JP2013215080A - Electric power conversion apparatus and work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably form narrow parallel passages.SOLUTION: Power modules 50A to 50C, 51 are mounted on a cold plate 10, and multiple parallel passages 17 for flowing a cooling medium are formed in a mounting region that overlaps with the power modules 50A to 50C, 51. The cold plate 10 is divided into a first cooling member 40 and a second cooling member 42. The first cooling member 40 includes: a first plane P1 where the power modules 50A to 50C, 51 are mounted; a second plane P2 that is a rear plane of the first plane P1. The second cooling member 42 has a third plane P3 closely contacting with the second plane P2 of the first cooling member 40. Multiple grooves 44, 46 forming the multiple parallel passages 17 are formed in at least one of the second plane P2 of the first cooling member 40 and the third plane P3 of the second cooling member 42.

Description

  The present invention relates to a power conversion device and a work machine including a power module and a cooling mechanism.

  A hybrid construction machine is equipped with a power module such as an inverter for controlling an electric motor and a boost converter. The power module is cooled by thermally coupling one cooling channel bent in a U shape to the power module. A structure using a plurality of parallel flow paths for flowing a cooling medium in the same direction is also known.

JP 2010-226781 A JP 2007-12722 A JP 2008-294069 A

  Generally, a heat sink is often made of a metal material such as aluminum by a sand casting method. When the diameter of the parallel flow path is as large as about 5 mm to 10 mm, the parallel flow path can be formed by arranging the core in a portion corresponding to the parallel flow path. However, when a thin parallel flow path of 5 mm or less, for example, about 2 to 3 mm is required, the formation by the core decreases the yield and increases the cost. For this reason, it is not suitable for mass production.

  One embodiment of the present invention relates to a power converter. The power conversion device includes a power module, and a cold plate in which a plurality of parallel flow paths for flowing a cooling medium are formed in a mounting region where the power module is mounted and overlaps with the power module. The cold plate is divided into a first cooling member and a second cooling member. The first cooling member has a first plane on which the power module is mounted and a second plane that is the back surface of the first plane. The second cooling member has a third plane that is in intimate contact with the second plane of the first cooling member. A plurality of grooves forming a plurality of parallel flow paths are formed in at least one of the second plane of the first cooling member and the third plane of the second cooling member.

  According to an aspect of the present invention, narrow parallel flow paths can be formed stably.

FIG. 1A is a perspective view of the power conversion device according to the first embodiment, and FIG. 1B is a plan sectional view of a cold plate used in the electrode conversion device according to the embodiment. 2A and 2B are cross-sectional views taken along one-dot chain lines 2A-2A and 2B-2B in FIG. 1B, respectively. It is a graph which shows the simulation result of the relationship between the total flow volume of the input side flow path of the power converter device by Example 1, and the flow volume of a parallel flow path group. It is a partial top view of the cooling flow path of the power converter device by Example 2. 5A and 5B are cross-sectional views of the power conversion device according to the third embodiment and its modification, respectively. It is sectional drawing in the dashed-dotted line 6-6 of FIG. 1B of the cold plate which concerns on Example 4. FIG. It is the perspective view which looked at the 1st cooling member of Drawing 6 from the 2nd plane side. It is the perspective view which looked at the 2nd cooling member of Drawing 6 from the 3rd plane side. 9A to 9C are cross-sectional views of a cold plate according to a modification of the fourth embodiment. FIG. 9 is a cross-sectional view of a cold plate according to a fifth embodiment. It is the perspective view which looked at the 2nd cooling member of Drawing 10 from the 2nd plane side. FIG. 12 is a plan view of an excavator according to the sixth embodiment. FIG. 13 is a partially broken side view of the shovel according to the sixth embodiment. FIG. 14 is a block diagram of an excavator according to the sixth embodiment. FIG. 15 is a partially broken side view of the forklift according to the seventh embodiment.

[Example 1]
FIG. 1A is a perspective view of the power converter according to the first embodiment. Power modules 50 </ b> A to 50 </ b> C and 51 are mounted on the cold plate 10. The power modules 50A to 50C and 51 are thermally coupled to the cold plate 10 to cool the power modules 50A to 50C and 51. The power modules 50A to 50C are, for example, U-phase, V-phase, and W-phase inverter circuits for driving an embedded magnet (IPM) motor. The power module 51 is, for example, a boost converter for charging / discharging the power storage module. The power modules 50A to 50C, 51 include a power semiconductor element such as an insulated gate bipolar transistor (IGBT), a driving circuit thereof, a self-protection circuit, and the like.

  FIG. 1B shows a plan sectional view of the cold plate 10. A flow path for flowing a cooling medium is formed inside the cold plate 10. Hereinafter, the configuration of the flow path will be described. In FIG. 1B, an xy orthogonal coordinate system is defined in which the right direction is the positive direction of the x axis and the upward direction is the positive direction of the y axis.

  A cooling medium inflow port 11 and a discharge port 21 are provided at the edge on the negative side in the x-axis direction of the cold plate 10. From the inflow port 11, a runway 12, a tapered channel 13, and an inlet channel 14 are formed in this order in the positive direction of the x axis. The width of the approach path 12 and the inlet-side channel 14 is constant, and the width of the inlet-side channel 14 is wider than the width of the approach path 12. The width of the tapered channel 13 gradually increases from the runway 12 toward the inlet channel 14. The cooling medium that has flowed into the runway 12 from the inflow port 11 flows into the inlet-side flow path 14 via the tapered flow path 13. The inlet channel 14 has a planar shape that is long in the x-axis direction, and allows the cooling medium to flow in the positive direction of the x-axis.

  A plurality of parallel flow paths 17 that are long in the y-axis direction are arranged in the x-axis direction. The upstream end of the parallel flow path 17 is connected to the input side flow path 14 via the input side equalization structure 22. The cooling medium flowing in the inlet-side channel 14 flows into each of the parallel channels 17 via the inlet-side equalization structure 22. Each of the parallel flow paths 17 causes the cooling medium flowing in from the input flow path 14 to flow in the negative y-axis direction.

  Each downstream end of the parallel flow path 17 is connected to the output side flow path 20 via the output side equalization structure 23. The cooling medium flowing through the parallel flow path 17 flows into the output side flow path 20 via the output side equalizing structure 23.

  The outlet-side channel 20 has a planar shape that is long in the x-axis direction, and the end on the negative side in the x-axis direction becomes the discharge port 21. The cooling medium that has flowed into the outlet-side channel 20 from the parallel channel 17 flows in the negative direction of the x axis, and is discharged from the discharge port 21 to the outside of the cold plate 10.

  The entry-side equalization structure 22 includes an entry-side buffer chamber 15 and a plurality of entry-side circulation holes 16. The entry-side buffer chamber 15 has a planar shape that is long in the x-axis direction, and is disposed on the side of the entry-side passage 14 in parallel with the entry-side passage 14. The upstream end of the parallel flow path 17 is connected to the entry-side buffer chamber 15. That is, the upstream ends of the parallel flow paths 17 are connected to each other by the entrance buffer chamber 15.

  The inlet-side circulation holes 16 are discretely distributed in the x-axis direction and connect the inlet-side flow path 14 and the inlet-side buffer chamber 15. The flow path cross section of the inlet side circulation hole 16 arranged on the downstream side of the inlet side flow path 14 is larger than the flow path cross section of the inlet side circulation hole 16 arranged on the upstream side. Specifically, the dimension in the x-axis direction is made larger as the inlet-side circulation hole 16 located on the positive side of the x-axis.

  The exit side equalizing structure 23 includes an exit side buffer chamber 18 and a plurality of exit side circulation holes 19. This shape is symmetrical with the shape of the entrance-side equalization structure 22 with respect to a virtual straight line connecting the midpoints of the parallel flow paths 17.

  The cross sections of the inlet side flow path 14, the inlet side buffer chamber 15, the inlet side flow hole 16, the outlet side flow path 20, the outlet side buffer chamber 18, and the outlet side flow hole 19 are rectangular. The channel cross section is circular.

  The power modules 50 </ b> A, 50 </ b> B, 50 </ b> C, 51 are arranged so as to overlap the four parallel flow paths 17, respectively. The power modules 50 </ b> A, 50 </ b> B, 50 </ b> C, 51 are thermally coupled to the parallel flow path 17. The power modules 50A, 50B, 50C, and 51 can be efficiently cooled by the cooling medium flowing through the parallel flow path 17.

  Next, an example of the dimension of the planar shape of these flow paths will be described. The width W1 of the inlet side channel 14 and the outlet side channel 20 is 40 mm. The distance G between the inlet-side channel 14 and the inlet-side buffer chamber 15 and the interval G between the outlet-side channel 20 and the outlet-side buffer chamber 18 are 5 mm. The dimension W2 of the entrance buffer chamber 15 and the exit buffer chamber 18 in the y direction is 20 mm. Each parallel flow path 17 has a length L1 of 70 mm. The center-to-center distance L2 between the parallel flow paths 17 adjacent to each other is 17.75 mm. The dimensions S1, S2, S3, and S4 in the x-axis direction of the first, second, third, and fourth inlet-side flow holes 16 counted from the upstream side of the inlet-side flow path 14 are 39 mm, 43 mm, and 54 mm, respectively. 65 mm.

  2A is a cross-sectional view taken along one-dot chain line 2A-2A in FIG. 1B. In the cold plate 10, an inlet buffer chamber 15, a parallel channel 17, and an outlet channel 20 are formed. The cold plate 10 has a thickness H1 of 25 mm. The height (dimension in the thickness direction of the cold plate 10) H2 of the inlet side buffer chamber 15 and the outlet side flow path 20 is 15 mm. Each parallel passage 17 has a diameter D of 3 mm. The heights of the inlet-side flow path 14, the inlet-side circulation hole 16, the outlet-side buffer chamber 18, and the outlet-side circulation hole 19 are the same as the height H <b> 2 of the inlet-side buffer chamber 15.

  2B is a cross-sectional view taken along one-dot chain line 2B-2B in FIG. 1B. In the cold plate 10, an inlet-side channel 14, an inlet-side buffer chamber 15, a parallel channel 17, an outlet-side buffer chamber 18, and an outlet-side channel 20 are formed. The inlet side circulation hole 16 and the outlet side circulation hole 19 (FIG. 1B) do not appear in this cross-sectional view.

  The above-mentioned cold plate 10 can be produced by a casting method, for example. For the cold plate 10, for example, aluminum can be used.

  Next, the effect of adopting the configuration of the cooling flow path of the power conversion device according to the first embodiment will be described. When a plurality of parallel flow paths 17 are directly connected to the inlet-side flow path 14, the flow rate of the parallel flow paths 17 arranged on the downstream side is relatively reduced. On the other hand, in the first embodiment, the parallel flow path 17 is connected to the input side flow path 14 via the input side equalization structure 22.

  The flow passage cross-sectional area of the inlet-side flow hole 16 located on the downstream side of the inlet-side flow path 14 is larger than the flow passage cross-sectional area of the inlet-side flow hole 16 located on the upstream side. For this reason, the pressure distribution in the x-axis direction in the entrance buffer chamber 15 approaches uniformly. Thereby, the flow volume of the some parallel flow path 17 approaches uniformly. As a result, the four power modules 50A to 50C and 51 can be evenly cooled.

  A plurality of parallel flow paths 17 overlapping with one power module can be considered as one parallel flow path group. For example, four parallel flow paths 17 that overlap the power module 50A overlap the first parallel flow path group, and four parallel flow paths 17 that overlap the power module 50B overlap the second parallel flow path group and the power module 50C. The three parallel flow paths 17 can be considered as a third parallel flow path group, and the four parallel flow paths 17 overlapping the power module 51 can be considered as a fourth parallel flow path group. In this case, the parallel flow path group may be disposed corresponding to the position where the power module is to be disposed. Since the flow rates of the plurality of parallel flow paths 17 approach uniformly, variation in cooling capacity for each parallel flow path group is reduced.

  Next, the effect of providing the entry side buffer chamber 15 will be described. It can be considered that the flow rate can be made uniform also by directly connecting the parallel flow path 17 to the inlet flow path 14 and adjusting the opening area of the connecting portion. However, in this structure, fluctuations in the overall flow rate (flow rate of the cooling medium flowing through the inlet-side flow path 14) affect the effect of equalizing the flow rate. If the overall flow rate is within a certain range, a sufficient leveling effect can be obtained. However, if the overall flow rate is out of the range, a sufficient leveling effect is not always obtained.

  FIG. 3 shows a simulation result of the relationship between the overall flow rate flowing through the inlet-side flow path 14 and the flow rate flowing through the parallel flow path 17 of the power conversion device according to the first embodiment. The four parallel flow paths 17 corresponding to each of the power modules 50A to 50C and 51 were combined into one parallel flow path group, and the flow rate was calculated for each parallel flow path group. The flow path groups A, B, C, and D shown in FIG. 3 correspond to the power modules 50A to 50C and 51, respectively.

  The horizontal axis in FIG. 3 represents the total flow rate in the unit “L / min”, and the vertical axis represents the flow rate in the parallel flow path group in the unit “L / min”. As the overall flow rate increases, the flow rate of each flow path group also increases. Even if the total flow rate fluctuates, the flow rate of each flow path group maintains about 25% of the total flow rate. Thus, even if the overall flow rate fluctuates, a sufficient effect of equalizing the flow rate of the parallel flow path 17 is obtained. This is because the entrance buffer chamber 15 is provided.

  As described above, the entry-side buffer chamber 15 has an effect of suppressing a decrease in the uniformizing effect due to a change in the entire flow rate of the cooling medium. Furthermore, by arranging the entry side buffer chamber 15, it is possible to reduce the homogenization effect due to the deviation between the optimal dimensions of each part and the design dimensions for equalizing the flow rate, the dimensional variation occurring in the manufacturing stage, and the like. Can be suppressed.

  By arranging an outlet side equalization structure 23 similar to the inlet side equalization structure 22 between the parallel flow path 17 and the outlet side flow path 20, the flow rate equalization effect between the parallel flow paths 17 is also achieved. Can be further enhanced. Note that the entry-side equalization structure 22 may be disposed only on the entry side, and the exit-side equalization structure 23 may be omitted. In this case, the downstream end of the parallel flow channel 17 is directly connected to the outlet flow channel 20.

In the first embodiment, four inlet-side circulation holes 16 are arranged, but other numbers may be used. Even if the number is other than four, the channel cross-sectional area of the inlet-side circulation hole 16 that is relatively located downstream of the inlet-side channel 14 is relatively positioned upstream of the inlet-side channel 14. The flow passage cross-sectional area of the inlet-side circulation hole 16 is made larger. Thereby, the flow volume of the parallel flow path 17 can be equalized.

In the first embodiment, four power modules 50A, 50B, 50C, and 51 are mounted on one cold plate 10, but the number of power modules to be mounted may be a plurality other than four. Further, when a plurality of heat sources are included in one power module, one power module may be mounted on one cold plate 10. When the heat sources are arranged in a line in the power module, the power module may be fixed to the cold plate 10 so that the heat sources are arranged in the x direction of FIG. 1B.
[Example 2]
FIG. 4 is a partial plan view of the flow path of the power conversion device according to the second embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1B will be described, and description of the same configuration will be omitted.

  In Example 1, the wall surfaces on both sides of the inlet-side circulation hole 16 (FIG. 1B) were substantially flat. In the second embodiment, the wall surfaces on both sides of the inlet-side circulation hole 16 are curved column surfaces. At the connecting portion between the inlet-side circulation hole 16 and the inlet-side channel 14 and at the connecting portion between the inlet-side circulation hole 16 and the inlet-side buffer chamber 15, the channel sectional area is maximum, and the channel sectional area is at the center portion. Is the smallest. That is, the channel cross-sectional area of the inlet-side circulation hole 16 gradually decreases from the inlet-side channel 14 toward the inlet-side buffer chamber 15, and gradually increases after the intermediate point.

  Generation of turbulent flow can be suppressed by making the wall surfaces on both sides of the inlet-side circulation hole 16 into curved surfaces as described above. Thereby, pressure loss can be reduced. The outlet-side circulation hole 19 (FIG. 1A) may have the same shape as the inlet-side circulation hole 16 of the second embodiment.

  Furthermore, the upstream end of the parallel flow path 17 is tapered so that the cross-sectional area of the flow path gradually increases toward the end. By adopting such a shape, the pressure loss can be reduced even at the upstream end of the parallel flow path 17. Note that the downstream end of the parallel flow path 17 may also be tapered like the upstream end.

[Example 3]
FIG. 5A shows a cross-sectional view of the power converter according to the third embodiment. The configurations of the cold plate 10 and the power modules 50 </ b> A to 50 </ b> C and 51 are the same as those of the first or second embodiment. In the third embodiment, the cold plate 10 and the power modules 50 </ b> A to 50 </ b> C and 51 are accommodated in the housing 30. The housing 30 includes a housing lower portion 30A having a bottom surface and a side surface rising from an outer peripheral portion of the bottom surface, and an upper lid 30B that closes an opening of the housing lower portion 30A. The cold plate 10 is fixed to the bottom surface of the housing lower part 30A.

  FIG. 5B shows a cross-sectional view of a power conversion device according to a modification of the third embodiment. In this modification, a cooling flow path is formed in the bottom surface of the housing lower part 30A. That is, the bottom surface of the housing lower part 30 </ b> A also serves as the cold plate 10. With this configuration, the number of parts can be reduced.

  Furthermore, according to the power converter of FIG. 5B, since there is no possibility that the cooling medium enters the inside of the housing, the reliability of the power converter can be improved.

[Example 4]
In order to efficiently cool the power modules 50A to 50C, 51, it is effective to reduce the diameter of the parallel flow path 17 of the cold plate 10 as much as possible and to increase the number thereof as much as possible. On the other hand, when the cold plate 10 is integrally formed by a casting method, if the thin parallel flow passage 17 having a diameter of about 2 to 3 mm is stably formed, the yield decreases and the cost increases. Therefore, in the fourth embodiment, the structure of the cold plate 10 in which the narrow parallel flow path 17 can be formed will be described.

  A plan sectional view of the cold plate 10 according to the fourth embodiment is the same as that of FIG. 1B. 6 shows a cross-sectional view of the cold plate 10 taken along the alternate long and short dash line 6-6 in FIG. 1B. The cold plate 10 is formed by being divided into a first cooling member 40 and a second cooling member 42, which are independently produced by a casting method.

  In the fourth embodiment, as in FIG. 5B, a case where the bottom surface of the housing lower part 30A also serves as the cold plate 10 will be described. In addition, this invention is not limited to it, As shown to FIG. 5A, the cold plate 10 may be fixed to the bottom face of the housing | casing lower part 30A.

  As already described, the power modules 50 </ b> A to 50 </ b> C and 51 are mounted on the cold plate 10. A plurality of parallel flow paths 17 for flowing the cooling medium are formed in a mounting region overlapping the power modules 50A to 50C of the cold plate 10.

  The first cooling member 40 has a first plane P1 on which the power modules 50A to 50C and 51 are mounted. Moreover, the 1st cooling member 40 is the back surface of the 1st plane P1, and has the 2nd plane P2 which overlaps with a mounting area | region.

  The second cooling member 42 has a third plane P3 in close contact with the second plane P2 of the first cooling member 40 that overlaps the mounting region.

  In the second plane P2 of the first cooling member 40, a plurality of grooves 44 that extend in the y-axis direction and are parallel to each other are formed. Similarly, in the third plane P3 of the second cooling member 42, a plurality of grooves 46 that extend in the y-axis direction and are parallel to each other are formed. The cross sections of the grooves 44 and 46 are semicircular, and the plurality of grooves 44 and the plurality of grooves 46 are formed at positions corresponding to each other. One groove 44 and a corresponding groove 46 are parallel to each other when the second plane P2 of the first cooling member 40 and the third plane P3 of the second cooling member 42 are in close contact with each other. A flow path 17 is formed. The grooves 44 and 46 may be formed by casting using a sand mold, or may be formed by mechanical means such as polishing and excavation after the first cooling member 40 and the second cooling member 42 are cast. .

  FIG. 7 is a perspective view of the first cooling member 40 viewed from the second plane P2 side. In FIG. 7, the side wall of the housing lower part 30A is omitted. The first cooling member 40 includes a groove forming part 60 </ b> A, a side wall 62, an inlet side partition wall 64, a bottom surface 66 </ b> A, an outlet side partition wall 68, and a flow path forming part 69. The groove forming portion 60A, the side wall 62, the entry-side partition wall 64, and the exit-side partition wall 68 protrude from the bottom surface 66A in the negative z-axis direction.

  The groove forming portion 60A is a portion corresponding to the second plane P2, and a plurality of grooves 44 are formed in the y-axis direction. The diameter of the groove 44 is the thinnest and constant near the center of the parallel flow path 17 and is tapered so as to increase toward the upstream end of the parallel flow path 17 and toward the downstream end. The narrowest part of the groove 44 has a diameter of 5 mm or less, specifically about 2 to 3 mm.

  The plurality of entry-side partition walls 64 are opposed to the upstream end face P10 of the groove forming portion 60A in which the plurality of parallel flow paths 17 are formed with a predetermined interval W2. The plurality of inlet-side partition walls 64 are arranged in the vertical direction, that is, in the x-axis direction with the plurality of parallel flow channels 17 with an interval (the inlet-side circulation hole 16). A region surrounded by the plurality of inlet-side partition walls 64 and the upstream end face P10 of the groove forming portion 60A forms the inlet-side buffer chamber 15 that makes the flow rates of the plurality of parallel flow paths 17 close to uniform.

  The plurality of outlet-side partitions 68 are formed to protrude from the bottom surface 66A in the negative z-axis direction. Specifically, the plurality of outlet-side partition walls 68 are opposed to the upstream end surface P11 of the groove forming portion 60A where the plurality of parallel flow paths 17 are formed with a predetermined interval W2. The plurality of outlet-side partition walls 68 are arranged in the direction perpendicular to the plurality of parallel flow paths 17 (x-axis direction), that is, with the outlet-side circulation holes 19 therebetween. A region surrounded by the plurality of outlet partitions 68 and the downstream end face P11 of the groove forming portion 60A forms the outlet buffer chamber 18 that makes the flow rates of the plurality of parallel flow paths 17 close to uniform.

  The side wall 62 is provided along the outer periphery of the bottom surface 66A. A region surrounded by the side wall 62 and the plurality of inlet-side partition walls 64 forms the inlet-side flow path 14. Similarly, the region surrounded by the side wall 62 and the outlet side partition wall 68 forms the outlet side channel 20.

  In addition, the tapered flow path 13 described above is formed in the flow path forming portion 69.

  From the viewpoint of efficient cooling of the power module, it is desirable that the power module and the parallel flow path 17 be as close as possible. Therefore, in the present embodiment, the center of the plurality of grooves, in other words, the second plane P2 is located closer to the power module than 1/2 of the height H2 of the entrance buffer chamber 15 and the exit buffer chamber 18. That is, when the height of the groove forming portion 60A is H3, H3 <H2 / 2 is established.

  FIG. 8 is a perspective view of the second cooling member 42 as viewed from the third plane P3 side. A broken line portion 62 indicates a portion overlapping with the side wall 62 of FIG. In the broken line portion 62 and the third plane P3, the first cooling member 40 and the second cooling member 42 are closely fixed. The fixing means is not particularly limited, but general screwing may be used. Moreover, in order to improve airtightness, the 1st cooling member 40 and the 2nd cooling member 42 are fitted via the O-ring (not shown) provided in the broken line part 62. FIG.

The above is the configuration of the cold plate 10 according to the fourth embodiment.
According to the cold plate 10, the cold plate 10 is not integrally formed, but is divided into the first cooling member 40 and the second cooling member 42 and cast, so that the narrow parallel flow path 17 can be stably formed. Can do.

  9A to 9C are cross-sectional views of a cold plate according to a modification of the fourth embodiment. In FIG. 9A, a groove 44 having a substantially circular cross section is formed on the first cooling member 40 side, and the second cooling member 42 is flat. Conversely, a groove 44 having a substantially circular cross section may be formed in the second cooling member 42 to flatten the first cooling member 40.

  9B, the groove 44 and the groove 46 are V-shaped, and in FIG. 9C, the groove 44 and the groove 46 are U-shaped. 9B and 9C, the groove may be formed only in the groove 44 or only in the groove 46.

  In a modification of the fourth embodiment, at least one of the side wall 62, the entry-side partition wall 64, the exit-side partition wall 68, and the flow path forming unit 69 is integrally formed with the second cooling member 42 instead of the second cooling member 42. Also good. Thus, by forming a parallel flow path with a small cross-sectional area with respect to the inlet-side flow path, the heat conduction efficiency of the first cooling member 40 and the cooling medium can be increased, and the cooling effect of the power module is improved. be able to.

[Example 5]
FIG. 10 is a cross-sectional view of the cold plate according to the fifth embodiment. FIG. 11 is a perspective view of the second cooling member of FIG. 10 as viewed from the second plane side. In Example 5, the cross-sectional shape of the plurality of parallel flow channels 17 has a flat shape. The flat shape may be a rectangle as shown in FIG. 10, for example, or may be a substantially rectangle with rounded corners as shown in FIG. Specifically, a plurality of grooves 44 are formed on the second plane P2 of the first cooling member 40 so that the corresponding parallel flow path 17 has a flat cross section. You may provide the some groove | channel 44 in the location which overlaps with the power modules 50A-50C and 51 which are heat generating bodies, respectively.

  Each of the plurality of grooves 44 has a depth of about several hundred μm to 1 m and a width of about several mm to several cm, and has a larger aspect ratio that is a ratio of the width and depth of the cross-sectional shape than the fourth embodiment. Moreover, the cross-sectional area of the groove 44 is smaller than that of the inlet-side flow path. The groove 44 may be formed by casting or may be formed by cutting.

  Also in the fifth embodiment, the same effect as in the fourth embodiment can be obtained. In addition, in the fifth embodiment, since the wide and shallow groove 44 may be formed, there is an advantage that the processing is easier than in the fourth embodiment even when either casting or cutting is employed.

  10 and 11, the groove 44 is formed only on the first cooling member 40 side, but the groove 46 may be formed only on the second cooling member 42 side. A groove 44 may be formed in the cooling member 40 and a groove 46 may be formed in the second cooling member 42. Thus, by forming a parallel flow path having a small cross-sectional area with respect to the inlet-side flow path, the heat conduction efficiency of the first cooling member 40 and the cooling medium is increased, and as a result, while improving the cooling effect of the power module, Manufacturing cost can be reduced.

  In the fifth embodiment, the number of parallel flow paths 17 does not necessarily need to match the number of power modules 50A to 50C and 51. In this case, the plurality of parallel flow paths 17 may be provided at locations unrelated to the locations of the power modules 50A to 50C.

[Example 6]
FIG. 12 is a plan view of an excavator as an example of the work machine according to the sixth embodiment. An upper swing body 70 is attached to the lower traveling body 71 via a swing bearing 73. The upper swing body 70 includes an engine 74, a main pump 75, an electric motor 76 for rotation, an oil tank 77, a cooling fan 78, a seat 79, a power storage module 80, a motor generator 83, an inverter 90 for motor generator, and an inverter 91 for rotation. And a condenser converter 92 are mounted. The engine 74 generates power by burning fuel. The engine 74, the main pump 75, and the motor generator 83 transmit and receive torque to and from each other via the torque transmission mechanism 81. The main pump 75 supplies pressure oil to a hydraulic cylinder such as the boom 82.

  The motor generator 83 is driven by the power of the engine 74 to generate power (power generation operation). The generated power is supplied to the power storage module 80, and the power storage module 80 is charged. In addition, the motor generator 83 is driven by the electric power from the power storage module 80 and generates power for assisting the engine 74 (assist operation). The oil tank 77 stores oil of the hydraulic circuit. The cooling fan 78 suppresses an increase in the oil temperature of the hydraulic circuit. The operator sits on the seat 79 and operates the hybrid excavator.

  In FIG. 13, the partially broken side view of the shovel by Example 6 is shown. An upper swing body 70 is mounted on the lower traveling body 71 via a swing bearing 73. The upper swing body 70 includes a swing frame 70A, a cover 70B, and a cabin 70C. The swivel frame 70A functions as a support structure for the cabin 70C and various components. The cover 70B covers various components mounted on the support structure 70A, for example, the power storage module 80, the condenser converter 92, and the like. A seat 79 (FIG. 12) is accommodated in the cabin 70C.

  The turning electric motor 76 (FIG. 12) turns the turning frame 70 </ b> A to be driven clockwise or counterclockwise with respect to the lower traveling body 71. A boom 82 is attached to the upper swing body 70. The boom 82 swings up and down with respect to the upper swing body 70 by a hydraulically driven boom cylinder 107. An arm 85 is attached to the tip of the boom 82. The arm 85 swings in the front-rear direction with respect to the boom 82 by an arm cylinder 108 that is hydraulically driven. A bucket 86 is attached to the tip of the arm 85. The bucket 86 swings in the vertical direction with respect to the arm 85 by a hydraulically driven bucket cylinder 109.

  The power storage module 80 is mounted on the turning frame 70 </ b> A via a power storage module mount 95 and a damper (anti-vibration device) 96. The capacitor converter 92 is mounted on the turning frame 70 </ b> A via a converter mount 97 and a damper 98. Cover 70 </ b> B covers power storage module 80. The electric motor 76 for turning (FIG. 12) is driven by the electric power supplied from the power storage module 80. In addition, the turning electric motor 76 generates regenerative electric power by converting kinetic energy into electric energy. The power storage module 80 is charged by the generated regenerative power.

  In FIG. 14, the block diagram of the shovel by Example 6 is shown. In FIG. 14, the mechanical power system is represented by a double line, the high-pressure hydraulic line is represented by a thick solid line, and the pilot line is represented by a broken line.

  The drive shaft of the engine 74 is connected to the input shaft of the torque transmission mechanism 81. As the engine 74, an engine that generates a driving force by a fuel other than electricity, for example, an internal combustion engine such as a diesel engine is used. The engine 74 is always driven during operation of the work machine.

  The drive shaft of the motor generator 83 is connected to the other input shaft of the torque transmission mechanism 81. The motor generator 83 can perform both the electric (assist) operation and the power generation operation. As the motor generator 83, for example, an internal magnet embedded (IPM) motor in which magnets are embedded in the rotor is used.

  The torque transmission mechanism 81 has two input shafts and one output shaft. The output shaft is connected to the drive shaft of the main pump 75.

  When the load applied to the engine 74 is large, the motor generator 83 performs an assist operation, and the driving force of the motor generator 83 is transmitted to the main pump 75 via the torque transmission mechanism 81. Thereby, the load applied to the engine 74 is reduced. On the other hand, when the load applied to the engine 74 is small, the driving force of the engine 74 is transmitted to the motor generator 83 via the torque transmission mechanism 81, so that the motor generator 83 is in a power generation operation. When assisting the motor generator 83, three-phase AC power is supplied from the inverter 90 to the motor generator 83. When the motor generator 83 is in a power generation operation, three-phase AC power is supplied from the motor generator 83 to the inverter 90. The inverter 90 is controlled by the control device 130.

  The control device 130 includes a central processing unit (CPU) 130A and an internal memory 130B. The CPU 130A executes a drive control program stored in the internal memory 130B. The control device 130 alerts the driver by displaying the deterioration state of various devices on the display device 135.

  The main pump 75 supplies hydraulic pressure to the control valve 117 via the high pressure hydraulic line 116. The control valve 117 distributes hydraulic pressure to the hydraulic motors 101A and 101B, the boom cylinder 107, the arm cylinder 108, and the bucket cylinder 109 in accordance with a command from the driver. The hydraulic motors 101A and 101B drive the two left and right crawlers provided in the lower traveling body 71 shown in FIG.

  An input / output terminal of the electric system of the motor generator 83 is connected to the power storage circuit 190 via the inverter 90. The power storage circuit 190 includes a power storage module 80 (FIG. 12) and a capacitor converter 92 (FIG. 12). The inverter 90 converts the three-phase AC power supplied from the motor generator 83 into DC power based on a command from the control device 130 and supplies the DC power to the power storage circuit 190. Alternatively, the DC power supplied from the storage circuit 190 is converted into three-phase AC power and supplied to the motor generator 83. A swing motor 76 is further connected to the storage circuit 190 via another inverter 91. The power storage circuit 190 and the inverter 91 are controlled by the control device 130.

  The swing motor 76 is AC driven by a pulse width modulation (PWM) control signal from the inverter 91 and can perform both a power running operation and a regenerative operation. As the turning motor 76, for example, an IPM motor is used. An IPM motor generates a large induced electromotive force during regeneration. During the power running operation, the inverter 91 converts the DC power supplied from the power storage circuit 190 into three-phase AC power and supplies it to the turning motor 76. During the regenerative operation, the inverter 91 converts the three-phase AC power supplied from the turning motor 76 into DC power and supplies it to the power storage circuit 190.

  During the power running operation of the swing motor 76, the swing motor 76 rotates the upper swing body 70 via the speed reducer 124. At this time, the speed reducer 124 decreases the rotation speed. As a result, the rotational force generated by the turning motor 76 increases. Further, during regenerative operation, the rotational motion of the upper swing body 70 is transmitted to the swing motor 76 via the speed reducer 124, whereby the swing motor 76 generates regenerative power. At this time, the speed reducer 124 increases the rotation speed, contrary to the power running operation. Thereby, the rotation speed of the turning motor 76 can be increased.

  The resolver 122 detects the position of the rotation shaft of the turning motor 76 in the rotation direction. The detection result is input to the control device 130. By detecting the position of the rotating shaft in the rotational direction before and after the operation of the turning motor 76, the turning angle and the turning direction are derived.

  A mechanical brake 123 is connected to the rotating shaft of the turning motor 76 and generates a mechanical braking force. The braking state and the release state of the mechanical brake 123 are switched by an electromagnetic switch under the control of the control device 130.

  The pilot pump 115 generates a pilot pressure necessary for the hydraulic operation system. The generated pilot pressure is supplied to the operating device 126 via the pilot line 125. The operation device 126 includes a lever and a pedal and is operated by a driver. The operating device 126 converts the primary side hydraulic pressure supplied from the pilot line 125 into a secondary side hydraulic pressure in accordance with the operation of the driver. The secondary hydraulic pressure is transmitted to the control valve 117 via the hydraulic line 127 and to the pressure sensor 129 via the other hydraulic line 128.

  The detection result of the pressure detected by the pressure sensor 129 is input to the control device 130. Thereby, the control apparatus 130 can detect the operation state of the lower traveling body 71, the turning motor 76, the boom 82, the arm 85, and the bucket 86. In particular, in the hybrid excavator according to the thirteenth embodiment, the turning motor 76 drives the turning bearing 73. For this reason, it is desirable to detect the operation amount of the lever for controlling the turning motor 76 with high accuracy. The control device 130 can detect the operation amount of the lever with high accuracy via the pressure sensor 129.

  For the motor-generator inverter 90, the turning inverter 91, and the condenser converter 92 shown in FIG. 12, the power conversion device according to any one of the first to fourth embodiments is used. For example, U-phase, V-phase, and W-phase power modules of the motor generator inverter 90 correspond to the power modules 50A, 50B, and 50C shown in FIG. 1A, respectively. The power module 51 is a spare power module, for example.

  Since the power conversion apparatus according to any one of the first to third embodiments is used, the power modules in the motor generator inverter 90, the turning inverter 91, and the capacitor converter 92 can be evenly cooled. .

[Example 7]
FIG. 15 is a partially cutaway side view of a cargo handling work vehicle (forklift) as an example of the work machine according to the seventh embodiment. A cargo handling work vehicle according to the seventh embodiment includes a fork 211, wheels 212, an instrument panel 213, a handle 214, a lever 215, and a seat 216. A traveling motor inverter 220 and a capacitor converter 221 are mounted on the chassis via a damper or the like. Any one of the power conversion devices of the first to seventh embodiments is used for the inverter 220 for the traveling motor and the converter 221 for the electric storage device. The travel motor inverter 220 supplies power to the travel motor. The capacitor converter 221 charges and discharges the capacitor.

  The driver gets on the seat 216 and operates the handle 214, the plurality of levers 215, the accelerator pedal, the brake pedal, and other various switches. By these operations, operations such as raising and lowering the fork 211, advancing and retreating the cargo handling work vehicle, and turning right and left are performed. By combining these operations, it is possible to load and unload packages and carry them.

  Since the power conversion device according to any one of the first to fourth embodiments is used, the power modules in the traveling motor inverter 220 and the condenser converter 221 can be cooled evenly.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

DESCRIPTION OF SYMBOLS 10 Cold plate 11 Inlet 12 Run-up path 13 Tapered channel 14 Inlet side channel 15 Inlet side buffer chamber 16 Inlet side flow hole 17 Parallel channel 18 Outlet buffer chamber 19 Outlet side vent hole 20 Outlet side channel 21 Drain Outlet 22 Entrance side equalization structure 23 Exit side equalization structure 30 Housing 30A Housing lower portion 30B Upper lid 40 First cooling member 42 Second cooling member 44 Groove 46 Groove P1 First plane P2 Second plane P3 Third plane 60 Groove forming portion 62 Side wall 64 Inlet side partition wall 66 Bottom surface 68 Outlet side partition wall 69 Flow path forming portions 50A, 50B, 50C, 51 Power module 70 Upper turning body 70A Turning frame 70B Cover 70C Cabin 71 Lower traveling body 73 Turning bearing 74 Engine 75 Main pump 76 Electric motor 77 for turning 77 Oil tank 78 Cooling fan 79 Seat 80 Power storage module 81 Torque transmission mechanism 82 Boom 8 3 Motor Generator 85 Arm 86 Bucket 90 Motor Generator Inverter 91 Turning Inverter 92 Capacitor Converter 95 Storage Module Mount 96 Damper (Vibration Isolator)
97 Converter mount 98 Damper 107 Boom cylinder 108 Arm cylinder 109 Bucket cylinder 115 Pilot pump 116 High pressure hydraulic line 117 Control valve 122 Resolver 123 Mechanical brake 124 Reducer 125 Pilot line 126 Operating device 127, 128 Hydraulic line 129 Pressure sensor 130 Control device 130A CPU
130B Internal memory 135 Display device 190 Power storage circuit 101A, 101B Hydraulic motor 211 Fork 212 Wheel 213 Instrument panel 214 Handle 215 Lever 216 Seat 220 Inverter 221 for travel motor Condenser converter

Claims (8)

A power module;
A cold plate in which a plurality of parallel flow paths for flowing a cooling medium is formed in a mounting region where the power module is mounted and overlaps with the power module;
With
The cold plate is
A first cooling member having a first plane on which the power module is mounted and a second plane that is the back surface of the first plane;
A second cooling member having a third plane in intimate contact with the second plane of the first cooling member;
A plurality of grooves forming the plurality of parallel flow paths are formed in at least one of the second plane of the first cooling member and the third plane of the second cooling member. The power converter characterized by this.   The power converter according to claim 1, wherein the first cooling member is a part of a bottom surface of a case that houses the power module. At least one of the first cooling member and the second cooling member is
A plurality of inlet-side partition walls facing the upstream end face of the portion where the plurality of parallel flow paths are formed at a predetermined interval, each spaced apart in the vertical direction from the plurality of parallel flow paths A plurality of entry side bulkheads,
The region surrounded by the plurality of inlet-side partition walls and the upstream end face of the portion where the plurality of parallel flow paths are formed forms an inlet buffer chamber that makes the flow rates of the plurality of parallel flow paths uniform. The power conversion device according to claim 1, wherein the power conversion device is a power conversion device. At least one of the first cooling member and the second cooling member is
A plurality of outlet bulkheads facing a downstream end face of a portion where the plurality of parallel flow paths are formed with a predetermined interval, each spaced apart in the vertical direction from the plurality of parallel flow paths Having a plurality of outlet partitions,
A region surrounded by the plurality of outlet partitions and the downstream end face of the portion where the plurality of parallel flow paths are formed forms an output buffer chamber that makes the flow rates of the plurality of parallel flow paths uniform. The power conversion device according to claim 1, wherein the power conversion device is a power conversion device.   5. The power converter according to claim 1, wherein the plurality of grooves have a diameter of 5 mm or less.   The power converter according to claim 3, wherein the second plane is located on the power module side with respect to ½ of the height of the entry-side buffer chamber.   5. The power conversion device according to claim 1, wherein each of the plurality of grooves is formed such that a cross-sectional shape of the corresponding parallel flow path has a flat shape. A power module;
A cold plate in which a plurality of parallel flow paths for flowing a cooling medium is formed in a mounting region where the power module is mounted and overlaps with the power module;
With
The cold plate is
A first cooling member having a first plane on which the power module is mounted and a second plane that is the back surface of the first plane;
A second cooling member having a third plane in intimate contact with the second plane of the first cooling member;
A plurality of grooves forming the plurality of parallel flow paths are formed in at least one of the second plane of the first cooling member and the third plane of the second cooling member. A working machine characterized by

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