JP2015156411A - Power converter and railway vehicle mounting the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently cool a power semiconductor of a power converter.

SOLUTION: A power converter includes: a heat receiving member; a plurality of power semiconductor elements having different calorific values; a plurality of heat pipes; and a plurality of fins attached to the heat pipes. The plurality of power semiconductor elements are provided on one surface of the heat receiving member; and the plurality of heat pipes are provided on the other surface of the heat receiving member. The plurality of heat pipes in the power converter with the heat radiating parts are constructed so that: the plurality of heat pipes consist of two types of heat pipes whose heat receiving part has a length different depending on its type; the heat receiving part is arranged so that its longitudinal direction is orthogonal to a flow direction of cooling air flowing through heat radiating members; a heat pipe whose heat receiving part has the short length is arranged inside a region obtained by projecting a power semiconductor element having a large calorific value on the heat receiving member; and a heat pipe whose heat receiving part has the long length is arranged across the inside and the outside of a region obtained by projecting a power semiconductor element having a small calorific value on the heat receiving member.

COPYRIGHT: (C)2015,JPO&INPIT

Description

The present invention relates to a power conversion device and a railway vehicle equipped with the same.

  The power conversion device is for controlling an electric motor that drives a vehicle such as an electric railway vehicle, and is installed under the floor of the vehicle. Since the space under the floor of the vehicle is limited, it is desired to reduce the size of the power conversion device. In the conventional power conversion device, the heat receiving part of the heat pipe is disposed so as to be in thermal contact with the heat receiving member as in Patent Document 1, and fins are arranged on the heat radiating part of the heat pipe to apply cooling air to the fins. In the structure for cooling the power semiconductor element, a structure in which the longitudinal direction of the heat receiving portion of the heat pipe is arranged in both directions parallel and perpendicular to the cooling air is known.

JP 2011-259536 A

  Particularly in power conversion devices such as high-speed vehicles, heating elements such as power semiconductors with high heat generation density tend to be closely arranged, and it is important how to cool the high heat generation to suppress the temperature rise of the semiconductor elements. is there. Further, in a three-level circuit inverter, converter, or the like, a semiconductor element having a large calorific value and a semiconductor element having a small calorific value are mixed, and it is required to cool a semiconductor element having a particularly large calorific value.

  In the conventional structure shown in Patent Document 1, since the number of heat pipes in the direction perpendicular to the flow of cooling air is small, sufficient heat is generated in the direction of cooling air flow when there is a large distribution in the amount of heat generated by the power semiconductor elements. There was a problem that the cooling effect could not be sufficiently obtained due to the inability to disperse.

  An object of the present invention is to provide a power conversion device capable of effectively cooling a power semiconductor element having a large calorific value even when heat generation of the power semiconductor element of the power conversion device is distributed.

  In order to achieve the above object, the power conversion device of the present invention has a heat receiving member, a plurality of power semiconductor elements, a plurality of heat pipes, and a plurality of heat radiating members attached to the heat pipe, The power semiconductor element is provided on one surface of the heat receiving member, the plurality of heat pipes are provided on the other surface of the heat receiving member, and at least a part of the plurality of heat pipes includes a heat radiating portion raised to the outside of the heat receiving member. In the power conversion device provided, the plurality of power semiconductor elements are composed of at least two types of power semiconductor elements having different calorific values, and the plurality of heat pipes have at least different lengths of the heat receiving portion that is embedded in the heat receiving member. It is composed of two types of heat pipes, and the heat receiving part is arranged so that the longitudinal direction is substantially perpendicular to the flow direction of the cooling air flowing through the heat radiating member. The heat pipe having a short length is arranged inside the projection region of the power semiconductor element having a large amount of heat generation onto the heat receiving member, and the heat pipe having a long heat receiving portion is to be a heat receiving member of the power semiconductor element having a small amount of heat generation. It was set as the structure arrange | positioned ranging over the inner side and the outer side of this projection area | region.

  According to the present invention, even when there is a distribution in the heat generation of the power semiconductor element, heat is concentrated on the fin side from the heat pipe with a short heat receiving portion and a relatively low heat generation amount for an element with a high heat generation amount. Heat is transferred from the element with a large amount of heat generation to the region of the heat receiving member with the element with a small amount of heat generation or the region without the element by providing a heat pipe with a long heat receiving part on the heat receiving member at a position where there is no element or element Therefore, the heat generated by the power semiconductor element is efficiently dispersed and the cooling performance is improved.

It is vertical direction sectional drawing parallel to the flow direction of the cooling wind of the power converter device in one Embodiment of this invention. It is the vertical direction sectional view seen from the direction perpendicular to the flow direction of the cooling wind of the power converter in one embodiment of the present invention. It is a figure which shows arrangement | positioning of the heat pipe and semiconductor element of the power converter device in one Embodiment of this invention. It is a figure which shows arrangement | positioning of the power semiconductor element of the power converter device in one Embodiment of this invention. It is a figure which shows arrangement | positioning of the heat pipe and semiconductor element in an example of the conventional power converter device. It is a figure which shows the numerical simulation result of the cooling performance of the power converter device of the structure of FIG. 5 and the structure (FIG. 3) in one Embodiment of this invention. It is a figure which shows the structure which mounted the power converter device of this invention in the rail vehicle.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 7 shows a configuration when the power conversion device according to the embodiment of the present invention is mounted on a railway vehicle. The power conversion device of the present invention is provided under the floor of a railway vehicle, etc., by converting the AC power of the overhead wire to DC by a converter, and further by controlling the frequency of power supplied to the electric motor that drives the vehicle by an inverter, etc. Control the rotation speed of the motor. In FIG. 7, the power conversion apparatus 1000 is fixed to the vehicle body 1002. An arrow 30 indicates the flow of cooling air. The cooling air is sucked from the suction grille 41 by the blower 40 and supplied to the cooling device 1001 of the power conversion device 1000.

  FIG. 1 is a vertical sectional view of the power conversion device according to the present embodiment (first embodiment) viewed from a direction parallel to the flow direction of the cooling air, and FIG. 2 is viewed from a direction perpendicular to the flow direction of the cooling air. A vertical sectional view is shown. 1 and 2, a so-called power semiconductor module (hereinafter also referred to as a power semiconductor module) including a plurality of power semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors) on one side of a heat receiving member 5 made of a metal such as an aluminum alloy. 70, 71, 72, 73, etc. are provided. In FIG. 1, reference numeral 1000 denotes an entire power converter, and 1001 denotes a cooling device for the power converter. The cooling device includes a heat receiving member 5, heat pipes 1, 2, 3, 4, a radiation fin 6, and the like. The power semiconductor elements 70, 71, 72, 73 and the like are fixed to the heat receiving member 5 and screws or the like (not shown) via members (not shown) such as grease. Electronic components 10 such as an IGBT drive circuit and a filter capacitor are installed on the power receiving element 5 side of the power semiconductor element. The periphery of the power semiconductor element mounted on the heat receiving member 5 is sealed with cases 11, 12, and 13. A heat receiving portion 101 of a U-shaped heat pipe 1 is embedded on the opposite side of the heat receiving member 5 from the power semiconductor element installation surface, and the heat receiving portion 101 is thermally connected to the heat receiving member 5 by soldering or the like. From both sides of the heat receiving part 101 of the U-shaped heat pipe 1, the heat radiating part 102 stands up. A plurality of fins 6 made of a metal such as aluminum or copper are connected to the heat radiating portion 102 by press fitting or the like. The U-shaped heat pipe is used by combining pipes having different shapes with different lengths of the heat receiving part and the heat radiating part.

  The arrangement of the heat receiving member 5, the heat pipe, and the power semiconductor element is shown in FIG. Further, the arrangement of the power semiconductor elements on the heat receiving member 5 is shown in FIG. 3 and 4, reference numerals 70, 71, 72, 73, 80, 81, 82, 83, 90, 91, 92, and 93 denote power semiconductor elements. The power semiconductor element is installed on the surface opposite to the heat pipe, and is indicated by a broken line in FIG. Although the heat receiving part of the heat pipe is also embedded in the heat block, it is indicated by a solid line for easy viewing of the drawing. The arrangement of these elements will be described using a three-level circuit converter as an example. The power semiconductor elements 70, 71, 72, 73 are IGBT modules including a plurality of IGBT (Insulated Gate Bipolar Transistor) elements, free wheel diodes, and the like. The power semiconductor elements 80, 81, 82 and 83 are constituted by clamp diode modules, and the power semiconductor elements 90, 91, 92 and 93 are constituted by IGBT modules. Depending on the operating conditions (power running operation, regenerative operation, etc.), the heat generation amount of the IGBT modules 70, 71, 72, 73 may be large and the heat generation amount of the IGBT modules 90, 91, 92, 93 may be large, the clamp diode module 80, The calorific values of 81, 82 and 83 are relatively small.

  As shown in FIGS. 1 to 3, the heat receiving portions 101 and 301 of the heat pipes 1 and 3 are set to be shorter than the heat receiving portions 201 and 401 of the heat pipes 2 and 4. Further, the heat radiating portions 102 and 202 of the heat pipes 1 and 2 are set longer than the heat radiating portions 302 and 402 of the heat pipes 3 and 4. The heat receiving portions 101 and 301 of the heat pipes 1 and 3 are set to a length that enters the inside of the portion where the power semiconductor element 90 is projected onto the heat receiving member 5. The heat pipes 2 and 4 having a long heat receiving portion are arranged side by side in the middle of the heat pipes 1 and 3 having a short heat receiving portion.

  A duct 14 is provided around the cooling device 1001, and cooling air is sent to the duct 14 by the blower 40 as shown in FIG. 7. In the present embodiment, the structure for forcibly blowing the cooling air with the cooling fan will be described. However, the structure for cooling the power conversion device by the traveling air generated when the vehicle travels, and the heated air rises. The present invention can also be applied to a structure that cools the power converter using natural convection. In the case of a structure using traveling air, the cooling air is substantially in the same direction as the traveling direction, so the longitudinal direction of the heat receiving portions of the heat pipes 1 and 2 is arranged in a direction perpendicular to the traveling direction of the vehicle. In the structure using natural convection, the longitudinal direction of the heat receiving portions of the heat pipes 1 and 2 is arranged in a direction perpendicular to the vertical direction (gravity direction) of the railway vehicle, that is, in a substantially horizontal direction.

  Next, the operation of cooling each power semiconductor element will be described taking the power semiconductor element 90 as an example. In FIG. 2, heat generated by the operation of a power semiconductor or the like provided inside the power semiconductor element 90 is transmitted to the heat receiving member 5 by heat conduction and reaches the heat receiving portion 101 of the heat pipe 1. A refrigerant (pure water or the like) is sealed in the heat pipe 1. The refrigerant heated in the heat receiving unit 101 evaporates into a gas and moves to the heat radiating unit 102. The refrigerant cooled by the air in the heat radiating unit 102 is condensed and returned to the liquid. The refrigerant condensed in the heat radiating unit 102 returns to the heat receiving unit 101 by gravity. Thus, by repeating evaporation and condensation and moving the refrigerant, the heat of the heat receiving member 5 is dissipated outside the power conversion device such as the atmosphere. The heat pipes 2, 3, and 4 are also filled with a refrigerant. Similarly, when the refrigerant moves by repeatedly evaporating and condensing, the heat of the heat receiving member 5 is dissipated outside the power converter such as the atmosphere.

  When the amount of heat generated by the power semiconductor elements 80, 81, 82, 83 is smaller than that of the power semiconductor elements 70, 71, 72, 73 and the power semiconductor elements 90, 91, 92, 93, the heat pipes 1, 3 having a short heat receiving portion. In this case, the number of the heat dissipating parts 102 and 302 is increased to dissipate heat to the fin side, and the heat pipes 2 and 4 having a long heat receiving part are used to generate heat in the vicinity of the element that generates a large amount of heat from the heat receiving member 5. By moving to a region or a region where no element exists, an element with a large amount of heat generation can be effectively cooled.

  The heat pipes 3 and 4 having a short heat radiating portion are relatively difficult to freeze even when the outside air temperature is a low temperature below freezing. Therefore, in addition to the heat pipes 1 and 2, a heat pipe 3 having a short heat receiving portion and a short heat radiating portion and a heat pipe 4 having a long heat receiving portion and a short heat radiating portion are provided, so that the heat receiving portion even when the outside air is at a low temperature. A heat pipe 3 that has a short heat dissipation part and a short heat pipe 3 ensures heat dissipation from the power semiconductor element that generates a large amount of heat to the fin side, and a heat pipe 4 that has a long heat receiving part and a short heat dissipating part causes a large amount of heat generated by the heat receiving member 5 By moving the heat in the vicinity of the element to a region where an element with a small amount of heat generation is present or a region where no element exists, an element with a large amount of heat generation can be effectively cooled.

  In addition, by disposing at least one heat pipe (for example, heat pipes 3 and 4 in this embodiment) with a short heat radiating portion with respect to the region of the heat receiving member to be projected of one power semiconductor element, a specific heat pipe is provided. It is possible to prevent the temperature of the semiconductor chip from rising without any operation of the element heat pipe. In particular, in order to balance the cooling performance when the outside air is at a high temperature and a low temperature, the ratio of the heat pipe having a short heat radiating portion to the total heat pipe is 20% to 60% in the region of the heat receiving member projected by one element. A range of is desirable.

  In this way, by arranging the heat pipes having different heat receiving portion lengths based on the heat generation amount of the element to be cooled and the arrangement of the elements, even when there is a distribution in the heat generation amount of the element, It can be cooled efficiently. Furthermore, in the heat pipe including the heat receiving portions having different lengths, by setting the heat radiating portions to different lengths, the effect of ensuring the cooling performance during cold weather can be further obtained. In addition, since the temperature of the cooling air becomes higher due to heat exchange with the heat radiating portion in the upstream area in the downstream area, the number of the radiating fins 6 that are heat radiating members is set as shown in FIG. By increasing the number of sheets in the flowing downstream region, the cooling performance of the power semiconductor element in the downstream region can be further maintained.

  As shown in FIG. 5, the temperature distribution on the element mounting surface of the heat receiving member in the case where three heat pipes having substantially the same length of the heat receiving portion are arranged and in the case of the heat pipe arrangement of the present embodiment shown in FIG. The result of the numerical simulation compared is shown in FIG.

  In FIG. 6, the temperature difference between the maximum temperature of the heat receiving member and the inlet air temperature in the arrangement of FIG. As can be seen from FIG. 6, the temperature difference between the heat receiving member and the inlet air can be reduced by 7% in the configuration of the heat pipe of the present embodiment in FIG. 2 than in the configuration in FIG. 5. However, FIG. 5 shows a case where the heat receiving portions of the heat pipes 1 and 3 and the heat pipes 2 and 4 in FIG. 3 are substantially equal, and the length of the heat radiating portion is set as described below. The effect of providing the different heat pipes 2 and 4 is obtained, and is not excluded from the present invention.

  3 is connected to the beam 15 in FIG. 1 to hold the duct 14. The beam 15 fixes the support column 16 and also plays a role of suppressing the passage of cooling air that bypasses the upper portion of the radiating fin 6 that is a radiating member. In the case where the length of the heat pipe entering the part with the support column 16 is too short, as shown in FIG. 3, the heat pipe 17 at the support column part may have a longer heat receiving part.

  If the heat pipe 17 disposed between the columns or between the columns and the end of the heat receiving member is adjusted to a length corresponding to the position of the columns, the cooling performance is improved, while the heat pipe 1 Since it can manufacture without increasing the kind of heat pipe if it comprises in any one of ~ 4, there exists an effect which manufacturing cost becomes cheap.

  As described above, according to the present embodiment, the longitudinal direction of the heat receiving portion of the heat pipe is arranged in a direction substantially perpendicular to the flow direction of the cooling air, and the portion embedded in the heat receiving member of the heat receiving portion has a large calorific value. A heat pipe that has a short heat receiving part that enters the projection region of the heat receiving member of the element, and a heat receiving part that has a relatively long heat straddling the portion of the heat receiving member of the power semiconductor element in which the heat receiving part has a relatively small amount of heat generation and the power semiconductor does not exist By arranging the heat pipe, even if there is a distribution of heat generation in the power semiconductor element, heat is concentrated on the fin side from the heat pipe of the heat receiving part with a short heat receiving part for elements with a large heat generation amount. In addition, a heat pipe having a long heat receiving portion is provided on a heat receiving member at a position where there is no element or a element with a relatively small heat generation amount, so It is possible to transfer heat into a small portion of the amount, heat generation of the power semiconductor element is efficiently dispersed to improve cooling performance.

DESCRIPTION OF SYMBOLS 1 ... U-shaped heat pipe 2 with short heat receiving part and long heat radiating part ... U-shaped heat pipe 3 with long heat receiving part and long heat radiating part ... U-shaped heat pipe 4 with short heat receiving part and short heat radiating part ... U-shaped heat pipe 5 having a long heat receiving portion and a short heat radiating portion ... Heat receiving member 6 ... Fin 10 ... Electrical components 11, 12, 13 ... Case 14 ... Duct 17 ... Heat pipe 40 in the column portion ... Blowers 70-73, 80 -83, 90-93 ... Power semiconductor element

Claims (6)

A heat receiving member, a plurality of power semiconductor elements, a plurality of heat pipes, and a plurality of heat dissipating members attached to the heat pipe,
The plurality of power semiconductor elements are provided on one surface of the heat receiving member,
The plurality of heat pipes are provided on the other surface of the heat receiving member,
In the power conversion device including a heat radiating portion raised at the outside of the heat receiving member, at least a part of the plurality of heat pipes,
The plurality of power semiconductor elements are composed of at least two types of power semiconductor elements having different calorific values,
The plurality of heat pipes are composed of at least two types of heat pipes having different lengths of a heat receiving portion which is a portion embedded in the heat receiving member,
The heat receiving portion is disposed so that the longitudinal direction is substantially perpendicular to the flow direction of the cooling air flowing through the heat radiating member,
The heat pipe having a short length of the heat receiving portion is disposed inside a projection region on the heat receiving member of the power semiconductor element having a large calorific value,
The heat conversion apparatus according to claim 1, wherein the heat pipe having a long heat receiving portion is disposed across an inner side and an outer side of a projection region onto the heat receiving member of the power semiconductor element having a small heat generation amount. The power conversion device according to claim 1,
The plurality of heat pipes are composed of heat pipes having different lengths of the heat radiation part.
The power converter characterized by the above-mentioned. The power conversion device according to claim 2,
At least one heat pipe having a short heat radiating portion is disposed in a projection region of each of the plurality of power semiconductor elements onto the heat receiving member. In the power converter device in any one of Claims 1 thru | or 3,
The power conversion device comprising a larger number of the heat radiating members on the downstream side than the upstream side on which the cooling air flows. In the power converter device in any one of Claims 1 thru | or 4,
A duct that covers a space through which the cooling air flows and is provided outside the heat pipe;
Between the duct and the heat receiving member, a plurality of pillars holding the duct;
It has a heat pipe provided with the heat receiving part based on the length between the said support | pillars or between the said support | pillar and the edge part of the said heat receiving member. The power converter device characterized by the above-mentioned.   A railway vehicle equipped with the power conversion device according to any one of claims 1 to 5.