JP7124530B2 - power converter - Google Patents

Description

The present invention relates to a power converter that converts a DC current into an AC current while transforming a voltage from a DC power supply.

An example of the power conversion device described above is disclosed in Patent Document 1, for example. In the power conversion device of Patent Literature 1, a laminated body obtained by laminating a plurality of semiconductor modules each sealing a semiconductor element and a cooling pipe is accommodated in a case. The laminate is fixed to the bottom surface of the case, and the power terminals (positive terminal, negative terminal, AC terminal) of each semiconductor module project from the side opposite to the fixed side. It is electrically connected to a capacitor, reactor, etc.

Japanese Patent No. 6119419

Here, there is an increasing demand for a power conversion device to be made low profile and small in order to improve mountability on a vehicle or the like. When a power conversion device is made low-profile or small-sized, the distance between components that generate heat during operation, such as semiconductor modules, capacitors, and reactors, is narrowed. As a result, there arises a problem that the heat-generating components become susceptible to heat generation (thermal interference), making it difficult to sufficiently dissipate heat.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is an object of the present invention to provide a power conversion device capable of suppressing heat interference between heat-generating components even when the power conversion device is made low-profile and small-sized. aim.

In order to achieve the above object, a power conversion device (5) according to the present invention converts a DC current to an AC current while transforming a voltage from a DC power supply,
a case (100) that houses a plurality of electrical components that make up the power conversion device;
a cooling mechanism for cooling a plurality of heat-generating components (102, 110, 120) that generate heat during operation among the plurality of electrical components,
Among the plurality of heat-generating components, at least the first heat-generating component (110) and the second heat-generating component (120) are arranged in the case along a direction orthogonal to the depth direction of the case, and having power terminals (114, 130) protruding from the heat-generating component;
further comprising a bus bar (136) connecting power terminals of the first and second heat generating components;
The portion where the power terminal of the first heat-generating component protrudes and the portion where the power terminal of the second heat-generating component projects are provided on opposite sides of the center line in the depth direction of each heat-generating component. The direction of projection of the power terminal of the first heat-generating component is opposite to the direction of projection of the power terminal of the second heat-generating component.
The first heat-generating component is a semiconductor module in which a power terminal protrudes from a main body containing a power semiconductor element,
the second heat-generating component is a reactor,
The semiconductor module has control terminals protruding from a surface opposite to the surface from which the power terminals protrude,
The power terminal of the reactor has a cross section consisting of a long side and a short side, and the surface corresponding to the long side is joined to one end of the bus bar, and the surface corresponding to the short side is provided facing the control terminal of the semiconductor module. Characterized by

Thus, the power converter according to the present invention includes a cooling mechanism that cools a plurality of heat-generating components that generate heat during operation. Therefore, even if the first and second heat generating components generate heat during operation, the heat generation itself can be mitigated.

Although the first and second heat-generating components are cooled by the cooling mechanism as described above, this does not mean that they do not generate heat during operation. When heat is generated in one heat-generating component, the heat is transferred to the other heat-generating component through the power terminals and bus bars, which are easy to conduct heat. However, in the power converter according to the present invention, at least one of the power terminals of the first and second heat-generating components protrudes from a side other than the side facing each other, and the direction in which the power terminals of the first and second heat-generating components protrude is are provided differently. Therefore, even if the first and second heat generating components are arranged in the case along the direction perpendicular to the depth direction of the case, the power terminals of the first and second heat generating components can be connected. It is possible to increase the length of the busbar. As a result, heat transfer between the first and second heat generating components can be suppressed, and thermal interference can be suppressed.

Furthermore, in the power converter according to the present invention , the portion where the power terminal of the first heat generating component protrudes and the portion where the power terminal of the second heat generating component protrudes are located on the center line of each heat generating component in the depth direction. and the power terminals of the first heat-generating component and the power terminals of the second heat-generating component protrude in opposite directions. Therefore, local temperature rise inside the case due to radiant heat from each power terminal can be suppressed.

The reference numbers in parentheses above merely indicate an example of correspondence with specific configurations in the embodiments described later in order to facilitate the understanding of the present disclosure, and are not intended to limit the scope of the invention. It's not what I did.

In addition, technical features described in each claim of the scope of claims other than the features described above will become apparent from the description of the embodiments and the accompanying drawings, which will be described later.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of the drive system of the vehicle with which the power converter device which concerns on embodiment is applied. It is a cross-sectional view of a power converter. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2;

A power converter according to an embodiment of the present invention will be described below with reference to the drawings. The power converter according to this embodiment is applicable to vehicles such as electric vehicles (EV) and hybrid vehicles (HV). An example applied to a hybrid vehicle will be described below.

<Vehicle drive system>
First, based on FIG. 1, a schematic configuration of a vehicle drive system 1 to which the power converter 5 is applied will be described. As shown in FIG. 1, a vehicle drive system 1 includes a DC power supply 2, motor generators 3 and 4, and a power conversion device 5 that performs power conversion between the DC power supply 2 and the motor generators 3 and 4. there is

The DC power supply 2 is a chargeable/dischargeable secondary battery such as a lithium ion battery or a nickel hydrogen battery. The motor generators 3 and 4 are three-phase AC rotating electric machines. The motor generator 3 functions as a generator (alternator) that is driven by an engine (not shown) to generate electricity, and as an electric motor (starter) that starts the engine. The motor generator 4 functions as a vehicle driving source, that is, as an electric motor. It also functions as a generator during regeneration. The vehicle includes an engine and a motor generator 4 as a driving source.

<Circuit Configuration of Power Converter>
Next, the circuit configuration of the power conversion device 5 will be described. As shown in FIG. 1, the power converter 5 includes a converter 6, inverters 7 and 8, a control circuit section 9, a smoothing capacitor C1, a filter capacitor C2, and the like. The converter 6 and inverters 7 and 8 are power converters. The converter 6 is a DC-DC converter that converts a DC voltage into DC voltages of different values, and the inverters 7 and 8 are DC-AC converters. These power converters have upper and lower arm circuits 10, respectively.

The upper and lower arm circuit 10 has switching elements Q1 and Q2 and diodes D1 and D2. In this embodiment, n-channel IGBTs are used as the switching elements Q1 and Q2. The upper arm 10U includes a switching element Q1 and a freewheeling diode D1 connected in antiparallel. The lower arm 10L includes a switching element Q2 and a freewheeling diode D2 connected in antiparallel. Note that the switching elements Q1 and Q2 are not limited to IGBTs. For example, MOSFETs can also be employed. Parasitic diodes can also be used as the diodes D1 and D2.

The upper arm 10U and the lower arm 10L are connected in series between the VH line 12H and the N line 13 with the upper arm 10U on the VH line 12H side. The P line 12, which is a power line on the high potential side, has a VL line 12L in addition to the VH line 12H described above. The VL line 12L is connected to the positive terminal of the DC power supply 2 . A converter 6 is provided between the VL line 12L and the VH line 12H, and the potential of the VH line 12H is made equal to or higher than the potential of the VL line 12L. The N line 13 is connected to the negative electrode of the DC power supply 2, is a power line on the low potential side, and is also called a ground line. Thus, the upper arm circuit 10 is configured by connecting the upper arm 10U and the lower arm 10L in series between the power lines on the high potential side and the low potential side. Semiconductor modules 110 to be described later each include one upper and lower arm circuit 10 .

A collector electrode of the switching element Q1 is connected to the VH line 12H, and an emitter electrode of the switching element Q2 is connected to the N line 13. An emitter electrode of the switching element Q1 and a collector electrode of the switching element Q2 are connected.

Filter capacitor C2 is connected between VL line 12L and N line 13 . Filter capacitor C2 is connected in parallel with DC power supply 2 . Filter capacitor C2 removes power noise from DC power supply 2, for example. The filter capacitor C2 is also called a low voltage side capacitor because it is arranged on the lower voltage side than the smoothing capacitor C1. At least one of the N line 13 and the VL line 12L is provided with a system main relay (SMR) (not shown) between the DC power supply 2 and the filter capacitor C2.

The converter 6 has the above-described upper and lower arm circuit 10 and a reactor R1. Upper and lower arm circuit 10 is connected between VH line 12H and N line 13 . One end of the reactor R1 is connected to the VL line 12L, and the other end is connected to the connection point of the upper arm 10U and the lower arm 10L via the boost wiring 14. As shown in FIG. That is, the reactor R1 is arranged between the VL line 12L and the connection point of the upper and lower arm circuits 10. As shown in FIG.

The converter 6 converts the DC voltage into DC voltages of different values according to switching control by the control circuit unit 9 . Converter 6 has a function of stepping up the DC voltage supplied from DC power supply 2 . It also has a step-down function of charging the DC power supply 2 using the charge of the smoothing capacitor C1.

Smoothing capacitor C1 is connected between VH line 12H and N line 13 . The smoothing capacitor C1 is provided between the converter 6 and the inverters 7, 8 and is connected in parallel with the converter 6 and the inverters 7, 8. Smoothing capacitor C1 smoothes the DC voltage boosted by converter 6, for example, and accumulates the charge of the DC voltage. The voltage across the smoothing capacitor C1 becomes a DC high voltage for driving the motor generators 3 and 4. FIG. The voltage across the smoothing capacitor C1 is greater than or equal to the voltage across the filter capacitor C2. The smoothing capacitor C1 is also called a high voltage side capacitor because it is arranged on the high voltage side of the filter capacitor C2.

Inverter 7 is connected to converter 6 via smoothing capacitor C1. The inverter 7 has three sets of the upper and lower arm circuits 10 described above. That is, the inverter 7 has upper and lower arm circuits 10 for three phases. A connection point of the U-phase upper and lower arm circuits 10 is connected to a U-phase winding provided on the stator of the motor generator 3 . Similarly, the connection point of the V-phase upper and lower arm circuits 10 is connected to the V-phase winding of the motor generator 3 . A connection point of the W-phase upper and lower arm circuits 10 is connected to a W-phase winding of the motor generator 3 . The connection point of the upper and lower arm circuits 10 of each phase is connected to the winding of the corresponding phase via the output wiring 15 provided for each phase.

Inverter 7 converts the DC voltage into a three-phase AC voltage according to switching control by control circuit portion 9 and outputs the same to motor generator 3 . Thereby, the motor generator 3 is driven to generate a predetermined torque. Inverter 7 can also convert a three-phase AC voltage generated by motor generator 3 in response to the output of the engine into a DC voltage according to switching control by control circuit unit 9, and output the DC voltage to VH line 12H. Thus, inverter 7 performs bidirectional power conversion between converter 6 and motor generator 3 .

Similarly, inverter 8 is also connected to converter 6 via smoothing capacitor C1. The inverter 8 also has three sets of the upper and lower arm circuits 10 described above. That is, the inverter 8 has upper and lower arm circuits 10 for three phases. A connection point of the U-phase upper and lower arm circuits 10 is connected to a U-phase winding provided on the stator of the motor generator 4 . A connection point of the V-phase upper and lower arm circuits 10 is connected to a V-phase winding of the motor generator 4 . A connection point of the W-phase upper and lower arm circuits 10 is connected to a W-phase winding of the motor generator 4 . The connection point of the upper and lower arm circuits 10 of each phase is connected to the winding of the corresponding phase via the output wiring 15 provided for each phase.

Inverter 8 converts the DC voltage into a three-phase AC voltage and outputs the three-phase AC voltage to motor generator 4 in accordance with switching control by control circuit portion 9 . Thereby, the motor generator 3 is driven to generate a predetermined torque. Further, the inverter 8 converts the three-phase AC voltage generated by the motor generator 4 in response to the rotational force from the wheels during regenerative braking of the vehicle into a DC voltage according to the switching control of the control circuit unit 9, and converts it into a DC voltage. You can also output to Thus, inverter 8 performs bidirectional power conversion between converter 6 and motor generator 4 .

The control circuit section 9 is configured with, for example, a microcomputer. The control circuit unit 9 generates a drive command for operating the switching elements of the inverters 7 and 8, and outputs it to a drive circuit unit (driver) (not shown). Specifically, the control circuit unit 9 outputs a PWM signal as a drive command. The control circuit unit 9 generates a drive command based on a torque request input from a host ECU (not shown) and signals detected by various sensors.

The various sensors include a current sensor for detecting the phase current flowing through each phase winding of the motor generators 3 and 4, a rotation angle sensor for detecting the rotation angle of the rotors of the motor generators 3 and 4, and the voltage across the smoothing capacitor C1. a voltage sensor that detects the voltage of the VH line 12H, a voltage sensor that detects the voltage across the filter capacitor C2, that is, the voltage of the VL line 12L, a current sensor that is provided in the boost wiring 14 and detects the current flowing through the reactor R1, There is a temperature sensor or the like that detects the temperature of the reactor R1. The power conversion device 5 has these sensors (not shown).

The drive circuit section generates a drive signal based on a drive command from the control circuit section 9 and outputs it to the gate electrodes of the switching elements Q1 and Q2 of the corresponding upper and lower arm circuits 10 . As a result, the switching elements Q1 and Q2 are driven, that is, turned on and turned off. In this embodiment, a drive circuit section is provided for each upper and lower arm circuit 10 .

<Structure of power converter>
Next, the structure of the power converter 5 according to this embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 is a cross-sectional view of the power conversion device 5, and FIG. 3 is a cross-sectional view taken along line III--III in FIG. In the following description, the depth direction of the power conversion device 5 is referred to as the Z direction, which is perpendicular to the Z direction, and the stacking direction of the plurality of semiconductor modules 110 and the cooling pipes 106 is referred to as the X direction. A direction orthogonal to both the Z direction and the X direction is indicated as the Y direction.

2 and 3, the power conversion device 5 mainly includes a capacitor unit 102, a laminate 104 of a cooling pipe 106 and a semiconductor module 110, a reactor unit 120, a terminal block 134, a control circuit board 140, and the like. consists of These components are housed in case 100 . The case 100 is composed of an upper cover 100a, a main case 100b, a lower case 100c and a lower cover 100d.

Capacitor unit 102 has a generally rectangular parallelepiped shape as a whole, and includes smoothing capacitor C1 and filter capacitor C2 described above. For example, the capacitor unit 102 is formed by housing a plurality of film capacitors inside a case. The capacitor unit 102 is fixed to the main case 100b by screw fastening or the like.

2 and 3, a bus bar 128 connected to the positive terminal (power terminal) of the filter capacitor C2 in the capacitor unit 102 protrudes from the side surface of the capacitor unit 102 on the side of the reactor unit 120 and extends into the reactor unit 120. Only one power terminal 126 of the reactor R1 is shown. However, actually, each terminal of the smoothing capacitor C1 and the filter capacitor C2 other than the positive terminal of the filter capacitor C2 is connected to the power terminal (positive terminal, negative terminal) of the semiconductor module 110 via a bus bar (not shown). Connected. These bus bars are provided to protrude from the side surface of capacitor unit 102 on the side of reactor unit 120 (the side of laminate 104), like the bus bar connected to the positive terminal of filter capacitor C2. The bus bar is formed by, for example, pressing a metal plate material having excellent conductivity such as copper.

Each semiconductor module 110 forming the laminate 104 includes one upper and lower arm circuit 10 as described above. That is, one semiconductor module 110 incorporates a switching element Q1 and a freewheeling diode D1 that form the upper arm 10U, and a switching element Q2 and a freewheeling diode D2 that form the lower arm 10L. As described above, upper and lower arm circuits 10 are used in converter 6 and inverters 7 and 8, respectively. Upper and lower arm circuits 10 of converter 6 and inverters 7 and 8 are all modularized as semiconductor modules 110 .

Each semiconductor module 110 is obtained by sealing a semiconductor chip forming an upper arm 10U and a lower arm 10L with a sealing resin body. As shown in FIGS. 2 and 3, the semiconductor module 110 has a control terminal 112 and a power terminal 114 protruding from opposite end faces in the Z direction. More specifically, a plurality of control terminals 112 protrude from the upper surface on the side closer to the control circuit board 140, and a plurality of power terminals 114 protrude from the lower surface opposite to the upper surface.

As the control terminals 112, in each semiconductor module 110, five control terminals 112 protrude respectively from the upper arm 10U and the lower arm 10L. These five control terminals 112 are for the gate electrode, the Kelvin emitter for detecting the potential of the emitter electrode, the current sensing, and the anode potential and cathode potential of the temperature sensor (temperature sensitive diode) for detecting the temperature of the semiconductor chip. used as The control terminals 112 protruding from each semiconductor module 110 are fastened to the control circuit board 140 while penetrating the control circuit board 140, as shown in FIG.

On the other hand, as the power terminals 114 , three power terminals 114 protrude from each semiconductor module 110 . These three power terminals are connected to the positive terminal connected to the VH line 12H, the negative terminal connected to the N line 13, and the output wiring 15 to each phase of the reactor R1 and the motor generators 3 and 4. It is an AC terminal.

Cooling pipe 106 is formed using a metal material with excellent thermal conductivity, such as an aluminum-based material. For example, at least one of the pair of plates (thin metal plates) is processed into a shape bulging in the X direction by press working. After that, the outer peripheral edges of the pair of plates are fixed to each other by caulking or the like, and the entire circumference is joined to each other by brazing or the like. As a result, a channel through which a coolant can flow is formed between the pair of plates, and can be used as the cooling pipe 106 .

In this embodiment, in order to cool the semiconductor modules 110 that generate heat during operation, the semiconductor modules 110 and the cooling pipes 106 are alternately stacked to form the laminate 104 . The stack 104 is provided with two cooling pipes 108 that communicate with the flow paths of the plurality of stacked cooling pipes 106 . A pump (not shown) supplies a coolant to one of the cooling pipes 108 , causing the coolant to flow through the channels in the stacked cooling pipes 106 . Thereby, each semiconductor module 110 of the stacked body 104 is cooled by the coolant.

Furthermore, in the present embodiment, the refrigerant is configured to flow through the sealed space formed between the lower case 100c and the lower cover 100d. In order to allow the coolant to flow through the cooling pipe 106 of the laminate 104 and the sealed space between the lower case 100c and the lower cover 100d, for example, one cooling pipe 108 provided in the laminate 104 is connected to a connector provided outside the case 100 ( (not shown) to communicate with the space formed between the lower case 100c and the lower cover 100d. Alternatively, in the case 100, the flow path in the laminate 104 and the space formed between the lower case 100c and the lower cover 100d may be communicated. Alternatively, the coolant channel of the laminate 104 and the space formed between the lower case 100c and the lower cover 100d may be provided as two independent systems, and coolant may be supplied to each of the two systems from a pump (not shown). As described above, the power converter 5 according to the present embodiment includes a cooling mechanism that causes the coolant to flow through the cooling pipe 106 of the laminate 104 and the closed space formed between the lower case 100c and the lower cover 100d.

An elastic member 116 is provided between the laminate 104 and a first partition wall 118 provided in the main case 100b. The elastic member 116 presses the laminate 104 against the inner wall of the main case 100b. As a result, the laminate 104 is held at a fixed position within the case 100 .

Reactor unit 120, like capacitor unit 102, has a generally rectangular parallelepiped shape as a whole and includes a reactor R1. Reactor unit 120 is fixed to case 100 while being sandwiched between a second partition 122 and a third partition 124 provided in lower case 100c.

The reactor unit 120 has a first terminal 126 and a second terminal 130 as power terminals. The first terminal 126 is a terminal electrically connected to the positive terminal of the filter capacitor C2 via the bus bar 128 . The second terminal 130 is a terminal electrically connected to a power terminal (AC terminal) of the semiconductor module 110 constituting the converter 6 via a bus bar 136 formed on a terminal block 134 to be described later.

As shown in FIG. 3, the first terminal 126 and the second terminal 130 extend from the upper surface of the reactor unit 120 between the second and third partition walls 122 and 124 toward the control circuit board 140 along the Z direction. protruding. The protrusion height of the first terminal 126 and the second terminal 130 is lower than the upper surface of the semiconductor module 110 of the laminate 104, as shown in FIG. Therefore, when the first terminal 126 and the second terminal 130 of the reactor unit 120 are projected in the X direction, the control terminal 112 protruding from the upper surface of the semiconductor module 110 and the first terminal 126 and the second terminal 126 protruding from the upper surface of the reactor unit 120 are projected. The positional relationship is such that the two terminals 130 do not overlap each other.

Moreover, as shown in FIG. 2, both the first terminal 126 and the second terminal 130 of the reactor unit 120 have a substantially rectangular cross section. A surface corresponding to a long side of the substantially rectangular cross section is joined to one end of the above-described busbars 128 and 136 as a main surface of first terminal 126 and second terminal 130 . The main surfaces of the first terminals 126 and the second terminals 130 are parallel to the X direction, and parallel to the Y direction. is provided in reactor unit 120 so as to be orthogonal to .

Further, reactor unit 120 is provided with a temperature sensor that detects the temperature of reactor R1. A connection terminal 132 connected to the temperature sensor extends from the upper surface of the reactor unit 120 along the Z direction. The connection terminal 132 of the temperature sensor is fastened to the control circuit board 140 while passing through the control circuit board 140, as shown in FIG.

As shown in FIGS. 2 and 3, the second partition wall 122 and the third partition wall 124 sandwiching the reactor unit 120 have cavities 122a and 124a formed therein. A gap 125 is formed between the lower case 100c and the lower cover 100d in the lower portion of the lower case 100c on which the reactor unit 120 is mounted. The cavity 122a of the second partition wall 122 and the cavity 124a of the third partition wall 124 communicate with each other through a gap 125 between the lower case 100c and the lower cover 100d. Furthermore, although not shown, the gap 125 between the lower case 100c and the lower cover 100d extends to the lower portion of the lower case 100c on which the capacitor unit 102 is placed, and the capacitor unit 102 is mounted via a heat radiation sheet or the like (not shown). are in contact with the lower case 100c.

Therefore, when the cooling mechanism described above causes the coolant to flow in the sealed space formed between the cooling pipe 106 of the laminate 104 and the lower case 100c and the lower cover 100d, the coolant is added to the semiconductor module 110. , reactor unit 120 and condenser unit 102 are also cooled. In particular, regarding the reactor unit 120, since the second partition wall 122 and the third partition wall 124 that sandwich the reactor unit 120 are provided with cavities 122a and 124a through which the coolant flows, the reactor unit 120 can be cooled more effectively. be able to.

The terminal block 134 includes a plurality of bus bars 136 connected to the power terminals of the plurality of semiconductor modules 110, a plurality of terminals, a housing that holds them, and a terminal block 134 provided in the housing to detect current flowing through the power terminals of each semiconductor module 110. It is equipped with a current sensor, etc. The terminal block 134 is provided with connection terminals for connecting to the motor generators 3 and 4 . The connection terminals of terminal block 134 are connected to the three-phase windings of motor generators 3 and 4 through an opening of case 100 (not shown).

The control circuit board 140 is formed with the control circuit section 9 and the driving circuit section described above. That is, the control circuit board 140 is a printed circuit board on which various electronic components including a microcomputer are mounted. The control circuit board 140 is also mounted with a connector for connecting with a host ECU or the like.

<Technical features of the power converter>
Next, technical features of the power converter 5 according to this embodiment will be described. When it is attempted to reduce the height and size of the power conversion device 5 in order to improve mountability, etc., the distance between components that generate heat during operation, such as the laminate 104 having the semiconductor module 110, the capacitor unit 102, and the reactor unit 120, increases. will be narrowed. As a result, there arises a problem that the heat-generating components become susceptible to heat generation (thermal interference), making it difficult for the heat-generating components to dissipate heat sufficiently.

To address such a problem, the power converter 5 according to this embodiment includes a cooling mechanism that cools a plurality of heat-generating components (semiconductor module 110, reactor R1, capacitors C1 and C2) that generate heat during operation. Therefore, even if these heat-generating components generate heat during operation, the heat generation itself can be mitigated.

However, even if the heat-generating component is cooled by the cooling mechanism, it does not mean that heat is not generated during operation. For example, the semiconductor module 110 and the reactor unit 120 as heat-generating components are connected through power terminals and busbars, and when one heat-generating component generates heat, the heat is transferred to the other heat-generating components through power terminals and busbars, which are easy to conduct heat. be conveyed to However, in the power converter 5 according to the present embodiment, at least one of the power terminals 114 and 130 of the semiconductor module 110 and the reactor unit 120 projects from a side other than the side where the semiconductor module 110 and the reactor unit 120 face each other. In addition, the power terminals 114 and 130 are provided so that their protruding directions are different. More specifically, power terminals 114 and 130 of semiconductor module 110 and reactor unit 120, which are connected to each other via a bus bar, protrude in opposite directions. However, the power terminals of the reactor unit 120 do not necessarily have to protrude in the opposite direction.

As a result, it is possible to increase the length of the bus bar that connects the power terminals 114 and 130 of the semiconductor module 110 and the reactor unit 120 . As a result, heat transfer between semiconductor module 110 and reactor unit 120 can be suppressed, and thermal interference can be suppressed.

Furthermore, in the power conversion device 5 according to the present embodiment, at least one of the power terminals 114 and 130 of the semiconductor module 110 and the reactor unit 120 protrudes from a side other than the sides facing each other, and the power terminals 114 and 130 project in different directions, local temperature rise inside the case 100 due to radiant heat from the respective power terminals 114 and 130 can be suppressed.

Such a relationship in the direction in which the power terminals protrude is not limited to semiconductor module 110 and reactor unit 120 . For example, as described above, since the power terminals of the semiconductor module 110 and the capacitor unit 102 project in different directions, similar effects can be obtained. Further, the capacitor unit 102 has an XY plane (a plane perpendicular to the Z direction) so that the power terminals project from the capacitor unit 102 in the opposite direction to the power terminals of the semiconductor module 110. A power terminal may protrude from the top surface. Among the plurality of heat-generating components, since the reactor unit 120 and the capacitor unit 102 generate less heat than the semiconductor module 110, the power terminals of the reactor unit 120 and the capacitor unit 102 may project in the same direction. I do not care.

When the power terminals protrude from the side surfaces of reactor unit 120 and/or capacitor unit 102 , the protruding portion is set with respect to the center line of reactor unit 120 and/or capacitor unit 102 in the Z direction, and the power of semiconductor module 110 is determined. It is preferable to provide it on the side away from the terminal 114 . That is, since the power terminals 114 of the semiconductor module 110 are provided below the center line of the semiconductor module 110 in the Z direction in FIG. is preferably provided above the center line in the Z direction. In this case, the portion from which the power terminal of one heat generating component protrudes and the portion from which the power terminal of the other heat generating component protrudes are provided on opposite sides of the center line in the Z direction of each heat generating component. Become. As a result, the length of the bus bar that connects the power terminal 114 of the semiconductor module 110 and the power terminals of the reactor unit 120 and/or the capacitor unit 102 can be made as long as possible. In the configurations shown in FIGS. 2 and 3, the portion where the power terminal of one heat-generating component protrudes and the portion where the power terminal of the other heat-generating component protrudes are located across the center line of each heat-generating component in the Z direction. It's on the other side.

In addition, in the power conversion device 5 according to the present embodiment, the reactor unit 120 is cooled from three surfaces: the second partition wall 122, the third partition wall 124, and the inner surface of the case 100 on which the reactor unit 120 is mounted. . Conversely, in the power conversion device 5 according to the present embodiment, the power terminals of the semiconductor module 110 and the reactor unit 120 do not protrude in the same direction from the bottom surface of the same side, so the bottom surface of the reactor unit 120 is also a cooling object. can do. In this way, the cooling mechanism also cools the lower surface of the reactor unit 120 on the same side as the lower surface where the power terminal 114 protrudes from the semiconductor module 110, so that the local temperature rise inside the case 100 can be suppressed more effectively. can.

Further, in the power conversion device 5 according to the present embodiment, when the power terminals (the first terminal 126 and the second terminal 130) projecting from the reactor unit 120 are projected in the X direction, the control terminal projecting from the upper surface of the semiconductor module 110 112 are positioned so as not to overlap each other. That is, the control terminal 112 of the semiconductor module 110 and the power terminal of the reactor unit 120 are provided in different height ranges in the Z direction. Therefore, it becomes difficult for the noise component due to the magnetic flux generated by the current flowing through the power terminal of the reactor unit 120 to reach the control terminal 112 of the semiconductor module 110 . As a result, it is possible to prevent noise from the reactor unit 120 from being superimposed on various signals transmitted via the control terminal 112 of the semiconductor module 110 .

Furthermore, in the power conversion device 5 according to the present embodiment, the first terminal 126 and the second terminal 130 of the reactor unit 120 are arranged such that the main surface direction (X direction) of each semiconductor module 110 of the laminate 104 is the same as that of each semiconductor module 110 are provided in the reactor unit 120 so as to be orthogonal to the arrangement direction (Y direction) of the control terminals 112 of the . In other words, the first terminal 126 and the second terminal 130 of the reactor unit 120 are provided so that the side surfaces perpendicular to the main surface face the respective control terminals 112 of the plurality of semiconductor modules 110 .

When a current flows through first terminal 126 and second terminal 130 of reactor unit 120, most of the magnetic flux generated by the current is radiated from the main surface. In the present embodiment, the side surfaces of the first terminals 126 and the second terminals 130 perpendicular to the main surfaces face the control terminals 112 of the plurality of semiconductor modules 110 , so that the magnetic flux directed to the control terminals 112 of the semiconductor modules 110 can be reduced. Therefore, also from this point, it is possible to prevent noise from the reactor unit 120 from being superimposed on various signals transmitted via the control terminal 112 of the semiconductor module 110 .

Further, in the power conversion device 5 according to the present embodiment, the connection terminal 132 connected to the temperature sensor that detects the temperature of the reactor R1 is fastened to the control circuit board 140 while passing through the control circuit board 140 . Since no harness or the like is used to connect the temperature sensor and the control circuit board in this manner, assembly is facilitated and manufacturing costs can be reduced.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be implemented in various modifications without departing from the gist of the present invention. is.

For example, in the above-described embodiments, a water cooling mechanism using a refrigerant is adopted as a cooling mechanism for cooling a plurality of heat-generating components. However, an air cooling mechanism may be used as the cooling mechanism.

Moreover, in the power conversion device 5 according to the above-described embodiment, the power terminals of the reactor unit 120 and the semiconductor module 110 are connected using the bus bar 136 provided on the terminal block 134 . However, the power terminals of reactor unit 120 and semiconductor module 110 may be connected by a bus bar independent of terminal block 134 .

Further, in the power converter 5 according to the above-described embodiment, the reactor unit 120 has three cooling surfaces, but the number of the cooling surfaces may be one or two. Alternatively, five surfaces other than the top surface from which the power terminals protrude may be used as cooling surfaces.

Further, in the power conversion device 5 according to the above-described embodiment, the case 100 is composed of the four parts of the upper cover 100a, the main case 100b, the lower case 100c, and the lower cover 100d, but the case 100 is composed of three parts. There may be one or two. Alternatively, it may be composed of five or more parts.

Further, in the power conversion device 5 according to the present embodiment, the converter 6 includes one set of the reactor R1 and the upper and lower arm circuits 10, but may include a plurality of sets of the reactor R1 and the upper and lower arm circuits 10. . When multiple sets of reactors R1 and upper and lower arm circuits 10 are provided, they are connected in parallel with each other. The number of sets to be driven is switched according to the magnitude of the voltage required to charge the smoothing capacitor C1 in order to drive the motor generators 3 and 4. FIG. In this case, reactor unit 120 incorporates a plurality of reactors in a stacked state. At that time, cooling pipes may be interposed between the reactors, similarly to the semiconductor module 110 . The power terminals of the stacked reactors protrude in the same direction from the reactor unit.

1: drive system, 2: DC power supply, 3, 4: motor generator, 5: power converter, 6: converter, 7, 8: inverter, 9: control circuit unit, 10: upper and lower arm circuit, 10L: lower arm, 10U: upper arm, 12: P line, 13: N line, 14: boost wiring, 15: output wiring, 100: case, 100a: upper cover, 100b: main case, 100c: lower case, 100d: lower cover, 102: capacitor Unit 104: Laminate 106: Cooling pipe 108: Cooling pipe 110: Semiconductor module 112: Control terminal 114: Power terminal 116: Elastic member 118: First partition wall 120: Reactor unit 122 : second partition wall 124: third partition wall 134: terminal block 140: control circuit board

Claims (5)

A power conversion device (5) that converts a DC current to an AC current while transforming a voltage from a DC power supply,
a case (100) housing a plurality of electrical components that constitute the power conversion device;
a cooling mechanism for cooling a plurality of heat-generating components (102, 110, 120) that generate heat during operation among the plurality of electrical components;
Among the plurality of heat-generating components, at least a first heat-generating component (110) and a second heat-generating component (120) are arranged in the case along a direction perpendicular to the depth direction of the case. , having power terminals (114, 130) protruding from their respective heat-generating components;
further comprising a bus bar (136) connecting power terminals of the first and second heat generating components;
The portion where the power terminal of the first heat-generating component protrudes and the portion where the power terminal of the second heat-generating component protrudes are provided on opposite sides of the center line in the depth direction of each heat-generating component. , a direction in which the power terminal of the first heat-generating component protrudes is opposite to a direction in which the power terminal of the second heat-generating component protrudes.
The first heat-generating component is a semiconductor module in which a power terminal protrudes from a main body portion containing a power semiconductor element,
the second heat-generating component is a reactor,
The semiconductor module has a control terminal (112) protruding from a surface opposite to the surface from which the power terminal protrudes,
The power terminal of the reactor has a cross section consisting of long sides and short sides, and the surface corresponding to the long side is joined to one end of the bus bar, and the surface corresponding to the short side faces the control terminal of the semiconductor module. A power converter provided . 2. The semiconductor module according to claim 1 , wherein the semiconductor module is arranged in the case as a laminate (104) in which a plurality of semiconductor modules are stacked, and power terminals protrude in the same direction from the plurality of semiconductor modules. power converter. The power converter according to claim 1 or 2 , wherein the reactor is arranged in the case as a laminate in which a plurality of reactors are laminated, and power terminals protrude in the same direction from the plurality of reactors. Device. 4. The electric power according to any one of claims 1 to 3 , wherein the cooling mechanism also cools a surface of the second heat-generating component on the same side as a surface from which the power terminal protrudes from the first heat-generating component. conversion device. The power converter according to any one of claims 1 to 4, wherein the control terminal of the semiconductor module and the power terminal of the reactor are provided in different height ranges in the depth direction of the case .

Images