Stationary induction coil

Abstract

To provide a stationary induction device capable of suppressing dielectric breakdown.SOLUTION: A stationary induction device of the embodiment has an iron core and a winding portion. The winding portion includes unit coils arranged in an axial direction of the iron core. The unit coil has a pair of sections aligned in the axial direction of the iron core. A first section and a second section are formed by winding a pair of conductors adjacent to each other in a radial direction of the iron core. The pair of conductors in the first section are a first conductor disposed on the first side in the radial direction and a second conductor disposed on the second side in the radial direction at an end portion on the first side in the radial direction. The number of turns of the second conductor in the first section is less than the number of turns of the first conductor by one.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] FIELD OF THE INVENTION An embodiment of the present invention relates to a static induction appliance. [Background technology]

[0002] Static induction devices such as transformers and reactors are used, and it is necessary to suppress insulation breakdown in these devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 62-229915 [Patent Document 2] Japanese Patent Application Publication No. 168220 / 1983 [Patent Document 3] Patent No. 3505557 Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION An object of the present invention is to provide a static induction device capable of suppressing dielectric breakdown. [Means for solving the problem]

[0005] The stationary induction electric machine of the embodiment has an iron core and a winding section. The winding section is arranged coaxially with the iron core. The winding section has unit coils arranged in the axial direction of the iron core. The unit coils have a pair of sections arranged in the axial direction of the iron core. The pair of sections is a first section arranged on a first axial side and a second section arranged on a second axial side opposite the first axial side. The first and second sections are formed by winding a pair of conductors adjacent to each other in the radial direction around the iron core. The pair of conductors in the first section are a first conductor arranged on the first radial side at an end of the first radial side and a second conductor arranged on a second radial side opposite the first radial side. The pair of conductors in the second section are a third conductor arranged on the first radial side at an end of the first radial side and a fourth conductor arranged on the second radial side. The number of turns of the second conductor in the first section is one turn less than the number of turns of the first conductor. An end portion on the second radial side of the first conductor in the first section is connected to an end portion on the second radial side of the third conductor in the second section. An end portion on the first radial side of the third conductor in the second section is connected to an end portion on the first radial side of the second conductor in the first section. An end portion on the second radial side of the second conductor in the first section is connected to an end portion on the second radial side of the fourth conductor in the second section. The unit coil arranged on the first axial side is referred to as the first unit coil, and the unit coil arranged on the second axial side of the first unit coil is referred to as the second unit coil. An end portion on the first radial side of the fourth conductor in the second section of the first unit coil is connected to an end portion on the first radial side of the first conductor in the first section of the second unit coil. [Brief explanation of the drawings]

[0006] [Figure 1] Conceptual diagram of a static induction electric device. [Figure 2] FIG. 2 is a schematic configuration diagram of a winding section according to the embodiment. [Figure 3] FIG. 10 is a schematic configuration diagram of a winding section in a modified example of the embodiment. [Figure 4] FIG. 10 is a schematic configuration diagram of a winding section in a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, a static induction device according to an embodiment will be described with reference to the drawings. 1 is a conceptual diagram of a static induction device 1. The static induction device 1 has an iron core 2 and a winding portion 4. The iron core 2 is formed in a cylindrical shape.

[0008] In this application, the Z direction, R direction, and θ direction of the cylindrical coordinate system are defined as follows: The Z direction is the axial direction of the central axis of the iron core 2. For example, the Z direction is the vertical direction, and the +Z side is the upward direction. The -Z side is the downward direction. The R direction is the radial direction of the iron core 2. The +R side is the radially outward side, a direction away from the central axis of the iron core 2. The -R side is the radially inward side, a direction approaching the central axis of the iron core 2. The θ direction is the circumferential direction of the iron core 2. The +θ side is the rotation direction of a right-handed screw progressing in the +Z direction. For example, the R direction and the θ direction are horizontal directions.

[0009] The iron core 2 is made of a magnetic material and is disposed on the −R side of the winding portion 4. A tank (not shown) is arranged on the +R side of the winding section 4. The tank houses the iron core 2 and the winding section 4. The iron core 2 and the tank are grounded. An insulating fluid (insulating oil or insulating gas) is sealed inside the tank. The iron core 2 and the winding section 4 are arranged at a distance from each other, and a flow path for the insulating fluid is formed between them. The winding section 4 and the tank are arranged at a distance from each other, and a flow path for the insulating fluid is formed between them. The winding section 4 is cooled by the insulating fluid flowing through the flow path.

[0010] The winding section 4 is formed in a cylindrical shape and is arranged coaxially with the iron core 2. The winding section 4 is formed by winding a conductor W in the θ direction. The conductor W is a flat wire, a composite flat wire made by bundling flat wires, or the like. The conductor W is wound with its outer periphery covered with an insulating material such as kraft paper or PET film.

[0011] The winding section 4 is a high-cell cap disc winding (interleaved winding). The winding section 4 has a plurality of unit coils C arranged in the Z direction. Each unit coil C has a pair of sections S arranged in the Z direction. A spacer (not shown) is arranged between adjacent sections S in the Z direction. The spacers are spaced apart in the θ direction, and a flow path for insulating fluid is formed between adjacent spacers.

[0012] Fig. 2 is a schematic diagram of the winding section 4 in the embodiment. Fig. 2 to Fig. 4 are enlarged views of a portion corresponding to portion P in Fig. 1. In Fig. 2 to Fig. 4, the winding order of the conductor W in the winding section 4 is shown in a cross section of the conductor W.

[0013] The winding portion 4 has unit coils C1 and C2 aligned in the Z direction. The unit coils C1 and C2 are a first unit coil C1 on the +Z side and a second unit coil C2 on the -Z side. The first unit coil C1 has a pair of sections S1 and S2 aligned in the Z direction. The pair of sections S1 and S2 are a first section S1 on the +Z side and a second section S2 on the -Z side.

[0014] The first section S1 has a pair of conductors W1, W2 wound adjacent to each other in the R direction. The pair of conductors W1, W2 is a first conductor W1 and a second conductor W2. At the end of the first section S1 in the +R direction, the first conductor W1 is arranged on the +R side, and the second conductor W2 is arranged on the -R side.

[0015] The second section S2 has a pair of conductors W3 and W4 wound adjacent to each other in the R direction. The pair of conductors W3 and W4 is the third conductor W3 and the fourth conductor W4. At the end of the second section S2 in the +R direction, the third conductor W3 is arranged on the +R side, and the fourth conductor W4 is arranged on the -R side.

[0016] The first conductor W1 forms turns 1-5 from the +R side to the -R side. The third conductor W3 forms turns 6-10 from the -R side to the +R side. The second conductor W2 forms turns 11-14 from the +R side to the -R side. The fourth conductor W4 forms turns 15-19 from the -R side to the +R side. These are connected in order to form the first unit coil C1.

[0017] The second unit coil C2 is formed in the same manner as the first unit coil C1 and is connected to the first unit coil C1. The high-cell-cap disc winding has a large series capacitance, and therefore has excellent resistance to shock voltages caused by lightning and other sources.

[0018] In the first section S1 of the winding portion 4 of the embodiment, the number of turns of the second conductor W2 is one turn less than the number of turns of the first conductor W1. In the example of Fig. 2, the number of turns of the first conductor W1 is five, while the number of turns of the second conductor W2 is four. In the second section S2, the third conductor W3 and the fourth conductor W4 each have the same number of turns, five. The number of turns of each conductor W is not limited to the example of Fig. 2.

[0019] The first section S1 has a spacer SP between a pair of adjacent conductors W1 and W2. The spacer SP is made of electrically insulating pressboard or the like. Pressboard is made by compressing and molding paper. The spacer SP has a size equivalent to one turn of the second conductor W2. This makes the outer shape of the first section S1 the same as the outer shape of the second section S2. In the example of FIG. 2, the spacer SP is disposed between the third turn of the first conductor W1 and the thirteenth turn of the second conductor W2. The position of the spacer SP is not limited to the example of FIG. 2.

[0020] The following describes a manufacturing method (winding method) for the winding section 4. The winding section 4 is manufactured by continuously winding a pair of long conductors. A pair of conductors are wound in the first section S1 as the first conductor W1 and the second conductor W2. The first conductor W1 and the second conductor W2 are wound adjacent to each other in the R direction from the +R side to the -R side. During winding in the first section S1, a spacer SP is inserted between the pair of conductors W1 and W2. After completing four windings, the second conductor W2 is bent toward the -Z side. The second conductor W2 is wound in the second section S2 as the third conductor W3. After completing five windings, the first conductor W1 is bent toward the -Z side. The first conductor W1 is wound in the second section S2 as the fourth conductor W4.

[0021] The pair of conductors is wound as the fourth conductor W4 and the third conductor W3 in the second section S2. The fourth conductor W4 and the third conductor W3 are wound adjacent to each other in the R direction, from the -R side to the +R side. For example, when the first conductor W1 and the second conductor W2 are wound in the +θ direction from the +R side to the -R side, the fourth conductor W4 and the third conductor W3 are wound in the same +θ direction from the -R side to the +R side. After five windings, the fourth conductor W4 and the third conductor W3 are bent to the -Z side. The fourth conductor W4 and the third conductor W3 of the first unit coil C1 are wound as the second conductor W2 and the first conductor W1 in the first section S1 of the second unit coil C2.

[0022] A pair of crossover wires is generated at the -R side end between the first section S1 and the second section S2 of the first unit coil C1. The pair of crossover wires is a crossover wire between the first conductor W1 and the fourth conductor W4 and a crossover wire between the second conductor W2 and the third conductor W3. This pair of crossover wires is cut. Then, as shown in FIG. 2, the -R side end of the first conductor W1 in the first section S1 is connected to the -R side end of the third conductor W3 in the second section S2. Also, the -R side end of the second conductor W2 in the first section S1 is connected to the -R side end of the fourth conductor W4 in the second section S2. These connections are made by, for example, reconnecting the cut crossover wires.

[0023] A pair of crossover wires is generated at the +R side end between the second section S2 of the first unit coil C1 and the first section S1 of the second unit coil C2. The pair of crossover wires is a crossover wire between the fourth conductor W4 of the first unit coil C1 and the second conductor W2 of the second unit coil C2, and a crossover wire between the third conductor W3 of the first unit coil C1 and the first conductor W1 of the second unit coil C2. This pair of crossover wires is cut. Then, as shown in FIG. 2 , the +R side end of the fourth conductor W4 in the second section S2 of the first unit coil C1 is connected to the +R side end of the first conductor W1 in the first section S1 of the second unit coil C2. This sequentially connects the first unit coil C1 and the second unit coil C2.

[0024] 2, the +R side end of the third conductor W3 in the second section S2 of the first unit coil C1 is connected to the +R side end of the second conductor W2 in the first section S1 of the first unit coil C1. As a result, in the first unit coil C1, the first conductor W1, the third conductor W3, the second conductor W2, and the fourth conductor W4 are connected in this order. By repeating the above steps for a plurality of unit coils C, the winding section 4 is completed.

[0025] FIG. 4 is a schematic diagram of the winding section 4 in the comparative example. In the comparative example, the number of turns of the pair of conductors in each section is the same. In the comparative example, the 6th turn of the winding section 4 is arranged at the -R side end of the second section S2 of the first unit coil C1. The 35th turn of the winding section 4 is arranged at the -R side end of the first section S1 of the second unit coil C2. A potential difference equivalent to 29 turns occurs between the two. This potential difference is the maximum potential difference that occurs between adjacent sections at the -R side end of the winding section 4 in the comparative example. This potential difference is added to the potential difference between the winding section 4 and the -R side iron core 2 (see FIG. 1), and there is a possibility that insulation breakdown will occur between the winding section 4 and the iron core 2.

[0026] In the comparative example, the first turn of the winding unit 4 is disposed at the +R side end of the first section S1 of the first unit coil C1. The 20th turn of the winding unit 4 is disposed at the +R side end of the second section S2 of the first unit coil C1. A potential difference equivalent to 19 turns occurs between the two. This potential difference is the maximum potential difference that occurs between adjacent sections at the +R side end of the winding unit 4 of the comparative example. This potential difference is added to the potential difference between the winding unit 4 and the +R side tank, which may cause dielectric breakdown between the winding unit 4 and the tank.

[0027] Various high-cell cap disc windings have been proposed to reduce the potential difference that occurs between adjacent sections at the R-direction ends of the winding section 4. However, these conventional proposals only reduce the potential difference that occurs at either the +R or -R end of the winding section 4.

[0028] In the embodiment shown in FIG. 2, the fifth turn of the winding section 4 is disposed at the -R side end of the first section S1 of the first unit coil C1. The fifteenth turn of the winding section 4 is disposed at the -R side end of the second section S2 of the first unit coil C1. A potential difference equivalent to 10 turns is generated between the two. This potential difference is the maximum potential difference generated between adjacent sections at the -R side end of the winding section 4 of the embodiment. This potential difference is approximately one-third of the potential difference generated at the -R side end of the comparative example. This suppresses dielectric breakdown between the winding section 4 and the iron core 2.

[0029] In the embodiment shown in FIG. 2, the 10th turn of the winding unit 4 is disposed at the +R side end of the second section S2 of the first unit coil C1. The 20th turn of the winding unit 4 is disposed at the +R side end of the first section S1 of the second unit coil C2. A potential difference equivalent to 10 turns is generated between the two. This potential difference is the maximum potential difference generated between adjacent sections at the +R side end of the winding unit 4 of the embodiment. This potential difference is approximately half the potential difference generated at the +R side end of the comparative example. This suppresses dielectric breakdown between the winding unit 4 and the tank.

[0030] As described above in detail, the stationary induction electric device 1 of the embodiment has an iron core 2 and a winding section 4. The winding section 4 is arranged coaxially with the iron core 2. The winding section 4 has unit coils C1 and C2 aligned in the Z direction. The unit coils C1 and C2 each have a pair of sections S1 and S2 aligned in the Z direction. The pair of sections S1 and S2 is a first section S1 arranged on a first side (+Z side) in the Z direction, and a second section S2 arranged on a second side (-Z side) in the Z direction opposite the first side (+Z side) in the Z direction. The first section S1 and the second section S2 are formed by winding a pair of conductors adjacent to each other in the R direction. The pair of conductors in the first section S1 is a first conductor W1 arranged on the first side (+R side) in the R direction at the end of the first side (+R side) in the R direction, and a second conductor W2 arranged on the second side (-R side) in the R direction, which is opposite the first side (+R side) in the R direction. The pair of conductors in the second section S2 is a third conductor W3 arranged on the first side (+R side) in the R direction at the end of the first side (+R side) in the R direction, and a fourth conductor W4 arranged on the second side (-R side) in the R direction at the end of the first side (+R side) in the R direction. The number of turns of the second conductor W2 in the first section S1 is one turn less than the number of turns of the first conductor W1. The end of the first conductor W1 in the first section S1 on the second side (-R side) in the R direction is connected to the end of the third conductor W3 in the second section S2 on the second side (-R side) in the R direction. An end of the third conductor W3 in the second section S2 on a first side (+R side) in the R direction is connected to an end of the second conductor W2 in the first section S1 on a first side (+R side) in the R direction. An end of the second conductor W2 in the first section S1 on a second side (-R side) in the R direction is connected to an end of the fourth conductor W4 in the second section S2 on a second side (-R side) in the R direction. The unit coil arranged on the first side (+Z side) in the Z direction is referred to as the first unit coil C1, and the unit coil arranged on the second side (-Z side) in the Z direction of the first unit coil C1 is referred to as the second unit coil C2. An end of the first unit coil C1 on a first side (+R side) in the R direction of the fourth conductor W4 in the second section S2 is connected to an end of the second unit coil C2 on the first side (+R side) in the R direction of the first conductor W1 in the first section S1.

[0031] This reduces the potential difference generated between adjacent sections at both ends on the +R and −R sides of winding 4. This prevents dielectric breakdown at both ends of winding 4 in the R direction.

[0032] The first section S1 has a spacer SP between a pair of adjacent conductors W1, W2, which corresponds to one turn of the second conductor W2. The spacer SP is made of an electrically insulating material. This makes the outer shape of the first section S1 equal to the outer shape of the second section S2.

[0033] In the winding portion 4 of the embodiment shown in Figure 2, the +R side corresponds to the first side in the R direction, and the -R side corresponds to the second side in the R direction. However, the winding portion 4 of the embodiment may be reversed in the R direction. In this case, the -R side corresponds to the first side in the R direction, and the +R side corresponds to the second side in the R direction. In this case, too, dielectric breakdown at both ends of the winding portion 4 in the R direction is suppressed.

[0034] In the winding portion 4 of the embodiment shown in FIG. 2, the +Z side corresponds to the first side in the Z direction, and the −Z side corresponds to the second side in the Z direction. 3 is a schematic diagram of a winding section 4 in a modified example of the embodiment. The winding section 4 in the modified example is the winding section 4 in the embodiment reversed in the Z direction. In this case, the -Z side corresponds to the first side in the Z direction, and the +Z side corresponds to the second side in the Z direction. In the modified example, the winding order of the conductor shown in the cross section of the conductor is reversed compared to the embodiment.

[0035] The modified stationary induction electric device 1 has an iron core 2 and a winding section 4. The winding section 4 is arranged coaxially with the iron core 2. The winding section 4 has unit coils C1 and C2 aligned in the Z direction. The unit coils C1 and C2 have a pair of sections S1 and S2 aligned in the Z direction. The pair of sections S1 and S2 is a first section S1 arranged on a first side (-Z side) in the Z direction and a second section S2 arranged on a second side (+Z side) in the Z direction opposite the first side (-Z side) in the Z direction. The first section S1 and the second section S2 are formed by winding a pair of conductors adjacent to each other in the R direction. The pair of conductors in the first section S1 is a first conductor W1 arranged on the first side (+R side) in the R direction at the end of the first side (+R side) in the R direction and a second conductor W2 arranged on the second side (-R side) in the R direction opposite the first side (+R side) in the R direction. The pair of conductors in the second section S2 are a third conductor W3 arranged on the first side (+R side) in the R direction and a fourth conductor W4 arranged on the second side (-R side) in the R direction at their ends on the first side (+R side) in the R direction. The number of turns of the second conductor W2 in the first section S1 is one turn less than the number of turns of the first conductor W1. The end of the second side (-R side) in the R direction of the first conductor W1 in the first section S1 is connected to the end of the second side (-R side) in the R direction of the third conductor W3 in the second section S2. The end of the first side (+R side) in the R direction of the third conductor W3 in the second section S2 is connected to the end of the first side (+R side) in the R direction of the second conductor W2 in the first section S1. An end of the second conductor W2 in the first section S1 on the second side (-R side) in the R direction is connected to an end of the fourth conductor W4 in the second section S2 on the second side (-R side) in the R direction. The unit coil arranged on the first side (-Z side) in the Z direction is referred to as the first unit coil C1, and the unit coil arranged on the second side (+Z side) in the Z direction of the first unit coil C1 is referred to as the second unit coil C2. An end of the first unit coil C1 on the first side (+R side) in the R direction of the fourth conductor W4 in the second section S2 is connected to an end of the second unit coil C2 on the first side (+R side) in the R direction of the first conductor W1 in the first section S1. In this case as well, dielectric breakdown at both ends of the winding portion 4 in the R direction is suppressed.

[0036] In the modified winding portion 4 shown in Fig. 3, the +R side corresponds to the first side in the R direction, and the -R side corresponds to the second side in the R direction. However, the winding portion 4 of the modified example may be reversed in the R direction. In this case, the -R side corresponds to the first side in the R direction, and the +R side corresponds to the second side in the R direction. In this case, too, dielectric breakdown at both ends of the winding portion 4 in the R direction is suppressed.

[0037] According to at least one of the embodiments described above, the number of turns of the second conductor W2 in the first section S1 is one turn less than the number of turns of the first conductor W1 in the winding portion 4. This makes it possible to suppress dielectric breakdown at both ends of the winding portion 4 in the R direction.

[0038] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents. [Explanation of symbols]

[0039] C1...first unit coil, C2...second unit coil, SP...spacer, S1...first section, S2...second section, W1...first conductor, W2...second conductor, W3...third conductor, W4...fourth conductor, 1...static induction coil, 2...iron core, 4...winding section.

Claims

1. a core and a winding portion arranged coaxially with the core, the winding portion has unit coils arranged in the axial direction of the iron core, The unit coil has a pair of sections aligned in the axial direction of the iron core, the pair of sections includes a first section disposed on a first side in the axial direction and a second section disposed on a second side in the axial direction that is opposite to the first side in the axial direction, the first section and the second section are formed by winding a pair of conductors adjacent to each other in the radial direction of the core, the pair of conductors in the first section includes, at an end portion on the first side in the radial direction, a first conductor arranged on the first side in the radial direction and a second conductor arranged on a second side in the radial direction that is opposite to the first side in the radial direction, the pair of conductors in the second section includes, at an end portion on the first side in the radial direction, a third conductor arranged on the first side in the radial direction and a fourth conductor arranged on the second side in the radial direction; the number of turns of the second conductor in the first section is one less than the number of turns of the first conductor; an end portion of the first conductor in the first section on the second side in the radial direction and an end portion of the third conductor in the second section on the second side in the radial direction are connected to each other; an end portion of the third conductor in the second section on a first side in the radial direction is connected to an end portion of the second conductor in the first section on a first side in the radial direction; an end portion of the second conductor in the first section on the second side in the radial direction and an end portion of the fourth conductor in the second section on the second side in the radial direction are connected to each other; When the unit coil arranged on a first side in the axial direction is a first unit coil, and the unit coil arranged on a second side in the axial direction of the first unit coil is a second unit coil, an end portion of the fourth conductor in the second section of the first unit coil on the first side in the radial direction is connected to an end portion of the first conductor in the first section of the second unit coil on the first side in the radial direction; Stationary induction appliance.

2. the first section has a spacer between the pair of adjacent conductors, the spacer corresponding to one turn of the second conductor; the spacer is formed of an electrically insulating material; The static induction electric appliance according to claim 1.

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