CN110798076B - Component module - Google Patents

Abstract

The invention provides an element module capable of suppressing increase of thickness and wiring inductance. The element module includes: at least one switching element; a cooling body disposed on a first surface side in a thickness direction of the switching element; a heat transfer body that is disposed on a second surface side in a thickness direction of the switching element, is thermally connected to the second surface and the cooling body, and transfers heat from the switching element to the cooling body; and a drive circuit that drives the switching element, wherein at least one of a circuit element and a signal line constituting the drive circuit is provided in the heat transfer body.

Description

Component module

Technical Field

The present invention relates to a component module. The application claims priority based on the japanese patent application No. 2018-146190 applied on 8/2/2018, the contents of which are incorporated herein by reference.

Background

Conventionally, there is known a power control unit in which a pair of coolers sandwich a power module from both sides in a thickness direction, the power module including a semiconductor device and a pair of dcb (direct Copper bonding) substrates sandwiching the semiconductor device from both sides in the thickness direction (see, for example, specification of U.S. patent application publication No. 2017/0096066). In this power control unit, the power modules are cooled from both sides in the thickness direction by a cooler such as a water jacket.

However, in the power control unit of the above-described conventional technique, since the pair of coolers is disposed on both sides in the thickness direction of the power module, the thickness and size of the power control unit increase.

In the power control unit according to the related art, it is necessary to dispose the control board for driving and controlling the semiconductor device so as to avoid the pair of coolers. Therefore, the wiring inductance may increase due to an increase in the distance between the semiconductor device and the control substrate. For example, when a semiconductor device is driven at a high frequency by a gate signal, a gate waveform may oscillate due to an increase in wiring inductance.

Disclosure of Invention

An aspect of the present invention is to provide an element module capable of suppressing an increase in wiring inductance while suppressing an increase in thickness.

The present invention adopts the following modes.

(1) An element module according to an aspect of the present invention includes: at least one switching element; a cooling body disposed on a first surface side in a thickness direction of the switching element; a heat transfer body that is disposed on a second surface side in a thickness direction of the switching element, is thermally connected to the second surface and the cooling body, and transfers heat from the switching element to the cooling body; and a drive circuit that drives the switching element, wherein at least one of a circuit element and a signal line constituting the drive circuit is provided in the heat transfer body.

(2) In the element module according to (1) above, the circuit element may include a resistor connected to a control terminal of the switching element, and the resistor may be provided in the heat transfer body.

(3) In the element module according to the above (1) or (2), the signal line may be provided on the heat transfer body.

(4) In the element module according to the above (3), the signal terminals connected to the signal lines may be disposed at positions overlapping with the heat transfer body in the thickness direction.

According to the aspect (1), since the cooling body is disposed on the first surface side in the thickness direction of the switching element and the heat transfer body for transferring heat to the cooling body is disposed on the second surface side, the switching element is cooled from both surfaces (the first surface and the second surface) by the cooling body. This can improve the cooling performance as compared with, for example, a case where the switching element is cooled only from one side, and can suppress an increase in thickness as compared with, for example, a case where a pair of cooling bodies are arranged on both sides of the switching element.

Further, since at least one of the circuit element and the signal line constituting the drive circuit is provided on the heat transfer body, an increase in the distance between the switching element and the circuit element or the signal line of the drive circuit can be suppressed. This can suppress an increase in wiring inductance, compared to a case where, for example, circuit elements of the driver circuit and the signal line are arranged so as to avoid the heat transfer body.

In the case of the aspect (2), as compared with a case where the resistor is disposed so as to avoid the heat transfer body, for example, an increase in the distance between the control electrode of the switching element and the resistor and an increase in the wiring inductance can be suppressed, and oscillation of the gate waveform due to an increase in the wiring inductance can be further suppressed.

In the case of the aspect (3), for example, the element module can be prevented from being enlarged as compared with a case where the signal line is arranged so as to avoid the heat transfer body.

In the case of the aspect (4), it is possible to suppress an increase in size of the element module, compared to a case where the signal terminals are arranged so as not to overlap with the heat transfer body, for example.

Drawings

Fig. 1 is a perspective view schematically showing the structure of a power module of a power conversion device according to an embodiment of the present invention.

Fig. 2 is a perspective view schematically showing a part of a power module of a power conversion device according to an embodiment of the present invention.

Fig. 3 is a plan view of a power module of a power conversion device according to an embodiment of the present invention, as viewed from the thickness direction.

Fig. 4 is a sectional view taken along a plane parallel to the thickness direction at the position of line a-a shown in fig. 3.

Fig. 5 is a sectional view taken along a plane parallel to the thickness direction at the position of line B-B shown in fig. 3.

Fig. 6 is a sectional view taken along a plane parallel to the thickness direction at the position of line C-C shown in fig. 3.

Fig. 7 is a diagram showing a configuration of a part of a vehicle on which a power conversion device according to an embodiment of the present invention is mounted.

Fig. 8 is a diagram showing gate resistances connected between the gates of the transistors and the gate driving unit in the power conversion device according to the embodiment of the present invention.

Detailed Description

Hereinafter, an embodiment of an element module according to the present invention will be described with reference to the drawings.

The element module of the present embodiment constitutes, for example, a power conversion device that controls power transmission and reception between a motor and a battery. For example, the power converter is mounted on an electric vehicle or the like. The electric vehicle is an electric automobile, a hybrid vehicle, a fuel cell vehicle, or the like. The electric vehicle is driven by using a storage battery as a power source. The hybrid vehicle is driven by a battery and an internal combustion engine as power sources. A fuel cell vehicle is driven by using a fuel cell as a power source.

Fig. 1 is a perspective view schematically showing the structure of a power module 21 of a power conversion device 1 according to an embodiment of the present invention. Fig. 2 is a perspective view schematically showing a part of the power module 21 of the power conversion device 1 according to the embodiment of the present invention. Fig. 3 is a plan view of a part of the power module 21 of the power converter 1 according to the embodiment of the present invention as viewed from the thickness direction. Fig. 4 is a sectional view taken along a plane parallel to the thickness direction at the position of line a-a shown in fig. 3. Fig. 5 is a sectional view taken along a plane parallel to the thickness direction at the position of line B-B shown in fig. 3. Fig. 6 is a sectional view taken along a plane parallel to the thickness direction at the position of line C-C shown in fig. 3. Fig. 7 is a diagram showing a configuration of a part of a vehicle 10 on which the power conversion device 1 according to the embodiment of the present invention is mounted. Fig. 8 is a diagram showing gate resistances between the gates of the transistors and the gate driving unit (driving circuit) 29 in the power conversion device 1 according to the embodiment of the present invention.

< vehicle >

As shown in fig. 7, the vehicle 10 includes a battery 11(BATT), a first motor 12(MOT) for driving and traveling, and a second motor 13(GEN) for generating electric power, in addition to the power conversion device 1.

The battery 11 is, for example, a high-voltage battery as a power source of the vehicle 10. The battery 11 includes a battery case and a plurality of battery modules housed in the battery case. The battery module includes a plurality of battery cells connected in series.

The battery 11 includes a positive electrode terminal PB and a negative electrode terminal NB connected to the dc connector 1a of the power conversion device 1. The positive electrode terminal PB and the negative electrode terminal NB are connected to positive electrode terminals and negative electrode terminals of a plurality of battery modules connected in series in the battery case.

The first motor 12 generates a rotational driving force (power running operation) by the electric power supplied from the battery 11. The second motor 13 generates generated electric power by the rotational driving force input to the rotating shaft. The second motor 13 is configured to be able to transmit rotational power of the internal combustion engine. For example, the first motor 12 and the second motor 13 are three-phase ac brushless DC motors, respectively. The three phases are a U phase, a V phase and a W phase. The first motor 12 and the second motor 13 are each of an inner rotor type.

Each of the motors 12 and 13 includes: a rotating member having a permanent magnet for excitation; and a stationary member having three-phase stator windings for generating a rotating magnetic field for rotating the rotating member.

The three-phase stator windings of the first motor 12 are connected to the first three-phase connector 1b of the power conversion device 1. The stator windings of the three phases of the second motor 13 are connected to the second three-phase connector 1c of the power conversion device 1.

< Power conversion device >

The power conversion device 1 includes a power module 21, a reactor 22, a capacitor unit 23, a resistor 24, a first current sensor 25, a second current sensor 26, a third current sensor 27, an electronic control unit 28(MOT GEN ECU), and a gate drive unit 29(G/D VCU ECU).

The power module 21 includes a first power conversion circuit unit 31, a second power conversion circuit unit 32, and a third power conversion circuit unit 33. The first power conversion circuit unit 31 is connected to the three-phase stator windings of the first motor 12 by the first three-phase connector 1 b. The first power conversion circuit unit 31 converts the direct-current power input from the battery 11 via the third power conversion circuit unit 33 into three-phase alternating-current power. The second power conversion circuit unit 32 is connected to the three-phase stator windings of the second motor 13 via the second three-phase connector 1 c. The second power conversion circuit unit 32 converts the three-phase ac power input from the second motor 13 into dc power. The dc power converted by the second power conversion circuit unit 32 can be supplied to at least one of the battery 11 and the first power conversion circuit unit 31.

Each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32 includes a bridge circuit formed by a plurality of bridge-connected switching elements. For example, the switching element is a Transistor such as an igbt (insulated Gate Bipolar Transistor) or a MOSFET (Metal Oxide semiconductor Field Effect Transistor). For example, in the bridge circuit, paired high-side arm and low-side arm U-phase transistors (switching elements) UH and UL, paired high-side arm and low-side arm V-phase transistors (switching elements) VH and VL, and paired high-side arm and low-side arm W-phase transistors (switching elements) WH and WL are bridged, respectively.

The high-side arms are formed by connecting collectors of the transistors UH, VH, and WH to a positive bus line PI. In each phase, each positive bus line PI of the high-side arm is connected to the positive bus line 50p of the capacitor unit 23.

The transistors UL, VL, and WL in the low-side arm are configured by connecting the emitter to the negative bus NI. In each phase, each negative bus NI of the low-side arm is connected to negative bus 50n of capacitor unit 23.

In each phase, the emitter of each transistor UH, VH, WH of the high-side arm is connected to the collector of each transistor UL, VL, WL of the low-side arm at a connection point TI.

In each phase of the first power conversion circuit unit 31, a first bus bar 51 forming a connection point TI is connected to the first input/output terminal Q1. The first input/output terminal Q1 is connected to the first three-phase connector 1 b. A connection point TI of each phase of the first power conversion circuit unit 31 is connected to the stator winding of each phase of the first motor 12 via the first bus bar 51, the first input/output terminal Q1, and the first three-phase connector 1 b.

In each phase of the second power conversion circuit unit 32, the second bus bar 52 forming the connection point TI is connected to the second input/output terminal Q2. The second input/output terminal Q2 is connected to the second three-phase connector 1 c. A connection point TI of each phase of the second power conversion circuit unit 32 is connected to the stator winding of each phase of the second motor 13 via the second bus bar 52, the second input/output terminal Q2, and the second three-phase connector 1 c.

The bridge circuit includes diodes connected between the collector and the emitter of each of the transistors UH, UL, VH, VL, WH, WL in a forward direction from the emitter to the collector.

The first power conversion circuit unit 31 and the second power conversion circuit unit 32 switch the pair of transistors of each phase on (on)/off (off) based on gate signals, which are switching commands input from the gate drive unit 29 to the gates of the transistors UH, VH, WH, UL, VL, and WL, respectively. The first power conversion circuit unit 31 converts direct-current power input from the battery 11 via the third power conversion circuit unit 33 into three-phase alternating-current power, and sequentially commutates the energization of the three-phase stator windings of the first motor 12, thereby energizing the three-phase stator windings with an alternating-current U-phase current, V-phase current, and W-phase current. The second power conversion circuit unit 32 converts the three-phase ac power output from the three-phase stator windings of the second motor 13 into dc power by on (on)/off (off) driving of the transistor pairs of each phase in synchronization with the rotation of the second motor 13.

The third power conversion circuit unit 33 is a Voltage Control Unit (VCU). The third power conversion circuit unit 33 includes switching elements of a pair of a high-side arm and a low-side arm. For example, the third power conversion circuit unit 33 includes a first transistor (switching element) S1 for the high-side arm and a second transistor (switching element) S2 for the low-side arm.

The first transistor S1 has a collector connected to the positive bus PV to form a high-side arm. The positive bus PV of the high-side arm is connected to the positive bus 50p of the capacitor unit 23. The second transistor S2 has an emitter connected to the negative bus NV to form a low-side arm. The negative bus NV of the lower arm is connected to the negative bus 50n of the capacitor unit 23. Negative electrode bus bar 50n of capacitor unit 23 is connected to negative electrode terminal NB of battery 11. The emitter of the first transistor S1 of the high side arm is connected to the collector of the second transistor S2 of the low side arm. The third power conversion circuit unit 33 further includes a diode connected between the collector and the emitter of each of the first transistor S1 and the second transistor S2 so as to be forward from the emitter to the collector.

A third bus bar 53 forming a connection point of the first transistor S1 of the high side arm and the second transistor S2 of the low side arm is connected to the reactor 22. The reactor 22 has two ends, and a connection point between the first transistor S1 and the second transistor S2 is connected to a positive electrode terminal PB of the battery 11. The reactor 22 includes a coil and a temperature sensor for detecting the temperature of the coil. The temperature sensor is connected to the electronic control unit 28 through a signal line.

The third power conversion circuit unit 33 switches the pair of transistors on (on)/off (off) based on a gate signal that is a switching command input from the gate drive unit 29 to the gates of the first transistor S1 and the second transistor S2.

The third power conversion circuit unit 33 alternately switches, during boosting, a first state in which the second transistor S2 is set to on (conducting) and the first transistor S1 is set to off (blocking), and a second state in which the second transistor S2 is set to off (blocking) and the first transistor S1 is set to on (conducting). In the first state, a current flows to the positive terminal PB of the battery 11, the reactor 22, the second transistor S2, and the negative terminal NB of the battery 11 in this order, and the reactor 22 is excited by a direct current to store magnetic energy. In the second state, an electromotive force (induced voltage) is generated between both ends of the reactor 22 so as to prevent a change in magnetic flux caused by the current flowing through the reactor 22 being cut off. The induced voltage obtained from the magnetic energy stored in the reactor 22 is superimposed on the battery voltage, and a boosted voltage higher than the voltage between the terminals of the battery 11 is applied between the positive bus PV and the negative bus NV of the third power conversion circuit unit 33.

The third power conversion circuit unit 33 alternately switches the second state and the first state during regeneration. In the second state, a current flows to the positive bus PV of the third power conversion circuit unit 33, the first transistor S1, the reactor 22, and the positive terminal PB of the battery 11 in this order, and the reactor 22 is excited by a direct current to store magnetic energy. In the first state, an electromotive force (induced voltage) is generated between both ends of the reactor 22 so as to prevent a change in magnetic flux caused by the current flowing through the reactor 22 being turned off. The induced voltage obtained from the magnetic energy stored in the reactor 22 is stepped down, and a stepped-down voltage lower than the voltage between the positive bus PV and the negative bus NV of the third power conversion circuit unit 33 is applied between the positive terminal PB and the negative terminal NB of the battery 11.

The capacitor unit 23 includes a first smoothing capacitor 41, a second smoothing capacitor 42, and a noise filter 43.

The first smoothing capacitor 41 is connected between the positive electrode terminal PB and the negative electrode terminal NB of the battery 11. The first smoothing capacitor 41 smoothes voltage fluctuations that occur in association with the on/off switching operation of the first transistor S1 and the second transistor S2 during regeneration of the third power conversion circuit unit 33.

The second smoothing capacitor 42 is connected between the positive electrode bus PI and the negative electrode bus NI of each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32, and between the positive electrode bus PV and the negative electrode bus NV of the third power conversion circuit unit 33. The second smoothing capacitor 42 is connected to the plurality of positive bus lines PI and negative bus lines NI, and the positive bus line PV and negative bus line NV via the positive bus line 50p and the negative bus line 50 n. The second smoothing capacitor 42 smoothes voltage fluctuations that occur in association with the on/off switching operation of each of the transistors UH, UL, VH, VL, WH, WL of the first power conversion circuit unit 31 and the second power conversion circuit unit 32. The second smoothing capacitor 42 smoothes voltage fluctuations that occur in association with the on/off switching operation of the first transistor S1 and the second transistor S2 during the voltage boosting of the third power conversion circuit unit 33.

The noise filter 43 is connected between the positive bus PI and the negative bus NI of each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32, and between the positive bus PV and the negative bus NV of the third power conversion circuit unit 33. The noise filter 43 includes two capacitors connected in series. The connection point of the two capacitors is connected to the body ground of the vehicle 10 or the like.

The resistor 24 is connected between the positive bus PI and the negative bus NI of each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32, and between the positive bus PV and the negative bus NV of the third power conversion circuit unit 33.

The first current sensor 25 is disposed on the first bus bar 51 that constitutes the connection point TI of each phase of the first power conversion circuit unit 31 and is connected to the first input/output terminal Q1, and detects the current in each of the U-phase, the V-phase, and the W-phase. The second current sensor 26 is disposed on the second bus bar 52 that constitutes the connection point TI of each phase of the second power conversion circuit unit 32 and is connected to the second input/output terminal Q2, and detects the current in each of the U-phase, the V-phase, and the W-phase. The third current sensor 27 is disposed on the third bus 53 that constitutes a connection point between the first transistor S1 and the second transistor S2 and is connected to the reactor 22, and detects a current flowing through the reactor 22.

The first current sensor 25, the second current sensor 26, and the third current sensor 27 are connected to an electronic control unit 28 through signal lines, respectively.

The electronic control unit 28 controls the operation of each of the first motor 12 and the second motor 13. For example, the electronic control unit 28 is a software function unit that functions by executing a predetermined program using a processor such as a cpu (central Processing unit). The software function unit is an ecu (electronic Control unit) including a processor such as a CPU, a rom (read Only memory) storing a program, a ram (random Access memory) temporarily storing data, and an electronic circuit such as a timer. At least a part of the electronic control unit 28 may be an integrated circuit such as an lsi (large Scale integration). For example, the electronic control unit 28 generates a control signal to be input to the gate drive unit 29 by executing feedback control or the like using the current detection value of the first current sensor 25 and the current of the current target value corresponding to the torque command value for the first motor 12. For example, the electronic control unit 28 generates a control signal to be input to the gate drive unit 29 by executing feedback control or the like using the current detection value of the second current sensor 26 and a current of a current target value corresponding to a regeneration command value for the second motor 13. The control signal is a signal indicating timing for driving the transistors UH, VH, WH, UL, VL, and WL of each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32 to be turned on (on)/off (off). For example, the control signal is a pulse width modulated signal or the like.

The gate driving unit 29 generates gate signals for actually driving the transistors UH, VH, WH, UL, VL, and WL of each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32 to be turned on (on)/off (off) based on the control signal received from the electronic control unit 28. For example, the gate driving unit 29 generates a gate signal by performing amplification, level shift, and the like of a control signal.

The gate driving unit 29 generates a gate signal for driving each of the first transistor S1 and the second transistor S2 of the third power conversion circuit section 33 to be turned on (on)/off (off). For example, the gate driving unit 29 generates a gate signal having a duty ratio corresponding to a step-up voltage command at the time of step-up of the third power conversion circuit unit 33 or a step-down voltage command at the time of regeneration of the third power conversion circuit unit 33. The duty cycle is the ratio of the first transistor S1 to the second transistor S2.

As shown in fig. 8, the gate driving unit 29 includes, for example, an integrated circuit 60 and a plurality of gate resistors 61 (circuit elements, resistors). The gate resistors 61 are connected to the gates of the transistors UH, VH, WH, UL, VL, and WL in each of the first power conversion circuit unit 31 and the second power conversion circuit unit 32, and the gates of the transistors S1 and S2 in the third power conversion circuit unit 33. The integrated circuit 60 is connected to the transistors UH, VH, WH, UL, VL, WL, S1, S2 and the gate resistors 61 via signal lines 62.

< component Module >

As shown in fig. 1, the power module 21 includes a module case 80. The power module 21 includes, for example, an element module formed of switching elements of the high-side arm and the low-side arm of the first, second, and third power conversion circuit units 31, 32, and 33 described above in the module case 80.

In the first power conversion circuit unit 31, the high-side and low-side arm U-phase transistors UH and UL form an element block MU1, the high-side and low-side arm V-phase transistors VH and VL form an element block MV1, and the high-side and low-side arm W-phase transistors WH and WL form an element block MW 1.

In the second power conversion circuit unit 32, the high-side and low-side arm U-phase transistors UH and UL form an element block MU2, the high-side and low-side arm V-phase transistors VH and VL form an element block MV2, and the high-side and low-side arm W-phase transistors WH and WL form an element block MW 2.

In the third power conversion circuit unit 33, the first transistor S1 of the high side arm and the second transistor S2 of the low side arm form an element block MS.

The details of the element modules MU1, MV1, MW1, MU2, MV2, MW2, and MS will be described below. Note that, since the element modules MU1, MV1, MW1, MU2, MV2, MW2, and MS have the same configuration, for example, the configuration of the element module MU1 including the U-phase high-side arm U-phase transistor UH and the U-phase low-side arm transistor UL of the U-phase of the first power conversion circuit unit 31 will be described as a representative example.

In the following description, the directions of the X, Y, and Z axes orthogonal to each other in the three-dimensional space are directions parallel to the respective axes. For example, as shown in fig. 2, the thickness direction of the element module MU1 is parallel to the Z-axis direction. The direction in which the switching elements of the high-side arm and the low-side arm are arranged, that is, the direction in which the high-side arm U-phase transistor UH and the low-side arm U-phase transistor UL are arranged, is parallel to the X-axis direction. The Y-axis direction is orthogonal to the Z-axis direction and the X-axis direction.

As shown in fig. 2 and 3, the element module MU1 includes, for example, high-side arm and low-side arm U-phase transistors UH and UL, an insulating substrate 81, a positive bus bar PI and a negative bus bar NI, a first bus bar 51, a cooling body 82, a first heat transfer body 83 and a second heat transfer body 84, a first substrate 85 and a second substrate 86, a first signal terminal 87 and a second signal terminal 88, a conductive line 89, and a conductive spacer 90.

For example, the high-side arm and low-side arm U-phase transistors UH and UL are mounted on the insulating substrate 81 and fixed to a resin molded body (not shown) formed by molding using an electrically insulating resin material. The resin molded body fixes all the constituent components of the element module MU1 with a resin material.

The insulating substrate 81 includes an electrically insulating substrate and conductors provided on both surfaces of the substrate. For example, the insulating substrate 81 is a dcb (direct coater bonding) substrate. The DCB substrate includes a ceramic substrate 81a, and a first copper plate 81b, a second copper plate 81c, a third copper plate 81d, a fourth copper plate 81e, and a fifth copper plate 81f provided on both surfaces of the ceramic substrate 81a in the thickness direction. The first copper plate 81b, the second copper plate 81c, the third copper plate 81d, the fourth copper plate 81e, and the fifth copper plate 81f are electrically insulated from the ceramic substrate 81a with both sides of the ceramic substrate 81a in the thickness direction therebetween. The second copper plate 81c, the third copper plate 81d, the fourth copper plate 81e, and the fifth copper plate 81f are disposed apart from each other at a predetermined interval and are electrically insulated.

In the insulating substrate 81, the surface of the first copper plate 81b includes a cooling surface in contact with the cooling body 82. The surface of the second copper plate 81c includes a mounting surface on which the high-side arm U-phase transistor UH is mounted, and the surface of the third copper plate 81d includes a mounting surface on which the low-side arm U-phase transistor UL is mounted. The surface of the fourth copper plate 81e includes a heat transfer surface in contact with the first heat transfer body 83, and the surface of the fifth copper plate 81f includes a heat transfer surface in contact with the second heat transfer body 84.

As shown in fig. 4, the high-side arm and low-side arm U-phase transistors UH and UL are arranged in the X-axis direction when viewed from the Z-axis direction in a state where the front and back surfaces thereof are oriented in the same direction in the Z-axis direction. For example, the high-side arm and low-side arm U-phase transistors UH and UL are arranged such that the collector-side surfaces CS face the insulating substrate 81 in the Z-axis direction. The collector-side surface CS of the high-side arm U-phase transistor UH faces the mounting surface of the second copper plate 81c in the Z-axis direction, and the collector-side surface CS of the low-side arm U-phase transistor UL faces the mounting surface of the third copper plate 81d in the Z-axis direction.

The positive bus bar PI, the negative bus bar NI, and the first bus bar 51 are each a plate-like conductor such as a copper plate.

As shown in fig. 4 and 5, the collector-side surface CS of the high-side arm U-phase transistor UH is electrically joined to the surface of the second copper plate 81c of the insulating substrate 81 by a conductive joining material. For example, the bonding material is solder or the like. The positive electrode bus bar PI is electrically joined to the surface of the second copper plate 81c by a conductive joining material. In other words, the collector of the high-side arm U-phase transistor UH and the positive bus line PI are electrically connected via the second copper plate 81 c. The emitter-side surface ES of the high-side arm U-phase transistor UH is electrically connected to the first bus bar 51 via a conductive spacer 90. The conductive spacer 90 is a conductive body formed in a plate shape such as a copper plate. The conductive spacer 90 is disposed between the first bus bar 51 and the high-side arm U-phase transistor UH in the Z-axis direction, and is electrically joined to the first bus bar 51 and the emitter-side surface ES of the high-side arm U-phase transistor UH by a conductive joining material.

As shown in fig. 4 and 6, the collector-side surface CS of the low-side-arm U-phase transistor UL is electrically joined to the surface of the third copper plate 81d of the insulating substrate 81 by a conductive joining material. The first bus bar 51 is electrically joined to the surface of the third copper plate 81d by a conductive joining material. In other words, the collector of the low-side arm U-phase transistor UL is electrically connected to the first bus bar 51 via the third copper plate 81 d. The emitter-side surface ES of the low-side arm U-phase transistor UL is electrically connected to the negative bus bar NI via the conductive spacer 90. The conductive spacer 90 is disposed between the negative bus bar NI and the low-side arm U-phase transistor UL in the Z-axis direction, and is electrically joined to the negative bus bar NI and the emitter-side surface ES of the low-side arm U-phase transistor UL by a conductive joining material.

Positive bus bar PI and negative bus bar NI protrude outside module case 80 toward the negative direction side in the Y axis direction, for example, and are connected to positive bus bar 50p and negative bus bar 50n of capacitor unit 23.

The first bus bar 51 projects to the outside of the module case 80 toward, for example, the positive Y-axis direction, and is connected to the U-phase stator winding of the first motor 12 via the first input/output terminal Q1 and the first three-phase connector 1 b.

The cooling body 82 is a cooler such as a water jacket. A coolant flow path through which a coolant flows is formed inside the cooling body 82. Further, the cooling body 82 includes a plurality of fins that function as a heat sink at a portion of a wall surface forming the coolant flow path.

The cooling body 82 is disposed on the side of the surface CS on the collector side of the high-side arm and low-side arm U-phase transistors UH and UL, for example, in the Z-axis direction. The cooling body 82 is thermally bonded to the surface of the first copper plate 81b of the insulating substrate 81 via a bonding material.

The first heat transfer element 83 and the second heat transfer element 84 are plate-shaped members having high thermal conductivity, such as heat pipes or copper plates. The thickness of each heat transfer body 83, 84 in the Z-axis direction is formed smaller than the thickness of the cooling body 82 in the Z-axis direction.

As shown in fig. 4, 5, and 6, the heat conductors 83 and 84 are disposed on the emitter-side surfaces ES of the high-side arm and low-side arm U-phase transistors UH and UL, respectively, in the Z-axis direction, for example. The first heat conductor 83 is disposed so as to overlap the high-side arm U-phase transistor UH with the first bus bar 51 interposed therebetween when viewed in the Z-axis direction, and is thermally bonded to the surface of the first bus bar 51 with a bonding material. The second heat transfer element 84 is disposed so as to be spaced from the low-side arm U-phase transistor UL by the negative bus bar NI when viewed in the Z-axis direction, and is thermally bonded to the surface of the negative bus bar NI with a bonding material.

The first heat transfer element 83 and the second heat transfer element 84 are formed in plate shapes extending in the Y-axis direction, for example, inside the module case 80.

For example, the positive direction side end 83a of the Y axis direction of the first heat transfer body 83 is bent so as to approach the fourth copper plate 81e of the insulating substrate 81 in the Z axis direction, and is thermally bonded to the surface of the fourth copper plate 81e by a bonding material.

For example, the positive direction side end 84a of the second heat transfer element 84 in the Y axis direction is bent so as to approach the fifth copper plate 81f of the insulating substrate 81 in the Z axis direction, and is thermally bonded to the surface of the fifth copper plate 81f by a bonding material.

The first heat transfer member 83 transfers heat from the high-side arm U-phase transistor UH to the cooling member 82 via the conductive spacer 90, the first bus bar 51, and the insulating substrate 81. The second heat conductor 84 transfers heat from the low-side arm U-phase transistor UL to the cooling body 82 via the conductive spacer 90, the negative bus bar NI, and the insulating substrate 81.

The first substrate 85 and the second substrate 86 each include an electrically insulating substrate and a wiring of a conductor provided on a surface of the substrate. The first substrate 85 and the second substrate 86 are, for example, epoxy glass substrates. The first substrate 85 is disposed on the surface of the first heat transfer body 83, and the second substrate 86 is disposed on the surface of the second heat transfer body 84.

At least one of the electronic components constituting the gate driving unit 29 is provided on the surface of each of the first substrate 85 and the second substrate 86. For example, at least one of the circuit elements and the signal lines constituting the gate driving unit 29 is provided on the first heat transfer element 83 and the second heat transfer element 84 via the first substrate 85 and the second substrate 86, respectively. For example, the signal lines 62 formed of conductive wiring are provided on the surfaces of the first substrate 85 and the second substrate 86. Circuit elements such as a gate resistor 61 connected to the signal line 62 are mounted on the surfaces of the first substrate 85 and the second substrate 86 by soldering. The wiring and the electronic components provided on the surfaces of the first substrate 85 and the second substrate 86 are electrically insulated from the first heat transfer element 83 and the second heat transfer element 84 by the insulating substrates of the first substrate 85 and the second substrate 86.

A first signal terminal 87 connected to the signal line 62 is provided on the surface of the first substrate 85 at the end 83a of the first heat transfer body 83. A second signal terminal 88 connected to the signal line 62 is provided on the surface of the second substrate 86 at the end 84a of the second heat transfer body 84. The first signal terminal 87 and the second signal terminal 88 are formed in pin shapes extending in the positive direction of the Z-axis direction, for example. Thus, the first signal terminal 87 and the second signal terminal 88 are disposed at positions overlapping the first heat transfer element 83 and the second heat transfer element 84 in the Z-axis direction. The first signal terminal 87 and the second signal terminal 88 are connected to the gate driving unit 29 (for example, the substrate 29a on which the integrated circuit 60 is mounted).

As shown in fig. 2 and 3, the signal terminals Q (for example, gate terminals or the like which are control terminals to which control signals are input) of the high-side arm and low-side arm U-phase transistors UH and UL are electrically connected to the signal lines 62 formed of the respective wirings of the first substrate 85 and the second substrate 86 through conductive lines 89.

In the above description, the U-phase element module MU1 of the first power conversion circuit unit 31 was described, but the V-phase and W-phase element modules MV1 and MW1 of the first power conversion circuit unit 31 include V-phase transistors VH and VL or W-phase transistors WH and WL instead of the U-phase transistors UH and UL. The element modules MU2, MV2, and MW2 of the respective phases of the second power conversion circuit unit 32 include the second bus bar 52 instead of the first bus bar 51.

Further, the element module MS of the third power conversion circuit unit 33 includes, in comparison with the U-phase element module MU1 of the first power conversion circuit unit 31, the first and second transistors S1 and S2 instead of the respective U-phase transistors UH and UL, the positive bus PV and the negative bus NV instead of the positive bus PI and the negative bus NI, and the third bus 53 instead of the first bus 51.

As described above, according to the element modules MU1, MV1, MW1, MU2, MV2, MW2, and MS of the present embodiment, the cooling body 82 is disposed on the collector side in the thickness direction of the switching element, and the first heat transfer body 83 and the second heat transfer body 84 for transferring heat to the cooling body 82 are disposed on the emitter side. Thus, the switching elements are cooled from both sides (the collector side and the emitter side) by the cooling body 82, and the cooling performance can be improved as compared with a case where the switching elements are cooled from only one side, for example. In addition, as compared with a case where a pair of cooling bodies are disposed on both surfaces of the switching element, for example, by disposing heat transfer body 84 formed thinner than cooling body 82 on one surface side, an increase in thickness as a whole can be suppressed.

At least one of circuit elements and signal lines constituting the gate driving unit 29 for driving and controlling the switching elements is provided on the first substrate 85 and the second substrate 86 disposed on the first heat transfer element 83 and the second heat transfer element 84. This can suppress an increase in the distance between the switching element and the circuit element or the signal line of the gate driver unit 29, and can suppress an increase in the wiring inductance compared to, for example, a case where the circuit element or the signal line of the gate driver unit 29 is arranged so as to avoid the first heat transfer element 83 and the second heat transfer element 84.

Further, since the gate resistor 61 is provided on the first substrate 85 and the second substrate 86, it is possible to suppress an increase in the distance between the gate of the switching element and the gate resistor 61 and an increase in the wiring inductance, and to suppress oscillation of the gate waveform during high-frequency driving. Further, since the oscillation of the gate waveform can be suppressed, it is possible to suppress an increase in size of a member for smoothing the waveform, such as a reactor.

Further, since the signal lines 62 are provided on the first substrate 85 and the second substrate 86 and the first signal terminals 87 and the second signal terminals 88 are arranged at positions overlapping the first heat transfer element 83 and the second heat transfer element 84 in the Z-axis direction, the element modules MU1, MV1, MW1, MU2, MV2, MW2, and MS can be prevented from being enlarged.

A modified example of the embodiment will be described below.

In the above-described embodiment, the gate resistor 61 and the signal line 62 constituting the gate driving unit 29 are provided on the first heat transfer element 83 and the second heat transfer element 84 via the first substrate 85 and the second substrate 86, respectively, but the present invention is not limited thereto. At least one of the gate resistor 61 and the signal line 62 may be provided on the surface of each of the first substrate 85 and the second substrate 86. Further, other circuit elements constituting the gate driving unit 29 may be mounted on the surfaces of the first substrate 85 and the second substrate 86, not limited to the gate resistor 61.

In the above-described embodiment, the power converter 1 is mounted on the vehicle 10, but is not limited thereto, and may be mounted on another device.

The embodiments of the present invention are presented as examples, and are not intended to limit the scope of the invention. These embodiments can be implemented in other various manners, and various omissions, substitutions, and changes can be made without departing from the spirit of the invention. These embodiments and modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

Claims (4)

1. A component module is characterized by comprising:

at least one switching element;

a cooling body disposed on a first surface side in a thickness direction of the switching element;

a heat transfer body that is disposed on a second surface side in a thickness direction of the switching element, is thermally connected to the second surface and the cooling body, and transfers heat from the switching element to the cooling body; and

a drive circuit that drives the switching element,

at least one of circuit elements and signal lines constituting the drive circuit is provided on the heat transfer body,

when viewed from the thickness direction of the switching element, a plate-shaped conductive spacer, a plate-shaped first bus bar, and the heat transfer body are sequentially stacked and arranged on a second surface side in the thickness direction of the switching element, and the switching element, the conductive spacer, the first bus bar, and the heat transfer body are in surface contact with each other.

2. The component module according to claim 1,

the circuit element includes a resistor connected to a control terminal of the switching element,

the resistor is disposed on the heat transfer body.

3. The element module according to claim 1 or 2,

the signal line is disposed on the heat transfer body.

4. The component module according to claim 3,

the signal terminal connected to the signal line is disposed at a position overlapping the heat transfer body in the thickness direction.

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