JP3777641B2 - Power converter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat dissipation mechanism of a power conversion device using a semiconductor switching element.
[0002]
[Prior art]
A conventional power conversion device will be described below with reference to FIG. This power converter 1 is used for induction heating of a cooking pan 2 or the like placed on top by generating a high-frequency magnetic field. The induction heating coil 3 that generates a high-frequency magnetic field is supplied with a high-frequency current from a high-frequency inverter 4. Reference numeral 5 denotes a switching element that constitutes a part of the high-frequency inverter 4 and converts the commercial power source into high-frequency power. Since the switching element 5 generates switching loss and generates heat during the switching operation, it is cooled by the radiation fins 6. Reference numeral 7 denotes a fan that cools the entire power conversion apparatus 1.
[0003]
With the above configuration, the switching element 5 switches the commercial power source to a high frequency, and the high frequency inverter 4 supplies a high frequency current to the induction heating coil 3. When the high frequency magnetic field generated from the induction heating coil 3 is linked to the cooking pot 2, the cooking pot 2 made of a magnetic material is induction-heated and generates heat. Thus, the food in the cooking pan 2 is heated and cooking proceeds.
[0004]
[Problems to be solved by the invention]
The conventional power converter has a problem that the cooling of the switching element 5 is not sufficient and the fan 7 being used becomes large.
[0005]
An object of the present invention is to solve the problem of such a conventional configuration, and to provide a power conversion device that can sufficiently cool a switching element with a simple configuration.
[0006]
[Means for Solving the Problems]
According to the first means of the present invention, heat generated by a plurality of switching elements is radiated by the shielding plate connected to the housing, and cooling using the heat capacity of the entire casing can be performed, and there is no need to provide a radiating fin. The power conversion device can be simplified in configuration.
[0007]
The second means of the present invention is a power conversion device that radiates heat with the first radiating fin and the shielding plate connected to the casing, and that can radiate the heat efficiently with a simple configuration.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
The first embodiment of the present invention will be described below. FIG. 1 is a cross-sectional view showing the overall configuration of a power conversion device showing the configuration of the present embodiment. The power converter 8 includes a high-frequency inverter 11 that generates a high-frequency magnetic field and supplies a high-frequency current to an induction heating coil 10 that induction-heats the cooking pot 9 placed on the top. Reference numeral 12 denotes a switching element for converting commercial power into high frequency, and constitutes a part of the high frequency inverter 11. The switching element 12 switches commercial power at high speed, and the heat generated by this switching is very large. In this embodiment, the switching element 12 is attached to the radiation fin 13 and radiates heat as shown in FIG. The switching element 12 used at this time is electrically insulated from the heat radiating fins 13. A part of the radiating fin 13 is exposed to the outside of the housing 14 and is directly cooled by the outside air. Reference numeral 15 denotes a fan that cools the entire high-frequency inverter 11.
[0009]
The operation of this embodiment will be described below. When a cooking start button (not shown) is pressed, the high frequency inverter 11 starts operating and the induction heating coil 10 generates a high frequency magnetic field. This high frequency magnetic field is linked to the cooking pot 9 placed on the upper portion, and the cooking pot 9 is induction-heated. Accordingly, the food in the cooking pan 9 is heated and cooking proceeds. At this time, the switching element 12 constituting a part of the high-frequency inverter 11 switches the commercial power supply at a high speed to convert the power to a high frequency, generates heat, and has a high temperature. In the present embodiment, since the switching element 12 is attached to the heat radiating fin 13, the heat generation of the switching element 12 can be effectively suppressed. That is, since a part of the radiation fin 13 is exposed to the outside of the housing 14, it is directly cooled by the outside air.
[0010]
Therefore, according to this embodiment, the switching element 12 is attached to the radiating fin 13 that is arranged so as to be exposed outside the casing, and the radiating fin 13 itself is cooled by the outside air. It is possible to realize a power conversion device that can be cooled down. As a result, it is sufficient that the cooling fan 15 used is smaller than the conventional one.
[0011]
At this time, as shown in FIG. 3, if a plurality of switching elements 12 connected in parallel to one radiating fin 13 are attached, even a power conversion device that flows a larger current has a simple configuration. I can do it.
[0012]
Further, at this time, as shown in FIG. 4, if both the surfaces of the plurality of switching elements 12 are radiated by the radiation fins 13a and 13b, the switching elements can be cooled even in a power conversion device through which a large current flows. Will be sufficient. Of course, in this case, both of the two radiating fins 13 are exposed to the outside of the casing 14 and are directly cooled by the outside air.
[0013]
At this time, if the heat radiation fins 13 are exposed at the bottom of the housing 14 as shown in FIG. 5, the human body may touch the heat radiation fins 13 having a sufficient cooling effect and high temperature. It is possible to realize a power conversion device without any problem.
[0014]
In addition, as shown in FIG. 1, when the heat radiation fins 13 are exposed to the side portions of the housing 14, the heat radiation fins 13 are in good contact with the outside air and have a high cooling effect. A device can be realized.
[0015]
(Embodiment 2)
Next, a second embodiment of the present invention will be described. FIG. 6 is a cross-sectional view showing the overall configuration of the present embodiment. Reference numeral 12 denotes a plurality of switching elements that convert commercial power into high frequency, and constitutes a part of the high frequency inverter 11 that supplies high frequency current to the induction heating coil 10. In this embodiment, four switching elements 12 are used, and are attached to one first radiation fin 16. Further, as shown in FIG. 7, a cooling plate 19 to which a heat pipe 18 is attached is attached to the upper surface of each switching element 12. The cooling plate 19 is made of a metal having high thermal conductivity such as aluminum. Further, the end of the heat pipe 18 is connected to a second radiating fin 17 provided so as to be exposed from the housing 14.
[0016]
The operation of this embodiment will be described below. The switching element 12 is a package type, and is insulated from the first radiating fins 16 and the cooling plate 19. The high-frequency inverter 11 of the present embodiment uses four switching elements 12, and the four switching elements are cooled by a first radiating fin 16, a second radiating fin 17, and a heat pipe 18. Is what you are trying to do. That is, one surface of the switching element 12 is in contact with the first radiation fin 16, and the other surface is a second radiation fin by the heat pipe 18 through the cooling plate 19 made of metal such as aluminum having high thermal conductivity. Heat is transferred to 17. Therefore, the four switching elements 12 are cooled from both sides, and as a result, heat generation can be suppressed to a very low level.
[0017]
As described above, according to the present embodiment, since the heat generated by the plurality of switching elements 12 is radiated by the first radiating fins 16, the heat pipes 18, and the second radiating fins 17, the plurality of switching elements 12. Therefore, the cooling fan required for the high-frequency inverter 11 can be made smaller or unnecessary than before.
[0018]
In particular, according to the present embodiment, since the second radiating fins 17 are disposed so as to be exposed to the outside of the housing 14, the cooling effect can be further enhanced.
[0019]
At this time, if the cooling of the switching element 12 is configured as shown in FIG. 8, it is not necessary to provide a heat radiating fin, and a power conversion device with a simpler cooling configuration can be realized. That is, a cooling plate 19 having a heat pipe 18 attached thereto is attached to the switching element 12, and a cooling plate 20 is similarly attached to the other end of the heat pipe 18, and the cooling plate 20 is shielded from an electric or magnetic field. It is what is attached to. That is, the heat generated by the switching element 12 is radiated to the shielding plate 21 connected to the housing 14 by the heat pipe 18. That is, the switching element 12 can be cooled using the housing 14 having a very large heat capacity via the shielding plate 21.
[0020]
Further, at this time, the cooling configuration shown in FIG. 9 can achieve more effective cooling. That is, four switching elements 12 each having a cooling plate 19 attached thereto are attached to the radiation fins 13, and the other end of the heat pipe 18 is attached to the shielding plate 21 via the cooling plate 20 in the same manner as described in FIG. It is to be configured.
[0021]
【The invention's effect】
The first means of the present invention includes a switching element that converts a commercial power source into high frequency, a heat pipe that has one end connected to the switching element and the other end connected to a shielding plate that shields an electric field or a magnetic field, and the shielding plate. And a heat sink of the switching element, wherein the heat generated by the switching element is dissipated by the shielding plate connected to the case. It is not necessary to provide a power conversion device that can simplify the cooling configuration.
[0022]
The second means of the present invention includes a plurality of switching elements for converting a commercial power source into a high frequency, a first radiating fin to which these switching elements are attached, each of these switching elements connected to one end and the other end A heat pipe connected to a shielding plate that shields an electric field or a magnetic field and a casing connected to the shielding plate, and the heat generation of the switching element is radiated by the shielding plate connected to the casing , A power converter that can dissipate heat efficiently with a simple configuration can be realized.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a power conversion apparatus according to a first embodiment of the present invention. FIG. 2 is a perspective view showing a heat radiation fin to which switching elements are attached. FIG. FIG. 4 is a perspective view showing a radiation fin attached to both surfaces of a plurality of switching elements. FIG. 5 is a sectional view of a power conversion device showing the radiation fin exposed on the bottom of the housing. FIG. 6 is a cross-sectional view showing a power converter according to a second embodiment of the present invention. FIG. 7 is a perspective view showing cooling by the first radiating fin, the second radiating fin, and the heat pipe. Same perspective view showing cooling by shielding plate FIG. 9 Perspective view showing cooling by radiating fin and shielding plate FIG. 10 Cross sectional view showing configuration of conventional power conversion device
12 switching element 13 radiation fin 13a radiation fin 13b radiation fin 14 housing 16 first radiation fin 17 second radiation fin 18 heat pipe 21 shielding plate

Claims (2)

A switching element that converts commercial power into high frequency, a heat pipe that has one end connected to the switching element and the other end connected to a shielding plate that shields an electric or magnetic field, and a housing connected to the shielding plate , The power conversion device , wherein heat generated by the switching element is radiated by the shielding plate connected to the casing . A plurality of switching elements that convert commercial power to high frequency, a first radiating fin having these switching elements attached thereto, and a shielding plate that connects each of these switching elements to one end and shields the other end from an electric field or a magnetic field A power conversion device comprising: a heat pipe connected to the housing; and a housing connected to the shielding plate , wherein heat generated by the switching element is radiated by the shielding plate connected to the housing .

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