JP2012201138A - Forced air cooling type semiconductor cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact semiconductor cooling device capable of improving cooling performance by efficiently using cooling air by a cooling fan.SOLUTION: A first cooler 4 having a wide cooling air width with respect to a cooling air flow length and a second cooler 5 having a cooling air width smaller than that of the first cooler 4 are arranged so that cooling air directions are similar and no heat is exchanged therebetween. The semiconductor elements 7, 8 and 9 of an inverter circuit are attached to the first cooler 4, and the semiconductor element 10 of a brake chopper circuit is attached to the second cooler 5. Cooling air by a cooling fan 6 having a cooling air direction perpendicular to the cooling air direction of the cooler is distributed to the first cooler 4 and the second cooler 5 via a wind channel 2 having an air rectifying guide 3, and the heat exchange with the semiconductors is performed.

Description

  The present invention relates to a forced air cooling type semiconductor cooling device in a power conversion device installed, for example, on the roof or under the floor of a railway vehicle.

  The power conversion device for a railway vehicle requires a cooling device for radiating heat generated from the semiconductor element to the atmosphere and suppressing the temperature rise of the semiconductor element. In the case of a streetcar or a new transportation vehicle, a forced air cooling method is generally employed in which the cooling air is forcibly cooled without using the traveling wind.

  The structure of the semiconductor cooling device of the conventional forced air cooling type power converter is generally shown in FIGS. 3, 4 and 5. FIG. 3 shows a cooling system in which the cooling air from the cooling fan flows through a cooler having a narrow width with respect to the direction of the cooling air, and performs heat exchange. This is a cooling system that exchanges heat through a wide cooler.

  3A and 3B show a semiconductor cooling device using a cooler having a narrow width with respect to the cooling air direction. With this cooling method, since the cooling air from the cooling fan flows directly to the cooler, there is no need to provide a rectifying wind tunnel between the cooler and the cooling fan, and the cooling method can realize a simple cooling structure. Since the cooling structure design of the power conversion device is relatively simple, this method is often employed. (For example, refer to Patent Document 1.)

  FIG. 4A and FIG. 4B show a semiconductor cooling device (one) that uses a cooler having a wider width than the cooling air direction. The cooling method shown in FIG. 3 is a method in which a plurality of cooling fans are used and cooling air is blown directly to the cooler, so that it is not necessary to provide a rectifying wind tunnel between the cooler and the cooling fan.

  FIG. 5 (a) and FIG. 5 (b) show a semiconductor cooling device (2) using a cooler having a wide width with respect to the cooling air direction. The cooling system shown in FIG. 4 is a cooling system that uses a small number of cooling fans and blows cooling air to the cooler through the rectifying wind tunnel.

Japanese Patent Laid-Open No. 10-023768 (page 6, FIG. 1)

  Railroad car power converters not only perform power conversion by power running, but also use electric braking (regenerative braking) to convert kinetic energy into electric power and regenerate it to the overhead line during braking to save energy and reduce maintenance. However, since the electric power is consumed by the brake resistor and electric braking (power generation braking) is performed even when the regeneration expires, the heat generation of the power converter increases. Further, as the capacity of the motor is increased, the capacity of the power conversion device is increased and the heat generation is further increased. On the other hand, miniaturization and weight reduction of power converters are also required.

  In the case of the conventional cooling system as shown in FIG. 3, due to the heat radiation of each semiconductor, the cooler generates a temperature gradient in which the temperature gradually increases from the cooling air intake side toward the exhaust side, and is close to the exhaust side. The temperature of the semiconductor is higher than that of the semiconductor close to the intake side. As the cooling wind direction length of the cooler extends, the temperature gradient increases, and the heat capacity of the cooler cannot be fully utilized, resulting in poor cooling efficiency. Of course, since the performance of the cooler is determined by the temperature of the semiconductor disposed on the exhaust side having the worst cooling conditions, the shape of the cooler becomes large, which is disadvantageous in terms of downsizing, weight reduction, and cost of the cooling device. In addition, compared with a cooler having a wide width with respect to the cooling air direction, the temperature rise ratio (thermal resistance) with respect to the processing heat generation becomes large due to the problem of temperature gradient in the same outer shape, so the ability to suppress the temperature rise of the semiconductor is low. It will be a thing.

  In the case of the conventional cooling system as shown in FIG. 4 and FIG. 5, the temperature gradient of the cooler is small, and the temperature rise of each semiconductor is almost the same in the same outer shape, so the outer shape of the cooler is kept small, This is very advantageous for reducing the size and weight of the cooler. In addition, as compared with a cooler having a narrow width with respect to the cooling air direction, under the same cooling air condition as the same outer shape, the thermal resistance is reduced, so that the ability to suppress the temperature rise of the semiconductor is high.

  On the other hand, in the cooling method as shown in FIG. 4, when a plurality of cooling fans are used, the cooling air is blown directly to the cooler without using the rectifying wind tunnel, but the number of cooling fans is large. Cost and noise are difficult to reduce, and cooling air cannot be used efficiently. In addition, when one cooling fan stops, the temperature rise of the semiconductor in the part where the cooling fan has stopped becomes higher than that of the healthy part of the cooling fan, so the temperature rise becomes abnormally high and the power conversion device The possibility of having to stop is generated.

  In the cooling method as shown in FIG. 5, when the cooling air is blown out through the rectifying wind tunnel using a small number of cooling fans, the cooling air can be efficiently used. Since the shape greatly increases, it is very disadvantageous for miniaturization of the power conversion device.

  The present invention has been made to cope with the above-described situation, and its problem is to improve the cooling performance and reduce the size of the cooling device, thereby reducing the size and weight of the power conversion device. Is to provide.

  In order to solve the above-described problem, according to the invention of claim 1, in the power conversion device attached to the underfloor device of the railway vehicle, the first cooler having a wide cooling air width with respect to the cooling ventilation surface, A first wind tunnel for accommodating a second cooler having a cooling air width narrower than that of the first cooler so that the cooling air directions of the coolers are the same and do not exchange heat with each other; and A cooling fan having a cooling air direction perpendicular to the cooling fan, and a second wind tunnel provided with a wind regulation guide for distributing the cooling air of the cooling fan to the first and second coolers. It is characterized by comprising.

  That is, a first cooler having a cooling air width wider than the cooling air flow length, a second cooler having a cooling air width narrower than the cooler, and these coolers have the same cooling air direction and mutual A cooling fan having a cooling air direction perpendicular to the cooling air direction of the cooler, a wind tunnel for concentrating the cooling air of the cooling fan in the cooler, and a first cooler in the wind tunnel And a wind guide that distributes the cooling air to the second cooler.

  In addition, by distributing the cooling air from the cooling fan through the wind tunnel having the air conditioning guide, the first cooler and the second cooler are provided with a necessary air volume for suppressing the temperature rise of the semiconductor to cool the semiconductor element. I do.

  According to the invention of claim 2, in the invention of claim 1, instead of the cooling fan, a cooling fan having a cooling air direction opposite to the cooling air direction of each of the coolers and a dust stopper are provided. A third wind tunnel is provided, and the inlet surface of the third wind tunnel and the exhaust surface of the first wind tunnel are in positions where they do not affect each other's ventilation state.

  That is, in the forced air cooling type semiconductor cooling device attached under the floor of a railway vehicle, the first cooler according to claim 1, the second cooler according to claim 1, and these coolers are provided with a cooling airflow direction. Are arranged so as to be perpendicular to the vehicle floor and have no heat exchange with each other, and have a cooling air direction perpendicular to the vehicle floor, and a wind tunnel that collects the cooling air of the cooling fan in the cooler And a wind tunnel incorporating the cooling fan, and the wind tunnel is arranged so that the cooling air direction is perpendicular to the floor surface, and the air intake portion of the wind tunnel is from the air exhaust portion of the first cooler and the second cooler Is located below, and is provided with a dust stopper in the wind tunnel.

  Also, by distributing the cooling air from the cooling fan through the wind tunnel having the air conditioning guide, the semiconductor device is provided with a necessary air volume for suppressing the temperature rise of the semiconductor to the first cooler and the second cooler. Heat exchange. The cooling fan is built in a wind tunnel having a dust stopper, and the wind tunnel is arranged so that the cooling air direction is perpendicular to the floor surface, thereby improving the maintenance performance of the cooling fan.

  According to the forced air cooling type semiconductor cooling device of the present invention, it is possible to efficiently use the cooling air by the cooling fan, and it is possible to suppress the rise in the temperature of the semiconductor and to reduce the size and weight of the semiconductor cooling device.

(A) It is a perspective view which shows the semiconductor cooling device concerning 1st Embodiment of this application. (B) It is an upper view which shows the semiconductor cooling device concerning 1st Embodiment of this application. (A) It is a perspective view which shows the semiconductor cooling device concerning 2nd Embodiment of this application. (B) It is a front view which shows the semiconductor cooling device concerning 2nd Embodiment of this application. (A) It is a perspective view which shows the semiconductor cooling device using the cooler with a narrow width | variety with respect to the conventional cooling air direction. (B) It is an upper view which shows the semiconductor cooling device using the cooler with a narrow width | variety with respect to the conventional cooling wind direction. (A) It is a perspective view which shows the semiconductor cooling device (1) using the cooler wide with respect to the conventional cooling air direction. (B) It is a top view which shows the semiconductor cooling device (1) using the cooler wide with respect to the conventional cooling wind direction. (A) It is a perspective view which shows the semiconductor cooling device (2) using the cooler wide with respect to the conventional cooling air direction. (B) It is a top view which shows the semiconductor cooling device (2) using the cooler which is wide with respect to the conventional cooling wind direction.

  Embodiments of the present invention will be described below. FIG. 1A shows a perspective view of the semiconductor cooling device according to the first embodiment of the present invention, and FIG. 1B shows a top view of the semiconductor cooling device.

  As shown in FIG. 1, in the semiconductor cooling device of the present embodiment, the first cooler 4 and the second cooler 5 are arranged so that the cooling air directions are the same and there is no heat exchange with each other, and the first wind tunnel 1 is housed. And the 2nd wind tunnel 2 of the rectification wind tunnel which has the cooling fan 6 and the wind regulation guide 3 which have the cooling wind direction orthogonal to the cooling wind direction of a cooler is comprised. Here, a part of the surface forming the second wind tunnel 2 is not shown in order to squint the inside.

  Next, the operation of the present embodiment will be described. The semiconductor elements 7, 8, 9 of the inverter circuit are attached to the first cooler 4 having a wide cooling air width with respect to the cooling air flow length, and the semiconductor element 10 of the brake chopper circuit is attached to the second cooler 5. Cooling air from the cooling fan 6 having a cooling air direction perpendicular to the cooling air direction of the cooler is distributed to the first cooler 4 and the second cooler 5 through the second wind tunnel 2 having the air conditioning guide 3. Then, each semiconductor element is cooled.

  The thermal resistance and thermal time constant of the cooler (the time required for the temperature rise of the cooler to reach about 63.2% of the temperature rise with respect to the processing heat generation amount) have characteristics that are inversely proportional to the amount of cooling air. Since the semiconductor elements 7, 8, 9 of the inverter circuit that are operated during power running and braking have a large amount of heat generation, the thermal resistance of the cooler is lowered via the second wind tunnel 2 of the rectifying wind tunnel having the wind regulation guide 3. By distributing the cooling air volume to the first cooler 4 that cools the semiconductor elements 7, 8, 9 of the inverter circuit, the performance of the cooler can be improved, the temperature rise of the semiconductor element can be suppressed, and the cooler-shaped Suppression can also be achieved.

  Since the heat generation amount of the semiconductor element 10 of the brake chopper circuit that is operated at the time of regeneration invalidation is small, the thermal time constant of the second cooler 5 is increased through the second wind tunnel 2 of the rectifying wind tunnel having the wind guide 3. A semiconductor that depends on a thermal cycle due to a temperature change by distributing a cooling air amount to the second cooler 5 that cools the semiconductor element 10 of the brake chopper circuit so as to suppress a temperature change that is substantially inversely proportional to the thermal time constant. Can be extended.

  According to the above embodiment, the second wind tunnel 2 of the rectifying wind tunnel having the wind guide 3 can efficiently use the cooling air from the cooling fan 6 to improve the cooling performance and reduce the size and weight of the semiconductor cooling device. Is also effective.

  FIG. 2A is a perspective view of a semiconductor cooling device according to the second embodiment of the present invention, and FIG. 2B is a front view of the semiconductor cooling device according to the second embodiment of the present invention. Here, a part of the surface forming the second wind tunnel 2 is not shown in order to squint the inside.

  It is assumed that the semiconductor cooling device according to the first embodiment of the present invention is attached under the floor of a railway vehicle. As shown in FIG. 2, in the semiconductor cooling device of this embodiment, the first cooler 4 and the second cooler 5 have the same cooling air direction and are perpendicular to the vehicle floor and do not exchange heat with each other. Arranged in the first wind tunnel 1. A cooling fan 6 having a cooling air direction perpendicular to the vehicle floor, a second wind tunnel 2 that collects the cooling air from the cooling fan 6 in the cooler, and a third wind tunnel having the cooling fan 6 and a dust stopper 12. 11 is provided, and the third wind tunnel 11 is arranged such that the cooling air direction is perpendicular to the vehicle floor 13.

  Next, the operation of the present embodiment will be described. In the semiconductor cooling device installed under the floor of a railway vehicle, the operation and effect of the present embodiment are the same as those of the first embodiment, and the third wind tunnel 11 provided with a cooling fan 6 as a measure against dust intrusion is provided with a cooling wind direction. Is arranged perpendicular to the vehicle floor 13. The cooling fan 6 is provided so as to be separated from the ground, and the dust can be reduced by the gravity filter effect that falls due to its own weight. Further, the dust stopper 12 can reduce the clogging of the cooling fan 6 and maintainability of the cooling fan 6. There is an effect of improving.

  It goes without saying that the same effect can be obtained even if the wind tunnel or the like is arranged, for example, horizontally in addition to being vertical under the floor.

1: 1st wind tunnel 2: 2nd wind tunnel 3: Wind guide 4: 1st cooler 5: 2nd cooler 6: Cooling fan 7: Semiconductor element of an inverter circuit 8: Semiconductor element of an inverter circuit 9: Semiconductor element of inverter circuit 10: Semiconductor element of brake chopper circuit 11: Third wind tunnel 12: Dust stopper 13: Vehicle floor

Claims (2)

In a power converter attached to an underfloor device of a railway vehicle, a first cooler having a cooling air width wider than a cooling ventilation surface, and a second cooler having a cooling air width narrower than the first cooler, A cooling fan having a cooling air direction perpendicular to the cooling air direction, and a cooling fan for the cooling fan. A forced air cooling type semiconductor cooling apparatus comprising a second wind tunnel provided with a wind guide that distributes air to the first cooler and the second cooler. Instead of the cooling fan, a third wind tunnel including a cooling fan having a cooling air direction opposite to the cooling air direction of each of the coolers and a dust stopper is disposed, and the third wind tunnel is inserted. The forced air-cooling type semiconductor device according to claim 1, wherein the wind surface and the exhaust surface of the first wind tunnel are in positions where the mutual ventilation state is not affected.

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