JP2010110066A - Power conversion apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the cooling performance of a power conversion apparatus equipped with a heating element. <P>SOLUTION: In the power conversion apparatus, an opening is provided in each of first and second flow paths. Each opening is closed with a metal heat sink. Multiple semiconductor chips are grouped and placed so that they are opposed to the first flow path and the second flow path through the metal heat sinks. A connecting conductor plate for supplying direct-current power to the semiconductor chips is placed on the opposite side between the first flow path and the second flow path through the metal heat sinks. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power converter that converts DC power and AC power to each other, and more particularly to a power converter that is suitable for driving an automobile.

  Since a power conversion device mounted on an electric vehicle or a hybrid vehicle generally has a large calorific value, liquid cooling is effective as one means for efficient cooling.

  As a structure for cooling the liquid, a structure is known in which cooling is performed by applying a material such as a heat conductive grease between a cooling water flow path through which a refrigerant flows and a power module. However, this structure has a drawback that the thermal resistance in the grease portion is high. On the other hand, a direct cooling type power converter that transfers heat to a cooling unit without using a heat conduction grease having a higher cooling capacity is also known (Japanese Patent Laid-Open No. 2007-295765 and Japanese Patent Laid-Open No. 2005-2005). 191502). In the direct cooling structure, the heat sink of the power module itself is provided with heat radiation fins, and the switching element is mounted on the heat sink via an insulating layer. On the other hand, an opening is provided in the cooling water flow path, the opening is closed with the heat sink, and the cooling element is directly brought into contact with the heat sink to cool the heating element.

  In such a direct cooling structure, further improvement in cooling performance is required.

JP 2007-295765 A JP 2005-191502 A

  The problem to be solved by the present invention is to improve the cooling performance of a power conversion device equipped with a heating element.

  The power conversion device according to the present invention has a first flow path and a second flow path through which a fluid cooling medium flows, and a flow path forming body in which the first flow path and the second flow path are formed in parallel. An inverter device comprising: a plurality of semiconductor chips for converting DC power to AC power; and a metal heat dissipating plate on which a connection conductor plate for supplying DC power to the semiconductor chips is mounted. Each of the flow path and the second flow path is provided with an opening, the opening is closed by the metal heat sink, and the plurality of semiconductor chips are connected to the first heat sink via the metal heat sink. The connection conductor plate is arranged on the opposite side between the first flow path and the second flow path via the metal heat dissipation plate. Be placed.

  Preferably, the U-turn portion connecting the first flow path and the second flow path is a pin fin as a heat radiating fin, and a concave portion having a curvature opposite to the U-turn curvature of the U-turn section is provided in the first cooling water flow path. And the second cooling water flow path are provided at the tip of the part that turns.

  According to the present invention, it is possible to improve the cooling performance of a power conversion device equipped with a heating element.

  A power converter according to an embodiment of the present invention will be described in detail below with reference to the drawings. First, an outline of a technique related to downsizing of a power converter according to the present embodiment will be described from the following three viewpoints. explain.

  The first viewpoint is the structural improvement of the power module. The second viewpoint is to increase the space efficiency of the wiring layout and flow path area of the power module. A third aspect is to enable the power module to be disposed also in the bent portion by promoting cooling of the flow passage bent portion, which has been considered to have low cooling performance. There is an effect in each of the above viewpoints, and a greater effect can be obtained by implementing these viewpoints in combination.

  The downsizing of the power module, which is the first viewpoint, will be described. Two sets of power modules to be described later have the same structure. Each power module is provided with a series circuit composed of an upper arm and a lower arm of an inverter circuit so as to correspond to the U-phase, V-phase, and W-phase of three-phase AC. Since the series circuit is provided side by side, the semiconductor chips of each series circuit can be arranged in an orderly manner, which leads to the miniaturization of the power module.

  In addition, as a feature of the present invention, the inverter module 144 can be integrated on the metal base 304 at a high density by arranging the power module so as to straddle both the return side and the return side of the cooling water flow path. Can be realized.

  The second viewpoint will be described. By arranging the DC wiring connected to the power module on the opposite side between the return side and the return side of the cooling water flow path via the metal base for heat dissipation, the refrigerant liquid is sent only to the part that generates heat. Therefore, the space efficiency of the cooling water passage in the power conversion device is improved, and the power conversion device can be downsized.

  The third aspect is that it is possible to arrange a power module at the bent portion by improving cooling promotion of the bent portion of the flow path connecting the return side and the return side of the cooling water flow path, which has been said to have low cooling performance. As a result, the power converter can be downsized. There are roughly two types of methods for promoting cooling of the flow path bend. The first means is to feed the refrigerant liquid to the channel bend by improving the seal on the partition located between the going side and the returning side of the cooling water channel and preventing the bypass flow. . The second means is to promote the cooling of the portion where the cooling performance is locally lowered by sending the refrigerant liquid having the vector component in the direction of the corner portion where the liquid stagnation is likely to occur in the flow path bending portion. That is. The shapes enabling these two means will be described in detail in the examples below.

  With respect to other problems different from the problems to be solved and the object effects of the invention described above, the embodiment described below solves and produces new effects. A new problem to be solved will be described below.

  1 to 5, 200 is a power converter, 10 is an upper case, 11 is a metal base plate, 12 is a housing, 13 is a cooling water inlet pipe, 14 is a cooling water outlet pipe, 420 is a cover, and 16 is a lower part. A case, 17 is an AC wiring case, 18 is an AC wiring, 19 is a cooling water flow path, and 20 is a control circuit board that holds the control circuit 172. Reference numeral 21 denotes a connector for connection to the outside, and reference numeral 22 denotes a drive circuit board that holds a driver circuit 174. Two power modules (semiconductor module units) 300 are provided, and an inverter circuit 144 is built in each power module. 700 is a laminated conductor plate, 800 is an O-ring, 304 is a metal base, 188 is an AC connector, 314 is a DC positive bus bar, 316 is a DC negative bus bar, 500 is a capacitor module, 502 is a capacitor case, 504 is a positive capacitor terminal, Reference numeral 506 denotes a negative side capacitor terminal, and 514 denotes a capacitor cell.

  The power conversion device 200 according to the present embodiment is roughly divided into components, a power module (semiconductor module unit) 300 that performs conversion between DC power and AC power, a capacitor module 500 for voltage smoothing of a DC power source, The cooling water channel 19 is used to cool the power module 300 and the like. As shown in FIG. 1, the external appearance of the power conversion device 200 according to the present embodiment is that the top surface or bottom surface of the casing 12 has a substantially rectangular shape and the cooling provided on one of the outer circumferences on the short side of the casing 12. The water inlet pipe 13 and the cooling water outlet pipe 14, the upper case 10 for closing the upper opening of the casing 12, and the lower case 16 for closing the lower opening of the casing 12 are fixedly formed. Is. Since the shape of the bottom view or the top view of the housing 12 is substantially rectangular, it is easy to attach to the vehicle and to produce easily.

  Three sets of AC wiring cases 17 for assisting connection with the motor generators 192 and 194 are provided on the outer periphery on the long side of the power conversion device 200. Two sets of AC wiring cases 17 for assisting connection with the motor generators 192 and 194 are provided on the outer periphery on the long side of the power conversion device 200. AC wiring 18 electrically connects power module 300 and motor generators 192 and 194, and transmits an AC current output from power module 300 to motor generators 192 and 194.

  The connector 21 is connected to a control circuit board 20 built in the housing 12 and transmits various external signals to the control circuit board 20. The DC negative electrode side connection terminal portion 510 and the DC positive electrode side connection terminal portion 512 electrically connect the battery 136 and the capacitor module 500. Here, in the present embodiment, the connector 21 is provided on one side of the outer peripheral surface on the short side of the housing 12. On the other hand, the direct current negative electrode side connection terminal portion 510 and the direct current positive electrode side connection terminal portion 512 are provided on the outer peripheral surface on the short side opposite to the surface on which the connector 21 is provided. That is, the connector 21 and the direct current negative electrode side connection terminal portion 510 are arranged apart from each other. Thereby, noise that enters the housing 12 from the DC negative electrode side connection terminal portion 510 and propagates to the connector 21 can be reduced, and the controllability of the motor by the control circuit board 20 can be improved.

  FIG. 2 is a perspective view in which the entire configuration of the power conversion device according to the embodiment of the present invention is disassembled into each component. A cooling water flow path 19 is provided in the middle of the housing 12, and two sets of openings 400 and 402 are formed in the upper part of the cooling water flow path 19 side by side in the flow direction. Two power modules 300 are fixed to the upper surface of the cooling water passage 19 so that the two sets of openings 400 and 402 are respectively closed by the power module 300. Each power module 300 is provided with fins 305 for radiating heat, and the fins 305 of each power module 300 protrude into the cooling water flow from the openings 400 and 402 of the cooling water channel 19, respectively.

  An opening 404 for facilitating aluminum casting is formed below the cooling water channel 19, and the opening 404 is closed by a cover 420. The cover 420 has a tapered shape in order to reduce the pressure loss due to a sudden change in the cross-sectional area by maximizing the cross-sectional area of the flow path at the position of the support part 410 that does not generate heat, thereby improving the cooling efficiency by reducing the pressure loss. I am letting. An auxiliary inverter device 43 is attached to the lower side of the cooling water passage 19. The auxiliary inverter device 43 includes a circuit similar to the inverter circuit 144 and includes a power module including a power semiconductor element constituting the inverter circuit 144. The auxiliary inverter device 43 is fixed to the lower surface of the cooling water passage 19 so that the heat dissipation metal surface of the built-in power module faces the lower surface of the cooling water passage 19.

  In addition, a lower case 16 is provided in the lower part of the cooling water flow path 19 so as to dissipate heat. It is fixed to the surface of the lower case 16 so as to face the surface. With this structure, cooling can be efficiently performed using the upper surface and the lower surface of the cooling water channel 19, which leads to downsizing of the entire power conversion device.

  When the cooling water from the inlet / outlet pipes 13 and 14 flows through the cooling water flow path 19, the heat radiation fins of the two power modules 300 provided side by side are cooled, and the entire two power modules 300 are cooled. . The auxiliary inverter device 43 provided on the lower surface of the cooling water passage 19 is also cooled at the same time.

  Further, the casing 12 provided with the cooling water flow path 19 is cooled, whereby the lower case 16 provided at the lower portion of the casing 12 is cooled, and by this cooling, the heat of the capacitor module 500 is transferred to the lower case 16 and the casing. The capacitor module 500 is cooled by being thermally conducted to the cooling water through the body 12.

  Although details will be described later, in this embodiment, the DC positive bus bar 314 and the DC negative bus bar 316 of the power module 300 are electrically and mechanically connected to the positive capacitor terminal 504 and the negative capacitor terminal 506 of the capacitor module 500, respectively. Connected within the body 12. A through hole 406 for this connection is formed.

  A control circuit board 20 and a drive circuit board 22 are arranged above the power module 300, a driver circuit 174 is mounted on the drive circuit board 22, and a control circuit 172 having a CPU is mounted on the control circuit board 20. . Further, a metal base plate 11 is disposed between the drive circuit board 22 and the control circuit board 20, and the metal base plate 11 functions as an electromagnetic shield for a circuit group mounted on both the boards 22 and 20, and also the drive circuit board. The heat generated by the control circuit board 20 and the control circuit board 20 is released and cooled. In this way, the cooling water channel 19 is provided in the central portion of the cooling water channel 19, the power module 300 for driving the vehicle is arranged on one side thereof, and the inverter device 43 for auxiliary equipment is arranged on the other side. Thus, cooling can be efficiently performed in a small space, and the entire power conversion device can be downsized. Further, by making the main structure of the cooling water channel 19 at the center of the casing by casting an aluminum material integrally with the casing 12, the cooling water channel 19 has the effect of increasing the mechanical strength in addition to the cooling effect. Further, by making the aluminum casting, the housing 12 and the cooling water flow path 19 are integrated with each other, heat conduction is improved, and cooling efficiency is improved.

  The drive circuit board 22 is provided with an inter-board connector 23 that passes through the metal base plate 11 and is connected to a circuit group of the control circuit board 20. The control circuit board 20 is provided with a connector 21 for electrical connection with the outside. The connector 21 transmits a signal to, for example, a lithium battery module mounted on the vehicle as a battery, for example, outside the power conversion device, and a signal indicating the state of the battery from the lithium battery module or a signal such as a charging state of the lithium battery. Will be sent. The board-to-board connector 23 is provided to send and receive signals to and from the control circuit 172 held on the control circuit board 20. Although not shown, the signal line and the board-to-board connector 23 are used. A switching timing signal of the inverter circuit is transmitted from the control circuit board 20 to the drive circuit board 22, and a gate drive signal which is a drive signal is generated by the drive circuit board 22 and applied to the gate electrode of the power module.

  Openings are formed in the upper part and the lower part of the casing 12, and these openings are closed by fixing the upper case 10 and the lower case 16 to the casing 12 with, for example, screws. A cooling water channel 19 is provided in the center of the housing 12, and the power module 300 and the cover 420 are fixed to the cooling water channel 19. In this way, the cooling water channel 19 is completed, and a water leak test of the water channel is performed. When the water leakage test is passed, the operation of attaching the substrate and the capacitor module 500 from the upper and lower openings of the housing 12 can be performed next. In this way, the cooling water flow path 19 is arranged in the center, and then the work for fixing the necessary parts from the upper and lower openings of the housing 12 can be performed, and the productivity is improved. Moreover, it becomes possible to complete the cooling water flow path 19 first and to attach other parts after the water leak test, which improves both productivity and reliability.

  FIG. 3 is a view in which a cooling water inlet pipe and an outlet pipe are attached to an aluminum casting product of the casing 12 having the cooling water flow path 19, FIG. 3A is a perspective view of the casing 12, and FIG. FIG. 3C is a top view of the housing 12, and FIG. 3C is a bottom view of the housing 12. As shown in FIG. 3, the casing 12 and a cooling water flow path 19 provided inside the casing 12 are integrally cast. The upper surface or the lower surface of the housing 12 has a substantially rectangular shape, and a cooling water inlet pipe 13 for taking in cooling water is provided on the side surface of one side of the rectangular short side, and the cooling water outlet pipe 14 is provided on the same side surface. Is provided.

  The cooling water that has flowed into the cooling water flow path 19 from the cooling water inlet pipe 13 flows along the long side of the rectangle in the direction of the arrow 418, and as shown by the arrow 421 near the front side of the other side of the short side of the rectangle. It turns back, flows again in the direction of the arrow 422 along the long side of the rectangle, and flows out from the outlet hole 403. Two openings 400 and 402 are formed on the outgoing side and the return side of the cooling water channel 19, respectively. The power modules 300 are fixed to the openings, respectively, and fins for heat dissipation of the power modules 300 protrude from the openings into the flow of cooling water. The power modules 300 are aligned and fixed in the flow direction of the casing 12, that is, along the long side, and by this fixing, the opening of the cooling water flow path 19 is completely blocked by, for example, the O-ring 800 or the like. The support portion 410 is formed integrally with the housing so that the The support portion 410 is located substantially at the center, and one power module 300 is fixed to the support portion 410 on the cooling water entrance / exit side, and also on the cooling water return side with respect to the support portion 410. Another one power module 300 is fixed. The screw hole 412 shown in FIG. 3B is used to fix the power module 300 on the entrance / exit side to the cooling water flow path 19, and the opening 400 is sealed by this fixing. The screw hole 414 is used to fix the folded-back power module 300 to the cooling water passage 19, and the opening 402 is sealed by this fixing. By arranging the power module 300 so as to straddle both the outgoing side and the return side of the cooling water flow path 19 in this way, the inverter circuit 144 can be integrated on the metal base 304 at a high density. Therefore, the power conversion device 200 can be greatly reduced in size.

  Since the power module 300 on the entrance / exit side is close to the cold coolant from the coolant inlet pipe 13 and the exit side, the power module 300 is cooled by the warmed coolant. On the other hand, the power module 300 on the folding side is cooled by the slightly warmed cooling water, but the temperature is lower than the cooling water near the outlet hole 403. As a result, the arrangement relationship between the folded cooling passage and the two power modules 300 has an advantage that the cooling efficiency of the two power modules 300 is balanced.

  The support 410 is used for fixing the power module 300 and is necessary for sealing the openings 400 and 402. Further, the support portion 410 has a great effect on strengthening the strength of the housing 12. The cooling water channel 19 has a folded shape as described above, and is provided with a partition 408 that separates the going-side channel and the returning-side channel, and the partition 408 is formed integrally with the support portion 410. The partition wall 408 not only simply separates the going-side flow path and the return-side flow path but also acts to increase the mechanical strength of the housing. Also, it acts as a heat transfer passage between the turn-back passages and makes the temperature of the cooling water uniform. If the temperature difference between the inlet side and the outlet side of the cooling water is large, uneven cooling efficiency increases. Although the temperature difference to some extent is unavoidable, the partition wall 408 is formed integrally with the support portion 410, so that there is an effect of suppressing the temperature difference of the cooling water.

  FIG. 3C shows the back surface of the cooling water channel 19, and an opening 404 is formed on the back surface corresponding to the support portion 410. The opening 404 is for improving the yield of the support unit 410 and the housing 12 integrated structure formed by casting the housing. The formation of the opening 404 eliminates the double structure of the support 410 and the bottom of the cooling water channel 19 in the cast product, facilitating casting and improving productivity.

  A through-hole 406 is formed between the side of the cooling water passage 19 and the long side of the rectangle to penetrate the upper and lower sides of the passage. Since electrical components are attached to both sides of the cooling water channel 19, the electrical components on both sides must be electrically connected. The through hole 406 is a hole for electrically connecting the electrical components on both sides of the cooling water channel 19.

  The housing structure shown in FIG. 3 is suitable for casting production, particularly aluminum die casting production. That is, there is an effect that an integrated structure of the cooling water flow path 19 and the housing 12 can be manufactured in a shape close to completion. Since the folded portion of the water channel indicated by the arrow 421 is a part of the opening 402, the folded portion can be integrally cast. That is, the folding path is completed by fixing the power module 300 to the opening 402. Furthermore, since the return path can be used for cooling, good miniaturization is possible. The periphery of the cooling water channel 19 is substantially perpendicular to the opening surface, and the side surface of the partition wall 408 is also substantially perpendicular. By adopting such a shape, the water channel is completed by fixing the power module 300 to the openings 400 and 402 on the upper surface and the cover 420 to the rear surface. At this point, water leaks in the water channel are inspected, and then the parts are attached, so that defective products can be quickly removed and productivity can be improved.

  FIG. 4 shows a state where the power module 300 is fixed to the upper surface opening of the cooling water passage 19 and the cover 420 is fixed to the rear surface opening. On one long side of the rectangle of the housing 12, an AC power line 186 and an AC connector 188 protrude from the housing 12.

  FIG. 6 shows a state where the power module 300 is fixed to the upper surface opening of the cooling water passage 19 and the cover 420 is fixed to the rear surface opening. On one long side of the rectangle of the housing 12, an AC power line 186 and an AC connector 188 protrude from the housing 12.

  In FIG. 4, the through hole 406 is formed inside the other long side of the rectangle of the housing 12, and a part of the laminated conductor plate 700 connected to the power module 300 through the through hole 406 can be seen. . The auxiliary inverter device 43 is disposed in the vicinity of the side surface of the housing 12 to which the DC positive electrode side connection terminal portion 512 is connected. Further, a capacitor module 500 is disposed below the auxiliary inverter device 43 (on the side opposite to the side where the cooling water flow path 19 is present). The auxiliary machine positive terminal 44 and the auxiliary machine negative terminal 45 protrude downward (in the direction in which the capacitor module 500 is disposed), and are connected to the auxiliary machine positive terminal 532 and the auxiliary machine negative terminal 534 on the capacitor module 500 side, respectively. Is done. As a result, the wiring distance from the capacitor module 500 to the auxiliary device inverter 43 is shortened, so that the auxiliary device positive terminal 532 and the auxiliary device negative terminal 534 on the capacitor module 500 side through the metal casing 12. Noise that enters the control circuit board 20 can be reduced.

  The auxiliary inverter device 43 is disposed in the gap between the cooling water flow path 19 and the capacitor module 500, and the auxiliary inverter device 43 has the same height as the cover 420. Therefore, the auxiliary inverter device 43 can be cooled and an increase in the height of the power conversion device 200 can be suppressed.

  In FIG. 4, the cooling water inlet pipe 13 and the cooling water outlet pipe 14 are fixed by screws. In the state of FIG. 4, the water leakage inspection of the cooling water channel 19 can be performed. The auxiliary inverter device 43 is attached to the one that has passed this inspection, and the capacitor module 500 is further attached.

  FIG. 5 is a cross-sectional view of the power conversion device 200 showing a state where necessary parts and wiring are performed (basic cross-sectional view taken along the line AA in FIG. 4), and the basic structure has already been described based on FIGS. As you did. Two cooling water passages 19 made of aluminum die-casting integrally with the housing 12 are provided at the center in the vertical direction in the cross section of the housing 12, and power is supplied to an opening formed on the upper surface side of the cooling water passage 19. Module 300 is installed. The left side of FIG. 5 is the first flow path 19a on the going side, and the right side is the second flow path 19b on the folded side. As described above, the opening and the cooling water flow path 19 on the return side are respectively provided with openings, and the openings are blocked by the metal base 304 for heat dissipation of the power module 300 so as to straddle both the return side and the return side. Fins 305 for heat dissipation provided on the metal base 304 protrude from the opening in the flow of cooling water. An auxiliary inverter device 43 is fixed to the lower surface side of the cooling water passage 19.

  On the left side of FIG. 5, an AC power line 186 having a rectangular parallelepiped cross section, that is, a bus bar shape, extends from the inside of the power module 300 to form an AC connector 188. A through hole 406 is formed on the right side of FIG. 5, and the DC positive / negative bus bars 314 and 316 of the power module 300 extend from the capacitor module 500 via the DC positive bus bar 702 and the DC negative bus bar 706. The positive electrode conductor plate 507 and the negative electrode conductor plate 505 are directly and electrically connected. A cooling water flow path 19 that reciprocates substantially in the center of the housing 12 in the long side direction of the rectangle is arranged, and an AC connector 188 and DC positive / negative electrode bus bars 314 and 316 are arranged in a direction substantially perpendicular to the flow direction of the cooling water. Therefore, the electrical wiring is arranged in an orderly manner, which leads to the miniaturization of the power conversion device 200. Furthermore, since the positive / negative conductor plates 315 and 317 on the DC side of the power module 300 and the AC power line 186 project outside the power module 300 to form connection terminals, the structure is very simple, and other connection conductors are used. Because it is not done, it is miniaturized. This structure improves productivity and improves reliability. The through hole 406 connecting the DC positive / negative bus bars 314, 316 of the power module 300 and the positive / negative capacitor terminals 504, 506 of the capacitor module 500 is a frame inside the housing 12 and the cooling water channel 19. The isolated structure improves reliability.

  A lower case 16 made of aluminum having excellent thermal conductivity is provided in the lower opening of the housing 12. A metal capacitor case 502 of the capacitor module 500 is fixed to the lower case 16. Since the lower case 16 is cooled by the cooling water flowing through the cooling water passage 19 via the housing 12, the heat generated inside the capacitor module 500 is radiated through the lower case 16.

  The power module 300 having a large calorific value is fixed to one surface of the cooling water channel 19 and the fins 305 of the power module 300 protrude from the opening of the cooling water channel 19 into the water channel for efficient cooling. The auxiliary inverter device 43 having a large amount of heat is cooled on the other surface of the cooling water flow path 19, and the capacitor module 500 having the next largest heat generation amount is cooled via the housing 12 and the lower case 16. Thus, since it is set as the cooling structure match | combined with much heat dissipation, while cooling efficiency and reliability improve, the power converter device 200 can be reduced more in size.

  Further, since the auxiliary inverter device 43 is fixed to the side of the capacitor module 500 of the cooling water passage 19, the capacitor module 500 can be used as a smoothing capacitor of the auxiliary inverter device 43. In this case, the wiring distance is shortened. There is. In addition, since the wiring distance is short, the inductance can be reduced.

  A driving circuit board 22 holding the driver circuit 174 of FIG. 2 is disposed above the power module 300 and fixed above one surface of the cooling water flow path 19, and further dissipates heat above the power module 300. A control circuit board 20 is provided with a connector 21 with a metal base plate 11 acting as an electromagnetic shield. A control circuit 172 shown in FIG. 2 is mounted on the control circuit board 20. By fixing the upper case 10 to the housing 12, the power conversion device 200 according to the present embodiment is configured.

  As described above, since the drive circuit board 22 is arranged between the control circuit board 20 and the power module 300, the operation timing of the inverter circuit is transmitted from the control circuit board 20 to the drive circuit board 22, and based on that. A gate signal is generated by the drive circuit board 22 and applied to each gate of the power module 300. Since the control circuit board 20 and the drive circuit board 22 are thus arranged along the electrical connection relationship, the electrical wiring can be simplified and the power converter 200 can be downsized.

  The power module 300 is fixed to one surface of the cooling water channel 19 and the auxiliary inverter device 43 is fixed to the other surface, so that the power module 300 and the auxiliary inverter device 43 are simultaneously cooled by the cooling water channel 19. To do. In this case, the power module 300 has a greater cooling effect because the fins for heat dissipation are in direct contact with the cooling water in the cooling water passage 19. Further, the casing 12 is cooled by the cooling water flow path 19, and the lower case 16 and the metal base plate 11 are fixed to the casing 12, thereby cooling through the lower case 16 and the metal base plate 11. Since the metal case of the capacitor module 500 is fixed to the lower case 16, the capacitor module 500 is cooled via the lower case 16 and the housing 12. Further, the control circuit board 20 and the drive circuit board 22 are cooled via the metal base plate 11. In this way, the cooling water flow path 19 is provided in the center, the metal base plate 11 is provided on one side, and the lower case 16 is provided on the other side. It can cool well. Also, the components are neatly arranged inside the power conversion device 200, and the size can be reduced.

  Further, it becomes possible to perform a water leak test with the power module 300 attached to the cooling water flow path 19 in the central portion, and after the test is completed, necessary parts can be fixed from above and below the housing 12, so that productivity is improved. Is excellent.

  The characteristics of the power converter according to the embodiment of the present invention will be further described. In the overall laminated configuration and cooling structure of the power conversion device according to the present embodiment, the power module 300 that is the main heating element is directly cooled by the cooling water that flows through the cooling water passage 19, and the capacitor module 500 that is the heating element is the cooling water flow. The power module 300 and the power module 300 are sandwiched with the path 19 therebetween, and the sandwich structure of the sandwich reduces the thickness and size of the power converter.

  The heat radiator that performs the heat dissipation function of the power conversion device is primarily the cooling water flow path 19, but the metal base plate 11 also performs this function (the metal base plate 11 is used to perform the heat dissipation function). Provided). The metal base plate 11 performs an electromagnetic shielding function, receives heat from the control circuit board 20 and the drive circuit board 22, conducts heat to the housing 12, and is radiated by the cooling water in the cooling water flow path 19. Further, the lower case 16 is also made of a material having good thermal conductivity, receives heat generated from the capacitor module 500, conducts heat to the cooling water channel 19, and is radiated by the cooling water in the cooling water channel 19. Further, on the other side of the cooling water channel 19 which is the lower cover 15 side, a relatively small capacity inverter device 43 for use in a vehicle air conditioner, an oil pump, or a pump for other purposes may be installed. Good. The heat generated from the auxiliary inverter device 43 is radiated by the cooling water in the cooling water passage 19 through the intermediate frame of the housing 12.

  As described above, the power converter according to the present embodiment has a multilayer structure in which the radiator is a three-layered structure, that is, the metal base plate 11, the cooling water channel 19, and the lower case 16, and these The heat dissipating elements are hierarchically installed adjacent to the respective heat generating elements (power module 300, circuit boards 20, 22 and capacitor module 500). In the center of the hierarchical structure, there is a cooling water flow path 19 that is a main radiator, and the metal base plate 11 and the lower case 16 are structured to transmit heat to the cooling water in the cooling water flow path 19 through the housing 12. . Three heat radiators (cooling water flow path 19, metal base plate 11, lower case 16) are accommodated in the housing 12 to improve heat dissipation and contribute to reduction in thickness and size.

  FIG. 11A is an upper perspective view of the power module 300 according to this embodiment, and FIG. 11B is a top view of the power module 300. FIG. 12 is an exploded perspective view of a DC terminal of the power module 300 according to the present embodiment. FIG. 13 is a cross-sectional view in which the power module case 302 is partially transparent to make the structure of the DC bus bar easier to understand. FIG. 12A is a diagram in which one of the metal base 304 and three upper and lower arm series circuits, which are components of the power module 300, is extracted. FIG. 12B is an exploded perspective view of the metal base 304, the circuit wiring pattern, and the insulating substrate 334.

  302 is a power module case, 304 is a metal base, 305 is a fin (see FIG. 13), 314 is a DC positive bus bar, 316 is a DC negative bus bar, 318 is insulating paper (see FIG. 12), and 320U / 320L is a power module control Terminal 328, IGBT for upper arm, 330 for IGBT for lower arm, 156/166 for diode, 334 for insulating substrate (see FIG. 13), 334k for circuit wiring pattern on insulating substrate 334 (see FIG. 13), Reference numeral 334r denotes a circuit wiring pattern 337 (see FIG. 13) under the insulating substrate 334, respectively.

  The power module 300 is roughly divided into, for example, a semiconductor module portion including wiring in a power module case 302 made of a resin material, a metal base 304 made of a metal material such as Cu, Al, AlSiC, and a connection terminal ( DC positive electrode bus bar 314, control terminal 320U, etc.). As terminals connected to the outside, the power module 300 includes U, V, and W phase AC terminals 159 for connection to the motor, and a DC positive bus bar 314 and a DC negative bus bar 316 connected to the capacitor module 500. ing.

  The semiconductor module portion is provided with IGBTs 328 and 330 for upper and lower arms, diodes 156/166 and the like on an insulating substrate 334, and is protected by a resin or silicon gel (not shown). The insulating substrate 334 may be a ceramic substrate or a thinner insulating sheet.

  FIG. 11B shows an arrangement configuration in which the upper and lower arm series circuits are specifically arranged on the insulating substrate 334 made of ceramic having good thermal conductivity fixed to the metal base 304. It is explanatory drawing which shows a figure and its function. The IGBTs 328 and 330 and the diodes 327 and 332 shown in FIG. 11B respectively connect two chips in parallel to form an upper arm and a lower arm, and increase the current capacity that can be supplied to the upper and lower arms.

  As shown in FIG. 12, the DC terminal 313 built in the power module 300 has a laminated structure of a DC negative electrode bus bar 316 and a DC positive electrode bus bar 314 with an insulating paper 318 interposed therebetween (dotted line portion in FIG. 12). Further, the ends of the DC negative electrode bus bar 316 and the DC positive electrode bus bar 314 are bent in opposite directions to form a negative electrode connection part 316a and a positive electrode connection part 314a for electrically connecting the laminated conductor plate 700 and the power module 300. To do. By providing two connection portions 314a (or 316a) with the laminated conductor plate 700, the average distances from the negative electrode connection portion 316a and the positive electrode connection portion 314a to the three upper and lower arm series circuits are substantially equal. Variations in parasitic inductance in 300 can be reduced.

  Further, when the DC positive electrode bus bar 314, the insulating paper 318, and the DC negative electrode bus bar 316 are stacked and assembled, the negative electrode connection portion 316a and the positive electrode connection portion 314a are bent in opposite directions. The insulating paper 318 is bent along the negative electrode connecting portion 316a to ensure an insulating creepage distance between the positive and negative terminals. As the insulating paper 318, when heat resistance is required, a sheet in which polyimide, meta-aramid fiber, polyester with improved tracking properties, or the like is used is used. In addition, in consideration of defects such as pin fall, two sheets are stacked to increase reliability. Also, in order to prevent tearing or tearing, the corners are rounded or the sag surface at the time of punching faces the insulating paper so that the edge of the terminal does not touch the insulating paper. In this embodiment, insulating paper is used as the insulator, but as another example, the terminal may be coated with the insulator. In order to reduce the parasitic inductance, for example, in the case of a 600V withstand voltage power module, the distance between the positive electrode and the negative electrode is 0.5 mm or less, and the thickness of the insulating paper is half or less.

  Further, the DC positive bus bar 314 and the DC negative bus bar 316 have connection ends 314K and 316K for connecting to the circuit wiring pattern 334K. There are two connection ends 314K, 316K for each phase (U, V, W phase). Thereby, as will be described later, it is possible to connect to a circuit wiring pattern in which two small loop current paths are formed for each arm of each phase. Each connection end 314K, 316K protrudes in the direction of the circuit wiring pattern 334K, and its tip is bent to form a joint surface with the circuit wiring pattern 334K. The connection ends 314K, 316K and the circuit wiring pattern 334K are connected via solder or the like, or directly connected to each other by ultrasonic welding.

  The power module 300, particularly the metal base 304, expands and contracts due to a temperature cycle. Due to the expansion and contraction, the connection portion between the connection ends 314K and 316K and the circuit wiring pattern 334K may be cracked or broken. Therefore, in the power module 300 according to the present embodiment, as illustrated in FIG. 12, the laminated flat surface portion 319 formed by laminating the DC positive electrode bus bar 314 and the DC negative electrode bus bar 316 is provided on the side on which the insulating substrate 334 is mounted. Thus, the laminated flat surface portion 319 can be warped in response to the warping of the metal base 304 caused by the expansion and contraction described above. It becomes. Therefore, the rigidity of the connection ends 314 </ b> K and 316 </ b> K formed integrally with the laminated flat surface portion 319 can be reduced with respect to the warp of the metal base 304. Therefore, the stress applied in the vertical direction of the joint surface between the connection ends 314K and 316K and the circuit wiring pattern 334K can be relaxed, and cracks or breakage of the joint surface can be prevented.

  In addition, the lamination plane part 319 according to the present embodiment has the width direction length of the lamination plane part 319 so that the metal base 304 can bend in response to both the width direction and the depth direction curvature. The length in the depth direction is increased to 130 mm and the length in the depth direction to 10 mm. In addition, the thickness of each of the stacked flat surface portions 319 of the DC positive electrode bus bar 314 and the DC negative electrode bus bar 316 is set to be relatively thin as 1 mm so that the warping operation is easily performed.

  As shown in FIG. 13, the metal base 304 has a fin shape 305 on the opposite side of the insulating substrate 334 in order to efficiently radiate heat to the cooling water by being immersed in the cooling water flow path. In addition, the metal base 304 is mounted with an IGBT or a diode constituting an inverter circuit on one surface, and a resin power module case 302 is provided on the outer periphery of the metal base 304. The fin 305 is brazed to the other surface of the metal base 304 or the metal base 304 and the fin 305 are integrally formed by forging. The metal base 304 and the fin 305 are integrally formed by forging, so that the productivity of the power module 300 is improved, the thermal conductivity from the metal base 304 to the fin 305 is improved, and the heat dissipation of the IGBT and the diode is improved. Can be made. Further, by setting the Vickers hardness of the metal base 304 to 60 or more, the ratchet deformation of the metal base 304 caused by the temperature cycle can be suppressed, and the sealing performance between the metal base 304 and the housing 12 can be improved. Further, as shown in FIG. 13A, fins 305 are provided corresponding to the upper and lower arms, respectively, and these fins 305 project into the water channel from the opening of the reciprocating cooling water channel 19. A metal surface around the fin 305 of the metal base 304 is used to close an opening provided in the cooling water channel 19.

  In addition, although the fin 305 shape of this embodiment is a pin type, as another embodiment, the straight type formed along the flow direction of cooling water may be sufficient. When the straight type is used for the fin 305 shape, the pressure for flowing the cooling water can be reduced, and when the pin type is used, the cooling efficiency can be improved.

  An insulating substrate 334 is fixed to one surface of the metal base 304, and an upper arm IGBT 328, an upper arm diode 156, a lower arm IGBT 330, and a lower arm are fixed to the insulating substrate 334 with solder 337. The chip of the diode 166 is fixed.

  FIG. 6 is a diagram showing a relative positional relationship between the semiconductor element and the fin layout in the U-turn portion that connects the return side and the return side of the cooling water flow path.

  As will be described later with reference to FIG. 15, the inverter single-phase circuit in the power module 300 is composed of an upper arm composed of a pair of IGBT and a diode on the DC positive terminal side, and another IGBT and diode pair on the DC negative terminal side. AC power is taken out from an intermediate electrode connecting the upper arm and the lower arm. In the case of a three-phase circuit used for motor control or the like, there are three sets of the upper and lower arms, and DC power is supplied to each of the three phases. Therefore, a space is required in the power module 300 for arranging wiring for connecting the upper and lower arms, wiring for supplying DC power to the IGBT, and the like.

  The aforementioned wiring is less necessary to be cooled than an IGBT or a diode. The components in the power module 300 are most required to improve the cooling performance for the IGBT and the diode. On the other hand, it is necessary to reduce the size of the power conversion device while suppressing the deterioration of the cooling performance. Can be reduced.

  Therefore, in the present embodiment, the IGBTs 328 and 330 and the diodes 156 and 166 are separately arranged so as to face the first flow path and the second flow path through the metal base 304, and further, the direct current positive electrode bus bar 314 and the direct current The negative electrode bus bar 316 is disposed on the opposite side between the first flow path and the second flow path via the metal base 304. Here, in the present embodiment, the first flow path means the forward path from the inlet of the flow path 19 to the U-turn part 424, while the second flow path is the return path from the U-turn part 424 to the outlet of the flow path 19. Means. The first flow path and the second flow path may be formed by arranging two substantially linear flow paths in parallel.

  Due to the above arrangement relationship, as shown in FIG. 6, the DC positive electrode bus bar 314 and the DC negative electrode bus bar 316 (the one-dot chain line in FIG. 6) are installed at a position overlapping the partition wall 408 where the cooling water does not flow. The IGBT and the diode are installed at a position overlapping the fin 305 that is in direct contact with water. Therefore, the generated heat of the IGBT or the diode that needs to be cooled most is transferred to the fin 305 formed directly under the IGBT, while the generated heat of the DC positive bus bar 314 and the DC negative bus bar 316 passes through the metal base 304. Heat is transferred to the fins 305. Thereby, size reduction of a power converter device can be achieved, suppressing the fall of the cooling performance of a heat generating element. Furthermore, since an increase in the channel area can be suppressed, the power converter can be downsized and the pressure loss of the entire channel can be reduced.

  In addition, the AC terminal 159 formed on one side of the power module 300 is not disposed at a position overlapping the fins 305 but is disposed at a position overlapping the flow path forming body 19C. Thereby, size reduction of a power converter device can be achieved, suppressing the fall of the cooling performance of a heat generating element.

  When the U-shaped cooling water flow path is used, there is a possibility that a bypass flow 423 as shown in FIG. 6 is generated while the cooling water flows from the flow path inlet to the U-turn portion. Therefore, an amount of cooling water necessary for cooling the heating element arranged in the vicinity of the U-turn portion is not transported, and the heating element may not be sufficiently cooled. In particular, when the cooling water flow path completed by closing the opening formed so as to straddle the return side and the return side of the cooling water flow path with a plate material (the metal base 304 in the present embodiment) is used, There is a possibility that the bypass flow 423 is generated.

  Therefore, in the present embodiment, an O-ring 800 is provided on the partition wall 408, and the O-ring 800 is preferably bent so as to have a double structure with respect to the flow direction of the bypass flow 423 as shown in FIG. Installed on the partition wall 408. Thereby, since the sealing performance is improved and the bypass flow 423 can be prevented, the cooling water can be transported to the U-turn portion, and the cooling of the semiconductor element disposed in the U-turn portion can be promoted. In this embodiment, the O-ring 800 is used as the sealing material, but a resin material, liquid seal, packing, or the like may be used instead of the O-ring.

  Further, by providing the partition wall 408 with screw holes 414a for fixing the power module, the allowable deflection amount of the metal base 304 of the power module can be increased, and the deflection amount due to the water pressure of the cooling water by driving the pump can be decreased. Thereby, the sealing performance between the partition 408 and the metal base 304 is improved, and the bypass flow 423 can be suppressed. In particular, in the O-ring 800 having a double structure with respect to the flow direction of the bypass flow 423, when the screw hole 414a is formed so as to be sandwiched between the double structures, the sealing performance can be improved while suppressing the enlargement of the entire apparatus. Improvements can be made.

  In the embodiment of the present invention, since the IGBT 328/330 is disposed at a position farther from the partition wall 408 than the diode 156/166, by utilizing the inertial force (centrifugal force) of the flow at the U-turn portion, Since the vector 421b in the downstream portion of the turn has a component in the direction toward the corner portion, it is possible to promote the cooling of the portion where the cooling performance is locally lowered.

  Further, in the present embodiment, as shown in FIG. 6, by forming a recess in the end portion 424 of the partition wall 408, the U-turn upstream portion and the U-turn downstream portion vector 421a / 421b are components in the direction toward the corner portion. Therefore, the cooling can be promoted even in a portion where the liquid easily stagnates.

  Further, in the present embodiment, the fin 305 has a pin shape, and the fin 305 is formed from the vicinity of the end portion 424 of the partition 408 to the vicinity of the end portion of the U-turn portion. That is, the fin 305 is formed on the arrow direction side of the line AA in FIG. On the other hand, by providing a gap where no fin is present at the end of the U-turn part, it becomes possible to send liquid toward the end part 424 (vector 421a in the U-turn upstream part). Thereby, the fall of the cooling efficiency of a U-turn part can be prevented, and IGBT328,330 and the diodes 156,166 can be arrange | positioned at a U-turn part. Therefore, the channel area can be reduced, and as a result, the power converter can be reduced in size and the pressure loss of the entire channel can be reduced.

  In order to send cooling water to the U-turn part, guide vanes such as flat plate fins may be used instead of pin fins. However, flat plate fins have low cooling performance and connect the return side and the return side. For this reason, there is a problem that it is difficult to reduce the size in order to secure the space, and therefore, a non-directional heat sink such as a pin fin is advantageous for the U-turn portion.

  The power conversion device according to the embodiment of the present invention can be applied to a hybrid vehicle or a pure electric vehicle. As a representative example, the power conversion device according to the embodiment of the present invention is applied to a hybrid vehicle. The control configuration and the circuit configuration of the power converter will be described with reference to FIGS. 14 and 15. FIG. 14 is a diagram showing a control block of the hybrid vehicle.

  The power conversion device according to the embodiment of the present invention is used in a vehicle-mounted power conversion device for a vehicle-mounted electrical system mounted on an automobile, in particular, a vehicle drive electrical system, and has a very severe mounting environment and operational environment. The inverter device will be described as an example. A vehicle drive inverter device is provided in a vehicle drive electrical system as a control device for controlling the drive of a vehicle drive motor, and a DC power supplied from an in-vehicle battery or an in-vehicle power generator constituting an in-vehicle power source is a predetermined AC power. Then, the AC power obtained is supplied to the vehicle drive motor to control the drive of the vehicle drive motor. Further, since the vehicle drive motor also has a function as a generator, the vehicle drive inverter device also has a function of converting the AC power generated by the vehicle drive motor into DC power according to the operation mode. Yes. The converted DC power is supplied to the on-vehicle battery.

  The configuration of the present embodiment is optimal as a power conversion device for driving a vehicle such as an automobile or a truck. However, other power conversion devices such as a power conversion device such as a train, a ship, and an aircraft, and a factory facility are also included. Applicable to industrial power converters used as drive motor control devices, or household power conversion devices used in home solar power generation systems and motor control devices that drive household appliances It is.

  In FIG. 14, a hybrid electric vehicle (hereinafter referred to as “HEV”) 110 is one electric vehicle, and includes two vehicle drive systems. One of them is an engine system that uses an engine 120 that is an internal combustion engine as a power source. The engine system is mainly used as a drive source for HEV. The other is an in-vehicle electric system using motor generators 192 and 194 as a power source. The in-vehicle electric system is mainly used as an HEV drive source and an HEV power generation source. The motor generators 192 and 194 are, for example, synchronous machines or induction machines, and operate as both a motor and a generator depending on the operation method.

  A front wheel axle 114 is rotatably supported at the front portion of the vehicle body. A pair of front wheels 112 are provided at both ends of the front wheel axle 114. A rear wheel axle (not shown) is rotatably supported on the rear portion of the vehicle body. A pair of rear wheels are provided at both ends of the rear wheel axle. The HEV of this embodiment employs a so-called front wheel drive system in which the main wheel driven by power is the front wheel 112 and the driven wheel to be driven is the rear wheel. You may adopt.

  A front wheel side differential gear (hereinafter referred to as “front wheel side DEF”) 116 is provided at the center of the front wheel axle 114. The front wheel axle 114 is mechanically connected to the output side of the front wheel side DEF 116. The output shaft of the transmission 118 is mechanically connected to the input side of the front wheel side DEF 116. The front wheel side DEF 116 is a differential power distribution mechanism that distributes the rotational driving force that is shifted and transmitted by the transmission 118 to the left and right front wheel axles 114. The output side of the motor generator 192 is mechanically connected to the input side of the transmission 118. The output side of the engine 120 and the output side of the motor generator 194 are mechanically connected to the input side of the motor generator 192 via the power distribution mechanism 122. Motor generators 192 and 194 and power distribution mechanism 122 are housed inside the casing of transmission 118.

  The motor generators 192 and 194 are synchronous machines having a permanent magnet on the rotor, and the AC power supplied to the armature windings of the stator is controlled by the inverter devices 140 and 142, thereby the motor generators 192 and 194. Is controlled. A battery 136 is electrically connected to the inverter devices 140 and 142, and power can be exchanged between the battery 136 and the inverter devices 140 and 142.

  In the present embodiment, the first motor generator unit composed of the motor generator 192 and the inverter device 140 and the second motor generator unit composed of the motor generator 194 and the inverter device 142 are provided. ing. That is, in the case where the vehicle is driven by the power from the engine 120, when assisting the driving torque of the vehicle, the second motor generator unit is operated as the power generation unit by the power of the engine 120 to generate power. The first electric power generation unit is operated as an electric unit by the obtained electric power. Further, in the same case, when assisting the vehicle speed of the vehicle, the first motor generator unit is operated by the power of the engine 120 as a power generation unit to generate power, and the second motor generator unit is generated by the electric power obtained by the power generation. Operate as an electric unit.

  In the present embodiment, the vehicle can be driven only by the power of the motor generator 192 by operating the first motor generator unit as an electric unit by the electric power of the battery 136. Furthermore, in the present embodiment, the battery 136 can be charged by generating power by operating the first motor generator unit or the second motor generator unit as the power generation unit by the power of the engine 120 or the power from the wheels.

  The battery 136 is also used as a power source for driving an auxiliary motor 195. The auxiliary machine is, for example, a motor that drives a compressor of an air conditioner or a motor that drives a hydraulic pump for control. DC power is supplied from the battery 136 to the inverter device 43 and converted into AC power by the inverter device 43. To the motor 195. The inverter device 43 has the same function as the inverter devices 140 and 142, and controls the phase, frequency, and power of alternating current supplied to the motor 195. For example, the motor 195 generates torque by supplying AC power having a leading phase with respect to the rotation of the rotor of the motor 195. On the other hand, by generating the delayed phase AC power, the motor 195 acts as a generator, and the motor 195 is operated in a regenerative braking state. Such a control function of the inverter device 43 is the same as the control function of the inverter devices 140 and 142. Since the capacity of the motor 195 is smaller than the capacity of the motor generators 192 and 194, the maximum conversion power of the inverter device 43 is smaller than that of the inverter devices 140 and 142, but the circuit configuration of the inverter device 43 is basically the circuit of the inverter devices 140 and 142. Same as the configuration.

  The inverter devices 140 and 142, the inverter device 43, and the capacitor module 500 are in an electrical close relationship. Furthermore, there is a common point that measures against heat generation are necessary. It is also desired to make the volume of the device as small as possible. From these points, the power conversion device described in detail below includes the inverter devices 140 and 142, the inverter device 43, and the capacitor module 500 in the casing of the power conversion device. With this configuration, a small and highly reliable device can be realized.

  Further, by incorporating the inverter devices 140 and 142, the inverter device 43, and the capacitor module 500 in one housing, it is effective in simplifying wiring and taking measures against noise. In addition, the inductance of the connection circuit between the capacitor module 500, the inverter devices 140 and 142, and the inverter device 43 can be reduced, the spike voltage can be reduced, heat generation can be reduced, and heat dissipation efficiency can be improved.

  Next, the electric circuit configuration of the inverter devices 140 and 142 or the inverter device 43 will be described with reference to FIG. In the embodiment shown in FIGS. 14 and 15, the case where the inverter devices 140 and 142 or the inverter device 43 are individually configured will be described as an example. Since the inverter devices 140 and 142 or the inverter device 43 have the same functions and the same functions, the inverter device 140 will be described here as a representative example.

  The power conversion device 200 according to the present embodiment includes an inverter device 140 and a capacitor module 500, and the inverter device 140 includes an inverter circuit 144 and a control unit 170. The inverter circuit 144 includes a plurality of upper and lower arm series circuits 150 including an IGBT 328 (insulated gate bipolar transistor) and a diode 156 that operate as an upper arm, and an IGBT 330 and a diode 166 that operate as a lower arm (FIG. 15). In this example, three upper and lower arm series circuits 150, 150, 150), an AC power line (AC bus bar) 186 from the middle point (intermediate electrode 169) of each upper and lower arm series circuit 150 to the motor generator 192 through the AC terminal 159, It is a configuration to connect. In addition, the control unit 170 includes a driver circuit 174 that drives and controls the inverter circuit 144 and a control circuit 172 that supplies a control signal to the driver circuit 174 via the signal line 176.

  The IGBTs 328 and 330 of the upper arm and the lower arm are switching power semiconductor elements, operate in response to a drive signal output from the control unit 170, and convert DC power supplied from the battery 136 into three-phase AC power. . The converted electric power is supplied to the armature winding of the motor generator 192.

  The inverter circuit 144 is configured by a three-phase bridge circuit, and a DC positive bus bar 314 in which upper and lower arm series circuits 150, 150, 150 for three phases are electrically connected to the positive side and the negative side of the battery 136, respectively. And the DC negative electrode bus bar 316 are electrically connected in parallel.

  In the present embodiment, the use of IGBTs 328 and 330 as switching power semiconductor elements is exemplified. The IGBTs 328 and 330 include collector electrodes 153 and 163, emitter electrodes (signal emitter electrode terminals 155 and 165), and gate electrodes (gate electrode terminals 154 and 164). Diodes 156 and 166 are electrically connected between the collector electrodes 153 and 163 of the IGBTs 328 and 330 and the emitter electrode as shown. The diodes 156 and 166 have two electrodes, a cathode electrode and an anode electrode, and the cathode electrode serves as the collector electrode of the IGBTs 328 and 330 so that the direction from the emitter electrode to the collector electrode of the IGBTs 328 and 330 is the forward direction. The anode electrodes are electrically connected to the emitter electrodes of the IGBTs 328 and 330, respectively. A MOSFET (metal oxide semiconductor field effect transistor) may be used as the switching power semiconductor element. In this case, the diode 156 and the diode 166 are not necessary.

  Upper and lower arm series circuit 150 is provided for three phases corresponding to each phase winding of the armature winding of motor generator 192. The three upper and lower arm series circuits 150, 150, 150 are respectively connected to the motor generator 192 via the intermediate electrode 169 and the AC terminal 159 that connect the emitter electrode of the IGBT 328 and the collector electrode 163 of the IGBT 330, the V phase, and the W phase. Is forming. The upper and lower arm series circuits are electrically connected in parallel. The collector electrode 153 of the upper arm IGBT 328 is connected to the positive capacitor electrode of the capacitor module 500 via the positive terminal (P terminal) 157, and the emitter electrode of the lower arm IGBT 330 is connected to the capacitor module 500 via the negative terminal (N terminal) 158. Are respectively electrically connected (connected by a DC bus bar). The intermediate electrode 169 corresponding to the middle point portion of each arm (the connection portion between the emitter electrode of the IGBT 328 of the upper arm and the collector electrode of the IGBT 330 of the lower arm) is connected to the corresponding phase winding of the armature winding of the motor generator 192 with an AC connector. It is electrically connected via 188.

  Capacitor module 500 is for configuring a smoothing circuit that suppresses fluctuations in DC voltage caused by the switching operation of IGBTs 328 and 330. The positive electrode side of the battery 136 is electrically connected to the positive electrode side capacitor electrode of the capacitor module 500, and the negative electrode side of the battery 136 is electrically connected to the negative electrode side capacitor electrode of the capacitor module 500 via the DC connector 138. Thus, the capacitor module 500 is connected between the collector electrode 153 of the upper arm IGBT 328 and the positive electrode side of the battery 136, and between the emitter electrode of the lower arm IGBT 330 and the negative electrode side of the battery 136. Electrically connected in parallel to the series circuit 150.

  The control unit 170 is for operating the IGBTs 328 and 330, and generates a timing signal for controlling the switching timing of the IGBTs 328 and 330 based on input information from other control devices or sensors. And a drive circuit 174 that generates a drive signal for switching the IGBTs 328 and 330 based on the timing signal output from the control circuit 172.

  The control circuit 172 includes a microcomputer (hereinafter referred to as “microcomputer”) for calculating the switching timing of the IGBTs 328 and 330. The microcomputer receives as input information the target torque value required for the motor generator 192, the current value supplied from the upper and lower arm series circuit 150 to the armature winding of the motor generator 192, and the magnetic pole of the rotor of the motor generator 192. The position has been entered. The target torque value is based on a command signal output from a host controller (not shown). The current value is detected based on the detection signal output from the current sensor 180. The magnetic pole position is detected based on a detection signal output from a rotating magnetic pole sensor (not shown) provided in the motor generator 192. In the present embodiment, the case where the current values of three phases are detected will be described as an example, but the current values for two phases may be detected.

  The microcomputer in the control circuit 172 calculates the d and q axis current command values of the motor generator 192 based on the target torque value, and the calculated d and q axis current command values and the detected d and q The voltage command values for the d and q axes are calculated based on the difference from the current value of the shaft, and the calculated voltage command values for the d and q axes are calculated based on the detected magnetic pole position. Convert to W phase voltage command value. Then, the microcomputer generates a pulse-like modulated wave based on the comparison between the fundamental wave (sine wave) and the carrier wave (triangular wave) based on the voltage command values of the U-phase, V-phase, and W-phase, and the generated modulation The wave is output to the driver circuit 174 as a PWM (pulse width modulation) signal.

  When driving the lower arm, the driver circuit 174 amplifies the PWM signal, and when the driver circuit 174 drives the upper arm to the gate electrode of the corresponding IGBT 330 of the lower arm, the driver circuit 174 sets the level of the reference potential of the PWM signal. After shifting to the level of the reference potential of the upper arm, the PWM signal is amplified and output as a drive signal to the gate electrode of the corresponding IGBT 328 of the upper arm. As a result, each IGBT 328, 330 performs a switching operation based on the input drive signal.

  In addition, the control unit 170 performs abnormality detection (overcurrent, overvoltage, overtemperature, etc.) to protect the upper and lower arm series circuit 150. For this reason, sensing information is input to the control unit 170. For example, information on the current flowing through the emitter electrodes of the IGBTs 328 and 330 is input to the corresponding drive units (ICs) from the signal emitter electrode terminals 155 and 165 of each arm. Thereby, each drive part (IC) detects overcurrent, and when overcurrent is detected, the switching operation of corresponding IGBT328,330 is stopped, and corresponding IGBT328,330 is protected from overcurrent. Information on the temperature of the upper and lower arm series circuit 150 is input to the microcomputer from a temperature sensor (not shown) provided in the upper and lower arm series circuit 150. In addition, voltage information on the DC positive side of the upper and lower arm series circuit 150 is input to the microcomputer. The microcomputer performs over-temperature detection and over-voltage detection based on the information, and when an over-temperature or over-voltage is detected, it stops the switching operation of all the IGBTs 328 and 330, and the upper and lower arm series circuit 150 (subtract) The semiconductor module including the circuit 150 is protected from overtemperature or overvoltage.

  The conduction and cut-off operations of the IGBTs 328 and 330 of the upper and lower arms of the inverter circuit 144 are switched in a fixed order, and the current of the stator winding of the motor generator 192 at this switching flows through a circuit formed by the diodes 156 and 166.

  As shown in the figure, the upper and lower arm series circuit 150 includes a positive terminal (P terminal, positive terminal) 157, a negative terminal (N terminal 158, negative terminal), an AC terminal 159 from the intermediate electrode 169 of the upper and lower arms, and an upper arm signal. A terminal for signal (signal emitter electrode terminal) 155, a gate electrode terminal 154 for the upper arm, a signal terminal (signal emitter electrode terminal for signal) 165 for the lower arm, and a gate terminal electrode 164 for the lower arm. The power conversion device 200 has a DC connector 138 on the input side and an AC connector 188 on the output side, and is connected to the battery 136 and the motor generator 192 through the connectors 138 and 188, respectively. Further, as a circuit for generating an output of each phase of the three-phase alternating current to be output to the motor generator, a power conversion device having a circuit configuration in which two upper and lower arm series circuits are connected in parallel to each phase may be used.

  FIG. 7 shows another embodiment in which a labyrinth seal is used as a seal structure for preventing a flow that bypasses between the partition wall 408 and the metal base 304 based on the power conversion device described in the first embodiment. Instead of using an O-ring, a labyrinth seal structure is used, and a labyrinth seal projection 306 is provided on a metal base and a labyrinth seal recess 802 is provided on the housing 12, and sealing is performed with the unevenness of both.

  By providing the concavo-convex portion, the distance for bypassing the partition wall is increased, and further, a portion where the direction of the bypass flow is bent at a right angle is formed, so that friction loss increases and the bypass flow 423 can be relaxed. This structure is characterized in that the shape of the O-ring 800 can be simplified as compared with the first embodiment.

  An embodiment in the case where the fins attached to the metal base 304 are used in combination with not only the pin fins 305a but also the flat plate fins 305b will be described.

  FIG. 8 shows the refrigerant flow in the U-turn portion when the pin fins 305a and the flat fins 305b are combined. The portion of the pin fin 305a is narrowed locally by narrowing the portion of the pin fin 305a that is about to enter the U-turn portion, that is, the end portion where the first passage 19a and the second passage 19b are completely separated by the partition 408. Instead, a flat fin 305b is used.

  The flow path width 307 of the flat fin portion can be cooled including the spread of heat by adjusting the width of the IGBTs 328/330 and the diodes 156/166 and the thickness of the metal base 304.

  The reason why the flow path width 307a of the flat plate fin portion needs to be smaller than the flow width 307b of the pin fin portion is that the flat plate fin has a property of lower heat transfer coefficient and pressure loss than the pin fin, This is because the flow velocity between the flat fins needs to be about twice the flow velocity between the pin fins. Compared with the first embodiment, the U-turn upstream vector 421a can be forcibly guided in the direction of the semiconductor element, so that a larger cooling performance than that of the first embodiment can be obtained.

  FIG. 9 shows another embodiment in which the cooling performance of the U-turn portion is promoted by changing the shape of the end portion of the partition wall based on the power conversion device described in the first embodiment. By increasing the tip of the partition wall 408, the vectors 421a / 421b of the U-turn upstream portion and the U-turn downstream portion have components in the direction toward the corner portion, so that cooling can be promoted even in a portion where liquid easily stagnates. . Compared to the first embodiment, the U-turn upstream portion and the U-turn downstream portion vector 421a / 421b can be forcibly guided in the direction of the semiconductor element, so that a larger cooling performance than that of the first embodiment can be obtained.

  FIG. 10 shows another embodiment in which the shape of the end portion of the partition wall is asymmetrical and the cooling performance of the U-turn portion is promoted based on the power conversion device described in the first embodiment. By bending the end 424 of the partition wall in the direction toward the corner on the upstream side of the flow, the vectors 421a / 421b of the U-turn upstream part and the U-turn downstream part have components in the direction toward the corner part. Cooling can be promoted even at sites where the liquid tends to stagnate.

  This embodiment is particularly suitable when the cooling water inlet pipe 13 and the cooling water outlet pipe 14 are uniquely determined and the inlet and the outlet are not reversed and are not used, and when no water leakage occurs even with four water channel cover fixing screws 414. Is preferred. Compared to the first embodiment, the U-turn upstream vector 421a can be forcibly guided in the direction of the semiconductor element, and the U-turn downstream portion is cooled using centrifugal force. Therefore, the U-turn portion is improved while improving the cooling performance. Pressure loss can be reduced.

It is an appearance perspective view of the whole composition of the power converter concerning the embodiment of the present invention. It is the perspective view which decomposed | disassembled the whole structure of the power converter device which concerns on embodiment of this invention into each component. It is a figure which shows the housing | casing regarding embodiment of this invention, and the cooling water flow in a cooling water flow path. It is the top view which looked at the housing | casing which mounted the power module regarding this embodiment from the downward direction. It is sectional drawing when the whole structure of the power converter device shown in FIG.1 and FIG.2 regarding this embodiment is cut | disconnected. It is the figure which showed the relative positional relationship of the flow path U-turn part shape, semiconductor element, and fin layout regarding this embodiment. It is a figure which shows a labyrinth seal structure in the seal structure for bypass flow prevention. It is a figure showing the flow of the refrigerant | coolant of a U-turn part at the time of combining a pin fin and a flat fin. It is the figure which enlarged the width | variety simultaneously with denting the terminal part of a partition. It is a figure at the time of bending the terminal part shape in the direction of the corner part of the upstream of the flow at the terminal part of the partition. (A) is an upper perspective view of the power module 300 according to the present embodiment, and (b) is a top view of the power module 300. It is a disassembled perspective view of the DC terminal of the power module 300 regarding this embodiment. In order to make the structure of the DC bus bar easy to understand, the power module case 302 is a sectional view partially transparent. It is a figure which shows the control block of a hybrid vehicle. It is a figure which shows the electric circuit structure of the apparatuses 140 and 142 or the inverter apparatus 43. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Upper case 11 Metal base board 12 Case 13 Cooling water inlet piping 14 Cooling water outlet piping 16 Lower case 17 AC wiring case 18 AC wiring 19 Cooling water flow path 19a First flow path 19b Second flow path 20 Control circuit board 21 Connector 22 Drive circuit board 23 Inter-board connector 43 Inverter device (for auxiliary equipment including power module)
140, 142 Inverter 144 Inverter circuit 156 Upper arm diode 159 AC terminal 166 Lower arm diode 169 Intermediate electrode 172 Control circuit 174 Driver circuit 186 AC power line 188 AC connector 192, 194 Motor generator 195 Motor (auxiliary = air conditioner, Oil pump, cooling pump)
200 Power converter 300 Power module (semiconductor module)
304 Metal base 305 Fin 305a Pin fin 305b Flat fin 306 Projection for labyrinth seal 307a Flow path width 307b for flat fin portion Channel width 314 for pin fin portion DC positive bus bar 316 DC negative bus bar 318, 704 Insulating paper 328 IGBT for upper arm
330 IGBT for lower arm
400, 402, 404 Opening 406 Through hole 408 Bulkhead 410 Support part 412, 414 Screw hole (for power module fixing)
416 Screw hole (for fixing the water channel cover)
418 Flow of refrigerant (inflow direction)
420 Cover 421 Flow of refrigerant (U-turn part)
421a U-turn upstream vector 421b U-turn downstream vector 422 Refrigerant flow (outflow direction)
423 Refrigerant flow (bypass flow direction in midway)
424 Bulkhead end (U-turn)
500 Capacitor Module 502 Capacitor Case 504 Positive Side Capacitor Terminal 505 Negative Electrode Plate 506 Negative Side Capacitor Terminal 507 Positive Conductor Plate 510 Direct Current (Battery) Negative Side Connection Terminal 512 Direct Current (Battery) Positive Side Connection Terminal 514 Capacitor Cell 532 Auxiliary Equipment Positive electrode terminal 534 Auxiliary negative electrode terminal 700 Multilayer conductor plate 702 Positive electrode bus bar 706 Negative electrode bus bar 800 O-ring 801 O-ring groove 801a O-ring groove 801b of power module 1 O-ring groove 802 of labyrinth seal

Claims (8)

A flow path forming body having a first flow path and a second flow path through which a fluid cooling medium flows, and wherein the first flow path and the second flow path are formed in parallel;
A power conversion device comprising a plurality of semiconductor chips for converting DC power to AC power and a metal heat dissipating plate mounted with a connection conductor plate for supplying DC power to the semiconductor chips,
The first flow path and the second flow path are each provided with an opening, and the opening is closed by the metal heat sink,
The plurality of semiconductor chips are separately arranged so as to face the first flow path and the second flow path via the metal heat sink,
The power converter according to claim 1, wherein the connection conductor plate is disposed so as to be opposed to the first flow path and the second flow path via the metal heat sink. The power conversion device according to claim 1,
The said metal heat sink is a power converter device arrange | positioned so that the opening provided in the said 1st flow path and the said 2nd flow path may be plugged over the said 1st flow path and the said 2nd flow path. The power conversion device according to claim 1,
A partition partitioning the first flow path and the second flow path;
A turn portion provided in the vicinity of an end of the partition wall and connecting the first flow path and the second flow path;
A fin provided on the heat sink made of metal and projecting into the flow path of the flow path forming body from the opening,
The tip of the region where the fin is provided is a power conversion device provided closer to the turn portion than the end of the partition. The power conversion device according to claim 1,
A partition partitioning the first flow path and the second flow path;
A non-metallic sealing material provided between the partition and the metal heat sink. The power conversion device according to claim 1,
A partition partitioning the first flow path and the second flow path;
A turn portion provided in the vicinity of an end of the partition wall and connecting the first flow path and the second flow path;
Provided in the vicinity of the tip of the partition wall, and a protruding portion protruding toward the first flow path or the second flow path,
The power converter which changes the flow direction of the cooling water which flows in the said 1st flow path or the said 2nd flow path. The power conversion device according to claim 1,
A partition partitioning the first flow path and the second flow path;
A power converter comprising: the partition wall and the metal heat radiating plate including an uneven portion having a sealing function between the first channel and the second channel by fitting. The power conversion device according to claim 1,
A partition partitioning the first flow path and the second flow path;
A turn portion provided in the vicinity of an end of the partition wall and connecting the first flow path and the second flow path;
A power converter comprising: a recess provided at a tip portion of the partition wall and having a curvature opposite to the curvature of the turn portion. The power conversion device according to claim 1,
The width of the flow path is locally narrowed in either the first flow path or the second flow path, or both,
Furthermore, the power converter device which equips the site | part formed narrow locally with a flat fin.

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