JP2005294459A - Arrester device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an arrester device which is grounded to a three-phase bus bar in a small size and at a low cost. <P>SOLUTION: Current-limiting elements 21, 22, 23 of zinc oxide are laminated and unified in a state of a parallel connection via electrode terminals 24, 25 and ground terminal 26, to form a laminated body 11, thereby constituting an arrester circuit obtained by connecting three arresters in parallel. Such a laminated body 11 is formed in correspondence to three phases of a T phase, an S phase and an R phase, and three-phase laminated bodies 11, 12, 13 are laminated through insulating spacers 31, 32 to construct a three-phase arrester unit 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an arrester device installed in each of three-phase buses.

  Arresters are installed between each of the three-phase buses and the ground as lightning protection measures against direct lightning strikes in high-voltage and low-voltage systems. Generally, the arrester wired to each of the three-phase buses of T-phase, S-phase, and R-phase is applied as an individual commercial product, and is used by installing three arresters of the same model on a common base. The Each of the three commercially available arresters is small and inexpensive, but if it is three, it becomes larger and the installation space becomes larger, resulting in higher costs.

Further, a three-phase collective lightning arrester (arrester device) having a structure in which three arresters are housed in one case is known (see, for example, Patent Document 1). This three-phase collective lightning arrester is used for a high-voltage system, and has a structure in which a three-phase internal element, which is a non-linear resistor of zinc oxide, is housed in a cylindrical container and filled with gas. By arranging the arresters (lightning arresters) together, the three-phase arrester device becomes smaller and less expensive.
JP-A-9-213508

  However, the three-phase collective lightning arrester (arrestor device) used in the above-mentioned high-voltage system has a large three-phase internal element itself and is difficult to downsize. It is difficult to reduce the size and cost of a phase arrester device. In addition, because of the structure in which large internal elements are insulated and spaced apart from each other in the container, it is difficult to manufacture with high technology, which increases the manufacturing cost.

  An object of the present invention is to reduce the size of an arrester device in which arresters are wired to each of the three-phase buses, thereby facilitating reduction in manufacturing costs.

  In order to achieve the above-mentioned object, each of the three or more arresters arranged between each of the three-phase buses and the ground includes an electrode terminal between the buses and a ground terminal between the grounds in a current limiting element containing zinc oxide. A structure having a three-phase arrester unit in which the three-phase laminates are stacked and laminated in the respective lamination directions via insulating spacers.

  Here, the three-phase buses are T-phase, S-phase, and R-phase electric wires of a high-voltage system and a low-voltage system, and are each connected to an arrester and grounded at one point. One arrester or a plurality of arresters connected in parallel are installed between each three-phase bus and the ground to constitute the arrester device. The laminated body constituting each of these arresters is configured so that one or a plurality of current limiting elements in the form of a plate or block mainly composed of zinc oxide are sandwiched between an electrode terminal composed of a copper plate or a brass plate and a ground terminal. The number of electrode terminals and ground terminals and the arrangement relationship are appropriately set according to the number of current limiting elements. One three-phase arrester unit is constructed by further laminating and integrating the three-phase laminates in the respective lamination directions. In this case, each three-phase laminate is insulated by an insulating spacer interposed between the laminates, and each three-phase laminate is independent as an arrester. Therefore, since the arresters of the three-phase bus are stacked and integrated, the three-phase arrester device is small and compact, and the pre-fabricated plate-like current limiting elements, terminals, insulating spacers, etc. Since they can be manufactured by appropriately laminating them, facilities for manufacturing are simplified and manufacturing costs can be easily reduced.

  In the present invention, the current limiting element of each of the three-phase laminates has a flat plate shape, and this current limiting device can be laminated with a flat electrode terminal and a ground terminal in the thickness direction. Thus, by laminating the current limiting element and each terminal that are laminated to each other in a flat plate shape, the work of laminating is facilitated, and the laminated body is small and compact with a small thickness. Lamination work is facilitated.

  Furthermore, in the present invention, the current limiting element of each of the three-phase laminates can be divided into a plurality, and the plurality of current limiting elements can be connected in parallel at the electrode terminal and the ground terminal and stacked. In other words, the current capacity of each of the three-phase arresters is set to be large by using a configuration in which each of the three-phase stacks has a plurality of arresters connected in parallel, and a large surge current such as a direct lightning strike is shunted to the parallel-connected arresters. It becomes easy to cope with a large lightning surge.

  Moreover, in this invention, the ground terminal of each three-phase laminated body of a three-phase arrester unit can be connected to a common ground conductor. In this case, a part of the ground terminal is led out from the side surface of each of the three-phase laminates, and each lead-out part is connected to a common ground conductor. As the ground conductor, a metal plate having a large current capacity such as a copper plate similar to the ground terminal can be applied. Stable grounding can be achieved by grounding the ground terminal of each three-phase laminate with a ground conductor.

  Moreover, in this invention, the drawing-out direction with respect to the three-phase arrester unit of the electrode terminal of each three-phase laminated body of a three-phase arrester unit and the ground terminal of each laminated body can be made mutually different. For example, it is possible to derive the electrode terminal of each three-phase laminate above the three-phase arrester unit in the laminating direction and to derive the ground terminal below, so that the wiring on the electrode terminal side and the ground terminal side can be done in this way. Can be separated from each other by a sufficient distance, and a stable insulating structure can be obtained.

  Further, in the present invention, in a state where the three-phase arrester unit is sandwiched by the element pressing members from both ends in the stacking direction, the element pressing members are tightened with the fastening members in the directions approaching each other, and the three-phase stacked bodies are formed. Can be integrated.

  The element pressing member here can be a flat metal plate, a resin insulating plate, etc., and by pressing the three-phase arrester unit from both ends in the stacking direction with a pair of element pressing members, The gaps at the end are eliminated, and the quality of each laminate is stabilized. The fastening member that fastens the three-phase arrester unit from the stacking direction via a pair of element pressing members can be composed of a bolt that penetrates the pair of element pressing members and a nut that is screwed to the bolt. The three-phase arrester unit is integrated by tightening the pair of element pressing members by bolting or nut tightening in a direction approaching each other. As such a bolt, a plurality of bolts arranged in parallel in the axial direction along the outer periphery of the three-phase arrester unit, or a bolt that penetrates the three-phase arrester unit in the stacking direction can be applied.

  Notches into which wirings connected to the electrode terminals of the three-phase laminates are fitted can be formed on the outer periphery of one or both of the pair of element pressing members. This notch of the element pressing member suppresses the outer diameter of the three-phase arrester unit by inserting and inserting the wiring, and positioning the wiring to facilitate the wiring work.

  Moreover, in this invention, the electrode terminal of each three-phase laminated body can be derived | led-out from the several position of a different angle in the circumferential direction of the outer periphery of a three-phase arrester unit. For example, when the three-phase arrester unit has a structure in which three stacked bodies each having a single electrode terminal are stacked, a part of the electrode terminals protrudes from the outer periphery of each three-phase stacked body, and this electrode protruding portion is formed into three. The position is shifted by 90 ° with respect to the outer periphery of the phase arrester unit. By doing in this way, the insulation between the electrode terminal protrusion parts of each three-phase laminate of the three-phase arrester unit can be easily and reliably performed, and high-quality manufacturing and assembly can be performed.

  Further, positioning means for restricting the positions of the three-phase arrester units at different angles in the circumferential direction can be engaged with the electrode terminals of each of the three-phase laminates derived from the outer periphery of the three-phase arrester unit. This positioning means includes an insulating positioning rod inserted into a through hole formed in the protruding portion of the electrode terminal protruding from the outer periphery of each three-phase laminate, a positioning groove in which the outer periphery of the protruding portion of the electrode terminal engages, etc. By positioning the electrode terminal, the electrode terminal does not move relative to the three-phase arrester unit, and the assembly and manufacture of the three-phase arrester unit with stable quality is facilitated.

  Further, in the present invention, the three-phase arrester unit can be housed in an insulating case, the insulating case can be filled with an insulating filler, and the three-phase arrester unit can be insulated and sealed with the filler. Furthermore, the bottom part of the insulating case can be constituted by a grounding element pressing member that is electrically connected to the ground terminal of each three-phase laminate.

  The insulation case here is an insulating cylinder made of reinforced plastic, etc., which houses the three-phase arrester unit and is filled with an insulating filler such as silicone resin or epoxy resin, so that the three-phase arrester unit is protected against moisture. Double insulated and sealed for stable arrester operation over a long period of time. By fixing the element pressing member of the metal plate to the bottom of the insulating cylinder, and connecting this element pressing member to the ground terminal of each three-phase laminate of the three-phase arrester unit, it can be used as a grounding base. One point grounding of the body becomes easy. In this case, lead out the electrode terminals of each three-phase laminate from the upper part of the three-phase arrester unit housed in the insulation case and the insulation base of the grounding base with an external lead wire or terminal plate, and use the external lead wire or terminal The plate can be directly connected to the three-phase bus, or can be connected to the three-phase bus via a terminal block in which an external lead wire or a terminal plate is detachably fitted to the upper part of the insulating case.

  According to the present invention, the three-phase arrester unit is constructed by further stacking and integrating the laminates that are each of the three-phase arresters. Phase arrester devices can be configured in a compact and compact manner, and it is possible to provide an arrester device with excellent practical value that can easily reduce the installation space and cost of an arrester device equipped with a three-phase arrester. . In addition, it is possible to manufacture each of the three-phase laminates by a simple process of laminating each of the current limiting element such as a flat plate shape, electrode terminals, ground terminals, and insulating spacers, and the equipment required for such manufacture. Can be simple and can easily reduce the manufacturing cost of a three-phase arrester device.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  The arrester device of FIGS. 1 and 2 is installed between the three-phase bus and the ground. An equivalent circuit of this arrester device is shown in FIG. 6 and has three arrester circuits Zt, Zs, Zr connected to the three-phase buses of the T-phase bus 1t, the S-phase bus 1s, and the R-phase bus 1r, Each arrester circuit Zt, Zs, Zr is configured by connecting three arresters Za, Zb, Zc in parallel.

  The arrester device of FIG. 1 is characterized by a three-phase arrester unit 10 having a laminated structure in which three arrester circuits Zt, Zs, and Zr are integrated. The three-phase arrester unit 10 includes three laminated bodies 11, 12, and 13 constituting three arrester circuits Zt, Zs, and Zr via two insulating spacers 31 and 32, and a pair of element pressers at both ends in the lamination direction. The laminated bodies 11 to 13 are fastened and integrated in the laminating direction by the members 41 and 42 and the fastening member 50. The three-phase arrester unit 10 is housed in one insulating case 60, insulated and filled with an insulating filler 70 filled in the insulating case 60, and wired to a terminal block 61 that closes the upper end opening of the insulating case 60. Two compact arrestor devices are manufactured.

  A specific example of the three laminated bodies 11 to 13 in the three-phase arrester unit 10 is shown in FIG. 4, and an exploded perspective view is shown in FIG. Hereinafter, the three stacked bodies 11, 12, and 13 are referred to as a first stacked body 11, a second stacked body 12, and a third stacked body 13 as necessary.

  The first laminated body 11 has a structure in which three current limiting elements 21, 22, 23 having the same size, which are non-linear resistance elements containing zinc oxide, are laminated through electrode terminals 24, 25 and a ground terminal 26 and integrated. It is. Each of the three current limiting elements 21 to 23 is a circular flat plate, and is laminated in the thickness direction in a concentric state. The electrode terminals 24 and 25 are two types of metal flat plates such as a copper plate and a brass plate, and one electrode terminal 24 is an element wiring terminal for connecting the two current limiting elements 21 and 22, and a specific example is shown in FIG. The other electrode terminal 25 is an electrode lead-out terminal, and a specific example is shown in FIG. The element wiring electrode terminal 24 shown in FIG. 7 has a pair of disk-like contact portions 24a and 24b of the same size facing each other in parallel and protruding in a U-shaped cross section connecting the outer peripheral parts of both the contact portions 24a and 24b. It has a portion 24c, and positioning means, for example, a positioning hole 24d penetrating in the vertical direction is formed in the protruding portion 24c. The diameters of the contact portions 24a and 24b are set to be about several mm smaller than the diameter of the current limiting elements 21 to 23. The electrode lead-out electrode terminal 25 in FIG. 8 has a disk-like contact portion 25a and a flat plate-like protruding portion 25c extending from a part of the outer periphery of the contact portion 25a, and a positioning hole 25d is formed in the protruding portion 25c. An electrode lead attachment hole 25f is formed. The diameter of the contact portion 25a is also set to be about several mm smaller than the diameter of the current limiting elements 21-23.

  Further, the ground terminal 26 has the same shape as the element wiring electrode terminal 24, and as shown in FIG. 9, a pair of disk-shaped contact portions 26a and 26b of the same size facing each other and both the contact portions 26a. , 26b and a protruding portion 26c having a U-shaped cross-section for connecting a part of the outer periphery thereof, and a positioning hole 26d penetrating vertically in the protruding portion 26c. The diameters of the contact portions 26a and 26b are also set to be a few millimeters smaller than the diameter of the current limiting elements 21 to 23.

  The first stacked body 11 is configured by stacking as follows. For example, a contact portion 24 b of the element wiring electrode terminal 24 and a contact portion 25 a of the electrode lead-out electrode terminal 25 are interposed between the two current limiting elements 22 and 23 so as to be placed on the lower surface of the lower current limiting element 23. One contact portion 26 b of the ground terminal 26 is overlapped, and the other contact portion 26 a is overlapped on the upper surface of the upper current limiting element 22. The remaining current limiting element 21 is overlapped on the contact part 26a on the current limiting element 22, and the other contact part 24a of the electrode terminal 24 is overlapped on the current limiting element 21 which is the uppermost layer. The first laminated body 11 laminated in this way is pressed in the laminating direction to electrically and mechanically connect the current limiting elements 21 to 23 and the terminals 24 to 26, thereby connecting the parallel-connected 3 shown in FIG. 6. Two arresters Za to Zc are formed. The circular current limiting elements 21 to 23 and the circular contact portions 24a to 26a of the respective terminals are concentrically stacked so that the end surface of the large diameter element extends from the end surface of the small diameter contact portion to about 1 to 2 mm as shown in FIG. By separating at a distance g, it is possible to prevent flashing from the creeping surface of the element and to cope with a large lightning surge.

  The 2nd laminated body 12 and the 3rd laminated body 13 are the structures similar to the 1st laminated body 1, The same code | symbol is attached | subjected to the same part and description is abbreviate | omitted. As shown in FIGS. 4 and 5, the electrode lead-out electrode terminals 25 of the second stacked body 12 and the third stacked body 13 are arranged on the uppermost current limiting element 21. Moreover, each protrusion part 25c-25c of each electrode lead electrode terminal 25-25 of the 1st-3rd laminated bodies 11-13 is the protrusion position in the circumferential direction of the three-phase arrester unit 10 so that it may mention later in FIG. Are made different at intervals of 90 ° in the circumferential direction.

  The first stacked body 11 and the second stacked body 12 are stacked via an insulating spacer 31, and the second stacked body 12 and the third stacked body 13 are stacked via another insulating spacer 32. The insulating spacers 31 and 32 are discs having the same size as the current limiting elements 21 to 23 and are formed of a hard insulating material such as polycarbonate. In a state where the three laminated bodies 11 to 13 are laminated, the common ground conductor 27 is screwed or the like to the projecting portion 26c of the ground terminal 26 projecting from a part of the peripheral surface of each of the laminated bodies 11 to 13. Be joined. The ground conductor 27 is a vertically long metal plate, and grounds the arresters Za to Zc of FIG. 6 formed by the three laminated bodies 11 to 13 at one point.

  The three stacked bodies 11 to 13 may be stacked using the pair of upper and lower element pressing members 41 and 42 and the fastening member 50 as follows. As shown in FIG. 3, when the third stacked body 13, the second stacked body 12, and the first stacked body 11 are stacked on the lower element pressing member 41 in this order, the lower element pressing member 41 is a disc. The upper element pressing member 42 is a disk-shaped hard insulating plate such as polycarbonate. Further, as shown in FIG. 1, screw holes 51 are formed at four positions at 90 ° intervals around the upper surface of the lower element pressing member 41. In each of the four screw holes 51, for example, an insulating fastening bolt 52, which is a fastening member 50, is screwed. Bolt insertion holes (not shown) are formed at four locations at 90 ° intervals on the periphery of the upper element pressing member 42, and at three positions at 90 ° intervals on the outer periphery of the element pressing member 42 as shown in FIG. An electrode lead-out line insertion notch 54 is formed.

  The third stacked body 13 is placed on the center of the lower element pressing member 41 as the lowermost layer, and the insulating spacer 32, the second stacked body 12, the insulating spacer 31, and the first stacked body 11 are sequentially stacked thereon. A three-phase arrester unit 10 is constructed. Alternatively, the three-phase arrester unit 10 in which the insulating spacer 32, the second stacked body 12, the insulating spacer 31, and the first stacked body 11 are stacked on the third stacked body 13 is placed on the element pressing member 41. The element pressing member 42 is placed on the first laminate 11 constituting the uppermost layer of the three-phase arrester unit 10, and the fastening bolts 52 are inserted one by one into the bolt insertion holes at the four peripheral portions of the element pressing member 42. Then, it is screwed into the screw hole 51 of the lower element pressing member 41. One of the four fastening bolts 52 shown in FIG. 10 is inserted into the positioning holes 24d and 25d formed in the projecting portions 24c and 25c of the electrode terminals 24 and 25 of the first laminate 11, and this 1 The second tightening bolt 52 separated from the main body by a circumferential angle of 90 ° is inserted into the positioning holes 24d and 25d of the electrode terminals 24 and 25 of the second laminate 12, and further separated at a circumferential angle of 90 °. The third tightening bolt 52 is inserted into the positioning holes 24 d and 25 d of the electrode terminals 24 and 25 of the third stacked body 13. A projecting portion 26c of the grounding terminal 26 projecting the fourth tightening bolt 52 further away from the third tightening bolt 52 by a circumferential angle of 90 ° from the outer periphery of the first to third laminated bodies 11 to 13. Is inserted into the positioning hole 26d. By inserting the four fastening bolts 52 arranged at intervals of 90 ° in this way into the positioning holes 24d to 26d of the protruding portions 24C to 26c of the terminals protruding at the outer periphery of the three-phase arrester unit 10 at intervals of 90 °. , The positional deviation due to the rotation of the electrode terminals 25 and the grounding terminal 26 of each of the laminated bodies 11 to 13 is prevented, and the position of the protruding portion of each terminal is regulated at a fixed position 90 degrees apart, so that the stable between the terminals Creepage distance can be secured and insulation between terminals is stabilized.

  By tightening the four tightening bolts 52 toward the element pressing member 41, the three-phase arrester unit 10 is clamped by the element pressing members 41 and 42 from above and below and fastened in the element stacking direction. ˜13 are integrated in a compact manner. At the same time, the lower element pressing member 41 and the ground terminal 26 of the third stacked body 13 are electrically connected, and the ground terminals 26 of the stacked bodies 11 to 13 are grounded at one point via the ground conductor 27. Before and after this, the three electrode lead wires 80 corresponding to the electrode terminal protruding portions 25c of the three stacked bodies 11 to 13 protruding from the outer periphery of the three-phase arrester unit 10 at intervals of 90 ° are connected. A wiring, for example, the tip end portion of the electrode lead wire 80 is connected to the protruding portion 25c by the connecting screw 81 using the terminal mounting hole 25f formed in the protruding portion 25c of the electrode terminal 25 of each stacked body 11-13. The three lead wires 80 are insulated wires, and are both drawn out to the upper side opposite to the grounding base side of the three-phase arrester unit 10, and are inserted into the notches 54 formed at the three outer peripheral positions of the upper element pressing member 42. Pulled upward. By fitting the lead wire 80 into the notch 54, the lead wire 80 does not protrude to the outer periphery of the pressing member 42, and the outer diameter of the three-phase arrester unit 10 including the pressing member 42 can be suppressed. Further, the notch 54 positions the lead wire 80 to facilitate the work of inserting the three-phase arrester unit 10 into the insulating case 60 and the wiring work to the terminal block 61.

  The insulating case 60 is an FRP cylinder having an upper and lower opening, and has pin insertion holes 62 at upper and lower ends as shown in FIG. The lower end portion of the insulating case 60 is inserted into the outer periphery of the element pressing member 41 to which the three-phase arrester unit 10 is assembled, and the pin 64 is inserted from the pin insertion hole 62 into the pin hole 63 formed in the outer periphery of the element pressing member 41. Secure with adhesive. Thereafter, an insulating filler 70 of silicon resin is filled in the insulating case 60 in such an amount that the upper end of the three-phase arrester unit 10 is hidden. Since the three-phase arrester unit 10 is in a state of being fastened with sufficient strength in the stacking direction, there is no gap between layers such as a current limiting element and an electrode terminal, and there is no possibility of the filler 70 penetrating between the layers. The quality of the three-phase arrester unit 10 that is insulated and sealed is stabilized. Further, if necessary, an O-ring 71 for sealing is fitted on the outer periphery of the element pressing member 41, and the inner periphery of the lower end of the insulating case 60 is brought into elastic contact with the O-ring 71, so that the insulating case 60 and the element pressing member 41 are The leakage of the filler 70 from the gap is prevented, and the filler 70 is prevented from penetrating into the gap between the pin hole 63 and the pin 64 and leaking outside. Further, the O-ring 71 ensures a sealing property between the element pressing member 41 and the insulating case 60. The filler 70 and the O-ring 71 are sealed so that moisture entering from the insulating case 60 does not reach the three-phase arrester unit 10 to improve the durability of the arrester device. In addition, since the filler 70 is excellent in such sealing performance, it is possible to omit the O-ring 71 using only the filler 70.

  When the three-phase arrester unit 10 is stored in the insulating case 60, the terminal block 61 is attached to the upper end portion of the insulating case 60, and the three lead wires 80 of the three-phase arrester unit 10 are wired to the terminal block 61. The insulating case 60 and the terminal block 61 may be attached by inserting the pins 64 and bonding them with an adhesive, like the element pressing member 41. The terminal block 61 has a disk-shaped base 61a fitted to the insulating case 60 and a terminal mounting part 61b protruding from the upper surface of the base 61a. The terminal mounting part 61b has T-phase, S-phase, and R-phase. Three terminal plates 62 are provided. A transparent cover 63 is detachably attached to the terminal mounting portion 61b to prevent the charging portion such as the terminal plate 62 from being exposed to the outside.

  Next, another embodiment of the present invention will be described with reference to FIGS. FIG. 11 shows an outline of the three-phase arrester unit 10, in which stacked bodies 11 to 13 of T phase, S phase, and R phase are stacked and stacked via insulating spacers 31 and 32. Each laminated body 11-13 is comprised by laminating | stacking donut-shaped current limiting elements 21-23 as shown in FIG. 12 via the electrode terminal and grounding terminal which are not shown in figure. The tightening bolt 52 is passed through the center of the three-phase arrester unit 10 such that one tightening bolt 52 is inserted into the through hole 15 formed at the center of the donut-shaped current limiting elements 21 to 23. The element pressing members 41 and 42 arranged at the upper and lower end portions of the three-phase arrester unit 10 are tightened with the tightening bolts 52 and the nuts 16, and the three-phase arrester unit 10 is fastened from the stacking direction of the elements.

  As shown in FIG. 11, by fastening the three-phase arrester unit 10 with a single fastening bolt 52 penetrating the center portion, the fastening member provided on the outer periphery of the three-phase arrester unit 10 can be omitted. The outer diameter of the phase arrester unit 10 can be reduced. Further, a plurality of tightening bolts penetrating the three-phase arrester unit 10 may be used as positioning means for restricting the rotation of the laminated current limiting elements and electrode terminals.

  In the above-described embodiment, the arrester device in which the current limiting elements 21 to 23, the electrode terminals 24 and 25, and the ground terminal 26 have a disk shape has been described, but the shape of these elements and terminals is substantially a square plate shape. It is good. If a square plate is used, the size can be further reduced.

  The arrester device of the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the present invention.

It is a side view including the partial cross section of the arrester apparatus which shows embodiment of this invention. It is a top view of the arrester apparatus of FIG. It is a side view at the time of the assembly of the arrester apparatus of FIG. It is a disassembled side view which shows the outline | summary of the three-phase arrester unit in an arrester apparatus. FIG. 5 is an exploded perspective view and a wiring diagram of the three-phase arrester unit of FIG. 4. FIG. 5 is an equivalent circuit diagram of the three-phase arrester unit of FIG. 4. It is a perspective view at the time of the assembly | attachment of the electrode terminal and current limiting element in a three-phase arrester unit. It is a perspective view at the time of the assembly | attachment of another electrode terminal and a current limiting element. It is a perspective view at the time of the assembly | attachment of the ground terminal and current limiting element in a three-phase arrester unit. It is a top view of a three-phase arrester unit. It is sectional drawing of the principal part of the three-phase arrester unit which shows other embodiment. It is a perspective view of the current limiting element in the three-phase arrester unit of FIG.

Explanation of symbols

1 Three-phase bus 10 Three-phase arrester unit 11 Laminated body (T phase)
12 Laminate (S phase)
13 Laminate (R phase)
21, 22, 23 Current limiting element 24, 25 Electrode terminal 24 c, 25 c Projecting portion 26 Ground terminal 24 d, 25 d, 26 d Positioning means, positioning hole 27 Ground conductor 31, 32 Insulating spacer 41, 42 Element pressing member 50 Fastening member 52 Fastening Attached bolt 54 Notch 70 Filler Za to Zc Arrester Zt to Zr Arrester circuit 80 Wiring, lead wire

Claims (11)

  Each of the arresters disposed between the three-phase buses and the ground is a laminate in which electrode terminals to be connected between the bus bars and a ground terminal are stacked on a current limiting element including zinc oxide. An arrester device comprising a three-phase arrester unit in which each laminate is stacked and laminated in the respective stacking directions via insulating spacers.   The laminate includes a flat current limiting element, a flat electrode terminal disposed on one surface side of the current limiting element, and a flat ground terminal disposed on the other surface side of the current limiting element. The arrester device according to claim 1, wherein the arrester device is configured by stacking layers.   3. The arrester device according to claim 1, wherein the current limiting element of the laminate is divided into a plurality of parts, and each of the plurality of current limiting elements is connected in parallel at an electrode terminal and a ground terminal.   2. The arrester device according to claim 1, wherein the ground terminals of the three-phase laminates of the three-phase arrester unit are connected to a common ground conductor.   2. The arrester device according to claim 1, wherein the lead-out directions of the electrode terminals of the three-phase laminates of the three-phase arrester unit and the ground terminals of the laminates with respect to the three-phase arrester unit are different from each other.   In a state where the three-phase arrester unit is sandwiched between the element pressing members from both ends in the stacking direction, the element pressing members are tightened with the fastening members in the directions approaching each other, and the three-phase stacked bodies are integrated. The arrester device according to claim 1.   The arrester device according to claim 6, wherein a notch into which a wiring connected to an electrode terminal of each of the three-phase laminates is fitted is formed on an outer periphery of the element pressing member.   2. The arrester device according to claim 1, wherein electrode terminals of each three-phase laminate are derived from a plurality of positions at different angles in the circumferential direction of the outer periphery of the three-phase arrester unit.   The electrode terminal of each three-phase laminate derived from the outer periphery of the three-phase arrester unit is engaged with positioning means for restricting the respective positions at different angles in the circumferential direction of the three-phase arrester unit. The arrester device according to claim 7.   The arrester device according to claim 1, wherein the three-phase arrester unit is housed in an insulating case, and the insulating case is filled with an insulating filler.   The arrester device according to claim 10, wherein a bottom portion of the insulating case is configured by a grounding element pressing member that conducts with a ground terminal of each of the three-phase laminates.