JP7308726B2 - stationary induction motor - Google Patents

Description

The present invention relates to static induction electric machines such as transformers and reactors.

In a stationary induction electric machine, such as a transformer, the main factors that generate heat are copper loss due to heat in windings that make up the transformer, iron loss such as hysteresis loss and eddy current loss in the iron core. If the heat is not dissipated properly, the temperature inside the transformer will continue to rise, damaging the main body of the transformer and significantly shortening the life of the transformer.

For this reason, transformers are generally constructed by placing the main body of the transformer, which consists of the windings and iron core, inside a tank, filling the tank with a cooling medium such as insulating oil, and cooling the heat generated by the main body of the transformer with the cooling medium. are doing. In natural cooling by cooling medium, natural convection generated by utilizing the temperature gradient inside the transformer is used for cooling. In the convective circulation of the cooling medium, the temperature of the cooling medium around the windings rises, and the hot cooling medium moves to the upper part of the tank and dissipates heat into the air through the tank. As the cold coolant moves to the bottom of the tank and the warm coolant moves to the top of the tank, heat circulation occurs inside the tank and the whole is gradually cooled. Improving the cooling performance is extremely important in reducing the size and weight of the static induction motor, and various static induction motors have been developed with improved cooling performance.

For example, in Japanese Utility Model Laid-Open No. 5-87920 (Patent Document 1), a lead bar made of a pure metal conductor is formed into a tubular shape in order to effectively cool the heat of the main body of the transformer with the cooling medium in the tank. , a technique is disclosed in which a heat pipe structure is provided inside the tubular shape. With this structure, the heat inside the main body of the transformer (the heat inside the windings) can be transported to a position where it can be cooled by the cooling medium in the tank, and the cooling performance can be improved.

Japanese Utility Model Laid-Open No. 5-87920

The technique of Patent Literature 1 transports the heat generated by the windings through the lead bar of the heat pipe structure and effectively performs cooling by the cooling medium, so that the cooling performance can be improved.

However, in the technique disclosed in Patent Document 1, the heat transport by the lead bar remains within the tank. Therefore, the heat is transferred to the cooling medium in the tank, and the heat from the cooling medium is indirectly radiated to the atmosphere (outside air) through the outer wall of the tank. Generally, the temperature of the cooling medium in the tank of the transformer is above 80°C, while the temperature of the outside air is much lower. Therefore, if the heat generated in the main body of the transformer can be not only cooled by the cooling medium in the tank but also efficiently transported (transferred) to the outside, the cooling performance will be greatly improved. Patent Literature 1 does not describe directly transferring the heat generated in the main body of the transformer to the external space (into the atmosphere), leaving a technical problem in terms of improving the cooling performance.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a static induction electric machine that has a simple structure and can improve cooling performance.

As an example, the present invention comprises a static induction machine body having an iron core and windings, a tank containing the static induction machine body and having a cooling medium, and an overhead wire outside the windings and the tank. a connection wire for connection, the connection wire being connected to the winding, the winding side connection wire having a heat pipe inside, and the upper end being outside the tank. The stationary induction electric machine includes an exposed connection terminal having a heat pipe inside, and a conductor connecting between the winding-side connection wire and the connection terminal.

INDUSTRIAL APPLICABILITY The present invention can realize a stationary induction electric machine with improved cooling performance while having a simple configuration.

1 is a diagram showing the configuration of a transformer in Example 1 of the present invention; FIG. FIG. 2 is a diagram showing the configuration of main parts in Example 1; It is a figure which shows the structure of the transformer in Example 2 of this invention. It is a figure which shows the principal part structure of the transformer in Example 3 of this invention.

EMBODIMENT OF THE INVENTION Hereinafter, the form (Example) for implementing this invention is demonstrated using drawing. In the following description, the same reference numerals (numbers) are given to the same devices and the same operation processes, and the devices and operations that have already been described may be omitted in the description of the drawings that will be described later. In addition, the present invention is not limited to the following examples.

<<Embodiment 1 of the present invention>>
Next, Example 1 of the present invention will be described. FIG. 1 is a diagram showing the structure of a transformer in Example 1 of the present invention. FIG. 2 is a diagram showing a main part (connection line) of the first embodiment shown in FIG.

(Configuration of Embodiment 1)
1 and 2, the main body of the transformer is composed of an iron core 1 and a winding 2 (coil) wound around the iron core 1. As shown in FIG. The main body of the transformer is housed in the tank 3 and fixed. The inside of the tank 3 is filled with an insulating cooling medium (cooling insulating oil, cooling gas, etc.), and the main body of the transformer is cooled by this cooling medium. Here, in the tank 3 in FIG. 1, only the upper cover portion for arranging the equipment connected to the main body of the transformer is shown, and the overall structure is omitted. Illustration of the cooling medium is also omitted. On the outside of the tank 3 (upper surface of the upper lid), a primary side terminal 4 for connecting to the primary side of the winding 2 of the transformer, a secondary side terminal 5, and electrical insulation between the primary side and the secondary side are provided. An insulator 6 is arranged for carrying out. The secondary side terminal 5 is disposed such that an upper portion protrudes outside the tank 3 and a lower portion is positioned inside the tank 3 . Although the first embodiment shows an example of a three-phase transformer, it goes without saying that the present invention can be similarly implemented with a single-phase transformer.

Further, the secondary end of the winding 2 and the secondary terminal 5 are connected by a connection wire which is a good conductor. Copper, aluminum, or the like, which has good thermal conductivity and low electrical resistance, is used as the connection wire. The "connection line" in this first embodiment includes a winding-side connection line 7 having a lower end connected to the winding 2, an outer peripheral surface immersed in a cooling medium (not shown), and a heat pipe 7a inside. , and a connection terminal 5 (secondary side terminal in this example) having an upper end exposed to the outside of the tank and having a heat pipe 5a therein. The “connection line” further has a flexible conductor 8 that connects between the winding-side connection line 7 and the secondary-side terminal 5 . The flexible conductor 8 is a bendable conductor. The winding-side connecting wire 7 and the secondary-side terminal 5 each have a hollow inside, and a heat pipe in which a working fluid (for example, water) is enclosed in the hollow and the inside of the hollow has a wick structure. It has a structure with That is, the winding-side connection line 7 and the secondary-side terminal 5 each have a heat pipe. As the working fluid for the heat pipe, other than water, for example, known working fluids such as freon, methanol, and ammonia can be used.

(Cooling action in Example 1)
The heat generated in the main body of the transformer (mainly the winding 2) is basically cooled by the cooling medium (for example, cooling oil) filled in the tank 3, but in this first embodiment, further, The heat generated in the main body of the transformer is transported to the portion of the secondary side terminal 5 located outside the tank 3, and is radiated to the outside air for cooling. That is, the heat generated in the winding 2 is transported to the upper end by the heat pipe 7a of the winding-side connecting wire 7, and further, the transported heat is transmitted to the secondary-side terminal 5 via the flexible lead wire 8. be done. In the secondary side terminal 5, the heat is further transported to the upper portion of the secondary side terminal 5 (the portion outside the tank) by the internal heat pipe 5a, and the heat is released to the outside air from the portion of the secondary side terminal protruding outside the tank. be. In this way, the heat generated inside the transformer is directly transported to the outside of the tank and released to the outside air, thereby greatly improving the cooling performance.

In this embodiment, the winding-side connecting wire 7 and the secondary-side terminal 5 are connected by a flexible lead wire 8, and the connecting wire having a heat pipe structure has restrictions on the arrangement of transformer devices (transformer equipment). It is necessary to adjust the arrangement so as to eliminate the positional deviation between the arrangement position of the external secondary side terminal 5 and the position of the end of the winding 2 in the tank 3). That is, even if there is a deviation between the end position of the winding 2 and the position of the secondary terminal 5, the flexible conductor 8 can be bent freely, so there is no need to consider this positional deviation due to bending deformation of the flexible conductor. Gone.

In the first embodiment, the structure of the "connection line" on the secondary side is a structure in which the secondary side winding side connection line 7 having a heat pipe and the secondary side terminal 5 are connected by a flexible lead wire. , but the "connection line" on the primary side may have the same configuration as that on the secondary side. Alternatively, similar "connection lines" can be used for both the primary and secondary sides.

(Effect of Example 1)
As described above, according to the first embodiment of the present invention, the heat generated in the main body of the transformer is cooled by the cooling medium, and is actively transported to the outside using the heat pipe and the flexible lead wire. Since it has a structure that dissipates heat, the cooling performance is dramatically improved. Furthermore, since the coil-side connection line and the external terminal are connected by a flexible lead wire, the problem of misalignment between the end of the coil and the external terminal can be resolved. In addition, since this cooling structure can be achieved only by devising the structure of the connection line, there is no need to provide a special structure for cooling separately from the "connection line". Therefore, high cooling performance can be achieved with a simple configuration.

<<Embodiment 2 of the present invention>>
Next, Example 2 of the present invention will be described. FIG. 3 is a diagram showing the configuration of a transformer in Example 2 of the present invention. Note that the description of the core 1 and the winding 2 of the transformer is omitted in FIG. Further, descriptions of the core 1, the windings 2, the tank 3, etc. are also omitted.

In FIG. 3, the basic configuration is the same as in FIG. The main difference is that the secondary terminals are arranged to be shifted from each other. In this second embodiment, as shown in FIG. 3, the secondary terminals 5 are arranged so as to be shifted from each other, and the secondary terminals 5 are arranged obliquely (at a predetermined angle with respect to the direction indicated by the dashed line). are arranged obliquely so as to have Note that the two broken lines in FIG. 3 are provided to make it easier to understand that the secondary terminals are arranged to be shifted from each other, and have no other meaning. In the second embodiment, an air rectifying plate 9 is further disposed apart from the insulator 6, and the secondary terminal 5 is arranged between the insulator 6 and the air rectifying plate 9. This makes it easier for the airflow to hit the surface of the portion of the secondary side terminal 5 that protrudes into the outside air.
With such a configuration, the air flow that hits the secondary side terminal 5 is increased, so that the heat transported to the contact portion (upper end portion) with the outside air can be efficiently radiated by the air flow.

(Effect of Example 2)
According to the second embodiment of the present invention, it can be expected to have the same effect as the above-described first embodiment, and to further improve the cooling performance.

<<Embodiment 3 of the present invention>>
Next, Example 3 of the present invention will be described. FIG. 4 is a diagram showing a main part of a transformer in Example 3 of the present invention. In FIG. 4, description of the core 1, the winding 2, the tank 3, etc. of the transformer is omitted. Further, descriptions of the core 1, the windings 2, the tank 3, etc. are also omitted.

In FIG. 4, a heat radiation fin 10 is provided at the upper end portion of the secondary side terminal 5, which is in contact with the outside air. With this configuration, the heat generated in the main body of the transformer is directly transported by the "connection line" and radiated to the atmosphere by the fins 10, thereby improving the cooling performance. Moreover, in the structure of FIG. 4, if a fan (not shown) is provided so as to apply an air flow to the fins 10, the cooling performance of the fins 10 can be further improved.

(Effect of Example 3)
According to the third embodiment of the present invention, it can be expected to have the same effect as the above-described first embodiment, and to further improve the cooling performance.

<<Other embodiments of the present invention>>
The present invention is not limited to the one embodiment of the present invention described above, and includes various modifications within the scope of the technical idea of the present invention. For example, the present invention can be implemented not only with transformers but also with other static induction devices (eg, reactors). Further, the first to third embodiments described above are detailed descriptions for easy understanding of the present invention, and are not necessarily limited to those having all the described configurations.

DESCRIPTION OF SYMBOLS 1... Iron core 2... Winding 3... Tank 4... Primary side terminal 5... Secondary side terminal 5a... Heat pipe 6... Insulator 7... Winding side connection wire 7a... Heat pipe 8 ... flexible conductor, 9 ... plate for air rectification, 10 ... fin

Claims (5)

A stationary induction device body having an iron core and windings, a tank containing the stationary induction device body and having a cooling medium, and a connection wire for connecting the windings and an overhead wire outside the tank. A stationary induction machine,
The connection line is connected to the winding, and includes a winding-side connection line having a heat pipe inside, a connection terminal having an upper end exposed outside the tank and having a heat pipe inside, and the winding. A conductor connects between the side connection line and the connection terminal,
A stationary induction machine , wherein said conductor is a flexible conductor . 2. A static induction electric machine according to claim 1, wherein an insulator is arranged between the primary side and the secondary side of said connection terminal outside said tank. 2. A static induction electric machine according to claim 1, wherein said connection terminals are arranged in a staggered manner. 2. The static induction electric machine according to claim 1, wherein fins are provided at portions of said connection terminals that come into contact with the outside air. 5. A static induction electric machine according to claim 4 , further comprising a fan for supplying air flow to said fins.

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