JPH08191020A - Transformer - Google Patents

Abstract

PURPOSE: To cool a transformer coil by transferring the heat from a high-temp. part of the coil to a low-temp. part thereof in its temp. distribution, using heat pipes in the inside of the transformer. CONSTITUTION: A coil 1 is disposed in a transformer tank and space around the coil is filled with an insulation oil 17. The coil has a straight outer and inner peripheral parts 1a and 1b and square-C-shaped insulators 3a and 3b between which the ends 4a and 5a (evaporation) of heat pipes 4 and 5 are inserted; the other ends (condenser) 4b, 5b thereof are bent and disposed along a circular arc-shaped outer peripheral part 1c of the coil 1 with specified space. The heat produced at the parts 1a and 1b of the coil 1 are collected at the ends 4a and 5a of the heat pipes 4 and 5, transported to the ends 4b and 5b and radiated into the oil 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer for cooling a coil using a heat pipe.

[0002]

2. Description of the Related Art In recent years, heat pipes have been studied for application to cooling transformer coils. The method is to place the evaporating part, which is one end of the heat pipe, in the high temperature part of the coil, and the condensing part, which is the other end, in the cooling device outside the transformer so that the heat generated in the high temperature part of the coil It is generally conceivable that the heat transfer is received by the evaporation section of the heat pipe and is transported to the condensation section by the working fluid inside, and the heat is radiated by the external cooling device.

Since the heat transfer amount of the heat pipe is several times that of the electric conductor and the transport speed is also close to the sonic velocity, when applied to cooling a vehicle transformer or the like in which the load changes drastically, It is expected that the heat can be effectively dissipated by following the sudden change in temperature due to the increase or decrease.

[0004]

However, when this heat pipe is actually applied to the cooling of the coil inside the transformer, there are the following problems. First, the diameter of the heat pipe is usually several mm to several tens of mm. And
Since heat moves from the periphery of the evaporating portion of the heat pipe to the working fluid inside, the heat flow density of the evaporating portion (heat collecting portion) arranged at the high temperature portion of the coil becomes extremely large. Further, in order to pull out the condensing part of the heat pipe to the outside of the transformer for cooling, it is necessary to electrically insulate the heat pipe and the coil, and it is necessary to insert an insulator at the contact part between them. is there.

Therefore, in practice, in the evaporation portion of the heat pipe, heat must be transferred through the insulator, which is generally a material having poor thermal conductivity. The temperature gradient in that portion is represented by the following equation, which is a general equation for heat conduction. θ1-θ2 = Q · L / (λ · S) where Q is the amount of heat transferred, λ is the thermal conductivity, L is the length (thickness) of the insulator, θ1-θ2 is the temperature difference, and S is the heat transport area. Indicates. That is, the temperature difference is Q / S indicating the heat flow density and the length L.
Becomes larger, and the thermal conductivity λ becomes smaller, the larger.

Since the heat pipe has a large heat transport capacity, its heat flow density is large. Since the insulator is inserted between the heat pipe and the coil, the length L becomes long, and the thermal conductivity of the insulator is large. Is small, the thermal conductivity λ is small. Therefore, the temperature difference between the coil and the heat pipe becomes large, and the actual heat transfer efficiency is 20 to 30%.
There may be a degree.

The following are possible methods for solving this problem. A plate material having good thermal conductivity is attached to the evaporation portion of the heat pipe to increase the contact area with the coil. An insulator having a large thermal conductivity is used as an insulator inserted between the two. The heat flow density of each evaporator is reduced by using a plurality of heat pipes.

However, the method (1) is effective when the heat source is small, but in the case of a large heat source such as a coil of a transformer, it is necessary to make the size of the plate material to be attached to the same level as the coil. The thickness of the plate material also has to be considerably increased in order to reduce the temperature gradient of the plate material itself, and cannot be configured in a small size.

In the method (1), since a material having a good thermal conductivity generally has a good electric conductivity, no suitable material having the required contradictory properties exists at present. The only alumina nitride ceramics have relatively good characteristics, but they are not practical because they are not flexible.

In the above method, the heat flow density per location is reduced by using a plurality of heat pipes, which is effective for a large heat source such as a coil of a transformer. However, taps and leads are complicatedly arranged near the coil of the transformer, and the iron core is closely arranged around the coil, so even if multiple heat pipes are actually attached. ,
In order to guide them to the external cooling device, it is necessary to enlarge the iron core or to increase the coil interval, which eventually leads to the size increase of the transformer.

As described above, there are currently no good solutions to various problems in the case of actually using a heat pipe for cooling the coils of a transformer, and the purpose is to make it compact by taking advantage of its high heat transport capacity. Not achieved. The present invention solves the above problems, and an object thereof is to provide a transformer capable of effectively cooling a coil by using a heat pipe.

[0012]

In order to achieve the above object, a transformer according to a first aspect of the present invention is a transformer in which a coil conductor is wound in a plate shape, and a coil is in contact with a peripheral portion of the coil or between the coil conductors. A heat pipe provided at a position and a cooling medium flowing along the plate-shaped surface of the coil are provided, and the heat pipe is provided so as to extend along the winding direction of the coil conductor, and the evaporation portion thereof is the coil. It is characterized in that it is located in a portion where the temperature becomes relatively high, and the condensing portion is located in the cooling medium or in a portion where the temperature becomes low in the coil.

In this case, the heat pipe may be configured such that both ends thereof are located in the cooling medium or in the portion of the coil having the low temperature while passing through the portion of the coil having the high temperature (claim 2). Further, the heat pipe may be configured such that both ends thereof are electrically connected to the coil conductor (claim 3).

According to a fourth aspect of the transformer, a coil formed by winding a coil conductor in a plate shape, a heat pipe provided in contact with a peripheral portion of the coil, and cooling flowing along a plate surface of the coil. The heat pipe is provided so as to extend along the winding direction of the coil conductor, and the evaporation portion thereof is located at a portion of the coil where the temperature is relatively high, and
The condensing portion is configured to be located in the cooling medium or a portion of the coil where the temperature is low, and the outer circumference of the cross section is formed with a curvature smaller than that of the cross section of the coil conductor.
In addition, a part thereof is electrically connected to the coil conductor.

A transformer according to a fifth aspect of the present invention comprises a coil formed by winding a coil conductor, a part of which is formed of a heat pipe, in a plate shape, and a cooling medium flowing along the plate surface of the coil. The heat pipe of the coil is characterized in that the evaporating portion is located in a portion of the coil where the temperature is relatively high, and the condensing portion is located in the cooling medium or in a portion of the coil where the temperature is low. To do. In addition, the coil conductor may be made of aluminum (claim 6).

[0016]

According to the transformer of the first aspect of the present invention, the heat of the relatively high temperature portion of the coil is transferred to the cooling medium or the low temperature portion of the coil by the heat pipe. The effect of averaging is to cool the hot part of the coil.

According to the transformer of the second aspect, the heat collected in the part of the heat pipe arranged in the high temperature part of the coil is arranged in the cooling medium or in the low temperature part of the coil. Since heat is dissipated at both ends of the heat pipe, more effective heat dissipation can be performed.

According to the transformer of the third aspect, the current of the coil is shunted to the electrically connected heat pipe, so that the heat generation amount of the coil conductor portion is reduced accordingly. According to the transformer of the fourth aspect, the electric field to the earth electrode portion on the outer peripheral portion of the coil is relaxed by the heat pipe, and the generation of corona discharge is suppressed.

According to the transformer of the fifth aspect, since the coil can be made small because a part of the coil is constituted by the heat pipe, a space for arranging the heat pipe is required inside the transformer. do not do. According to the transformer of the sixth aspect, it is possible to reduce the weight of the transformer by forming the coil conductor with aluminum.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to an oil-fed air-cooled vehicle transformer will be described below with reference to FIGS. In FIG. 1A, a coil 1 is formed by alternately laminating a high voltage coil and a low voltage coil, which are coiled conductors each having a rectangular cross section and are wound in an elliptical and flat plate shape. A laminated iron core 2 is disposed inside and outside the portion so as to interlink with the coil 1.
Since the iron core 2 of the ground electrode and the high voltage coil 1 are insulated between the iron core 2 and the linear outer peripheral portion 1a and inner peripheral portion 1b of the coil 1, as shown in FIG. Insulators 3a and 3b having a U-shaped cross section are fitted.

Two substantially rectangular heat pipes 4 are inserted between the outer peripheral portion 1a of the coil 1 and the insulator 3a. These heat pipes 4 are provided so as to be in contact with the outer peripheral portion 1a of the coil 1 and extend along a linear portion that is the winding direction of the coil conductor, and one end of the evaporation portion (heat collecting portion) 4a is The condenser portion (heat dissipation portion) 4b, which is located at the center of the linear portion that is the portion of the outer peripheral portion 1a that has a relatively high temperature, and the other end portion of the condenser portion (heat radiating portion) 4b, have a predetermined arcuate outer peripheral portion 1c. It is curved so that it follows the interval.

Two heat pipes 5 having the same shape as the heat pipe 4 are also inserted between the inner peripheral portion 1b of the coil 1 and the insulator 3b. These heat pipes 5 are provided so as to be in contact with the inner peripheral portion 1b of the coil 1 and extend along a linear portion which is the winding direction of the coil conductor, and the evaporation portion 5a as one end is the inner peripheral portion 1b. The condensing portion 5b, which is located at the center of the linear portion of the coil and is the other end thereof, is bent along the inner peripheral portion 1d of the coil 1. Then, these components are housed in a transformer tank (not shown) in a form fit type and filled with insulating oil 17 which is a cooling medium. The insulating oil 17 is forcibly circulated and cooled by an oil pump and an oil cooler that communicate with the transformer tank via pipes. The coil 1 is cooled by flowing from one end to the other end in the longitudinal direction.

Next, the operation of this embodiment will be described with reference to FIGS. 2 and 3. In the normal operation state of the transformer, the high voltage side coil 1 is energized from the power supply terminal (not shown) through the lead-out portions 6a and 6b, and the current also flows through the low voltage side coil that is electromagnetically coupled. The temperature of 1 rises. At this time, the outer peripheral portion 1a and the inner peripheral portion 1b of the coil 1, which are covered with the insulators 3a and 3b, are relatively hotter than other portions because heat is not sufficiently dissipated. On the other hand, a portion of the linear portion of the coil 1 not covered with the insulators 3a and 3b, and an arc-shaped outer peripheral portion 1c and inner peripheral portion 1d located at both longitudinal end portions of the coil 1 are circulated insulating oil. Since it is sufficiently cooled by 17, and the heat is radiated relatively well, the temperature does not rise so much.

FIG. 2 shows the temperature distribution in the AA cross section of the linear portion of the coil 1 of FIG. In FIG.
When the heat pipe is not used, the temperature distribution is the highest at the outermost periphery of the coil 1 as shown by the curve a, and the insulator 3a
Is inclined in a direction in which it decreases from the contact portion to the non-contact portion.

Here, when the heat pipe 4 is arranged at the outermost peripheral portion, the heat at the outermost peripheral portion of the coil 1 is collected by the evaporating portion 4a of the heat pipe 4 and is relatively lower than the evaporating portion 4a. The temperature of the outer peripheral portion 1a of the coil 1 is lowered because the heat is transferred to the condenser portion 4b located in the portion and is radiated.
When the temperature of the outermost peripheral portion of the coil 1 decreases, the heat of the adjacent conductor wound along the coil 1 also moves to the outermost peripheral portion by heat conduction.

In this case, the more the conductor is farther from the heat pipe 4, the less heat is transferred, but the temperature of the entire outer peripheral portion 1a is lowered by the heat transport by the heat pipe 4. The result is the curve b in FIG. 2, and the temperature of the outer peripheral portion 1a of the coil 1 is obviously lowered, and the temperature of the central portion which is the non-contact portion of the insulator 3a is also the outer peripheral portion 1a.
Is slightly reduced by the transfer of heat to. This effect is the same as in the inner peripheral portion 1b of the coil 1, and the temperature of the inner peripheral portion 1b of the coil 1 is lowered by the provision of the heat pipe 5.

Further, as shown in the second embodiment of FIGS. 4 (a) and 4 (b), in addition to the heat pipe 4, two heat pipes 7 are provided for the coil 1 which is the contact portion of the insulator 3a. It is inserted so as to extend along the winding direction of the coil conductor at a few turns from the outermost peripheral portion of the outer peripheral portion 1a, the condensing portion 7b is arranged at a portion which is not in contact with the insulator 3a, and the evaporating portion 7a is disposed. It can be configured to be arranged in the central portion of the linear portion.
Although the illustration of the inner peripheral portion 1b side of the coil 1 is omitted, the coil 1 has the same configuration. The temperature distribution in this case is the curve c in FIG. 3, which indicates that the temperature of the contact portion of the insulator 3a has further decreased.

As described above, according to this embodiment, the peripheral portions such as the outer peripheral portion 1a and the inner peripheral portion 1b of the coil 1 which are in a relatively high temperature state and the insulators 3a and 3b, and further the coil conductor. During the winding of the heat pipes 4, 5 and 7, the evaporation parts 4a,
By inserting 5a and 7a, the heat generated there is collected and transported by the heat pipes 4, 5 and 7 to the condensing sections 4b, 5b and 7b located at relatively low temperature parts for heat dissipation.

According to this structure, the heat is not collected from the entire coil 1 and transported to the outside of the transformer, but the heat of the relatively high temperature portion of the coil 1 is collected and the low temperature portion inside the transformer is collected. Coil 1 and heat pipe 4,
It does not require a large contact area with 5 and 7, and the heat flow density can be reduced. Also, the heat pipe 4,
Since 5 and 7 are not drawn to the outside of the transformer, if the heat pipes 4, 5 and 7 are insulated to the same extent as the coil conductor, there is no need to interpose an insulator with the coil 1. Therefore, the temperature gradient at the contact portion between the two becomes small, and the heat is effectively transferred by the heat pipes 4, 5, and 7 which could not be realized by the conventional cooling method, so that the coil 1 can be cooled. it can.

FIG. 3 shows the temperature distribution of the coil 1 in this embodiment (solid line) and the temperature distribution of the coil without a heat pipe (conventional example) (two-dot chain line).
Usually, in a transformer, the average temperature of the coil is calculated with reference to the maximum allowable temperature Tm, and the size of the coil conductor is designed based on this average temperature. In the conventional example, the average temperature Ta is as shown by the two-dot chain line from the temperature distribution shown by the two-dot chain line. On the other hand, the temperature distribution of the coil 1 in this embodiment when the cooling is effectively performed by the heat pipes 4 and 5 is indicated by the solid line because the temperature difference between the high temperature portion and the low temperature portion is averaged. Like

Therefore, when the size of the coil conductor is designed on the basis of the average temperature Tb when the maximum temperature is made to coincide with the maximum allowable temperature Tm which is the same reference as the conventional one, the average temperature Tb of this embodiment is Difference Δ from the average temperature Ta of the conventional example
It becomes higher by T, and the size of the coil conductor can be made smaller by this difference ΔT. Therefore, it is possible to reduce the size and weight of the entire transformer. However,
If the size of the coil conductor is made smaller, the amount of heat generated will increase accordingly, and this must be taken into consideration. Moreover, according to the second embodiment shown in FIG. 4, since the coil 1 can be cooled more effectively by the heat pipe 7, the size of the coil conductor can be set to be smaller, and the entire transformer can be reduced. Further downsizing and weight reduction can be achieved.

In this embodiment, the outer peripheral portion 1a of the coil 1 is
Although two heat pipes 4 and 5 are inserted in the inner peripheral portion 1b and the inner peripheral portion 1b respectively, the number of heat pipes to be inserted need not be two, and the evaporation portions 4a and 4a, 5a and 5a of the heat pipes 4 and 5 are connected to each other. A single elliptical heat pipe may be used.
The same applies to the heat pipe 7 of the second embodiment.

FIGS. 5 (a) and 5 (b) show a third embodiment of the present invention. The same parts as those in FIGS. 1 (a) and 1 (b) are designated by the same reference numerals and their description is omitted. Only different parts will be described below. Although the illustration of the inner peripheral portion 1b side of the coil 1 is omitted, the coil 1 has the same configuration. In the third embodiment shown in FIG. 5A, the heat pipe 8 is inserted between the outer peripheral portion 1a of the coil 1 and the insulator 3a so as to extend along the winding direction of the coil conductor. Both ends of this heat pipe 8 are arranged on the outer peripheral portion 1c of the coil 1 which is a non-contact portion with the insulator 3a, and these constitute the condenser portions 8a, 8a. Also, coil 1
The central portion of the heat pipe 8 which is in contact with the outer peripheral portion 1a of the above constitutes an evaporation portion 8b. Further, both end portions of the heat pipe 8 and the outermost peripheral portion of the coil 1 are electrically connected to each other without being insulated at their contact portions.

Next, the operation of the third embodiment will be described. The current flowing through the coil 1 also branches into the heat pipe 8 at the outermost periphery of the coil 1. Therefore, it can be considered that the coil conductor has a large cross-sectional area at that portion. Here, the heat generated by energizing the conductor is obtained by the following equation. Q = I ² · ρ · L / S Q is the amount of heat generation, I is the current, ρ is the specific resistance of the conductor, L is the length of the conductor, and S is the cross-sectional area of the conductor. That is, the heat generated in the conductor is inversely proportional to the cross-sectional area S of the conductor. Therefore, in the outermost peripheral portion of the coil 1 having the highest temperature, the heat is transferred to the relatively low temperature portion by the heat pipe 8 to be cooled, and the heat generation itself is also suppressed by the increase in the cross-sectional area of the conductor. Become.

The operation relating to cooling is substantially the same as that of the first embodiment, and the high temperature heat generated in the outer peripheral portion 1a is collected by the evaporating portion 8b of the heat pipe 8 and the working liquid therein causes the outer peripheral portion 1c. It is transported to the condensing part 8a in the vicinity and is radiated in a relatively low temperature part where the insulating oil 17 is satisfactorily cooled.

As described above, according to the third embodiment, the heat pipe 8 is arranged on the outer peripheral portion 1a of the coil 1, and the condenser portions 8a, 8a at both ends thereof are electrically connected to the outer peripheral portion of the coil 1. By doing so, the outer peripheral portion of the coil 1 can be cooled and the amount of heat generated can be suppressed.

FIGS. 6 (a) and 6 (b) show a fourth embodiment of the present invention. The same parts as those in FIGS. 1 (a) and 1 (b) are designated by the same reference numerals and their description is omitted. Only different parts will be described below. In this embodiment as well, the illustration of the inner peripheral portion 1b side of the coil 1 is omitted, but the coil 1 has the same configuration. In FIG. 6 (a), instead of the heat pipe 4 used in the first embodiment, one heat pipe 9 is attached so as to be wound around the outer peripheral portion 1 a of the coil 1,
The insulator 12 having a U-shaped cross section is fitted and attached.

One end of the heat pipe 9 is electrically connected to the lead-out portion 6a of the coil 1, and the other portion is insulated from the outer peripheral portion 1a of the coil 1. In the heat pipe 9, the portion arranged on the outer peripheral portion 1a of the linear portion of the coil 1 constitutes the evaporation portion 9a, and the portions arranged on both ends and the outer peripheral portion 1c of the coil 1 are the condensation portion. 9b. Further, as shown in FIG. 4B, the cross section of the heat pipe 9 has a D-shape whose bottom is the contact surface with the coil conductor.

Next, the operation of the fourth embodiment will be described. Since the outer peripheral portion 1a of the coil 1 is close to the ground electrode portion, the electric field is concentrated at the corners of the conductor having a rectangular cross section, and corona discharge is likely to occur. Therefore, the outer peripheral portion is wound and covered with a heat pipe 9 having a D-shaped cross section and a curved surface having a small curvature, and the end portion of the heat pipe 9 is electrically connected to the coil 1 so as to connect them to each other. By setting the potential, the electric field with respect to the ground is relaxed, and corona discharge is less likely to occur.

The operation relating to the cooling is substantially the same as that of the first embodiment, and the high temperature heat generated in the outer peripheral portion 1a is collected by the evaporating portion 9a of the heat pipe 9 and the working liquid therein causes the outer peripheral portion 1c. It is transported to the condensing part 9b arranged in the vicinity and is radiated in a relatively low temperature part where the insulating oil 17 is satisfactorily cooled.

As described above, according to the fourth embodiment, one end portion of the heat pipe 9 arranged so as to be wound around the outer peripheral portion of the coil 1 is electrically connected to the coil 1 so that the high temperature portion of the coil 1 is It is possible to suppress the occurrence of corona discharge at the corners of the conductors that form the coil 1 while cooling.

FIG. 7 shows a fifth embodiment of the present invention. FIG. 7 shows the structure of a part of the outer circumference of the coil 11. A part of the outermost peripheral portion of the coil 11 is composed of the heat pipe 10 having the same size as the coil conductor. Both ends of the heat pipe 10 forming the condensing portion 10b are provided at positions protruding from the portion covered with the insulator 3a as in the first embodiment, and are electrically connected to the conductors of the coil 11, respectively. There is. In addition, the insulator 3a of the heat pipe 10
The central portion covered by the above constitutes an evaporation portion 10a.

Next, the operation of the fifth embodiment will be described. In the above-described first to fourth embodiments, the heat pipe is inserted between the peripheral portion of the coil and the insulator or between the windings of the coil conductor. However, when the heat pipe is inserted as described above, the width dimension W of the coil and the heat pipe shown in FIG. 1 is increased accordingly. Therefore, as in the fifth embodiment, the coil 1
By configuring the high temperature portion of No. 1 by the heat pipe 10, the portion covered by the insulator 3a and having the high temperature can be cooled without increasing the width dimension W.

The operation relating to cooling is substantially the same as that of the first embodiment, and the evaporation section 10a of the heat pipe 10 is
The high-temperature heat generated in 1 is not covered with the insulator 3a by the working fluid therein, but is arranged in a relatively low-temperature portion where it is cooled well with insulating oil.
It is transported to b and radiated.

As described above, according to the fifth embodiment, the central portion which constitutes the evaporation portion 10a is arranged in a portion where a part of the coil 11 is covered with the insulator 3a and has a relatively high temperature. A heat pipe 1 in which both ends of the condensing part 10b are arranged in a part which is not covered with the air and has a relatively low temperature.
0, and both ends thereof are electrically connected to the conductors of the coil 11, so that the width dimension W of the coil is not increased by inserting the heat pipe.
Can be cooled.

When the transformer is constructed as in the first to fifth embodiments, the coil conductor may be made of aluminum to reduce the weight of the transformer. Aluminum has a small thermal conductivity of about 60% that of copper, and in conventional cooling methods, the tendency for heat to concentrate in the high-temperature parts becomes remarkable, so aluminum can be used. There wasn't.

However, as in the first to fifth embodiments of the present invention, if the heat of the high temperature portion of the coil is transported to the relatively low temperature portion and radiated by the heat pipe, the evaporation portion Because the heat concentration of
Aluminum can be used as the coil conductor, and the weight of the coil can be reduced, so that the weight of the transformer can be further reduced.

[0048]

As is apparent from the above description, the present invention has the following effects. According to the transformer of claim 1, the heat of the portion of the coil having a relatively high temperature is transferred to the cooling medium or the portion of the coil having a low temperature by the heat pipe to average the temperature distribution inside the transformer. Since the high temperature portion of the coil is cooled by the action of becoming heat, it is not necessary to interpose an insulator between the coil and the heat pipe, and heat is efficiently transported by the heat pipe. The size of the coil conductor can be reduced by the amount of cooling, and the transformer can be made compact and lightweight.

According to the transformer of the second aspect, the heat collected in the part of the heat pipe arranged in the high temperature part of the coil is arranged in the cooling medium or in the low temperature part of the coil. Since heat is radiated at both ends of the heat pipe, the coil can be cooled more effectively.

According to the transformer of the third aspect, the current of the coil is shunted to the heat pipe electrically connected, so that the heat generation amount of the coil conductor portion is reduced accordingly, and the high temperature of the coil is increased. The temperature of the part that becomes is further decreased.

According to the transformer of the fourth aspect, the heat pipe alleviates the electric field to the ground electrode portion on the outer peripheral portion of the coil, thereby suppressing the generation of corona discharge.

According to the transformer of the fifth aspect, since the coil can be formed in a small size by forming a part of the coil with the heat pipe, a space for arranging the heat pipe is required inside the transformer. Without doing so, the transformer can be made smaller.

According to the transformer of the sixth aspect, since the coil is lightened by forming the coil conductor with aluminum, the weight of the transformer can be further reduced.

[Brief description of drawings]

1A is a plan view of a transformer showing a first embodiment of the present invention, and FIG. 1B is a side view thereof.

FIG. 2 is a diagram showing a temperature distribution in a cross section of a coil.

[Fig. 3] Temperature distribution chart compared with the conventional one

FIG. 4A is a plan view showing a second embodiment of the present invention,
(B) is a partial sectional view

FIG. 5 (a) is a plan view showing a third embodiment of the present invention,
(B) Side view

FIG. 6A is a plan view showing a fourth embodiment of the present invention,
(B) is a partial sectional view

FIG. 7 is a perspective view showing a main part of a fifth embodiment of the present invention.

[Description of Reference Signs] 1, 11 are coils, 2 are iron cores, 3a, 3b are U-shaped cross-section insulators, 4, 5, 7 to 10 are heat pipes, 4a, 5
a, 7a to 10a are evaporation sections, 4b, 5b, 7b to 1
Reference numeral 0b indicates a condenser, and 17 indicates insulating oil (cooling medium).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hisashika Yasuda 2121 Nobu, Asahi-cho, Mie-gun, Mie Prefecture

Claims (6)

[Claims] 1. A coil formed by winding a coil conductor into a plate shape, a heat pipe provided in contact with a peripheral portion of the coil or located between the coil conductors, and flowing along a plate surface of the coil. And a cooling medium, the heat pipe is provided so as to extend along the winding direction of the coil conductor, the evaporation portion thereof is located at a portion of the coil where the temperature is relatively high, and the condensing portion is A transformer characterized in that it is arranged in a cooling medium or in a portion of the coil where the temperature is low. 2. The heat pipe is configured so as to pass through a high temperature portion of the coil and have both ends located in the cooling medium or in a low temperature portion of the coil. The listed transformer. 3. The transformer according to claim 2, wherein both ends of the heat pipe are electrically connected to a coil conductor. 4. A coil comprising a coil conductor wound in a plate shape, a heat pipe provided in contact with a peripheral portion of the coil, and a cooling medium flowing along a plate surface of the coil. The heat pipe is provided so as to extend along the winding direction of the coil conductor, the evaporation portion thereof is located at a portion where the temperature of the coil is relatively high, and the condensation portion is in the cooling medium or the low temperature of the coil. The outer circumference of the cross section is formed with a curvature smaller than that of the cross section of the coil conductor, and a part of the cross section is electrically connected to the coil conductor. Characteristic transformer. 5. A coil comprising a coil conductor, a part of which is formed of a heat pipe, wound in a plate shape, and a cooling medium flowing along a plate surface of the coil, wherein the heat pipe of the coil comprises: A transformer characterized in that the evaporator is located at a portion of the coil that is relatively hot, and the condenser is located in the cooling medium or at a portion of the coil that is cold. 6. The transformer according to claim 1, wherein the coil conductor is made of aluminum.