JP2018032847A - Stationary induction equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress electric field concentration at the outer peripheral side and inner peripheral side ends of an electrostatic shield while suppressing the thickening of the electrostatic shield. SOLUTION: An iron core, a winding wound around the iron core, and an annular electrostatic shield 150 arranged adjacent to at least one of the ends of the winding in a direction along the central axis. Be prepared. The electrostatic shield 150 includes a conductor portion 152 and a second insulating coating portion 153 that covers the conductor portion 152. The potential of the electrostatic shield 150 is lower than the highest potential in the winding. [Selection diagram] Fig. 5

Description

  The present invention relates to a stationary induction device, and more particularly, to a stationary induction device including an electrostatic shield.

  When an impact voltage such as a lightning surge enters a static induction device such as a transformer or a reactor, the potential distribution in the winding becomes steep compared to the potential distribution proportional to the number of turns, and then proportional to the number of turns. Oscillate around the potential distribution. This phenomenon is called potential oscillation. When the amplitude of the potential oscillation is large, a large potential difference may occur between adjacent wires in the winding and between adjacent windings, which may cause dielectric breakdown. When an electrostatic shield is installed adjacent to the winding, the capacitance between the windings is larger than the capacitance between the winding and the ground, reducing the amplitude of the potential oscillation. Is done.

  In a transformer including a conventional electrostatic shield, electrostatic shields are provided at both ends in the central axis direction of the winding. Each of the outer peripheral end and the inner peripheral end of the electrostatic shield is a curved surface. The electrostatic shield is fastened and fixed to the winding in the central axis direction of the winding, and has a width equivalent to the width of the winding in the radial direction of the winding (see, for example, Patent Document 1). ).

Japanese Utility Model Publication No. 60-113614

  In an electrostatic shield of a conventional transformer, there is a portion where an electric field concentrates on an outer peripheral end and an inner peripheral end on the side opposite to the side adjacent to the coil. When the radius of curvature of each of the outer edge and inner edge of the electrostatic shield is increased to suppress electric field concentration at the outer edge and inner edge of the electrostatic shield As a result, the electrostatic shield becomes thicker and the static induction device becomes larger.

  The present invention has been made to solve the above-described problems, and suppresses electric field concentration at the outer peripheral end and the inner peripheral end of the electrostatic shield while suppressing the electrostatic shield from becoming thick. An object of the present invention is to provide a static induction device that can be used.

  A stationary induction device according to the present invention has a pair of at least one of an iron core, at least one winding wound around the iron core as a central axis, and at least one end of the at least one winding in a direction along the central axis. 1 and an annular at least one electrostatic shield arranged correspondingly adjacent to each other. The at least one winding includes an electric wire portion and a first insulating covering portion that covers the electric wire portion. The at least one electrostatic shield includes a conductor portion and a second insulation coating portion that covers the conductor portion. The potential of the at least one electrostatic shield is lower than the highest potential in the at least one winding.

  ADVANTAGE OF THE INVENTION According to this invention, the electric field concentration in the edge part of the outer peripheral side of an electrostatic shield and the edge part of an inner peripheral side can be suppressed, suppressing that an electrostatic shield becomes thick.

It is a perspective view which shows the external appearance of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 1 of this invention. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 1 of this invention, Comprising: It is the figure seen from the II-II line arrow direction of FIG. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 1 of this invention, Comprising: It is the figure seen from the III-III line arrow direction of FIG. FIG. 4 is an exploded perspective view of the stationary induction device according to the first embodiment of the present invention, as viewed from the direction of arrow IV in FIG. 3. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 1 of this invention, Comprising: It is a figure which expands and shows the V section of FIG. It is sectional drawing which shows the electrical connection form of the electrostatic shield of the static induction apparatus which concerns on the 1st modification of Embodiment 1 of this invention. It is sectional drawing which shows the electrical connection form of the electrostatic shield of the static induction apparatus which concerns on the 2nd modification of Embodiment 1 of this invention. It is a perspective view which shows the external appearance of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 2 of this invention. It is a partial cross section figure of the static induction apparatus which concerns on Embodiment 2 of this invention. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 2 of this invention, Comprising: It is a figure which expands and shows the X section of FIG. It is a perspective view which shows the external appearance of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 3 of this invention. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 3 of this invention, Comprising: It is the figure seen from the XII-XII line arrow direction of FIG. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 3 of this invention, Comprising: It is the figure seen from the XIII-XIII line arrow direction of FIG. It is sectional drawing of the stationary induction | guidance | derivation apparatus which concerns on Embodiment 3 of this invention, Comprising: It is a figure which expands and shows the XIV part of FIG.

  Hereinafter, stationary induction devices according to embodiments of the present invention will be described with reference to the drawings. In the description of the following embodiments, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

Embodiment 1 FIG.
FIG. 1 is a perspective view showing an appearance of a stationary induction device according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of the stationary induction device according to the first embodiment of the present invention, as viewed from the direction of arrows II-II in FIG. FIG. 3 is a cross-sectional view of the stationary induction device according to the first embodiment of the present invention, as viewed from the direction of arrows III-III in FIG. 4 is an exploded perspective view of the stationary induction device according to the first embodiment of the present invention, as viewed from the direction of arrow IV in FIG. FIG. 5 is a cross-sectional view of the stationary induction device according to the first embodiment of the present invention, and is an enlarged view of a V portion in FIG. 3. In FIG. 1, the electrostatic shield is not shown. In FIG. 4, the iron core is not shown.

  As shown in FIGS. 1-5, the stationary induction apparatus 100 which concerns on Embodiment 1 of this invention is an internal iron type transformer. The stationary induction device 100 includes an iron core 110 and a low-voltage winding 120 and a high-voltage winding 130 wound concentrically around the main leg portion of the iron core 110 as a central axis. That is, the static induction device 100 includes a plurality of windings.

The stationary induction device 100 further includes a tank (not shown). The tank is filled with insulating oil or insulating gas, which is an insulating medium and a cooling medium. The insulating oil is, for example, mineral oil, ester oil or silicon oil. The insulating gas is, for example, SF ₆ gas or dry air. The iron core 110, the low voltage winding 120, and the high voltage winding 130 are accommodated in a tank.

  The high voltage winding 130 is located outside the low voltage winding 120. The high-voltage winding 130 is configured by laminating a plurality of disk-shaped windings formed by winding a flat electric wire 140 in a disk shape in a direction along the central axis. The flat electric wire 140 includes a wire portion 141 having a substantially rectangular shape in cross section and a first insulation coating portion 142 that covers the wire portion 141. Although not shown, the low voltage winding 120 has the same configuration as the high voltage winding 130.

  The stationary induction device 100 further includes an annular electrostatic shield 150 disposed adjacent to each end of the low voltage winding 120 and the high voltage winding 130 in the direction along the central axis. In the present embodiment, the electrostatic shield 150 is arranged adjacent to both ends of each of the low-voltage winding 120 and the high-voltage winding 130 on a one-to-one basis, but this is not limitative. However, it is sufficient that the low voltage winding 120 and the high voltage winding 130 are arranged adjacent to each other in a one-to-one correspondence with at least one of the end portions. Each of the four electrostatic shields 150 included in the static induction device 100 has an electric field concentration at the end in the direction along the central axis of each of the low-voltage winding 120 and the high-voltage winding 130 in addition to reducing the amplitude of the potential oscillation. It is installed to alleviate

  Each of the four electrostatic shields 150 includes an insulator part 151, a conductor part 152, and a second insulation coating part 153 that covers the conductor part 152. In the present embodiment, conductor portion 152 is provided so as to cover the surface of insulator portion 151. However, the portion of the insulator 151 may be constituted by the conductor 152. That is, the electrostatic shield 150 may be composed of the conductor portion 152 and the second insulating coating portion 153.

  Each conductor 152 of the four electrostatic shields 150 is provided with one or more cuts so as to be discontinuous in the circumferential direction. By this break, it is possible to prevent a current circulating around the entire circumference of the electrostatic shield 150 from flowing. In the present embodiment, each insulator portion 151 of the four electrostatic shields 150 is not provided with a cut, but may be provided at the same position as the conductor portion 152. In this case, both end surfaces of the conductor portion 152 in the circumferential direction are covered with the second insulating coating portion 153.

  The insulator 151 is made of a press board or reinforced wood. Reinforced wood is wood whose strength has been increased by compression molding or resin injection. The conductor 152 is made of a wire mesh, metal foil, conductive tape, or conductive paint. The second insulating coating portion 153 is made of press board or polyethylene terephthalate.

  In order to reduce the amplitude of the potential oscillation, when the impact voltage enters the stationary induction device 100, the electrostatic shield 150 causes fluctuations in the potential of the low voltage winding 120 or the high voltage winding 130 adjacent to the electrostatic shield 150. It is necessary to follow. When the electrical resistivity of the conductor part 152 is high, the follow-up of the potential of the electrostatic shield 150 becomes slow, and the potential vibration may not be sufficiently suppressed. Therefore, it is preferable that the surface resistivity of the conductor portion 152 is 10Ω / sq or more and 50Ω / sq or less.

  Each of the outer peripheral end and the inner peripheral end of the electrostatic shield 150 is a curved surface. In the present embodiment, each of the outer peripheral end and the inner peripheral end of the electrostatic shield 150 is formed by a curved surface in which two circular arc portions having different curvature radii in a cross section are continuous. Specifically, each of the outer peripheral end portion and the inner peripheral end portion of the insulator 151 is configured by a curved surface in which a circular arc portion having a radius of curvature r1 and an arc portion having a radius of curvature r2 are continuous in a cross section. Each of the conductor portion 152 and the second insulating covering portion 153 has an outer shape that is substantially similar to the outer shape of the insulator portion 151.

  The curvature radius r2 is larger than the curvature radius r1. In the electrostatic shield 150, the arc portion having the curvature radius r 1 is provided on the winding side adjacent to the electrostatic shield 150, and the arc portion having the curvature radius r 2 is opposite to the winding side adjacent to the electrostatic shield 150. Is provided.

  In the radial direction perpendicular to the direction along the central axis, the width W2 of the electrostatic shield 150 is equal to the width W1 of the winding adjacent to the electrostatic shield 150. That is, the width W2 of the electrostatic shield 150 adjacent to the low voltage winding 120 is equal to the width W1 of the low voltage winding 120. The width W2 of the electrostatic shield 150 adjacent to the high voltage winding 130 is equal to the width W1 of the high voltage winding 130.

  The width W1 of each of the low-voltage winding 120 and the high-voltage winding 130 is such that the radially outer side of the central axis extends from the inner peripheral end of the first insulation coating portion 142 of the rectangular electric wire 140 located on the innermost periphery. Toward the outer peripheral side end of the first insulation coating portion 142 of the flat electric wire 140 located on the outermost periphery. Further, the width W2 of the electrostatic shield 150 is such that the electrostatic shield 150 extends from the outer surface of the second insulating coating portion 153 located at the inner peripheral end of the electrostatic shield 150 toward the radially outer side of the central axis. This is the width between the outer surface of the second insulating coating 153 located at the outer peripheral end of 150.

  Equivalent to the winding width W1 is in the range of 90% to 110% of the winding width W1. Since the winding width W1 is equal to the width W2 of the electrostatic shield 150, the electric field at each of the winding-side end of the winding and the winding-side end of the electrostatic shield 150 is the same. Concentration can be suppressed, and the insulation performance of the stationary induction device 100 can be enhanced.

  The second insulation coating portion 153 includes an inner portion 153a facing the low voltage winding 120 or the high voltage winding 130 adjacent in the direction along the central axis, and the low voltage winding 120 or the high voltage winding adjacent in the direction along the central axis. The outer part 153b located on the opposite side to the line 130 is included. The inner part 153a is thicker than the outer part 153b. In the second insulation coating portion 153, the portion constituting the outer peripheral end portion and inner peripheral end portion of the electrostatic shield 150 located between the outer portion 153b and the inner portion 153a is the thickness of the inner portion 153a. And a thickness greater than or equal to the thickness of the outer portion 153b.

  In the present embodiment, the static induction device 100 includes the wiring 160 that electrically connects the conductor portion 152 of the electrostatic shield 150 and the electric wire portion 141 at the end of the winding adjacent to the electrostatic shield 150. It has more. As shown in FIG. 5, the wiring 160 is connected to a portion located between the innermost periphery and the outermost periphery in the electric wire portion 141 at the end of the winding adjacent to the electrostatic shield 150. The wiring 160 includes a core wire 161 and a third insulation coating portion 162 that covers the core wire 161.

  Specifically, the conductor 152 of the electrostatic shield 150 adjacent to the low voltage winding 120 is connected between the innermost circumference and the outermost circumference in the flat electric wire 140 located at the end of the low voltage winding 120 by the wiring 160. It is connected to the electric wire portion 141 located. As a result, the conductor portion 152 of the electrostatic shield 150 and the electric wire portion 141 located between the innermost circumference and the outermost circumference in the flat electric wire 140 located at the end of the low voltage winding 120 have the same potential. Yes. The conductor portion 152 of the electrostatic shield 150 adjacent to the high voltage winding 130 is connected to the wire portion 141 located between the innermost periphery and the outermost periphery of the flat electric wire 140 positioned at the end of the high voltage winding 130 by the wiring 160. Connected with. As a result, the conductor portion 152 of the electrostatic shield 150 and the electric wire portion 141 located between the innermost circumference and the outermost circumference in the flat electric wire 140 located at the end of the high voltage winding 130 have the same potential. Yes.

  Generally, the highest voltage is applied to the plurality of windings of the stationary induction device 100 in the electric wire portion 141 located on the innermost or outermost circumference of the flat electric wire 140 located at the end of the high-voltage winding 130. It becomes the input terminal. Usually, the conductor portion 152 of the electrostatic shield 150 adjacent to the high voltage winding 130 is connected to the input end to have the same potential.

  In the flat electric wire 140 located at the end of the high-voltage winding 130, the electric potential of the electric wire portion 141 located between the innermost circumference and the outermost circumference is lower than the highest potential in the plurality of windings included in the stationary induction device 100. It becomes. In the static induction device 100 according to the present embodiment, the conductor portion 152 of the electrostatic shield 150 is positioned between the innermost periphery and the outermost periphery in the wire portion 141 at the end of the winding adjacent to the electrostatic shield 150. It is connected to the part. As a result, the conductor portion 152 of the electrostatic shield 150 has the same potential as the electric wire portion 141 located between the innermost circumference and the outermost circumference in the flat electric wire 140 located at the end of the high voltage winding 130. The potential is lower than the highest potential in the plurality of windings included in the stationary induction device 100. In addition, each of the plurality of electrostatic shields 150 has a one-to-one correspondence and is lower than the highest potential in adjacent windings.

  As a result, in the static induction device 100 according to the present embodiment, the ground potential of the electrostatic shield 150 can be lowered as compared with the case where the conductor portion 152 of the electrostatic shield 150 is connected to the input terminal. Thereby, the electric field in the outer peripheral side edge part and inner peripheral side edge part of the electrostatic shield 150 can be reduced. In the static induction device 100 according to the present embodiment, there is no need to increase the thickness of the electrostatic shield 150. That is, in the static induction device 100, it is possible to suppress the electric field concentration at the outer peripheral end and the inner peripheral end of the electrostatic shield 150 while suppressing the electrostatic shield 150 from becoming thick.

  As shown in FIG. 5, in this embodiment, the wiring 160 is connected to the outer peripheral portion of the outer surface of the conductor portion 152, but the present invention is not limited to this, and the wiring is connected to the inner peripheral portion of the outer surface of the conductor portion 152. 160 may be connected. In order to further ensure the insulation performance between the wiring 160 and the winding, the conductor portion 152 has a potential difference between the adjacent windings of the inner and outer peripheral portions on the outer surface of the conductor portion 152. The smaller one is preferably connected to the wiring 160. For the same reason, it is preferable that the wiring 160 be disposed along the surface of the second insulating coating portion 153 of the electrostatic shield 150.

  When connecting the wiring 160 to the electrostatic shield 150, a part of the second insulation coating portion 153 of the electrostatic shield 150 is removed to expose the conductor portion 152, and the core wire 161 is soldered to the exposed portion of the conductor portion 152. Connect by brazing or silver brazing. This connection portion is covered with insulating paper. When connecting the wiring 160 to the winding, a part of the first insulating coating portion 142 of the flat electric wire 140 is removed to expose the electric wire portion 141, and the core wire 161 is soldered to the exposed portion of the electric wire portion 141 or silver. Connect by brazing. This connection portion is covered with insulating paper.

  In the static induction device 100 according to the present embodiment, since the relative dielectric constant of the material constituting the second insulating coating portion 153 is higher than the relative dielectric constant of the material constituting the insulating medium, The capacitance between the winding adjacent to the shield 150 can be increased. Thereby, when an impact voltage such as a lightning surge enters the stationary induction device 100, the potential difference generated between the adjacent wires in the winding adjacent to the electrostatic shield 150 can be reduced, and as a result. The amplitude of potential oscillation can be reduced.

  Further, in the second insulation coating portion 153 of the electrostatic shield 150, the inner portion 153a is thicker than the outer portion 153b, so that the insulation between the electrostatic shield 150 and the winding adjacent to the electrostatic shield 150 is increased. be able to. Thereby, the insulation reliability of the stationary induction device 100 can be improved.

  In addition, the electrical connection form for making the electric potential of the electrostatic shield 150 lower than the electric potential of the input terminal is not limited to the above. Here, the modification of the electrical connection form of an electrostatic shield is demonstrated. FIG. 6 is a cross-sectional view showing an electrical connection configuration of the electrostatic shield of the stationary induction device according to the first modification of the first embodiment of the present invention. FIG. 7 is a cross-sectional view showing an electrical connection configuration of the electrostatic shield of the stationary induction device according to the second modification of the first embodiment of the present invention. 6 and 7 are shown in the same cross-sectional view as FIG.

  As shown in FIG. 6, the conductor 152 of the electrostatic shield 150 of the static induction device according to the first modification of the first embodiment of the present invention is electrically connected to the electric wire 141 other than the end of the adjacent winding. It is connected to the. As a result, the conductor portion 152 of the electrostatic shield 150 has the same potential as the electric wire portion 141 other than the end portion of the adjacent winding. The electric potential of the electric wire portion 141 other than the end portion of the winding adjacent to the electrostatic shield 150 is lower than the highest potential in the plurality of windings provided in the stationary induction device according to the first modification.

  As a result, in the static induction device according to the first modification, the ground potential of the electrostatic shield 150 can be lowered as compared with the case where the conductor portion 152 of the electrostatic shield 150 is connected to the input terminal. Thereby, the electric field in the outer peripheral side edge part and inner peripheral side edge part of the electrostatic shield 150 can be reduced. Even in the static induction device according to the first modification, there is no need to make the electrostatic shield 150 thick. That is, also in the static induction device according to the first modification, it is possible to suppress the electric field concentration at the outer peripheral end and the inner peripheral end of the electrostatic shield 150 while suppressing the electrostatic shield 150 from becoming thick. .

  In the static induction device according to the first modified example, the conductor portion 152 of the electrostatic shield 150 is connected to either the innermost periphery or the outermost periphery other than the end of the winding adjacent to the electrostatic shield 150. It may be.

  In other words, the conductor portion 152 of the electrostatic shield 150 adjacent to the low voltage winding 120 is the wire portion 141 located on the innermost circumference or the outermost circumference in the flat electric wire 140 located on the wiring 160 other than the end portion of the low voltage winding 120. Are connected to each other, and the conductor portion 152 of the electrostatic shield 150 and the electric wire portion 141 located on the innermost or outermost periphery of the flat electric wire 140 located outside the end of the low voltage winding 120 have the same potential. It may be. The conductor portion 152 of the electrostatic shield 150 adjacent to the high-voltage winding 130 is connected to the electric wire portion 141 located on the innermost or outermost circumference of the flat electric wire 140 located at a position other than the end of the high-voltage winding 130 by the wiring 160. The conductor portion 152 of the electrostatic shield 150 and the wire portion 141 located on the innermost or outermost periphery of the flat electric wire 140 located at a position other than the end of the high-voltage winding 130 are at the same potential. Also good. In this case, the connection between the wiring 160 and the electric wire portion 141 is easy, and the stationary induction device according to the first modification can be easily assembled as compared to the stationary induction device 100 according to the first embodiment.

  As shown in FIG. 7, the conductor 152 of the electrostatic shield 150 of the static induction device according to the second modification of the first embodiment of the present invention is electrically floating. That is, the static induction device according to the second modification does not include the wiring 160, and the conductor portion 152 of the electrostatic shield 150 is not electrically connected to the wire portion 141 of the winding.

  The ground potential of the conductor portion 152 of the electrostatic shield 150 of the static induction device according to the second modification of the first embodiment of the present invention includes the electrostatic shield 150, the winding adjacent to the electrostatic shield 150, and the iron core 110. It depends on the positional relationship. That is, the electrostatic capacity between the electrostatic shield 150 and the winding adjacent to the electrostatic shield 150 is defined by these positional relationships, and the conductor part 152 of the electrostatic shield 150 is defined by the defined electrostatic capacity. The ground potential is determined.

  Even in the static induction device according to the second modification, the ground potential of the electrostatic shield 150 can be lowered as compared with the case where the conductor portion 152 of the electrostatic shield 150 is connected to the input end. Thereby, the electric field in the outer peripheral side edge part and inner peripheral side edge part of the electrostatic shield 150 can be reduced. Also in the static induction device according to the second modification, there is no need to make the electrostatic shield 150 thick. That is, also in the static induction device according to the second modification, it is possible to suppress the electric field concentration at the outer peripheral end and the inner peripheral end of the electrostatic shield 150 while suppressing the electrostatic shield 150 from becoming thick. .

Embodiment 2. FIG.
Hereinafter, a stationary induction device according to Embodiment 2 of the present invention will be described. Note that the static induction device according to the present embodiment is mainly different in that it is a shell-type transformer, and therefore, the description of the same configuration as that of the static induction device according to Embodiment 1 will not be repeated.

  FIG. 8 is a perspective view showing an appearance of a stationary induction device according to Embodiment 2 of the present invention. FIG. 9 is a partial cross-sectional view of a stationary induction device according to Embodiment 2 of the present invention. FIG. 10 is a cross-sectional view of the stationary induction device according to the second embodiment of the present invention, and is an enlarged view of a portion X in FIG. In FIG. 8, the electrostatic shield is not shown. In FIG. 9, only the upper side of the iron core is shown.

  As shown in FIGS. 8 to 10, stationary induction device 200 according to Embodiment 2 of the present invention is an outer iron type transformer. The stationary induction device 200 includes an iron core 210, and a low-voltage winding 220 and a high-voltage winding 230 that are wound around the main leg portion of the iron core 210 as a central axis and arranged coaxially.

The stationary induction device 200 further includes a tank 270. The tank 270 is filled with insulating oil or insulating gas, which is an insulating medium and a cooling medium. The insulating oil is, for example, mineral oil, ester oil or silicon oil. The insulating gas is, for example, SF ₆ gas or dry air. The iron core 210, the low voltage winding 220 and the high voltage winding 230 are accommodated in the tank 270.

  In the direction along the central axis, the high voltage winding 230 is disposed so as to be sandwiched between the low voltage windings 220. The high-voltage winding 230 is configured by laminating a plurality of unit windings formed by winding a rectangular electric wire 240 in a racetrack shape in the axial direction of the central axis. The flat electric wire 240 includes a substantially rectangular electric wire portion 241 and a first insulating covering portion 242 that covers the electric wire portion 241 in cross section. Although not shown, the low voltage winding 220 has the same configuration as the high voltage winding 230.

  The static induction device 200 further includes a plurality of annular electrostatic shields 250 disposed adjacent to the ends of the low voltage winding 220 and the high voltage winding 230 in the direction along the central axis. In FIG. 9, only one electrostatic shield 250 adjacent to the high voltage winding 230 is shown.

  Each of the four electrostatic shields 250 includes an insulator part 251, a conductor part 252, and a second insulation coating part 253 that covers the conductor part 252. In the present embodiment, the conductor portion 252 is provided so as to cover the surface of the insulator portion 251. However, the portion of the insulator portion 251 may be configured by the conductor portion 252. That is, the electrostatic shield 250 may be composed of the conductor portion 252 and the second insulating coating portion 253.

  Each conductor portion 252 of the four electrostatic shields 250 is provided with one or more cuts so as to be discontinuous in the circumferential direction. Due to this break, it is possible to prevent a current circulating through the entire circumference of the electrostatic shield 250 from flowing. In the present embodiment, each insulator portion 251 of the four electrostatic shields 250 is not provided with a cut, but a cut may be provided at the same position as the cut of the conductor portion 252. In this case, both end surfaces in the circumferential direction of the conductor portion 252 are covered with the second insulating coating portion 253.

  The insulator 251 is made of a press board or a reinforced wood. The conductor portion 252 is made of a wire mesh, metal foil, conductive tape, or conductive paint. The second insulating coating portion 253 is made of press board or polyethylene terephthalate.

  In order to reduce the amplitude of the potential oscillation, when the impact voltage enters the stationary induction device 200, the electrostatic shield 250 causes fluctuations in the potential of the low voltage winding 220 or the high voltage winding 230 adjacent to the electrostatic shield 250. It is necessary to follow. When the electrical resistivity of the conductor part 252 is high, the follow-up of the potential of the electrostatic shield 250 is delayed, and the potential vibration may not be sufficiently suppressed. Therefore, it is preferable that the surface resistivity of the conductor part 252 is 10Ω / sq or more and 50Ω / sq or less.

  Each of the outer peripheral end and the inner peripheral end of the electrostatic shield 250 is formed of a curved surface. In the present embodiment, each of the outer peripheral end portion and the inner peripheral end portion of the electrostatic shield 250 is configured by a semicircular curved surface in a cross section. Specifically, each of the outer peripheral end portion and the inner peripheral end portion of the insulator portion 251 is formed by a semicircular curved surface having a radius r3 in the cross section, and the conductor portion 252 and the second end portion. Each of the insulating coating portions 253 has an outer shape that is substantially similar to the outer shape of the insulator portion 251.

  In the radial direction of the central axis, the width W2 of the electrostatic shield 250 is equal to the width W1 of the winding adjacent to the electrostatic shield 250. That is, the width W2 of the electrostatic shield 250 adjacent to the low voltage winding 220 is equal to the width W1 of the low voltage winding 220. The width W 2 of the electrostatic shield 250 adjacent to the high voltage winding 230 is equal to the width W 1 of the high voltage winding 230.

  The width W1 of each of the low-voltage winding 220 and the high-voltage winding 230 is such that the radially outer side of the central axis extends from the inner peripheral end of the first insulating coating portion 242 of the rectangular electric wire 240 located on the innermost periphery. Toward the outer peripheral side end of the first insulation coating portion 242 of the flat electric wire 240 located on the outermost periphery. Further, the width W2 of the electrostatic shield 250 is such that the electrostatic shield 250 extends from the outer surface of the second insulating coating portion 253 located at the inner peripheral end of the electrostatic shield 250 toward the radially outer side of the central axis. This is the width between the outer surface of the second insulation coating portion 253 located at the outer peripheral end of 250.

  Equivalent to the winding width W1 is in the range of 90% to 110% of the winding width W1. Since the width W1 of the winding and the width W2 of the electrostatic shield 250 are equal, the electric field at each of the end of the winding on the electrostatic shield 250 side and the end of the electrostatic shield 250 on the winding side. Concentration can be suppressed, and the insulation performance of the stationary induction device 200 can be enhanced.

  The second insulation coating portion 253 includes an inner portion 253a facing the adjacent low voltage winding 220 or high voltage winding 230 in the direction along the central axis, and the low voltage winding 220 or high voltage winding adjacent in the direction along the central axis. The outer part 253b located on the opposite side to the line 230 is included. The inner part 253a is thicker than the outer part 253b. In the second insulating coating portion 253, the portion constituting the outer peripheral side end portion and the inner peripheral side end portion of the electrostatic shield 250 located between the outer side portion 253b and the inner side portion 253a is the thickness of the inner side portion 253a. And a thickness greater than or equal to the thickness of the outer portion 253b.

  In the present embodiment, the static induction device 200 includes a wiring 260 that electrically connects the conductor portion 252 of the electrostatic shield 250 and the electric wire portion 241 at the end of the winding adjacent to the electrostatic shield 250. It has more. As shown in FIG. 10, the wiring 260 is connected to a portion located between the innermost periphery and the outermost periphery in the electric wire portion 241 at the end of the winding adjacent to the electrostatic shield 250. The wiring 260 is constituted by a core wire 261 and a third insulation coating portion 262 that covers the core wire 261.

  Specifically, the conductor portion 252 of the electrostatic shield 250 adjacent to the low voltage winding 220 is connected between the innermost circumference and the outermost circumference in the rectangular electric wire 240 located at the end of the low voltage winding 220 by the wiring 260. It is connected to the electric wire portion 241 located. As a result, the conductor portion 252 of the electrostatic shield 250 and the electric wire portion 241 located between the innermost circumference and the outermost circumference in the flat electric wire 240 located at the end of the low voltage winding 220 have the same potential. Yes. The conductor portion 252 of the electrostatic shield 250 adjacent to the high-voltage winding 230 has a wire portion 241 located between the innermost circumference and the outermost circumference in the flat electric wire 240 located at the end of the high-voltage winding 230 by the wiring 260. Connected with. As a result, the conductor portion 252 of the electrostatic shield 250 and the electric wire portion 241 located between the innermost circumference and the outermost circumference in the flat electric wire 240 located at the end of the high voltage winding 230 have the same potential. Yes.

  Generally, the highest voltage is applied to the plurality of windings of the stationary induction device 200 in the electric wire portion 241 located on the innermost or outermost circumference of the flat electric wire 240 located at the end of the high-voltage winding 230. It becomes the input terminal. Normally, the conductor portion 252 of the electrostatic shield 250 adjacent to the high voltage winding 230 is connected to the input end, and the rectangular electric wire 240 positioned at the end portion of the conductor portion 252 of the electrostatic shield 250 and the high voltage winding 230 is connected. , The electric wire portion 241 located on the innermost periphery or the outermost periphery has the same potential.

  In the flat electric wire 240 located at the end of the high-voltage winding 230, the electric potential of the electric wire portion 241 located between the innermost circumference and the outermost circumference is lower than the highest potential in the plurality of windings included in the stationary induction device 200. It becomes. In the static induction device 200 according to the present embodiment, the conductor portion 252 of the electrostatic shield 250 is positioned between the innermost periphery and the outermost periphery in the electric wire portion 241 at the end of the winding adjacent to the electrostatic shield 250. The conductor portion 252 of the electrostatic shield 250 and the portion located between the innermost periphery and the outermost periphery in the wire portion 241 at the end of the winding adjacent to the electrostatic shield 250, The electric potential is the same, and the electric potential is lower than the highest electric potential in the plurality of windings included in the stationary induction device 200. Each potential of the plurality of electrostatic shields 250 is one-to-one corresponding to a potential lower than the highest potential in adjacent windings.

  As a result, in the static induction device 200 according to the present embodiment, the ground potential of the electrostatic shield 250 can be lowered as compared with the case where the conductor portion 252 of the electrostatic shield 250 is connected to the input end. Thereby, the electric field in the outer peripheral side edge part and inner peripheral side edge part of the electrostatic shield 250 can be reduced. In the static induction device 200 according to the present embodiment, there is no need to increase the thickness of the electrostatic shield 250. That is, in the static induction device 200, it is possible to suppress the electric field concentration at the outer peripheral end and the inner peripheral end of the electrostatic shield 250 while suppressing the electrostatic shield 250 from becoming thick.

  As shown in FIG. 10, in the present embodiment, the wiring 260 is connected to the outer peripheral portion of the outer surface of the conductor portion 252, but the present invention is not limited thereto, and the wiring is connected to the inner peripheral portion of the outer surface of the conductor portion 252. 260 may be connected. In order to further ensure the insulation performance between the wiring 260 and the winding, the conductor portion 252 has a potential difference between the adjacent windings of the inner and outer peripheral portions on the outer surface of the conductor portion 152. The smaller one is preferably connected to the wiring 260. For the same reason, it is preferable that the wiring 260 is disposed along the surface of the second insulating coating portion 253 of the electrostatic shield 250.

  When connecting the wiring 260 to the electrostatic shield 250, a part of the second insulation coating portion 253 of the electrostatic shield 250 is removed to expose the conductor portion 252, and the core wire 261 is soldered to the exposed portion of the conductor portion 252. Connect by brazing or silver brazing. This connection portion is covered with insulating paper. When connecting the wiring 260 to the winding, a part of the first insulation coating portion 242 of the flat wire 240 is removed to expose the wire portion 241, and the core wire 261 is soldered to the exposed portion of the wire portion 241 or silver Connect by brazing. This connection portion is covered with insulating paper.

  In the static induction device 200 according to the present embodiment, since the relative dielectric constant of the material constituting the second insulating coating portion 253 is higher than the relative dielectric constant of the material constituting the insulating medium, The capacitance between the winding adjacent to the shield 250 can be increased. Thereby, when an impact voltage such as a lightning surge enters the stationary induction device 200, the potential difference generated between the adjacent wires in the winding adjacent to the electrostatic shield 250 can be reduced. The amplitude of potential oscillation can be reduced.

  Further, in the second insulating covering portion 253 of the electrostatic shield 250, the inner portion 253a is thicker than the outer portion 253b, so that the insulation between the electrostatic shield 250 and the winding adjacent to the electrostatic shield 250 is increased. be able to. Thereby, the insulation reliability of the stationary induction device 200 can be improved.

  The electrical connection form of the electrostatic shield 250 is not limited to the above, and is the same as the electrical connection form of the first modified example or the second modified example described in the first embodiment. Also good.

Embodiment 3 FIG.
Hereinafter, a stationary induction device according to Embodiment 3 of the present invention will be described. The stationary induction device according to the present embodiment is mainly different in that it is an inner iron type reactor, and therefore, the description of the same configuration as that of the stationary induction device according to Embodiment 1 will not be repeated.

  FIG. 11 is a perspective view showing an appearance of a stationary induction device according to Embodiment 3 of the present invention. 12 is a cross-sectional view of the stationary induction device according to the third embodiment of the present invention, as viewed from the direction of arrows XII-XII in FIG. FIG. 13 is a cross-sectional view of the stationary induction device according to the third embodiment of the present invention, as viewed from the direction of arrows XIII-XIII in FIG. FIG. 14 is a cross-sectional view of the stationary induction device according to the third embodiment of the present invention, and is an enlarged view of the XIV portion of FIG. In FIG. 11, the electrostatic shield is not shown.

  As shown in FIGS. 11 to 14, stationary induction device 300 according to Embodiment 3 of the present invention is an inner iron type reactor. The stationary induction device 300 includes an iron core 310 and a winding 320 wound concentrically around the main leg portion of the iron core 310 as a central axis. That is, the static induction device 300 includes one winding.

  The winding 320 is configured by laminating a plurality of disk-shaped windings formed by winding a flat electric wire 340 in a disk shape in a direction along the central axis. The flat electric wire 340 includes a substantially rectangular electric wire portion 341 and a first insulating covering portion 342 that covers the electric wire portion 341 in a cross section.

  The stationary induction device 300 further includes an annular electrostatic shield 350 disposed adjacent to the end of the winding 320 in the direction along the central axis. In the present embodiment, the electrostatic shield 350 is arranged adjacent to both ends of the winding 320 in a one-to-one correspondence. However, the present invention is not limited to this, and the end of the winding 320 is not limited thereto. It suffices if it is arranged adjacent to at least one of the above. Each of the two electrostatic shields 350 included in the static induction device 300 is installed in order to reduce electric field concentration at the end in the direction along the central axis of the winding 320 in addition to reducing the amplitude of the potential vibration. ing.

  Each of the two electrostatic shields 350 includes an insulator portion 351, a conductor portion 352, and a second insulation coating portion 353 that covers the conductor portion 352. In the present embodiment, the conductor portion 352 is provided so as to cover the surface of the insulator portion 351. However, the insulator portion 351 may be constituted by the conductor portion 352. That is, the electrostatic shield 350 may be composed of the conductor portion 352 and the second insulating coating portion 353.

  Each conductor part 352 of the two electrostatic shields 350 is provided with one or more cuts so as to be discontinuous in the circumferential direction. Due to this break, it is possible to prevent a current circulating around the entire circumference of the electrostatic shield 350 from flowing. In this embodiment, each insulator portion 351 of the two electrostatic shields 350 is not provided with a cut, but a cut may be provided at the same position as the conductor portion 352. In this case, both end surfaces of the conductor portion 352 in the circumferential direction are covered with the second insulating coating portion 353.

  Each of the outer peripheral end and the inner peripheral end of the electrostatic shield 350 is a curved surface. In the present embodiment, each of the outer peripheral end portion and the inner peripheral end portion of the electrostatic shield 350 is formed by a curved surface in which two circular arc portions having different curvature radii in a cross section are continuous. Specifically, each of the outer peripheral end portion and the inner peripheral end portion of the insulator portion 351 is formed by a curved surface in which a circular arc portion having a radius of curvature r1 and an arc portion having a radius of curvature r2 are continuous in a cross section. Each of the conductor portion 352 and the second insulating coating portion 353 has an outer shape substantially similar to the outer shape of the insulator portion 351.

  The curvature radius r2 is larger than the curvature radius r1. In the electrostatic shield 350, the arc portion having the curvature radius r 1 is provided on the winding side adjacent to the electrostatic shield 350, and the arc portion having the curvature radius r 2 is opposite to the winding side adjacent to the electrostatic shield 350. Is provided.

  In the radial direction orthogonal to the direction along the central axis, the width W2 of the electrostatic shield 350 is equal to the width W1 of the winding 320 adjacent to the electrostatic shield 350. In addition, the width W1 of the winding 320 is located on the outermost periphery from the end portion on the inner peripheral side of the first insulating coating portion 342 of the rectangular electric wire 340 located on the innermost periphery toward the radially outer side of the central axis. It is a width | variety to the edge part of the outer peripheral side of the 1st insulation coating part 342 of the flat electric wire 340 to do. In addition, the width W2 of the electrostatic shield 350 is such that the electrostatic shield 350 extends from the outer surface of the second insulating coating portion 353 located at the inner peripheral end of the electrostatic shield 350 toward the radially outer side of the central axis. This is the width between the outer surface of the second insulating coating portion 353 located at the outer peripheral end of 350.

  Equivalent to the width W1 of the winding 320 is a range of 90% to 110% of the width W1 of the winding 320. Since the width W1 of the winding 320 and the width W2 of the electrostatic shield 350 are equal, the end of the winding 320 on the electrostatic shield 350 side and the end of the electrostatic shield 350 on the winding 320 side Electric field concentration in each can be suppressed, and the insulation performance of the stationary induction device 300 can be enhanced.

  The second insulation coating portion 353 includes an inner portion 353a that faces the adjacent winding 320 in the direction along the central axis, and an outer portion 353b that is located on the opposite side of the adjacent winding 320 in the direction along the central axis. Including. The inner part 353a is thicker than the outer part 353b. In the second insulation coating portion 353, the portion constituting the outer peripheral end portion and the inner peripheral end portion of the electrostatic shield 350 located between the outer portion 353b and the inner portion 353a is the thickness of the inner portion 353a. And a thickness greater than or equal to the thickness of the outer portion 353b.

  In the present embodiment, static induction device 300 includes wiring 360 that electrically connects conductor portion 352 of electrostatic shield 350 and electric wire portion 341 at the end of winding 320 adjacent to electrostatic shield 350. Is further provided. As shown in FIG. 14, the wiring 360 is connected to a portion located between the innermost periphery and the outermost periphery in the electric wire portion 341 at the end of the winding 320 adjacent to the electrostatic shield 350. The wiring 360 includes a core wire 361 and a third insulating coating portion 362 that covers the core wire 361.

  Specifically, the conductor portion 352 of the electrostatic shield 350 adjacent to the winding 320 is located between the innermost circumference and the outermost circumference in the flat electric wire 340 located at the end of the winding 320 by the wiring 360. It is connected to the electric wire part 341. As a result, the conductor portion 352 of the electrostatic shield 350 and the electric wire portion 341 located between the innermost circumference and the outermost circumference in the flat electric wire 340 located at the end of the winding 320 are at the same potential. .

  In the flat electric wire 340 located at the end of the winding 320, the electric potential of the electric wire portion 341 located between the innermost circumference and the outermost circumference is lower than the highest electric potential in the plurality of windings provided in the stationary induction device 300. Become. In the static induction device 300 according to the present embodiment, the conductor portion 352 of the electrostatic shield 350 is positioned between the innermost circumference and the outermost circumference in the wire portion 341 at the end of the winding adjacent to the electrostatic shield 350. It is connected to the part. As a result, the conductor portion 352 of the electrostatic shield 350 has the same potential as the electric wire portion 341 located between the innermost circumference and the outermost circumference in the flat electric wire 340 located at the end of the winding 320, and is stationary. The potential is lower than the highest potential in the winding 320 provided in the induction device 300. Therefore, the potential of each of the two electrostatic shields 350 is lower than the highest potential in the adjacent winding 320.

  As a result, in the static induction device 300 according to the present embodiment, the ground potential of the electrostatic shield 350 can be lowered as compared with the case where the conductor portion 352 of the electrostatic shield 350 is connected to the input end. Thereby, the electric field in the outer peripheral side edge part and inner peripheral side edge part of the electrostatic shield 350 can be reduced. In the static induction device 300 according to the present embodiment, there is no need to increase the thickness of the electrostatic shield 350. That is, in the static induction device 300, it is possible to suppress the electric field concentration at the outer peripheral end and the inner peripheral end of the electrostatic shield 350 while suppressing the electrostatic shield 350 from becoming thick.

  As shown in FIG. 14, in the present embodiment, the wiring 360 is connected to the outer peripheral portion of the outer surface of the conductor portion 352, but the present invention is not limited thereto, and the wiring is connected to the inner peripheral portion of the outer surface of the conductor portion 352. 360 may be connected. In order to further ensure the insulation performance between the wiring 360 and the winding 320, the conductor portion 352 is between the adjacent winding 320 in the inner peripheral portion and the outer peripheral portion on the outer surface of the conductor portion 352. It is preferable that the wiring 360 be connected to the one having a smaller potential difference. For the same reason, it is preferable that the wiring 360 is disposed along the surface of the second insulating coating portion 353 of the electrostatic shield 350.

  When connecting the wiring 360 to the electrostatic shield 350, a part of the second insulation coating portion 353 of the electrostatic shield 350 is removed to expose the conductor portion 352, and the core wire 361 is soldered to the exposed portion of the conductor portion 352. Connect by brazing or silver brazing. This connection portion is covered with insulating paper. When connecting the wiring 360 to the winding 320, a part of the first insulation coating portion 342 of the flat wire 340 is removed to expose the wire portion 341, and the core wire 361 is soldered to the exposed portion of the wire portion 341. Connect by silver brazing. This connection portion is covered with insulating paper.

  The electrical connection form of the electrostatic shield 350 is not limited to the above, and is the same as the electrical connection form of the first modified example or the second modified example described in the first embodiment. Also good.

  In the description of the above embodiment, the inner iron type transformer, the outer iron type transformer, and the inner iron type reactor have been described as the stationary induction device. However, the stationary induction device is a stationary induction device other than these. It may be.

  In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It does not become the basis of limited interpretation. Therefore, the technical scope of the present invention is not construed only by the above-described embodiments. In addition, meanings equivalent to the claims and all modifications within the scope are included.

  100, 200, 300 Static induction equipment, 110, 210, 310 Iron core, 120, 220 Low voltage winding, 130, 230 High voltage winding, 140, 240, 340 Flat wire, 141, 241, 341 Wire part, 142, 242, 342 1st insulation coating part, 150, 250, 350 Electrostatic shield, 151, 251, 351 Insulator part, 152, 252, 352 Conductor part, 153, 253, 353 Second insulation coating part, 153a, 253a, 353a Inside Part, 153b, 253b, 353b outer part, 160, 260, 360 wiring, 161, 261, 361 core wire, 162, 262, 362 Third insulation covering part, 270 tank, 320 windings.

Claims (14)

Iron core,
At least one winding wound around the iron core as a central axis;
An annular at least one electrostatic shield disposed adjacent to and corresponding to at least one of the ends of the at least one winding in the direction along the central axis;
The at least one winding includes an electric wire portion and a first insulating covering portion that covers the electric wire portion,
The at least one electrostatic shield includes a conductor portion and a second insulation coating portion covering the conductor portion,
The static induction device wherein the potential of the at least one electrostatic shield is lower than the highest potential in the at least one winding.   2. The static induction device according to claim 1, wherein a width of the at least one electrostatic shield is equal to a width of an adjacent winding in a radial direction perpendicular to the direction along the central axis.   The electric potential of the conductor portion of the at least one electrostatic shield is electrically connected to a portion located between the innermost circumference and the outermost circumference in the electric wire portion at the end of the adjacent winding. The stationary induction device according to claim 2, which is at a potential.   The conductor portion is connected to the wiring at a smaller potential difference between the inner and outer peripheral portions on the outer surface of the conductor portion and the adjacent windings, and the conductor portion is adjacent through the wiring. The stationary induction device according to claim 3, wherein the stationary induction device is electrically connected to the electric wire portion at the end of the winding.   5. The stationary induction device according to claim 4, wherein the wiring is disposed along a surface of the second insulating coating portion of the electrostatic shield.   3. The stationary state according to claim 2, wherein the electric potential of the conductor portion of the at least one electrostatic shield is electrically connected to the electric wire portion other than the end portion of the adjacent winding and has the same electric potential. Induction equipment.   The stationary induction device according to claim 2, wherein the conductor portion of the at least one electrostatic shield is electrically floating. The second insulating covering portion includes an inner portion that faces an adjacent winding in the direction along the central axis, and an outer portion that is located on the opposite side of the adjacent winding in the direction along the central axis.
The stationary induction device according to claim 2, wherein the inner part is thicker than the outer part. The at least one winding includes a plurality of windings,
The stationary induction device according to claim 2, wherein the plurality of windings are wound concentrically around the iron core. The at least one winding includes a plurality of windings,
The stationary induction device according to claim 2, wherein the plurality of windings are wound around the iron core and arranged coaxially. The at least one winding includes a plurality of windings,
A plurality of electrostatic shields as the at least one electrostatic shield;
The plurality of electrostatic shields are arranged adjacent to each other in a one-to-one correspondence with at least one of the end portions of the plurality of windings,
2. The stationary induction device according to claim 1, wherein a potential of each of the plurality of electrostatic shields is lower than a highest potential in the plurality of windings.   Among the plurality of electrostatic shields, the potential of the conductor portion of the electrostatic shield adjacent to the end of the winding having the highest potential in the plurality of windings is the same at the end of the adjacent winding. The stationary induction device according to claim 11, which is electrically connected to a portion located between the innermost periphery and the outermost periphery in the electric wire portion and has the same potential.   Among the plurality of electrostatic shields, the potential of the conductor portion of the electrostatic shield adjacent to the end of the winding having the highest potential in the plurality of windings is other than the end of the adjacent winding. The stationary induction device according to claim 11, which is electrically connected to the electric wire portion and has the same potential.   The static induction device according to claim 11, wherein the potential of each of the plurality of electrostatic shields is a potential that is one-to-one and lower than the highest potential in adjacent windings.

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