of the electric device 1 according to the first embodiment, the movement suppressing part 12 is attached and fixed by adhesion, and in the case of the electric device 1B1 according to the second embodiment, the movement suppressing part 12B1 is attached and fixed by adhesion. Further, for example, in the case of the electric device 1B2 according to the second embodiment, the movement suppressing part 12B2 is provided by machining, and in the case of the electric device 1C according to the third embodiment, the movement suppressing part 12C is provided by machining. Through the above steps, the electric device 1 is manufactured.

[0078] Note that the electric device according to each embodiment can also be manufactured by providing the movement suppressing part according to each embodiment on the upper surface 101 of the insulator 10 and then fixing the high-voltage electrode 11a and the ground electrode 11b while separating them on the upper surface 101.

[0079] In the method for manufacturing the electrical device 1 executed in the above embodiment, the electrical device 1 is manufactured to include an insulator 10 and a pair of electrodes (a high-voltage electrode 11a and a ground electrode 11b) fixed to the upper surface 101 of the insulator 10 and spaced apart from each other in the X-axis direction, and a movement suppression portion 12 is provided on the upper surface 101 of the insulator 10 between the pair of electrodes provided on the upper surface 101 to suppress the movement of the conductive foreign matter 13 on the upper surface 101.

[0080] In the method for manufacturing the electrical device 1 described above, the electrical device 1 is manufactured by performing a process of providing the movement suppression portion 12 on the upper surface 101 of the insulator 10 in the conventional electrical device. Thereby, the electrical device 1 can suppress the conductive foreign matter 13 from moving on the upper surface 101, suppress the conductive foreign matter 13 from depositing on the ground electrode 11b, and thus suppress the deterioration of the insulation performance of the insulator 10.

[0081] As described above, some embodiments of the present invention have been described. However, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0082] 1, 1A, 1B1, 1B2, 1C, 1D1, 1D2, 1E Electrical Device 10, 10D Insulator 11a High-Voltage Electrode 11b Ground Electrode 12, 12A1, 12A2, 12A3, 12A4, 12B1, 12B2, 12C Movement Suppression Portion 13 Conductive Foreign Matter 14 Embedded Electrode 15 Back Electrode 16 Removal Portion 121 Protrusion 122 Recess 124 and 124a microstructural parts E1, E2, and E3 electric fields

Claims

1. An insulator, A pair of electrodes fixed to the upper surface of the insulator and spaced apart from each other in a first direction, A movement suppression portion provided on the upper surface, disposed between the pair of electrodes, and suppressing movement of conductive foreign matter on the upper surface, An electrical device comprising the above.

2. The surface free energy of the movement suppression portion is higher than that of the insulator, The electrical device according to Claim 1.

3. The movement suppression portion suppresses the conductive foreign matter from moving in the first direction, The electrical device according to Claim 1.

4. The movement suppression portion is detachable from the upper surface, The electrical device according to Claim 1.

5. The movement suppression portion has at least one of a convex portion protruding upward and a concave portion recessed downward, The electrical device according to Claim 3.

6. The movement suppression portion guides the conductive foreign matter in a direction intersecting the first direction, The electrical device according to Claim 3.

7. Having a negative electrode disposed between the pair of electrodes in the first direction and fixed to the lower surface of the insulator, The electrical device according to Claim 1.

8. Having a removal portion fixed to the lower surface of the insulator and adsorbing the conductive foreign matter, The electrical device according to Claim 3.

9. The removal portion is detachable from the lower surface, The electrical device according to Claim 8.

10. Manufacturing an electrical device comprising an insulator and a pair of electrodes fixed to the upper surface of the insulator and spaced apart from each other in a first direction, Providing, on the upper surface of the insulator, a movement suppression portion provided on the upper surface, disposed between the pair of electrodes, and suppressing movement of conductive foreign matter on the upper surface, Comprising, A method for manufacturing an electrical device.

Images