JP2018166371A - Inverter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inverter device capable of reducing the thermal interference between switching element units even when two switching element units are arranged in close proximity.SOLUTION: An inverter device includes a heat sink 3 having a first face F1 on which a first switching element unit 20Q and a second switching element unit 20R are arranged side by side, and a second face F2 opposite the first face F1 and on which a plurality of radiation fins 33 are disposed. The heat sink 3, viewed from the facing direction Z being orthogonal to the first face F1, has a thin wall part 4 disposed in an intermediate region 31M between a first arrangement region 31Q in which the first switching element unit 20Q is arranged and a second arrangement region 31R in which the second switching element unit 20R is arranged, whose wall thickness between the first face F1 and second face F2 is thinner than both the first arrangement region 31Q and the second arrangement region 31R.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an inverter device including two switching element units.

  For example, in the following Patent Document 1 (Japanese Patent Laid-Open No. 2015-89245), two switching element units (inverters 13) formed by combining a plurality of switching elements are arranged inside one housing (12). An inverter device (10) arranged in is disclosed. In the inverter device (10) of Patent Document 1, the overall size of the device is reduced as compared with the case where the two switching element units (13) are individually arranged by such a configuration.

JP2015-89245A

  By the way, in the inverter device (10) of Patent Document 1, a capacitor (15) for suppressing overvoltage of the switching element between the two switching element units (13) in the arrangement direction of the two switching element units (13). ) Is arranged. Therefore, if the arrangement position of the capacitor (15) is moved from between the two switching element units (13) to another place, the two switching element units can be arranged close to each other. The device can be further reduced in size in the arrangement direction of the element units (13).

  However, this has the following problems. That is, since the two switching element units are arranged close to each other, when one switching element unit generates heat, this heat is transmitted to the other switching element unit through the housing, and the two switching element units Thermal interference may occur between units. For example, when each switching element unit includes a temperature sensor such as a thermistor, such thermal interference may cause erroneous detection of the temperature sensor or cause malfunction of a control device that controls each switching element. May be.

  Therefore, even when two switching element units are arranged close to each other, it is desired to realize an inverter device that can reduce thermal interference between the switching element units.

The inverter device according to the present disclosure is:
A first switching element unit including a plurality of switching elements constituting the first inverter circuit;
A second switching element unit including a plurality of switching elements constituting the second inverter circuit;
A first surface on which the first switching element unit and the second switching element unit are arranged side by side; a second surface on the opposite side of the first surface and provided with a plurality of heat radiation fins; A heat sink having,
The heat sink is between a first arrangement area where the first switching element unit is arranged and a second arrangement area where the second switching element unit is arranged when viewed from a facing direction perpendicular to the first surface. The intermediate region has a thin portion between the first surface and the second surface that is thinner than both the first and second arrangement regions.

  According to this configuration, the thickness of the heat sink can be reduced in at least a part of the intermediate region by the thin portion. Therefore, it is possible to reduce the cross-sectional area of at least part of the path through which heat is conducted between the first switching element unit and the second switching element unit. Thereby, the heat conduction which passes along the thin part between a 1st switching element unit and a 2nd switching element unit can be restrict | limited, and it can make it easy to conduct heat to another part. Accordingly, it is possible to reduce thermal interference between the switching element units as compared with a case where such a thin portion is not provided.

  Further features and advantages of the technology according to the present disclosure will become more apparent from the following description of exemplary and non-limiting embodiments described with reference to the drawings.

The schematic circuit diagram of an inverter apparatus. The top view which shows typically the arrangement | positioning relationship of each part of an inverter apparatus. Sectional drawing of an inverter apparatus. The principal part enlarged view of FIG. The top view which shows the case and switching element unit of an inverter apparatus. The principal part enlarged view of FIG. The principal part expanded sectional view of the inverter apparatus which concerns on other embodiment. The principal part expanded sectional view of the inverter apparatus which concerns on other embodiment. The principal part expanded sectional view of the inverter apparatus which concerns on other embodiment. The principal part expanded sectional view of the inverter apparatus which concerns on other embodiment. Sectional drawing of the inverter apparatus which concerns on a comparative example. The principal part enlarged view of FIG.

1. First Embodiment An inverter device 1 according to a first embodiment will be described with reference to the drawings. Below, the case where the inverter apparatus 1 is applied to the rotary electric machine drive device which drives two rotary electric machines is demonstrated to an example with reference to drawings.

1-1. Circuit Configuration As shown in FIG. 1, the inverter device 1 includes a first inverter unit 2Q that drives the first rotating electrical machine 8Q and a second inverter unit 2R that drives the second rotating electrical machine 8R. In the present embodiment, one inverter control unit CU controls both the first inverter circuit 21Q included in the first inverter unit 2Q and the second inverter circuit 21R included in the second inverter unit 2R. However, the inverter circuits 21Q and 21R may be individually controlled by two inverter control devices.

  As described above, the inverter device 1 includes the first switching element unit 20Q including the plurality of switching elements 21 constituting the first inverter circuit 21Q and the plurality of switching elements 21 constituting the second inverter circuit 21R. 2 switching element unit 20R. Each inverter circuit 21Q, 21R converts power between DC power and a plurality of phases of AC power.

  FIG. 1 shows a first inverter circuit 21Q that is connected to an AC first rotating electrical machine 8Q and a DC power source 9 and converts electric power between a plurality of phases of AC and DC, an AC second rotating electrical machine 8R, and A second inverter circuit 21R that is connected to the DC power source 9 and converts power between a plurality of phases of AC and DC is illustrated. In the present embodiment, the DC power supply 9 is a battery. Note that another power storage device such as a capacitor may be used as the DC power source 9.

  A first capacitor 6Q (DC link capacitor) for smoothing the voltage on the DC side of the first inverter circuit 21Q is provided on the DC side of the first inverter circuit 21Q. Further, a second capacitor 6R (DC link capacitor) for smoothing the voltage on the DC side of the second inverter circuit 21R is provided on the DC side of the second inverter circuit 21R.

  The first rotating electrical machine 8Q and the second rotating electrical machine 8R can be used as a driving force source for wheels in a vehicle such as a hybrid vehicle or an electric vehicle. In addition, since the inverter device 1 according to the present embodiment has a configuration in which a pair of inverter units 2Q and 2R are arranged in parallel in the case 5, for example, a pair of left and right wheels in a vehicle are each paired with a pair of rotating electrical machines 8Q and 8R. Is particularly suitable for an inverter device for driving the pair of rotating electrical machines 8Q and 8R. Here, the first rotating electrical machine 8Q and the second rotating electrical machine 8R can function as both an electric motor and a generator. The first rotating electrical machine 8Q converts the electric power supplied from the DC power supply 9 through the first inverter circuit 21Q into power for driving the wheels (power running). Alternatively, the first rotating electrical machine 8Q converts the rotational driving force transmitted from the internal combustion engine and the wheels into electric power, and charges the DC power supply 9 via the first inverter circuit 21Q (regeneration). Such power running and regeneration operations can be performed in the same manner by the second rotating electrical machine 8R.

  In the present embodiment, the first inverter unit 2Q and the second inverter unit 2R have the same circuit configuration. Hereinafter, the first inverter unit 2Q will be described, and the second inverter unit 2R will be described as necessary.

  The first inverter circuit 21Q converts the DC power of the DC power source 9 into a plurality of phases (here, three phases) of AC power and supplies the AC power to the first rotating electrical machine 8Q, and the AC power generated by the first rotating electrical machine 8Q. Is converted to DC power and supplied to the DC power source 9.

  The first inverter circuit 21Q includes a plurality of switching elements 21. In the example shown in FIG. 1, the switching element 21 is configured by an IGBT (Insulated Gate Bipolar Transistor). However, the switching element 21 is not limited to the IGBT, but as a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), SiC-MOSFET (Silicon Carbide-Metal Oxide Semiconductor FET), SiC-SIT (SiC-Static Induction Transistor), GaN-MOSFET. Various power semiconductor elements such as (Gallium Nitride-MOSFET) can be applied.

  As shown in FIG. 1, the first inverter circuit 21 </ b> Q is configured by a bridge circuit having a number (here, three) of arms 21 </ b> A corresponding to each of a plurality of phases of AC power. In the case of the three-phase first rotating electrical machine 8Q, a bridge circuit is configured in which a set of series circuits (arms 21A) corresponds to the stator coils 81 corresponding to the U phase, the V phase, and the W phase. Each arm 21A is configured by a series circuit of an upper stage switching element 21H and a lower stage switching element 21L. The intermediate point of each arm 21A, that is, the connection point between the switching element 21 on the positive electrode P side of the DC power supply 9 (upper stage switching element 21H) and the switching element 21 on the negative electrode N side of the DC power supply 9 (lower switching element 21L). Are respectively connected to the three-phase stator coils 81 of the first rotating electrical machine 8Q. Each switching element 21 is provided with a free wheel diode 21D in parallel with the direction from the negative electrode “N” of the DC power source 9 to the positive electrode “P” (the direction from the lower side to the upper side) as the forward direction. Yes.

  In the present embodiment, the switching element 21 constituting the arm 21A for three phases including the free wheel diode 21D is integrated into one power module to constitute the first switching element unit 20Q. Similarly, a second switching element unit 20R is configured for the second inverter unit 2R.

  As shown in FIG. 1, the first inverter circuit 21Q is controlled by the inverter control unit CU. The actual current flowing through the stator coil 81 of each phase of the first rotating electrical machine 8Q is detected by the current sensor 82, and the inverter control unit CU acquires the detection result. Further, the magnetic pole position at each time point of the rotor of the first rotating electrical machine 8Q is detected by a rotation sensor 83 such as a resolver, for example, and the inverter control unit CU acquires the detection result. The inverter control unit CU performs current feedback control using detection results of the current sensor 82 and the rotation sensor 83, and controls the first rotating electrical machine 8Q via the first inverter circuit 21Q. As described above, in the present embodiment, one inverter control unit CU controls both the first rotating electrical machine 8Q and the second rotating electrical machine 8R via the first inverter circuit 21Q and the second inverter circuit 21R. To do. The control of the second rotating electrical machine 8R via the second inverter circuit 21R is the same as that of the first inverter circuit 21Q and the first rotating electrical machine 8Q.

1-2. Mechanical Configuration of Inverter Device As shown in FIG. 2, the first switching element unit 20 </ b> Q and the second switching element unit 20 </ b> R are accommodated in the case 5. In the present embodiment, in addition to these, the inverter controller CU that controls the first capacitor 6Q and the second capacitor 6R, and the first inverter circuit 21Q and the second inverter circuit 21R (see FIG. 1) is provided inside the case 5. Is housed in. Here, the inverter control unit CU is a control board.

  As shown in FIG. 2, the first switching element unit 20 </ b> Q and the first capacitor 6 </ b> Q are electrically connected within the case 5. The first switching element unit 20Q is electrically connected to the first rotating electrical machine 8Q outside the case 5, and the first capacitor 6Q is electrically connected to the DC power source 9 outside the case 5.

  Similarly, the second switching element unit 20R and the second capacitor 6R are also electrically connected within the case 5. The second switching element unit 20R is electrically connected to the second rotating electrical machine 8R outside the case 5, and the second capacitor 6R is electrically connected to the DC power source 9 outside the case 5.

  As described above, in the present embodiment, the first inverter unit 2Q including the first capacitor 6Q and the first switching element unit 20Q, the second capacitor 6R, and the second switching element unit 20R are configured. The second inverter unit 2 </ b> R having the same configuration is arranged in parallel in the case 5. In the following, the first switching element unit 20Q and the second switching element unit are viewed in a plan view shown in FIG. 2, that is, when viewed from the facing direction Z perpendicular to the first surface F1 of the heat sink 3 serving as an element arrangement surface of the case 5 described later. A direction in which 20R is arranged will be referred to as an arrangement direction X, and a direction orthogonal to the arrangement direction X will be described as an arrangement orthogonal direction Y.

  The first inverter unit 2Q includes a direct current side terminal 61, a first capacitor 6Q, a connection terminal 22D, a first switching element unit 20Q, and an alternating current side terminal 22A. It is arranged in the order of description toward the side. Here, the DC side terminals 61 are a pair of terminals that are electrically connected to the positive electrode P and the negative electrode N of the DC power supply 9. The connection terminal 22D is a positive / negative two-pole DC terminal that electrically connects the first capacitor 6Q and the first switching element unit 20Q. The AC side terminal 22A is an AC terminal that is electrically connected to each phase (three-phase) stator coil 81 of the first rotating electrical machine 8Q.

  Similarly, the second inverter unit 2R includes a DC side terminal 61, a second capacitor 6R, a connection terminal 22D, a second switching element unit 20R, and an AC side terminal 22A. From the side toward the other side in the order of description. The first inverter unit 2Q and the second inverter unit 2R are arranged in parallel in the case 5 so as to be arranged in the arrangement direction X. Also, the DC side terminals 61 of both the first inverter unit 2Q and the second inverter unit 2R are arranged along one side in the arrangement orthogonal direction Y of the case 5, and the first inverter unit 2Q and the second inverter unit Both 2R AC side terminals 22 </ b> A are arranged along the other side of the case 5 in the direction orthogonal to the array Y. By arranging the DC side terminal 61 and the AC side terminal 22A in this way, wiring for connecting the inverter device 1 to the DC power source 9 and the two rotating electrical machines 8Q and 8R can be easily performed. Yes.

  In the present embodiment, as shown in FIG. 3, the first switching element unit 20Q and the second switching element unit 20R are adjacent to each other in the arrangement direction X in which they are arranged, and are arranged close to each other. Yes. Thereby, it is possible to reduce the size of the inverter device 1 in the arrangement direction X.

  Here, the switching element units 20Q and 20R are likely to generate a large amount of heat when a large current for driving the rotating electrical machines 8Q and 8R flows or when they are turned on and off at high speed. Therefore, as shown in FIG. 3, the inverter device 1 includes a first surface F1 in which the first switching element unit 20Q and the second switching element unit 20R are arranged side by side, and a side opposite to the first surface F1. And a heat sink 3 having a second surface F2 provided with a plurality of heat radiation fins 33. Thereby, the generated switching element 21 can be cooled. In FIG. 3, only the case 5, the heat sink 3, and the switching element units 20Q and 20R are shown for ease of explanation.

  In the present embodiment, the heat sink 3 is integrated with the case 5. In the example illustrated in FIG. 3, the first surface F <b> 1 is disposed inside the case 5, and the second surface F <b> 2 is disposed outside the case 5. The first surface F1 is an arrangement surface of the switching element units 20Q and 20R formed on the element arrangement surface on which the capacitors 6Q and 6R, the switching element units 20Q and 20R, etc. are arranged on the inner surface 51F of the case 5. . For this reason, the first surface F1 is a plane along both the arrangement direction X and the arrangement orthogonal direction Y. On the other hand, the second surface F2 is a surface on the opposite side of the heat sink 3 from the first surface F1 and provided with the radiation fins 33. Here, it is possible to define the second surface F2 as a plane that does not include the protruding portion due to the heat radiating fins 33, but in this example, the second surface F2 is defined as all surfaces including the unevenness of the radiating fins 33. To do.

  In the present embodiment, the first surface F1 is formed on the inner side surface (upper surface in FIG. 3) of the trapezoidal portion protruding inward (upper side in FIG. 3) on the inner surface 51F of the case 5. Therefore, the thickness of the heat sink 3 in the facing direction Z perpendicular to the first surface F1 is thicker in the region where the first surface F1 is formed than in other regions of the inner surface 51F of the case 5. As a result, it is possible to secure a large heat capacity of the heat sink 3 in the region where the first surface F1 is provided, and to mitigate local and sudden temperature rise when the switching element 21 generates heat. Yes.

  As shown in FIGS. 3 to 6, when viewed from the facing direction Z, the heat sink 3 includes a first arrangement region 31Q in which the first switching element unit 20Q is arranged and a second arrangement in which the second switching element unit 20R is arranged. It has an arrangement area 31R, and an intermediate area 31M located between the first arrangement area 31Q and the second arrangement area 31R. In the present embodiment, the first arrangement region 31Q and the second arrangement region 31R are formed on the first surface F1 and are aligned with each other in the arrangement direction X.

  As shown in FIG. 3, the plurality of heat radiation fins 33 are arranged in the arrangement direction X on the second surface F <b> 2. Each of the plurality of radiating fins 33 has a shape extending along the array orthogonal direction Y, which is a direction orthogonal to the array direction X of the first arrangement region 31Q and the second arrangement region 31R. In addition, a plurality of fin bottom groove portions 35 that are groove-like portions sandwiched between two adjacent radiating fins 33 are formed side by side in the arrangement direction X on the second surface F2. Therefore, each of the plurality of fin bottom groove portions 35 also has a shape extending along the array orthogonal direction Y. Then, the refrigerant flows along the radiation fins 33, and the heat generated by the switching elements 21 and the like is radiated from the radiation fins 33. The refrigerant may be a gas or a liquid. In the present embodiment, the fin bottom groove portion 35 corresponds to a “bottom groove portion” of the radiation fin 33.

  Here, each switching element unit 20Q, 20R is provided with a temperature sensor (not shown) such as a thermistor for detecting the temperature of each switching element 21. When the temperature sensor detects that the switching element 21 or the switching element unit 20 is at a temperature higher than the threshold value, this detection information is transmitted to the inverter control unit CU. In the inverter control unit CU, in order to protect the switching element 21 by suppressing the temperature rise of the switching element 21 or the switching element unit 20, protection such as turning off all the switching elements 21 of the inverter circuits 21Q and 21R. Control is executed.

  By the way, when such protection control is executed, the inverter device 1 can be protected, but since the rotating electrical machines 8Q and 8R that are normal cannot be driven, such protection control is really necessary. It should only be executed when However, as described above, when the first switching element unit 20Q and the second switching element unit 20R are arranged close to each other, due to the influence of heat generated by one, the other temperature sensor is actually more However, there is a possibility that protection control is executed even though it is not actually necessary. The inverter device 1 according to the present embodiment includes a first arrangement region 31Q in which the first switching element unit 20Q is arranged, and a second switching element unit in order to reduce the possibility of such so-called thermal interference. A thin portion 4 is provided in an intermediate region 31M between the second placement region 31R where 20R is placed and the heat conduction between the first switching device unit 20Q and the second switching device unit 20R is limited. ing.

  11 and 12 show a comparative example that does not include such a thin portion 4. In the inverter device 100 of this comparative example, the first arrangement region 301Q in which the first switching element unit 20Q is arranged, the second arrangement region 301R in which the second switching element unit 20R is arranged, and the first arrangement region 301Q, The thickness of the heat sink 3 is uniform over the entire intermediate region 301M located between the second arrangement region 301R. Therefore, for example, as shown in FIG. 12, the heat generated from the switching element 21 of the first switching element unit 20Q is transmitted through the intermediate region 301M without being particularly limited, and reaches the second switching element unit 20R. That is, the intermediate region 301M between the first switching element unit 20Q and the second switching element unit 20R in the heat sink 300 serves as a heat conduction path 99 to conduct heat. For this reason, there is a high possibility that so-called thermal interference in which the heat generated by one of the first switching element unit 20Q and the second switching element unit 20R affects the detection value of the other temperature sensor occurs.

  Therefore, in the inverter device 1 according to the present embodiment, as illustrated in FIGS. 3 to 6, the heat sink 3 includes the first arrangement region 31 </ b> Q in which the first switching element unit 20 </ b> Q is arranged when viewed from the facing direction Z, In the intermediate region 31M between the second placement region 31R in which the second switching element unit 20R is placed, the first surface F1 and the second surface are compared to both the first placement region 31Q and the second placement region 31R. It has the thin part 4 with a thin wall thickness between F2. Thereby, the cross-sectional area of at least a part of the heat conduction path 99 between the first switching element unit 20Q and the second switching element unit 20R can be reduced. Therefore, heat conduction through the thin portion 4 between the first switching element unit 20Q and the second switching element unit 20R can be limited, and heat can be easily conducted to other parts. Accordingly, it is possible to reduce thermal interference between the switching element units 20Q and 20R as compared with the case where the thin portion 4 is not provided.

  As shown in FIG. 5, the first arrangement region 31Q is a region overlapping the first switching element unit 20Q when viewed from the facing direction Z on the first surface F1. More specifically, the first arrangement region 31Q is surrounded by the first unit front wall 24Q, the first unit rear wall 25Q, and the pair of first unit side walls 23Q and 23Q of the first switching element unit 20Q. Area.

  Further, the second arrangement region 31R is a region overlapping the second switching element unit 20R when viewed from the facing direction Z on the first surface F1. More specifically, the second arrangement region 31R is surrounded by the second unit front wall 24R, the second unit rear wall 25R, and the pair of second unit side walls 23R and 23R of the second switching element unit 20R. Area.

  The intermediate region 31M is a region sandwiched between the first arrangement region 31Q in which the first switching element unit 20Q is arranged and the second arrangement region 31R in which the second switching element unit 20R is arranged. Therefore, in the present embodiment, the intermediate region 31M is a region sandwiched between the first unit side wall 23Q and the second unit side wall 23R facing each other. That is, as can be seen with reference to FIG. 5, in this example, the length of the intermediate region 31M in the arrangement orthogonal direction Y is determined by the first unit front wall 24Q (second unit front wall 24R) and the first unit rear wall. 25Q (second unit rear wall 25R) and the length between them.

  As shown in FIGS. 3 to 6, in this embodiment, the thin-walled portion 4 has a groove shape that opens in the first surface F <b> 1, is recessed toward the second surface F <b> 2, and extends along the array orthogonal direction Y. It is formed by the concave groove portion 7. That is, as shown in FIGS. 3 and 4, the thin-walled portion 4 is formed in a region overlapping the concave groove portion 7 when viewed from the facing direction Z. As described above, the thin portion 4 according to the present embodiment is formed by processing a part of the first surface F1 opposite to the second surface F2 provided with the plurality of heat radiation fins 33 into a groove shape. Has been. Moreover, since the thin part 4 can be made into a shape long in the arrangement orthogonal direction Y along the concave groove part 7, the heat conduction between the first switching element unit 20Q and the second switching element unit 20R by the thin part 4 The effect which suppresses is made high.

  In the example shown in FIG. 4, the concave groove portion 7 is formed with a constant width in the arrangement direction X. Further, the groove portion 7 includes a pair of groove wall portions 71 facing each other and facing the arrangement direction X, and a groove groove bottom portion 72 that connects ends of the pair of groove wall walls 71 on the second surface F2 side, have. The thin portion 4 is formed between the groove bottom portion 72 and the second surface F2 in the facing direction Z. The width in the arrangement direction X of the concave grooves 7 may be different depending on the position in the arrangement orthogonal direction Y.

  As shown in FIG. 5, in the present embodiment, the thin portion 4 is formed in the entire region sandwiched between the first arrangement region 31Q and the second arrangement region 31R in the array orthogonal direction Y. That is, the thin portion 4 is formed in the entire intermediate region 31M in the array orthogonal direction Y. Thereby, the heat conduction between the first switching element unit 20Q and the second switching element unit 20R over the entire region sandwiched between the first arrangement region 31Q and the second arrangement region 31R in the arrangement orthogonal direction Y. The effect which suppresses can be acquired. However, the thin portion 4 may be formed only in a part of a region sandwiched between the first arrangement region 31Q and the second arrangement region 31R in the arrangement orthogonal direction Y. Even in this case, the effect of suppressing heat conduction between the first switching element unit 20Q and the second switching element unit 20R can be obtained within the range where the thin portion 4 is formed.

  Moreover, in this embodiment, as shown in FIG. 4, the fin bottom groove part 35 arrange | positioned in the position which overlaps with the concave groove part 7 seeing from the facing direction Z among several fin bottom groove parts 35 is made into object bottom groove part 35S. When viewed from the facing direction Z, the entire target bottom groove portion 35S is disposed so as to be included in the region where the concave groove portion 7 is formed. Here, the width W3 of the fin bottom groove portion 35 in the arrangement direction X is equal to or smaller than the width W1 of the concave groove portion 7. Thereby, the uneven | corrugated shape of the groove part 7 and the radiation fin 33 can be utilized effectively, and the width | variety of the arrangement direction X of the thin part 4 can be ensured easily. In the example shown in FIG. 4, the thickness L1 of the thin portion 4 in the region overlapping the target bottom groove portion 35S when viewed from the facing direction Z is equal to the distance between the concave groove bottom portion 72 and the target bottom groove portion 35S.

  In the example shown in FIG. 4, the width W3 of the target bottom groove 35S in the arrangement direction X is smaller than the width W1 of the concave groove bottom 72. However, the width W1 of the groove bottom 72 and the width W3 of the target bottom groove 35S may be the same.

  Further, in the present embodiment, as shown in FIG. 4, when viewed from the facing direction Z, the thickness L1 of the thin portion 4 in the region overlapping the target bottom groove portion 35S is larger than the width W2 of the radiating fins 33 in the arrangement direction X. small. Thereby, the heat conduction through the thin portion 4 between the first switching element unit 20Q and the second switching element unit 20R is limited, and heat is easily conducted to the radiation fin 33 having a width W2 wider than the thin portion 4. It has become.

  As described above, according to the inverter device 1 according to the present embodiment, the heat conduction through the thin portion 4 between the first switching element unit 20Q and the second switching element unit 20R is limited, and other parts are used. Heat can be easily conducted. Accordingly, it is possible to reduce the thermal interference between the switching element units 20Q and 20R as compared with the case where the thin portion 4 is not provided.

2. Other Embodiments Next, other embodiments of the inverter device will be described.

(1) In the above-described embodiment, the example in which the entire target bottom groove portion 35S is included in the region where the concave groove portion 7 is formed when viewed from the facing direction Z has been described. However, the present invention is not limited to such an example. As shown in FIG. 7, a part of the plurality of fin bottom groove portions 35 and the concave groove portions 7 may be arranged at positions overlapping each other when viewed from the facing direction Z. In the example shown in FIG. 7, each of the two fin bottom groove portions 35 partially overlaps the concave groove portion 7 when viewed from the facing direction Z. In this case, the two fin bottom groove portions 35 are the target bottom groove portions 35S.

(2) In the above-described embodiment, the example in which the recessed groove portion 7 that forms the thin portion 4 opens to the first surface F1 and is recessed toward the second surface F2 has been described. However, the present invention is not limited to such an example. As shown in FIG. 8, the recessed groove portion 7 may be formed so as to open to the second surface F2 and to be recessed toward the first surface F1. In the example shown in FIG. 8, the recessed groove portion 7 is formed integrally with a part of the fin bottom groove portion 35, and is formed to be recessed in the first surface F <b> 1 than the other fin bottom groove portion 35. In this case, the thin portion 4 is formed between the recessed groove portion 7 and the first surface F1 in the facing direction Z.

(3) In the above-described embodiment, the concave groove portion 7 forming the thin wall portion 4 is a concave portion connecting the pair of concave groove wall portions 71 and the ends of the pair of concave groove wall portions 71 on the second surface F2 side. The example formed in the shape of a concave groove having the groove bottom portion 72 has been described. However, the present invention is not limited to such an example. For example, as shown in FIG. 9, the recessed groove portion 7 may be formed in a U shape when viewed from the array orthogonal direction Y. In addition, as shown in FIG. 10, the groove portion 7 may be formed in a V shape when viewed from the array orthogonal direction Y. In any of these cases, the groove portion 7 is preferably in the shape of a groove that opens to either the first surface F1 or the second surface F2.

(4) In the above embodiment, an example in which the recessed groove portion 7 has a shape extending in the array orthogonal direction Y and thus the thin portion 4 is also formed in a region extending in the array orthogonal direction Y has been described. However, the present invention is not limited to such an example. The groove portion 7 only needs to be recessed from the first surface F1 or the second surface F2 in the intermediate region 31M, and the direction in which the groove portion 7 extends is not limited to a specific direction. Furthermore, the concave portion formed in the heat sink 3 for forming the thin portion 4 does not need to be formed in a groove shape.

(5) In the above embodiment, an example in which the circuit configuration of the first inverter unit 2Q and the second inverter unit 2R is the same has been described. However, for example, the circuit configuration such as the capacity and number of each element may be different between the first inverter unit 2Q and the second inverter unit 2R. For example, when the first inverter unit 2Q drives a rotating electrical machine for driving wheels of the vehicle, and the second inverter unit 2R drives an electric oil pump, an air conditioner, or the like included in the vehicle, the respective drives It is also suitable for different circuit configurations depending on the characteristics of the target, power consumption, and the like.

(6) It should be noted that the configurations disclosed in the above-described embodiments can be applied in combination with the configurations disclosed in other embodiments as long as no contradiction arises. Regarding other configurations, the embodiments disclosed herein are merely examples in all respects. Accordingly, various modifications can be made as appropriate without departing from the spirit of the present disclosure.

3. Outline of the above embodiment The outline of the above embodiment will be described below.

A first switching element unit (20Q) including a plurality of switching elements (21) constituting the first inverter circuit (21Q);
A second switching element unit (20R) including a plurality of switching elements (21) constituting the second inverter circuit (21R);
The first surface (F1) on which the first switching element unit (20Q) and the second switching element unit (20R) are arranged side by side is a surface opposite to the first surface (F1). A heat sink (3) having a second surface (F2) provided with a plurality of radiation fins (33),
The heat sink (3) includes a first arrangement region (31Q) in which the first switching element unit (20Q) is arranged, as viewed from a facing direction (Z) orthogonal to the first surface (F1), and the first Compared to both the first arrangement area (31Q) and the second arrangement area (31R) in the intermediate area (31M) between the second arrangement area (31R) where the two switching element units (20R) are arranged. The thin portion (4) having a small thickness between the first surface (F1) and the second surface (F2).

  According to this configuration, the thickness of the heat sink (3) can be reduced in at least a part of the intermediate region (31M) by the thin portion (4). Therefore, at least a part of the cross-sectional area in the path through which heat is conducted between the first switching element unit (20Q) and the second switching element unit (20R) can be reduced. Thereby, the heat conduction which passes along the thin part (4) between the 1st switching element unit (20Q) and the 2nd switching element unit (20R) can be restrict | limited, and it can make it easy to conduct heat to another part. . Therefore, it is possible to reduce thermal interference between the switching element units (20Q, 20R) as compared with the case where such a thin portion (4) is not provided.

  The thin portion (4) opens to the first surface (F1) and is recessed toward the second surface (F2), and includes the first arrangement region (31Q) and the second arrangement region (31R). It is preferable that the groove is formed by a groove-shaped groove portion (7) extending along the array orthogonal direction (Y), which is a direction orthogonal to the array direction (X).

  According to this configuration, a part of the first surface (F1) opposite to the second surface (F2) provided with the plurality of heat dissipating fins (33) is easily processed into a concave groove shape. A thin part (4) can be formed. Moreover, since the ditch | groove part (7) is extended along the sequence orthogonal direction (Y), a thin part (4) can be made into a shape long in the sequence orthogonal direction (Y). Therefore, the effect which suppresses the heat conduction between the 1st switching element unit (20Q) and the 2nd switching element unit (20R) by a thin part (4) can be heightened.

  The thin portion (4) is preferably formed in the entire region sandwiched between the first arrangement region (31Q) and the second arrangement region (31R) in the array orthogonal direction (Y). It is.

  According to this configuration, the first switching is performed by the thin portion (4) over the entire region sandwiched between the first arrangement region (31Q) and the second arrangement region (31R) in the arrangement orthogonal direction (Y). An effect of suppressing heat conduction between the element unit (20Q) and the second switching element unit (20R) can be obtained.

A plurality of the radiation fins (33) are arranged side by side in the arrangement direction (X), and each of the radiation fins (33) extends along the arrangement orthogonal direction (Y). ,
On the second surface (F2), a plurality of bottom groove portions (35) that are groove-like portions sandwiched between two adjacent heat radiating fins (33) are formed.
It is preferable that a part of the plurality of bottom groove portions (35) and the concave groove portion (7) are arranged at positions overlapping each other when viewed from the facing direction (Z).

  According to this structure, the thickness of the thin wall portion (4) can be easily formed thin by using the concave and convex portions of the concave groove portion (7) and the radiating fin (33).

Moreover, the said bottom groove part (35) arrange | positioned in the position which overlaps with the said recessed groove part (7) seeing from the said facing direction (Z) among several bottom groove parts (35) is made into an object bottom groove part (35S). ,
When viewed from the facing direction (Z), it is preferable that the entire target bottom groove portion (35S) is included in a region where the concave groove portion (7) is formed.

  According to this configuration, when the width of the bottom groove portion (35) in the arrangement direction (X) is equal to or smaller than the width of the concave groove portion (7), the concave and convex shapes of the concave groove portion (7) and the radiating fin (33) are effective. The width in the arrangement direction (X) of the thin wall portions (4) can be easily secured.

Moreover, the said bottom groove part (35) arrange | positioned in the position which overlaps with the front concave groove part (7) seeing from the said facing direction (Z) among several said bottom groove parts (35) is made into target bottom groove part (35S). ,
When viewed from the facing direction (Z), the thickness (L1) of the thin wall portion (4) in the region overlapping the target bottom groove portion (35S) is the width of the radiation fin (33) in the arrangement direction (X). It is preferable that it is smaller than (W2).

  According to this configuration, the heat conduction through the thin portion (4) between the first switching element unit (20Q) and the second switching element unit (20R) is limited, and the width ( Heat can be easily conducted to the heat dissipating fin (33) having a wide W2). Therefore, the thermal interference between the switching element units (20Q, 20R) can be further reduced.

  The technology according to the present disclosure can be used for an inverter device including two switching element units.

1: Inverter device 3: Heat sink 4: Thin part 7: Groove part 20Q: 1st switching element unit 20R: 2nd switching element unit 21: Switching element 21Q: 1st inverter circuit 21R: 2nd inverter circuit 31M: Intermediate Area 31Q: First arrangement area 31R: Second arrangement area 33: Radiation fin 35: Fin bottom groove (bottom groove)
35S: Target bottom groove portion F1: First surface F2: Second surface X: Array direction Y: Array orthogonal direction Z: Face-to-face direction

Claims (6)

A first switching element unit including a plurality of switching elements constituting the first inverter circuit;
A second switching element unit including a plurality of switching elements constituting the second inverter circuit;
A first surface on which the first switching element unit and the second switching element unit are arranged side by side; a second surface on the opposite side of the first surface and provided with a plurality of heat radiation fins; A heat sink having,
The heat sink is between a first arrangement area where the first switching element unit is arranged and a second arrangement area where the second switching element unit is arranged when viewed from a facing direction perpendicular to the first surface. An inverter device having a thin portion between the first surface and the second surface in the middle region of the first and second arrangement regions, as compared with both the first and second arrangement regions.   The thin-walled portion opens in the first surface and is recessed toward the second surface, and extends along an array orthogonal direction that is a direction orthogonal to the array direction of the first and second arrangement regions. The inverter device according to claim 1, wherein the inverter device is formed by a groove-shaped groove portion.   3. The inverter device according to claim 2, wherein the thin portion is formed over an entire region sandwiched between the first arrangement region and the second arrangement region in the array orthogonal direction. A plurality of the radiation fins are arranged side by side in the arrangement direction, and each of the radiation fins has a shape extending along the arrangement orthogonal direction,
A plurality of bottom groove portions that are groove-like portions sandwiched between two adjacent heat radiating fins are formed on the second surface,
4. The inverter device according to claim 2, wherein a part of the plurality of bottom groove portions and the concave groove portion are arranged at positions overlapping each other when viewed from the facing direction. Among the plurality of bottom groove portions, the bottom groove portion arranged at a position overlapping with the concave groove portion when viewed from the facing direction, as a target bottom groove portion,
The inverter device according to claim 4, wherein the entire target bottom groove portion is included in a region where the concave groove portion is formed when viewed from the facing direction. Among the plurality of bottom groove portions, the bottom groove portion arranged at a position overlapping with the concave groove portion when viewed from the facing direction, as a target bottom groove portion,
6. The inverter device according to claim 4, wherein a thickness of the thin portion in a region overlapping with the target bottom groove portion is smaller than a width of the radiating fin in the arrangement direction when viewed from the facing direction.

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