JP2017184357A - Power conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion device capable of suppressing influence of steam and smoke without increasing the size.SOLUTION: A power conversion device includes a housing 1 in which an electric circuit for converting DC power into AC power is housed, and a fitting plate 16 which is configured to cool heat generating components 12 and 13 constituting the electric circuit in the process that air entering from a suction hole 9 of a lower wall 3 of the housing 1 exits from a discharge hole 10 of an upper wall 4, and mounts the housing 1 to the wall of a house. The fitting plate 16 is provided with a shielding plate 21 at least a part of which faces the suction hole 9 at a position spaced downwardly at a predetermined distance from the suction hole 9.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power conversion device attached to a wall surface of a house, and more particularly to a shielding plate for suppressing intrusion of steam or smoke from an air suction hole of a housing.

An electrical circuit that converts DC power into AC power is housed in the housing, and an exothermic component that forms the electrical circuit in the process of air entering from the suction hole on the lower wall of the housing exiting from the discharge hole on the upper wall There is known a power conversion device configured to perform the above cooling.
In such a power conversion device, when steam or smoke enters the housing from the suction hole, for example, if steam condenses on a heat-generating component or other electrical component in the process of passing through the housing, these components have poor insulation. It sometimes occurred. Similarly, when smoke enters the housing, these components may lead to poor insulation.

There existed what was described in patent document 1 in the countermeasure against the vapor | steam invading a housing | casing. For example, a heat-generating component (heat-generating component) is covered and sealed so that steam does not condense on the component.

JP 2015-223025 A

In the device described in Patent Document 1, heat-generating components (heat-generating components) and other electrical components are individually or collectively covered with a cover to prevent dew condensation on each component. In such a configuration, it is difficult to reduce the size in terms of structure, and there is a problem that a configuration such as a cooling fan is required to sufficiently cool these components.

As a result, the power converter becomes heavier and larger, and for example, when it is attached to the wall of a dressing room adjacent to the bathroom, a sufficient installation space cannot be secured, which may hinder the installation of the power converter. It was. In addition, the exothermic parts may not be sufficiently cooled only by natural circulation of air.

The power conversion device of the present invention accommodates an electric circuit for converting DC power into AC power in a housing, and in the process in which air entering from the suction hole on the lower wall of the housing exits from the discharge hole on the upper wall. In the power conversion device configured to cool the heat-generating parts constituting the electric circuit, the power conversion device includes a mounting plate for mounting the housing on the wall surface of the house, and the mounting plate is at least at a position separated by a predetermined distance from the suction hole. A part is provided with a shielding plate facing the suction hole.

The power conversion device of the present invention is provided with a natural circulation that enters the housing from the suction hole by providing the shield plate at a position that is a predetermined distance below the suction hole while suppressing steam and smoke entering from the suction hole by the shield plate. It is possible to ensure the amount of air.

FIG. 1 is an explanatory diagram of a power converter according to an embodiment of the present invention. FIG. 2 is an explanatory diagram of a lower wall of the power conversion device illustrated in FIG. 1. FIG. 3 is an explanatory diagram of an upper wall of the power conversion device illustrated in FIG. 1. FIG. 4 is an explanatory diagram of the back wall of the power conversion device shown in FIG. 1. FIG. 5 is an explanatory view showing a state in which the shielding plate is attached to the attachment plate. Drawing 6 is an explanatory view at the time of attaching the back wall of a power converter to a mounting plate. FIG. 7 is an explanatory view showing another embodiment. FIG. 8 is an explanatory view showing another embodiment.

In the present invention, a shield plate is detachably provided on a mounting plate when the power conversion device is mounted on a wall surface, and steam and smoke are prevented from entering from the intake hole.

FIG. 1 is an explanatory diagram of a power conversion device according to an embodiment of the present invention. A casing 1 has at least a back wall 2 and a lower wall 3 and an upper wall 4 that are raised so as to surround the back wall 2. The right wall 5, the left wall 6, and the front panel 7 which is detachably attached from the front side.
The back wall 2, the lower wall 3, the upper wall 4, the right wall 5, and the left wall 6 are made by bending and joining metal plates and painting, those made by drawing colored steel plates, synthetic Since materials integrally formed with resin can be used, materials, manufacturing methods, and the like are not limited. The housing 1 may have any configuration that can accommodate an electrical circuit, a heat-generating component, and the like which will be described later. Similarly, the material and processing method of the front panel 7 are not limited, but in the present invention, an integrally molded product of synthetic resin will be described as an example.

An electrical circuit that converts DC power into AC power is housed in the housing 1, and air that enters the suction hole 8 and suction hole 9 of the lower wall 3 of the housing 1 is discharged from the discharge hole 10 of the upper wall 4. In the process of exiting from the hole 11 (not shown in FIG. 1), the exothermic parts constituting the electric circuit are cooled. The electric circuit converts DC power supplied from a DC power source such as a solar cell, a fuel cell, or a storage battery into AC power having a frequency synchronized with, for example, the system.

For example, if the electrical circuit for this conversion is a single phase, four switching elements are connected in a bridge shape, and these switching elements are turned on / off based on a PWM (pulse width modulation) system.
What obtains a pseudo sine wave by FF control can be used. The electric circuit is not limited to this, and a neutral point clamping method, a gradation method, an output clamping method, or the like may be used. In addition, a low-pass filter that attenuates or substantially removes the high-frequency component of the pseudo sine wave before any system is connected to the system is provided.

The low-pass filter includes at least reactors 12 and 13 and a capacitor (not shown), and the reactors 12 and 13 generate heat due to iron loss, copper loss, and the like. Therefore, the heat generating components constituting the electric circuit of the present invention include the reactors 12 and 13. In FIG. 1, a switching element constituting an electric circuit for conversion to AC power is attached to the heat sink 14 to dissipate the heat generated. The switching element may be a module 15 in which a plurality of switching elements are housed in a single package. Accordingly, the heat generating components constituting the electric circuit of the present invention include these switching elements and the module 15.

FIG. 2 is an explanatory diagram of the lower wall 3, and FIG. 4 is an explanatory diagram of the upper wall 4. Referring to FIG. 1, a plurality of air paths composed of a plurality of heat radiating fins arranged in parallel to the heat sink 14 are formed in the suction hole 9 in the lower wall 3 in the housing 1 and the discharge hole 11 in the upper wall 4. And is configured between. Therefore, cooling of the heat-generating parts (module 15 attached to the heat sink 14) constituting the electric circuit is performed in the process in which the air entering from the suction hole 9 of the lower wall 3 of the housing exits from the discharge hole 10 of the upper wall 4. .
When the heat sink 14 is heated, the temperature in the air passage rises, and the air that has entered from the suction hole 9 naturally circulates to the discharge hole 11 by the rising airflow. The suction hole 9 and the discharge hole 11 are composed of a plurality of slit-shaped holes, and these slits correspond to the air path between the heat radiation fins of the heat sink 14.

Further, between the suction hole 8 and the discharge hole 10, reactors 12 and 13 which are heat generating components in the left mold in the housing 1 in FIG. Therefore, cooling of the heat-generating parts (reactors 12 and 13) constituting the electric circuit is performed in the process in which the air that has entered from the suction hole 8 of the lower wall 3 of the housing exits from the discharge hole 11 of the upper wall 4. The suction hole 8 and the discharge hole 10 are formed of a mesh. A part of the air that has entered through the suction hole 8 is exhausted from the discharge hole 10 by cooling other electrical components such as an electrical board (not shown).

The electrical circuit in the housing 1 also uses electrical components such as capacitors, resistors, and relays.
You may comprise an air path so that the air which entered from the suction hole 8 may cool these electric components by natural circulation.

FIG. 4 is an explanatory diagram of a state in which the back wall 2 is viewed from the outside of the housing 1, and a state in which the mounting plate 16 is fitted in the locking portion 17. The back wall 2 is provided with openings 19a and 19b.
19 b faces the air path formed between the heat radiation fins 18 of the heat sink 14. Back wall 2
Is attached to the wall surface of the house via the attachment plate 16, and the air passage becomes substantially cylindrical and the tunnel effect is likely to occur. At the same time, air can be supplied from the openings 19a and 19b to the air passage, and the air suction amount of the suction hole 9 can be compensated. Reference numeral 20 denotes a lead-in port for drawing the wiring of the DC power supplied from the DC power supply or the wiring of the AC power output to the system into the housing 1.
This service port 20 may be used for receiving a signal line.

FIG. 5 is an explanatory diagram of a state in which the shielding plate 21 is attached to the attachment plate 16. The shielding plate 21 is fastened together with the attachment plate 16 to the wall surface using screw holes 22a and 22b used when the attachment plate 16 is attached to the wall surface. The The shielding plate 21 is formed by bending a sheet metal into a leg portion 21a and a shielding plate portion 21b. The shielding plate portion 21b only needs to have a size such that at least a part thereof opposes the suction hole 8 of the lower wall 3 of the housing 1. The shielding plate 21 may be integrally formed of synthetic resin. Further, it may be configured to be foldable to improve convenience.

The shielding plate portion 21b only needs to have an area that is substantially the same as the projected area of the lower wall 3 or that is slightly smaller than the projected area. There is no problem even if this area is slightly larger than the projected area of the lower wall 3, but if it is too large, the design effect is deteriorated, and the air suction effect of the suction holes 8 and 9 is hindered. The leg portion 21a is arranged such that the shielding plate portion 21b is separated from the suction hole 8 by a predetermined distance L below the length thereof. In order to maintain this predetermined distance L, the mounting plate 16 and the shielding plate 21 are fastened together.

Since the shielding plate 21 can be detached from the mounting plate 16 unless it is fastened together, the shielding plate 21 is substantially detachably attached to the mounting plate 16. Moreover, since the attachment / detachment position of the mounting plate 16 and the shielding plate 21 is located between the back wall 2 and the wall surface 23, it is possible to prevent the shielding plate 21 from being removed by an inadvertent operation after the power converter is attached. When installing the power converter (housing 1) in a place where there is little influence of steam or smoke, the shielding plate 2 is attached before the housing 1 is attached to the mounting plate 16.
Do not tighten 1 together. In this case, the air suction effect of the suction holes 8 and 9 is not hindered.

FIG. 6 is an explanatory diagram when the back wall 2 of the power converter is attached to the attachment plate 16. In the house,
For example, the attachment plate 16 is screwed and attached to a place above a wall surface 23 of a dressing room adjacent to the bathroom and where there is a solid structure such as a pillar. (The mounting plate 16 has a plurality of screw holes, and a suitable screw hole can be selected in accordance with the position of the structure.) Next, the shielding plate 21 and the mounting plate 16 are jointly connected using the screw holes 22a and 22b. Tighten. Thereafter, the locking portion 17 of the back wall 2 is hung on and fixed to the claw portion 16 a of the mounting plate 16. At this time, a part of the housing 1 may be screwed to the mounting plate 16 and fixed.

When the shield plate 21 is provided in this way, when steam or smoke rises from below, the steam or smoke hits the shield plate 21 and the upward direction is bent away from the suction holes 8 and 9 of the power converter. Therefore, steam and smoke can be prevented from entering the housing through the suction holes 8 and 9. Further, since the shielding plate 21 is provided at a position that is a predetermined distance below the suction holes 8 and 9, the air between the shielding plate 21 and the suction holes 8 and 9 causes steam to enter the housing 1. Infiltration is suppressed. When there is no steam, air can be supplied into the housing 1 through the space between the shielding plate 21 and the suction holes 8 and 9.

The predetermined distance L between the shielding plate 21 and the suction holes 8 and 9 is set appropriately in consideration of the standing condition of steam (the amount and time of steam), the amount of air required for cooling the heat-generating components, and the like. For example, when installing a power converter in a dressing room, it sets according to the installation position and the condition of steam when the bathroom door is opened. Therefore, it is possible to adjust the predetermined distance by changing the screw hole when the shield plate 21 is fastened to the mounting plate 16 together. Further, a configuration that can change the predetermined distance separately may be added.

7 and 8 are explanatory views of a shielding plate showing another embodiment. FIG. 7 shows the leg 21 of the shielding plate 21.
A screw hole 21d in a state where the upper tip 21c of a and the lower tip 16b of the mounting plate 16 are abutted against each other
, 21e are shown in a screwed state. A predetermined distance is maintained by abutting the upper tip 21c and the lower tip 16b. Further, if the shielding plate 21 is maintained without being inclined, there may be a gap between the upper tip 21c and the lower tip 16b, and the effects of the present invention can be obtained similarly. In addition, the leg part 21a may be plural in the present invention, and may be formed in a planar shape with the same width as the mounting plate 16. FIG. 8 shows a shielding plate 21
The shielding plate portion 21b is a mesh structure portion 21f. It suffices that the mesh structure has a size that keeps steam.

The shielding plate 21 may be made of a sheet metal integrally with the mounting plate 16. In this case, the shielding plate portion may have a folding structure in consideration of convenience.

The power converter of the present invention can be applied to a mounting plate for mounting the power converter in a place where steam or smoke is present.

As mentioned above, although one Embodiment of this invention was described, the above description is for making an understanding of this invention easy, and does not limit this invention. It goes without saying that the present invention can be changed and improved without departing from the gist thereof, and that the present invention includes equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Housing | casing 2 Back wall 3 Lower wall 4 Upper wall 8 Suction hole 9 Suction hole 10 Ejection hole 11 Ejection hole 12 Reactor 13 Reactor 14 Heat sink 15 Module 16 Mounting plate 21 Shielding plate 21a Leg part 21b Shielding plate part

Claims (4)

An electric circuit for converting DC power into AC power is housed in the housing, and the heat generated in the electric circuit in the process of air entering from the suction hole in the lower wall of the housing exiting from the discharge hole in the upper wall In the power converter configured to cool the functional parts,
The mounting plate includes a mounting plate for mounting the housing on a wall surface of the house, and the mounting plate includes a shielding plate that is at least partially opposed to the suction hole at a position spaced apart from the suction hole by a predetermined distance. Power converter. The power conversion device according to claim 1, wherein the shielding plate is detachably attached to the attachment plate. The housing includes at least a back wall and the lower wall, the upper wall, the right wall, and the left wall raised so as to surround the back wall, and the back wall is configured to be attachable to the mounting plate. The power converter according to claim 2, wherein an attachment / detachment position between the mounting plate and the shielding plate is provided between the back wall and the wall surface. The power converter according to claim 1, wherein the shielding plate is configured integrally with the mounting plate.

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