Static induction circuit

Abstract

To provide a stationary induction appliance capable of enhancing the reliability of a wound iron core by adjusting the interlayer resistance in the wound iron core to an appropriate resistance.SOLUTION: The stationary induction appliance has a wound iron core and a winding wound around the wound iron core. The wound iron core has an amorphous foil strip, a silicon steel plate, and an interlayer resistance adjustment part that adjusts the interlayer resistance of the wound iron core.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a static induction device. [Background technology]

[0002] Patent Document 1 describes a technology for a transformer that has an amorphous magnetic ribbon core and a silicon steel sheet as a wound core and that can achieve a high core occupancy rate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-174113 Summary of the Invention [Problem to be solved by the invention]

[0004] As amorphous core transformers become larger and higher voltage, it is necessary to suppress eddy current loss in the amorphous core.

[0005] If the slight oxide film on the surface of the amorphous foil strip is damaged during manufacturing, it will result in multi-point grounding, increasing eddy current loss. Eddy current loss occurs within the amorphous core as shown in equation (1) below. Note that equation (1) is the theoretical formula for eddy current loss in an iron core.

[0006] Wie∝ t 2 f 2 Bm 2 / rs formula (1) where Wie is eddy current loss, t is iron core thickness, f is frequency, Bm is maximum magnetic flux density of the iron core, and rs is interlayer resistance.

[0007] Patent Document 1 does not disclose how to appropriately adjust the interlayer resistance in the amorphous core, and therefore does not give sufficient consideration to suppressing eddy current loss. Furthermore, if the interlayer resistance in the amorphous core increases, eddy current loss can be suppressed, but the voltage applied to the wound core increases, increasing the possibility of dielectric breakdown of the oxide film on the silicon steel sheet. With conventional technology, it is difficult to ensure the reliability of the core.

[0008] An object of the present invention is to adjust the interlaminar resistance in a wound core to an appropriate resistance and thereby improve the reliability of the wound core. [Means for solving the problem]

[0009] The present invention provides a static induction motor having a wound core and a winding wound around the wound core, The wound core is a static induction device having an amorphous foil band, a silicon steel plate, and an interlayer resistance adjusting section that adjusts the interlayer resistance of the wound core. [Effects of the Invention]

[0010] According to the present invention, the interlaminar resistance in the wound core can be adjusted to an appropriate resistance, thereby improving the reliability of the wound core. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating a transformer according to a first embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged view of a part of FIG. [Figure 3] FIG. 10 is a diagram illustrating a wound core according to a third embodiment. [Figure 4] FIG. 1 is a diagram of a transformer as a comparative example of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] The static induction motor of the present invention will be described below based on the illustrated embodiments. In each embodiment, the same components are designated by the same reference numerals.

[0013] A transformer as a comparative example is shown in Fig. 4. This is an amorphous core transformer consisting of a winding 1, an amorphous foil band core 2, and a grounding part 3.

[0014] In the transformer core structure shown in Figure 4, if a scratch occurs in the core (wound core) during the manufacturing process, the oxide film of the amorphous material will be locally scraped off, reducing the interlaminar resistance in the thickness direction of the wound core and increasing the risk of increased eddy current loss. Furthermore, since voltage is shared between the winding and the core when voltage is applied during actual operation or during a lightning strike, if the interlaminar resistance in the thickness direction of the wound core increases, the voltage applied to the wound core will increase, increasing the possibility of dielectric breakdown when the oxide film on the silicon steel plate is scraped off. Therefore, it is desirable to adjust the interlaminar resistance in the thickness direction of the wound core to an appropriate value. [Example]

[0015] Fig. 1 shows a transformer as a stationary induction machine in Example 1. Fig. 2 is a diagram illustrating the laminated structure of a wound core in Example 1.

[0016] As shown in Figure 1, the transformer of this embodiment is an example of a five-legged core, with four wound cores arranged horizontally. Each wound core has silicon steel 5 arranged on the outer periphery, and a winding 1 is wound around it as a coil. Each wound core is connected to a grounding part 3, such as a tank. Protective material 6 (insulating material such as pressboard, kraft paper, or synthetic resin) is inserted between each wound core. Placing protective material 6 between each wound core prevents multi-point grounding.

[0017] Figure 2 is an enlarged view of the structure of a portion 10 of the wound core surrounded by a dotted line in Figure 1. As shown in Figure 2, the wound core in this embodiment is configured by laminating and winding an inner circumferential silicon steel layer 5, an amorphous material foil strip 2, and an outer circumferential silicon steel layer 5. The thickness of the silicon steel layer is 0.23 mm to 0.35 mm, and the thickness of the amorphous material foil strip is 25 μm.

[0018] A first copper plate (conductive plate) 4 serving as a shield plate is sandwiched between the silicon steel plates 5 on the inner periphery side. A second copper plate (conductive plate) 4 serving as a shield plate is sandwiched between the silicon steel plates 5 on the outer periphery side.

[0019] A copper wire 22 serving as a shield jumper is connected to the first copper plate 4 and the second copper plate 4, and the second copper plate 4 is connected to the grounding part 3 via an electric wire such as a copper wire. The first copper plate 4, the second copper plate 4, and the copper wire 22 form an interlayer resistance adjusting part that adjusts the interlayer resistance in the thickness direction of the wound iron core of the transformer. By changing the thickness, length, and cross-sectional area of ​​the first copper plate 4 and the second copper plate 4, or by changing the resistance value of the copper wire 22, the interlayer resistance adjusting part can adjust the interlayer resistance to an appropriate resistance value.

[0020] 2 shows a configuration in which the first copper plate 4 and the second copper plate 4 are sandwiched between silicon steel plates, but the first copper plate 4 or the second copper plate 4 may also be sandwiched between the wound core 2 of an amorphous material foil band. The first copper plate 4 and the second copper plate 4 can be arranged at the lap joint of the wound core, making it easier to arrange them, and the wound core of this embodiment can be manufactured at low cost.

[0021] The silicon steel plates 5 may be disposed only on either the outer circumferential side or the inner circumferential side of the amorphous material foil strip 2. Alternatively, by disposing the silicon steel plates 5 on both the outer circumferential side and the inner circumferential side, the rigidity of the wound core can be increased, thereby improving reliability.

[0022] According to this embodiment, the interlayer resistance of the wound core can be appropriately adjusted, thereby suppressing eddy current loss. Furthermore, by setting the interlayer resistance in the thickness direction of the wound core to an appropriate value, it is possible to prevent dielectric breakdown between the layers of the wound core when voltage is applied during actual operation or during a lightning strike, thereby improving reliability. [Example]

[0023] In the first embodiment, as shown in FIG. 2, four wound cores each formed by laminating and winding a silicon steel plate 5, an amorphous foil strip 2, and a copper plate 4 are arranged horizontally.

[0024] The present invention is not limited to a wound core having such a configuration, and Example 2 can also be applied to a transformer having a configuration in which a wound core arranged on the inside and a wound core arranged on the outside of the wound core arranged on the inside are combined.

[0025] In the second embodiment, the configuration of the inner wound core and the configuration of the outer wound core can be the same as that shown in FIG. 2 in the first embodiment.

[0026] According to this embodiment, similar to the first embodiment, reliability can be improved even in a transformer having a configuration in which a wound core arranged on the inside and a wound core arranged on the outside are combined. [Example]

[0027] Fig. 3 is a diagram showing the configuration of a wound core of a transformer in Example 3. Differences from Fig. 2 showing the wound core in Example 1 will be described below.

[0028] In this embodiment, a semiconductive material is applied to the first copper plate 4 on the inner periphery and the second copper plate 4 on the outer periphery. By covering the first copper plate 4 and the second copper plate 4 with the semiconductive material 7, the interlaminar resistance in the wound core can be more easily adjusted than in the first embodiment.

[0029] Here, as the semiconductive material, a semiconductive material containing epoxy resin and carbon (available in FVR-L, FVR-M, and FVR-H models, manufactured by Nippon Mica) can be used.

[0030] In this embodiment as well, the interlaminar resistance of the wound core can be adjusted, so that eddy current loss can be suppressed and insulation breakdown of the wound core can be prevented, thereby improving reliability. [Explanation of symbols]

[0031] 1 Winding, 2 Amorphous foil band core, 3 Grounding part, 4 Copper plate, 5 Silicon steel core, 6 Protective material, 7 Semiconductive material

Claims

1. A static induction machine having a wound core and a winding wound around the wound core, The wound core is an amorphous foil strip, a silicon steel plate, and an interlayer resistance adjusting section that adjusts the interlayer resistance of the wound core; The interlayer resistance adjusting portion is a static inductor disposed at the lap joint.

2. A static induction machine having a wound core and a winding wound around the wound core, The wound core is an amorphous foil strip, a silicon steel plate, and an interlayer resistance adjusting section that adjusts the interlayer resistance of the wound core; the interlayer resistance adjusting portion has a conductive plate, The conductive plate is covered with a semiconductive material.

3. The static induction device according to claim 1 or 2, The interlayer resistance adjusting section has a first conductive plate, a second conductive plate, and a conductor connecting the conductive plates, and the second conductive plate is a static induction device that is grounded.

4. The static induction device according to claim 1 or 2, A static induction machine in which a plurality of the wound cores are arranged, and a protective material as an insulator is arranged between each wound core.

5. The static induction device according to claim 1 or 2, The wound core is a stationary induction motor having an inner wound core and an outer wound core.

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