JP3487235B2 - Semiconductor module pair connection structure and inverter - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting structure of a pair of semiconductor modules and an inverter which constitutes an arm of a three-phase inverter for driving a three-phase motor, for example.

[0002]

2. Description of the Related Art Conventionally, some electric vehicles using a battery as a power source drive and control a three-phase induction motor by a three-phase alternating current obtained by converting the direct current of the battery by a three-phase inverter. Since the forklift includes a traveling motor and a cargo handling motor separately, it is provided with a three-phase inverter for driving the traveling motor and a three-phase inverter for driving the cargo handling motor. The three-phase inverter is, for example, a MOSFE.
The arm consists of a pair of semiconductor switches such as T and IGBT.
It is a three-phase bridge circuit connected in parallel.

Incidentally, semiconductor switches are required to have a large current capacity and a small switching loss. For this reason, in recent years, as a semiconductor switch, a multi-chip module (semiconductor module) in which a plurality of semiconductor chips each having a semiconductor switching element are installed in parallel in a package is used.

As such a semiconductor module, there is a non-insulation type module in which an electrode substrate which also serves as a heat dissipation substrate is provided on the lower surface of a package containing a semiconductor chip. For example, in a semiconductor module in which the semiconductor switching element is a MOSFET, the drain electrode is fixed to the lower surface of the package as a heat dissipation substrate, and the source electrode is provided on the upper surface of the package. In such a semiconductor module, in order to effectively dissipate heat from the electrode substrate, the semiconductor substrate is fixed in a state in which the electrode substrate is in contact with the heat sink via the insulating sheet.

As described above, the forklift is provided with three-phase inverters for driving the traveling motor and for driving the cargo handling motor, respectively. Therefore, as shown in FIGS. 9 and 10, an electric wiring board from the battery and a smoothing capacitor are provided. The common dual inverter structure is adopted.

In this dual inverter structure, a busbar electrode plate 50 connecting each electrode of the battery to each arm of each three-phase inverter is laminated with a positive electrode 51 and a negative electrode 52 with an insulating sheet 53 sandwiched therebetween. Around the busbar electrode plate 50, a semiconductor module pair 54 composed of MOSFETs forming each arm of each three-phase inverter arranged on the upper surface of the heat sink is arranged and connected to the busbar electrode plate 50. Further, by disposing a plurality of smoothing capacitors 55 on the upper surface of the busbar electrode plate 50, the physical capacity of the entire dual inverter structure is reduced.

That is, in the semiconductor module pair 54 which constitutes one arm, the bus bar electrode plate 50 is arranged above one semiconductor module 54a. And FIG.
As shown in FIG. 1, the positive electrode terminal 56 extends downward from the positive electrode plate 51 disposed below the bus bar electrode plate 50.
Is connected to the upper surface of the drain electrode substrate 57 from above the semiconductor module 54a, and the negative electrode terminal 58 extending laterally from the negative electrode 52 is connected to the source electrode from above the other semiconductor module 54b. It is connected to 59. As shown in FIG. 9, the positive electrode terminal 56 is provided in a pair on both sides of the negative electrode terminal 58. In addition, the source electrode 60 of the semiconductor module 54a
And the drain electrode substrate 61 of the semiconductor module 54b are connected to each other by an electrode terminal 62 which is a midpoint of the arm and to which a wiring to the three-phase induction motor is connected. The positive electrode terminal 56 and the electrode terminal 62 are both fixed to the drain electrode substrates 57 and 61 of the semiconductor modules 54a and 54b with mounting screws 63. The gate electrode is not shown.

In the arm thus constructed, the semiconductor module 54a is in the ON state and the semiconductor module 5
When 4b is in the off state, the current supplied from the positive electrode 51 to the semiconductor module 54a via the positive electrode terminal 56 and the drain electrode substrate 57 is the source electrode 60.
And via the electrode terminal 62 to the three-phase induction motor. On the contrary, when the semiconductor module 54a is off and the semiconductor module 54b is on, the current flowing from the three-phase induction motor to the semiconductor module 54b via the electrode terminal 62 and the drain electrode substrate 61 is the source electrode 59 and the negative electrode. Return to battery via terminal 58.

[0009]

By the way, as shown in FIG. 11, in each semiconductor module pair 54, the positive electrode side electrode terminal 56 and the electrode terminal 62 connected to the respective drain electrode substrates 57 and 61 are both connected to each other. Semiconductor modules 54a, 5
4b is fixed to the upper surfaces of the drain electrode substrates 57 and 61 extending outward from the lower surface of the package 64 with mounting screws 63. Therefore, the positive electrode terminal 56 and the electrode terminal 6
2 is provided at a position separated from the package 64 by the amount of the mounting screw 63. Therefore, the gaps existing between the positive electrode terminal 56 and the source electrode 60 and between the electrode terminal 62 and the source electrode 59 are large, and the wiring inductance existing between the respective wirings is large.

As is well known, when the semiconductor module pair 54 is switching-driven at a switching frequency of, for example, about 10 kHz, each semiconductor module 54a, 54
A voltage surge occurs due to the parasitic inductance existing in the internal wiring of b and the wiring connected to the outside. The voltage surge causes switching loss and may further electrically damage the semiconductor modules 54a and 54b. Therefore, like the arm structure described above, the space between the positive electrode terminal 56 and the source electrode 60, and the electrode terminal 62.
If the wiring inductance exists between the semiconductor module 5 and the source electrode 59, the switching loss in each of the semiconductor modules 54a and 54b increases, and further, each semiconductor module 5
It is possible that 4a and 54b are damaged.

Since the electrode terminal 62 is a plate material,
The gap between the portion where the electrode terminal 62 is connected to the source electrode 60 and the busbar electrode plate 50 was large. Therefore, wiring inductance also exists between the busbar electrode plate 50 and the electrode terminals 62. As a result, there has been a problem that the voltage surge and switching loss associated with each switching operation are further increased.

Further, one end of a bus bar for connecting to the three-phase inverter is connected to the electrode terminal 62 which is the middle point of each arm forming the three-phase inverter. At this time, since one end of the bus bar cannot be directly fixed to the electrode terminal 62 located below the bus bar electrode plate 50, a connection terminal (not shown) for fixing one end of the bus bar at the central portion of the adjacent arm is used as an electrode. It was attached to the terminal 62 separately. That is, at the time of assembling the inverter, one end of the connection terminal formed of a plate material is fixed to the electrode terminal 62, and at the end of the assembly, the other end of the connection terminal extended to the central portion of the semiconductor module pair 54 is connected. Secure the busbar. as a result,
Since it is necessary to provide a connection terminal different from the electrode terminal 62 of the semiconductor module pair 54 for each arm, there is a problem that the number of parts and the number of assembling steps increase.

When the bus bar is fixed to the connecting terminal extending from the electrode terminal 62, since each connecting terminal made of a plate material is at the same height as the electrode terminal 62, one end of the bus bar is attached to each connecting terminal. There was a problem that it was not easy to fix the with a mounting screw.

The present invention has been made to solve the above problems, and a first object thereof is to provide a semiconductor module pair capable of reducing the wiring inductance of the semiconductor module pair forming the arm of the inverter. To provide the connection structure of.

The second purpose is, in addition to the first purpose,
It is an object of the present invention to provide a semiconductor module pair connection structure capable of reducing wiring inductance between a semiconductor module and a bus bar electrode plate.

The third purpose is, in addition to the first purpose,
An object of the present invention is to provide a semiconductor module pair connection structure in which it is not necessary to use a connection terminal different from the electrode of the semiconductor module in order to connect the bus bar to the middle point of the arm.

The fourth purpose is, in addition to the first purpose,
An object of the present invention is to provide a connection structure for a semiconductor module pair that enables easy attachment work of a bus bar connected to a middle point of an arm.

[0018]

In order to achieve the first and second objects, the invention according to claim 1 provides a first semiconductor.
The module and the second semiconductor module are provided adjacent to each other.
Is, in the first semiconductor module, to one end surface of the package on which the semiconductor switching element is accommodated, together with the first main current input electrode substrate provided, on the other end surface of the package, the package inside the first main current A first main current input side electrode standing upright on the input side electrode substrate is provided, and in the second semiconductor module, a semiconductor switching element is provided.
Input the second main current to one end of the package containing the child
In addition to the side electrode substrate being provided,
The second main current input side electrode inside the package on the end face.
A second main current input side electrode standing on the substrate is provided, and a first main current input side electrode substrate of the first semiconductor module and a second main current output side electrode of the second semiconductor module are provided. The first main current output side electrode of the first semiconductor module and the second main current input side electrode substrate of the second semiconductor module are connected to the bus bar electrode plate arranged on the other end surface side of the package. in the connection structure of the semiconductor module pairs are connected to each other via a second main current input electrode, the second main current input electrode, the current flowing through the standing portion of the second main current output electrode for,
While being erected on the second main current input electrode on the substrate so as to flow a current that is substantially parallel with close positions, the ribs extending along the generatrix electrode plate to the said bus electrode plate side <br / > It is characterized by being provided.

According to a second aspect of the present invention, in the connection structure for a semiconductor module pair according to the first aspect, a plurality of the ribs are provided so as to extend in a direction of a current flowing through the second main current input side electrode. ing.

In order to achieve the above first and third objects, the invention according to claim 3 provides a first semiconductor module and
And a second semiconductor module are provided adjacent to each other, and
The body module, one end surface of the package on which the semiconductor switching element is accommodated, together with the first main current input electrode substrate provided, on the other end surface of the package, the package inside the first main current input electrode substrate A first main current input side electrode standing upright with respect to the second semiconductor
The module contained a semiconductor switching element
The second main current input side electrode substrate is installed on one end surface of the package.
The package is attached to the other end surface of the package.
Stand inside the cage against the second main current input side electrode substrate.
A second main current input side electrode to be provided, the first main current input side electrode substrate of the first semiconductor module, and the second main current input side electrode substrate.
The second main current output side electrode of the semiconductor module is connected to the bus bar electrode plate arranged on the other end surface side of the package, and the first main current output side electrode of the first semiconductor module and the second main current output side electrode a second main current input electrode substrate of the semiconductor module, in the connection structure of the semiconductor module pairs are connected to each other via a second main current input electrode, the second main current input electrode, said both It is a connection structure of a semiconductor module pair in which a connection terminal portion for fixing one end of a bus bar that connects the middle point of the semiconductor module to the motor side is provided in an integrated structure.

In order to achieve the above first and fourth objects, the invention according to a fourth aspect provides a first semiconductor module and
And a second semiconductor module are provided adjacent to each other, and
The body module, one end surface of the package on which the semiconductor switching element is accommodated, together with the first main current input electrode substrate provided, on the other end surface of the package, the package inside the first main current input electrode substrate A first main current input side electrode standing upright with respect to the second semiconductor
The module contained a semiconductor switching element
The second main current input side electrode substrate is installed on one end surface of the package.
The package is attached to the other end surface of the package.
Stand inside the cage against the second main current input side electrode substrate.
A second main current input side electrode to be provided, the first main current input side electrode substrate of the first semiconductor module, and the second main current input side electrode substrate.
The second main current output side electrode of the semiconductor module is connected to the bus bar electrode plate arranged on the other end surface side of the package, and the first main current output side electrode of the first semiconductor module and the second main current output side electrode In a connection structure of a semiconductor module pair in which a second main current input side electrode substrate of a semiconductor module is connected to each other via a second main current input side electrode, the bus bar electrode plate is the second main current input side. On the electrode
Supported on one side, the second main current input side electrode is provided with a connecting terminal for fixing one end of a bus bar connecting the middle point of both semiconductor modules to the motor side, and the connecting terminal. the mounting surface of the bus bar, and the arrangement side of the semiconductor module to the bus electrode plates on the opposite side, characterized in that provided in the position spaced above the above the bus electrode plate .

According to a fifth aspect of the invention, in the connection structure of the semiconductor module pair according to any one of the first to fourth aspects, the second main current input side electrode is the second main current. It is fixed to the surface of the second main current input side electrode substrate by screwing a mounting screw inserted from the back side of the input side electrode substrate.

According to a sixth aspect of the invention, in the connection structure of the semiconductor module pair according to any one of the first to fifth aspects, a temperature sensor is fixed to the second main current input side electrode. The sensor fixing portion is provided as an integral structure so as to be in close contact with the second main current input side electrode substrate.

The invention described in claim 7 is an inverter in which the semiconductor module pair of each arm is connected by the connection structure of the semiconductor module pair according to any one of claims 1 to 6.

(Operation) According to the invention described in claim 1,
When the first semiconductor module is in the ON state and the second semiconductor module is in the OFF state, the current of the power source flows from the bus bar electrode plate through the first main current input side electrode to the first main current input side electrode substrate, It flows from the current input side electrode substrate to the first main current output side electrode through the semiconductor switching element. Then, it flows from the first main current output side electrode which is the middle point to the motor side. At this time, the current flowing through the upright portion of the first main current input side electrode and the current flowing through the upright portion of the first main current output side electrode flow in parallel and in opposite directions at close positions. As a result, the upright portion of the first main current input side electrode,
The wiring inductance is reduced between the upright portion of the first main current output side electrode. When the first semiconductor module is in the off state and the second semiconductor module is in the on state,
The current from the motor flows to the second main current input side electrode substrate through the second main current input side electrode which is the midpoint, and passes from the second main current input side electrode substrate to the semiconductor switching element to the second main current input side electrode substrate.
It flows to the main current output side electrode. Then, it flows from the second main current output side electrode to the bus bar electrode plate. At this time, the current flowing through the upright portion of the second main current input side electrode and the current flowing through the upright portion of the second main current output side electrode flow in parallel and in opposite directions at close positions. As a result, the wiring inductance in the upright portion of the second main current input side electrode and the upright portion of the second main current output side electrode is reduced. Further, the current flowing through the rib of the second main current input side electrode and the current flowing through the bus bar electrode plate flow in parallel to each other and in opposite directions at positions close to each other. As a result, the wiring inductance between the second main current input side electrode and the bus bar electrode plate is reduced. Therefore,
The wiring inductance of the semiconductor module pair forming the arm is reduced.

According to the invention of claim 2, claim 1
In addition to the function of the invention described in (1), when the current from the motor flows through the second semiconductor module, the current flowing through each rib of the second main current input side electrode and the current flowing through the bus bar electrode plate are close to each other. Flow parallel to each other and in opposite directions. As a result, the wiring inductance between the second main current input side electrode and the bus bar electrode plate is further reduced.

According to the third aspect of the invention, since one end of the bus bar is fixed to the connection terminal portion integrally formed with the second main current input side electrode, it is separately prepared for fixing the bus bar. It is not necessary to assemble the connecting terminal to the second main current input side electrode.

According to the invention described in claim 4, the mounting surface of the connecting terminal for fixing one end of the bus bar is opposite to the side where the semiconductor modules are arranged with respect to the bus bar electrode plate assembled to the semiconductor module pair. Therefore, the bus bar is arranged at a position away from the bus bar electrode plate without forming the bus bar itself to escape from the main current input side electrode and the bus bar electrode plate.

According to the invention of claim 5, in addition to the operation of the invention of any one of claims 1 to 4, the second main current input side electrode substrate is provided with the second main current input. The area for fixing the side electrode is only the area of the second main current input side electrode. Therefore, the installation area of the second semiconductor module is the area of the package plus the area of the second main current input side electrode.

According to the invention of claim 6, in addition to the operation of the invention of any one of claims 1 to 5, the second main component due to the temperature rise of the semiconductor chip of the second semiconductor module is provided. The temperature of the current input side electrode substrate is detected by the temperature detection element fixed to the fixed portion of the second main current input side electrode arranged on the second main current input side electrode substrate. Therefore, a temperature close to the temperature of the semiconductor chip is detected.

According to the invention described in claim 7, the connection structure of the semiconductor module pair of each arm of the inverter functions as the invention described in any one of claims 1 to 6.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in an inverter unit having a dual inverter structure consisting of a pair of three-phase inverters will be described below with reference to FIGS.

As shown in FIGS. 3 and 4, the inverter unit 10 has a dual inverter structure composed of a pair of three-phase inverters 11 and 12.
Is provided on the heat sink H for radiating heat.

The inverter unit 10 includes a plate-shaped busbar electrode plate 13 connected to each electrode of the battery.
Three semiconductor module pairs 14A to 14 that configure the three-phase inverter 11 are provided on one side in the width direction of the busbar electrode plate 13.
C is arranged, and three semiconductor module pairs 15A to 15C forming the three-phase inverter 12 are arranged on the other side. A plurality of smoothing capacitors 16 are arranged on the upper surface of the busbar electrode plate 13.

As shown in FIG. 5, each three-phase inverter 1
1, 1 and 12 are bridge-connected in parallel between each positive electrode and negative electrode of the battery Ba together with each smoothing capacitor 16 by the busbar electrode plate 13. The three-phase inverter 11 is a drive circuit for the traveling motor M1, and each semiconductor module pair 14A to 14C forms a three-phase arm, and the respective middle points thereof are the traveling motor M1.
It is connected to the. The three-phase inverter 12 is a drive circuit for the cargo handling motor M2, and each semiconductor module pair 15A
.About.15C form a three-phase arm, and the respective midpoints thereof are connected to the cargo handling motor M2.

As shown in FIG. 6, the three-phase inverter 11 and the three-phase inverter 12 are arranged such that the three semiconductor module pairs 14A to 14C and 15A to 15C are close to each other. Each semiconductor module pair is
The first semiconductor module 17 connected to the positive electrode side of the battery Ba and the second semiconductor module 1 connected to the negative electrode side.
The two semiconductor modules 17 and 18 are arranged and fixed on the heat sink H in a state of being close to each other.

As shown in FIG. 2, the bus bar electrode plate 13 has a positive electrode 19 connected to the positive electrode of the battery Ba,
The negative electrode 20 connected to the negative electrode of the battery Ba is laminated with the insulating sheet 13a interposed. That is, the busbar electrode plate 13 includes the positive electrode 19, the negative electrode 20, and the insulating sheet 13a. The positive electrode 19 is a semiconductor module pair 14A to 14C, 1
The smoothing capacitors 16 are arranged on the 5A to 15C sides and on the negative electrode 20. As shown in FIGS. 3 and 4, the busbar electrode plate 13 is provided such that its end portion in the width direction is located between the first semiconductor module 17 and the second semiconductor module 18.

As shown in FIG. 2, each semiconductor module 17, 18 has a MOSF as a semiconductor switching element.
This is a multi-chip module in which a plurality of semiconductor chips 21 on which ETs are formed are arranged in a package 22, and is equivalent to one MOSFET as a whole. Package 22
Is made of synthetic resin, and the direction in which the plate-shaped semiconductor chips 21 are arranged in one row is the longitudinal direction. Therefore, in FIG. 2, only one semiconductor chip 21 is shown.

As shown in FIG. 2, the first semiconductor module 17 includes a first drain electrode substrate 23 as a first main current input side electrode substrate on the lower surface of the package 22 and is exposed on the upper surface of the package 22. Three first source electrodes 24 as first main current output side electrodes are provided.
The first drain electrode substrate 23 is a substrate for heat dissipation of each semiconductor chip 21, and each semiconductor chip 21 is a package 2
2 is installed on the upper surface of the first drain electrode substrate 23. Note that the upper surface of the package 22, is provided Gate electrode G.

The first drain electrode substrate 23 includes a fixing portion 23a extending from the lower surface of the package 22 in one of the widthwise directions by a predetermined width. The first source electrodes 24 have the same shape and are made of a plate material having a “U” -shaped cross section. The first source electrode 24 has the upper horizontal portion 24a.
Is arranged on the upper surface of the package 22, and a vertical portion 24b as a standing portion and a lower horizontal portion 24c are arranged inside the package 22. In each of the first source electrodes 24, the vertical portion 24b is arranged vertically to the first drain electrode substrate 23, and is arranged in a position close to the fixed portion 23a of the first drain electrode substrate 23, They are arranged in a line so that the width direction is the longitudinal direction of the package 22.

Similarly, the second semiconductor module 18 includes the second drain electrode substrate 25 as the second main current input side electrode substrate on the lower surface of the package 22 and the second main current exposed on the upper surface of the package 22. Three second source electrodes 26 are provided as output side electrodes. The second drain electrode substrate 25 is a heat dissipation substrate for each semiconductor chip 21, and each semiconductor chip 21 is installed on the upper surface of the second drain electrode substrate 25 in the package 22.
A gate electrode G is provided on the upper surface of the package 22.

The second drain electrode substrate 25 includes a fixing portion 25a extending from the lower surface of the package 22 in one of the width directions by a predetermined width. Each second source electrode 26 has the same shape and is made of a plate material having a U-shaped cross section. The second source electrode 26 has the upper horizontal portion 26a.
Are arranged on the upper surface of the package 22, and a vertical portion 26b as a standing portion and a lower horizontal portion 26c are arranged inside the package 22. In each of the second source electrodes 26, the vertical portion 26b is arranged vertically to the second drain electrode substrate 25 and is arranged in a position close to the fixed portion 25a of the second drain electrode substrate 25, They are arranged in a line so that the width direction is the longitudinal direction of the package 22.

Both semiconductor modules 17 and 18
Is in a state where the first or second drain electrode substrate 23, 25 is brought into close contact with the upper surface of the heat sink H with the insulating sheet 27 interposed, and the first or second drain electrode substrate 23, 2
5, the fixing portions 23a and 25a of the No. 5 are arranged on the heat sink H. A circuit board 28 provided with a free wheeling diode and a snubber circuit is fixed to each of the semiconductor modules 17 and 18.

Further, both semiconductor modules 17 and 18 include
As shown in FIGS. 1 and 2, a first drain electrode 29 for bridge connection to the battery Ba and a second drain electrode 30 as a main current input side electrode are provided. The first drain electrode 29 serves as the first semiconductor module 1
The first drain electrode substrate 23 of No. 7 is connected to the positive electrode side electrode 19, and the second drain electrode 30 is the first semiconductor module 1
7 of the first source electrodes 24 to the second semiconductor module 18
Of the second drain electrode substrate 25. A negative electrode terminal 20 a extending outward from the negative electrode 20 is connected to each second source electrode 26 of the second semiconductor module 18.

As shown in FIGS. 1 and 2, the first drain electrode 29 is a block body formed in a "U" shape in a front view, and on the fixing portion 23a of the first drain electrode substrate 23, The both vertical portions 29a are provided so as to be arranged at both ends of the package 22 of the semiconductor module 17 in the longitudinal direction. The first drain electrode 29 is provided such that both vertical portions 29a thereof are parallel to the vertical portions 24b of the respective first source electrodes 24 and are in the state of being as close as possible to the respective first source electrode 24 sides. There is. Each vertical portion 29a includes
As shown in FIG. 3, positive side electrode terminals 19 a extending from the positive electrode side electrode 19 are connected to the upper surface thereof.

The fixed portion 2 of the first drain electrode substrate 23
3a is formed such that the area of its upper surface is large enough to fix the first drain electrode 29 to the upper surface. Then, the first drain electrode 29 is fixed to the upper surface of the fixing portion 23a by screwing the mounting screw 31 inserted from the lower surface of the first drain electrode substrate 23.

As shown in FIGS. 1, 2, and 7, the second drain electrode 30 is a block body formed in an “L” shape in a side view, and is a fixing portion 25 of the second drain electrode substrate 25.
The horizontal portion 30a of the first semiconductor module 1
It is provided so as to extend above the respective first source electrodes 24 of No. 7. The second drain electrode 30 has a horizontal portion 30a.
Are formed so as to extend between the vertical portions 29a of the first drain electrode 29 and extend toward the first source electrode 24 side. The vertical portion 30b of the second drain electrode 30 is
It is provided in a state of being parallel to the vertical portion 26b of each second source electrode 26, and in a state of being as close as possible to each second source electrode 26 side.

The fixed portion 2 of the second drain electrode substrate 25
5a is formed such that the area of its upper surface is large enough to fix the second drain electrode 30 to the upper surface. Then, the second drain electrode 30 is fixed to the upper surface of the fixing portion 25a by screwing the mounting screw 31 inserted from the lower surface of the second drain electrode substrate 25.

Also, the horizontal portion 30a of the second drain electrode 30.
Is provided with a plurality of ribs 32a and 32b on the busbar electrode plate 13 side so as to extend along the busbar electrode plate 13 and in the direction of the current flowing through the second drain electrode 30. The upper surfaces of the ribs 32a and 32b are provided so as to be close to the lower surface of the positive electrode 19.

Further, the second drain electrode 30 has a structure shown in FIG.
As shown in FIGS. 4 and 7, a connection terminal portion 33 for fixing one end of the bus bar B that connects the midpoints of both semiconductor modules 17 and 18 to the motors M1 and M2 is provided as an integral structure. As shown in FIG. 4, the connection terminal portion 33 has a mounting surface 33a for fixing one end of the bus bar B in contact with the bus bar electrode plate 13 on which the semiconductor modules 17, 18 are arranged. It is provided so as to be located on the opposite side.

As shown in FIGS. 7 and 8, in the vertical portion 30b of the second drain electrode 30, a sensor for fixing a thermistor T as a temperature sensor for detecting the temperature of the semiconductor module 17 at the lower portion of the lateral surface thereof. The fixing portion 34 is formed as an integral structure by extension. As shown in FIG. 8, the sensor fixing portion 34 is provided so as to be in close contact with the upper surface of the fixing portion 23 a of the first drain electrode substrate 23. Sensor fixing part 34
On the upper surface of the thermistor T, the rotation of the thermistor T fixed by the mounting screw 35 is regulated so that the thermistor T can prevent the
A restricting piece 34a is formed so as not to come into contact with.

As shown in FIGS. 1, 2, and 4, the second drain electrode 30 is provided with an insulating sheet 13a. The insulating sheet 13a is provided so as to insulate the second drain electrode 30 and the positive electrode 19 from each other. The insulating sheet 13a includes sleeve pieces 37a provided in the longitudinal direction thereof.
Are interposed between the vertical portions 29a of the first drain electrode 29 and the second drain electrode 30 to be fixedly held in the longitudinal direction. Further, in the insulating sheet 13a, the sleeve piece 37b provided on one side in the width direction is interposed between each first source electrode 24 of the first semiconductor module 17 and the circuit board 28, and provided on the other side. Cuffs 37c
However, the second drain electrode 30 and the second semiconductor module 1
It is fixedly held in the width direction by being interposed between the eight packages 22.

Then, the semiconductor module pairs 14A to 14C and 15A to 15C of the three-phase inverters 11 and 12, respectively.
Have the same configuration. Three-phase inverter 11
In the above, a drive control circuit (not shown) supplies a control signal for switching driving so that the semiconductor module pairs 14A to 14C of each arm are alternately turned on / off to each gate electrode G in a predetermined switching sequence. The three-phase inverter 11 supplies the traveling motor M1 with a three-phase alternating current having a voltage, a frequency and a phase according to the control signal supplied to each of the semiconductor module pairs 14A to 14C. Similarly, the three-phase inverter 12 performs a switching operation according to a control signal supplied from a cargo handling control circuit (not shown), and generates a three-phase alternating current having a voltage, a frequency, and a phase corresponding to the control signal from the cargo handling motor M.
Supply to 2.

Next, the operation of the connecting structure of the semiconductor module pair forming the arm of the inverter constructed as described above will be described. When the first semiconductor module 17 is on and the second semiconductor module 18 is off, the current of the battery Ba flows from the positive electrode side electrode 19 through the first drain electrode 29 to the first drain electrode substrate 23, and the first drain From the electrode substrate 23 to each semiconductor chip 21
Through each first source electrode 24. Then, it flows from each first source electrode 24 to the traveling motor M1 side via the bus bar B fixed to the second drain electrode 30. At this time, the current flowing through the vertical portion 29a of the first drain electrode 29 and the current flowing through the vertical portion 24b of each of the first source electrodes 24 flow in parallel to each other and in opposite directions at close positions. As a result, due to the mutual induction action, the vertical portion 29a of the first drain electrode 29 and each first source electrode 2
Wiring inductance in the vertical portion 24b of No. 4 is reduced.

When the first semiconductor module 17 is off and the second semiconductor module 18 is on, the current from the traveling motor M1 side passes through the bus bar B, the second drain electrode 30, and the second drain. The semiconductor chip 21 flows from the second drain electrode substrate 25 to each of the semiconductor chips 21.
Through each second source electrode 26. Then, it flows from each second source electrode 26 to the negative electrode 20. At this time, the current flowing through the vertical portion 30b of the second drain electrode 30 and the current flowing through the vertical portion 26b of each of the second source electrodes 26 flow in parallel to each other and in opposite directions at close positions. As a result, due to the mutual induction effect, the wiring inductance between the vertical portion 30b of the second drain electrode 30 and the vertical portion 26b of each second source electrode 26 is reduced.

Further, each rib 32 of the second drain electrode 30
The currents flowing through the a and 32b and the current flowing through the negative electrode 20 flow parallel to each other and in opposite directions at positions close to each other. As a result, the wiring inductance between the second drain electrode 30 and the negative electrode 20 is reduced.

Therefore, the wiring inductance of the semiconductor module pair forming the arm is reduced. In addition, the semiconductor module pair 15 forming each arm of the three-phase inverter 12
A to 15C also have the same effect.

According to the wiring structure of the semiconductor module pair forming the arm of the inverter of the present embodiment described in detail above, there are the following actions and effects. (1) In the first semiconductor module 17, the first drain electrode 29 provided on the first drain electrode substrate 23.
Each vertical portion 29a of the above is made to be closest to the vertical portion 24b of each first source electrode 24 provided in the package 22 in a parallel state. Similarly, in the second semiconductor module 18, the vertical portion 30b of the second drain electrode 30 provided on the second drain electrode substrate 25 is the vertical portion 2 of each second source electrode 26 provided in the package.
6b was made to be as close to the 6b as possible in a parallel state.

Therefore, the wiring inductance in each portion is reduced due to the mutual induction action between the portions that are close to each other in the parallel state, so that the semiconductor modules 17 and 18 are switched during the switching operation. The voltage surge generated at 17 and 18 is suppressed, and the switching loss due to the voltage surge is suppressed.

(2) The second drain electrode 30 is provided with ribs 32a and 32b extending along the negative electrode 20 on the upper surface of the horizontal portion 30a extending parallel to the negative electrode 20.
Therefore, the current flowing through the negative electrode 20 and the current flowing through the ribs 32a and 32b of the second drain electrode 30 flow in opposite directions at positions close to each other, and the mutual induction action between the two causes the negative electrode 20 And the second drain electrode 30
The wiring inductance at and is reduced. as a result,
The surge voltage generated by the switching operation in the semiconductor module 18 can be further suppressed, and the switching loss due to the surge voltage can be further suppressed.

(3) The second drain electrode 30 is provided with a plurality of ribs 32a and 32b so as to extend in the direction of the current flowing through the second drain electrode 30. Therefore, each rib 3
The currents flowing through 2a and 32b and the current flowing through the negative electrode 20 flow in parallel and in opposite directions at positions close to each other, so that the second drain electrode 30 and the negative electrode 20
The wiring inductances at and are further reduced. As a result, surge voltage and switching loss can be further suppressed.

(4) Second drain electrode 30 which is the midpoint
A connecting terminal portion 33 for fixing one end of the bus bar B connected to the motors M1 and M2 is provided in the unit.
Therefore, one end of the bus bar B is fixed to the connecting terminal portion 33 provided integrally with the second drain electrode 30 of the second semiconductor module 18, so that a connecting terminal separately prepared for fixing the bus bar B is used. It is not necessary to assemble the second drain electrode 30. As a result, in order to connect the bus bar B to the midpoint of the arm, it is not necessary to use an electrode for connecting the semiconductor module pair 14A and a connection terminal different from the electrode.

(5) In the connection terminal portion 33 provided on the second drain electrode 30, the mounting surface 33a of the bus bar B is located on the side opposite to the side where the semiconductor module pair 14A is arranged with respect to the bus bar electrode plate 13. I was prepared to do. Therefore, the bus bar B can be attached to the attachment surface 33a that is located above the busbar electrode plate 13 and can be easily attached.

(6) First of the first semiconductor module 17
The drain electrode substrate 23 is provided with a fixing portion 23a having a size necessary for fixing the first drain electrode 29 formed of a block body to the upper surface, and a mounting screw inserted from the lower surface of the fixing portion 23a. The first drain electrode 29 is fixed to the upper surface of the fixing portion 23a by screwing 31 together.

Therefore, a second drain electrode substrate 25 is formed on the second drain electrode substrate 25.
Since the area for fixing the drain electrode 30 is only the area of the second drain electrode 30, the installation area of the second semiconductor module 18 is equal to the area of the package 22 plus the area of the second drain electrode 30. OK. For this reason,
A convex portion for inserting the mounting screw 31 is provided on the lower portion of the side surface of the first drain electrode 29 having the same shape, and the mounting screw 31 is screwed into the first drain electrode 29 from the upper surface of the convex portion to form the first drain. The electrode 29 is used as the first drain electrode substrate 23.
The first drain electrode substrate 23, as compared with the case where it is fixed to
The area of can be reduced by the area occupied by the convex portion. Therefore, the installation area of the entire inverter unit 10 having the dual inverter structure can be reduced.

The same effect can be obtained even if the second drain electrode 30 is fixed by screwing the mounting screw inserted from the upper end surface thereof to the fixing portion 25a of the second drain electrode substrate 25. However, as compared with the case where the attachment screw is inserted into the long vertical portion 30b of the second drain electrode 30 with respect to the second drain electrode substrate 25 and screwed into the second drain electrode substrate 25, the assembling work is easier. is there.

(7) On the second drain electrode 30, the sensor fixing portion 34 for fixing the thermistor T for detecting the temperature of the semiconductor chip 21 is provided on the second drain electrode substrate 25.
It was provided as an integral structure so as to be in close contact with the upper surface of the. Therefore, since the temperature of the second drain electrode substrate 25 due to the temperature rise of the semiconductor chip 21 of the second semiconductor module 18 is detected, the temperature close to the temperature of the semiconductor chip 21 is detected.
As a result, the temperature closer to the temperature of the semiconductor chip 21 can be detected as compared with the case where the thermistor T is provided on the heat sink H.

(8) The insulating sheet 13a interposed between the busbar electrode plate 13 and the second drain electrode 30 of each semiconductor module pair 14A is provided with sleeve pieces 37a extending downward at both longitudinal ends. By disposing each sleeve piece 37a between the second drain electrode 30 and each vertical portion 29a of the first drain electrode 29 disposed on both sides of the second drain electrode 30, the insulating sheet 13a is elongated. I tried not to move in the direction. Therefore, the semiconductor module pair 14A side,
Alternatively, it is not necessary to provide a structure for fixing the insulating sheet 13a on the busbar electrode plate 13 side. Further, when assembling the three-phase inverters 11 and 12, it is only necessary to place the insulating sheet 13a at a predetermined position, which facilitates the assembling work.

Embodiments other than the above-described embodiment embodying the present invention will be listed below as another example. The second drain electrode 30 is not limited to the one in which the connection terminal portion 33 is provided as an integrated structure, but each first source electrode 24
The second drain electrode substrate 25 may be connected to the drain electrode. In this case, the midpoint output terminal having the connecting terminal portion is assembled and fixed to the drain electrode.

The first source electrode 24 and the second drain electrode substrate 25 are not provided with the connecting terminal portion 33 as an integrated structure.
The drain electrode formed only by connecting to and may be formed by die casting of aluminum or the like, and ribs may be provided on the bus bar electrode plate 13 side. Also in this case, the wiring inductance can be reduced in the negative electrode 20 and the drain electrode.

In the semiconductor module, the main current input side electrode substrate for the main current to be supplied to the motor is provided on one end surface of the package in which the semiconductor chip having the semiconductor switching element is housed, and the package is provided on the other end surface. The main current output side electrode standing upright with respect to the main current input side electrode substrate may be provided inside, and the semiconductor switching element is not limited to the MOSFET, but may be a bipolar transistor, an IGBT or the like. Good.

The temperature sensor is not limited to the thermistor T and may be a transistor temperature sensor, a platinum temperature sensor or the like as long as it is a contact type. The connection structure of the semiconductor module pair of the present invention is the semiconductor module pair 14A to 14C and 15A to 1 which configure the three-phase inverters 11 and 12 of the dual inverter structure.
Not only the connection structure in 5C, but the main current input side electrode substrate and the main current output of each semiconductor module with respect to the bus bar electrode plate arranged on the side of each main current output side electrode of the adjacent semiconductor module pair. It suffices as long as it has a connection structure of a semiconductor module pair to which the side electrodes are connected. Therefore, for example, the connection structure of each semiconductor module pair of one three-phase inverter may be used, or the connection structure of the semiconductor module pair of a single-phase inverter may be used.

Below, in addition to the inventions described in the claims, the technical idea grasped from the above-mentioned respective embodiments and respective other examples will be described together with their effects. (1) In the invention according to claim 3, the connection terminal portion is provided such that a mounting surface of the bus bar is located on a side opposite to a side where the semiconductor modules are arranged with respect to the bus bar electrode plate. There is. According to such a configuration, in order to connect the bus bar to the midpoint of the semiconductor module pair, it is not necessary to use a connecting terminal different from the electrode for connecting the semiconductor module pair, and the fixing work of the bus bar is easy. Can be done.

(2) In the invention according to any one of claims 1 to 6, an insulating sheet is provided between the first main current input side electrode and the bus bar electrode plate. The sleeve pieces (37a, 37b, 37c) that engage with the first main current input side electrodes are provided on both ends of the insulating sheet. According to such a configuration, each sleeve piece is first
Since the insulating sheet is held at a predetermined position by engaging with the main current input side electrode, it is not necessary to provide a structure for holding the insulating sheet on the bus bar electrode side or the semiconductor module side. In addition, since the insulating sheet only needs to be placed at a predetermined position when the busbar electrode plate is assembled, the assembling work becomes easy.

[0075]

According to the invention described in claims 1, 2, or 5, 6, 7, the wiring inductance of the semiconductor module pair can be reduced, and the surge voltage and the switching loss can be reduced.

According to the invention described in claim 2 or claim 5, 6, 7, it is possible to further reduce the wiring inductance of the semiconductor module pair and further reduce the surge voltage and the switching loss.

According to the third or fifth, sixth, seventh invention, in order to connect the bus bar to the midpoint of the arm, it is necessary to use an electrode for connecting the semiconductor module and a different connecting terminal. Absent.

According to the invention described in claim 4 or claim 5, 6, 7, it is possible to easily carry out the work of attaching the bus bar connected to the midpoint of the arm. According to the invention described in claims 5 to 7, the installation area of the semiconductor module pair can be made as small as possible.

According to the sixth or seventh aspect of the present invention, compared to the case where the temperature detecting element is provided on the heat sink,
It is possible to detect a temperature close to the temperature of the semiconductor chip.

[Brief description of drawings]

FIG. 1 is a perspective view showing a semiconductor module pair forming an arm.

FIG. 2 is a side view of a semiconductor module pair.

FIG. 3 is a plan view of an inverter unit.

FIG. 4 is a side view of the inverter unit.

FIG. 5 is a circuit diagram of an inverter unit.

FIG. 6 is a plan view of each inverter.

FIG. 7 is a perspective view of a second drain electrode.

FIG. 8 is a partial plan view of a semiconductor module pair showing a fixing portion.

FIG. 9 is a schematic plan view of a conventional inverter unit.

FIG. 10 is a schematic side view of the same inverter unit.

FIG. 11 is a side view of a semiconductor module pair showing a connection structure.

[Explanation of symbols]

10 ... dual inverter, 11 ... three-phase inverter, 1
2 ... Three-phase inverter, 13 ... Busbar electrode plate, 13a ... Insulating sheet which comprises a busbar electrode plate, 14A-14C, 15A
˜15C ... Semiconductor module pair, 17 ... Semiconductor module, 18 ... Semiconductor module, 19 ... Positive electrode side electrode constituting bus bar electrode plate, 20 ... Same negative electrode side electrode, 21 ... Semiconductor chip as semiconductor switching element, 22 ... Package, 23 ... first drain electrode substrate as a first main current input electrode substrate, 24 ... first source electrode as a first main current output electrode, 25 ... second drain electrode as a second main current input electrode substrate Substrate, 26 ... Second source electrode as second main current output side electrode, 26b ... Vertical part as standing portion, 30 ... Second drain electrode as second main current input side electrode, 31 ... Mounting screw, 32a , 32b ... ribs, 33
... connection terminal portion, 33a ... mounting surface, 34 ... sensor fixing portion, B ... bus bar, M1 ... traveling motor, M2 ... cargo handling motor, T ... thermistor as temperature sensor.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 25/07 H01L 25/18

Claims (7)

(57) [Claims] 1. A first semiconductor module and a second semiconductor module.
Joules are provided adjacent to each other, and in the first semiconductor module
Is one end surface of the package on which the semiconductor switching element is accommodated, together with the first main current input electrode substrate provided, on the other end surface of the package, with respect to the first main current input electrode substrate within the package first main current input electrode erected provided Te, the second semiconductor module
Of the package containing the semiconductor switching element
When the second main current input side electrode substrate is provided on one end face
On the other end of the package, inside the package
A second main body standing upright on the second main current input side electrode substrate
A current input side electrode is provided, and a first main current input side electrode substrate of the first semiconductor module and a second main current output side electrode of the second semiconductor module are arranged on the other end surface side of the package. While being connected to the busbar electrode plate, the first main current output side electrode of the first semiconductor module and the second main current input side electrode substrate of the second semiconductor module are connected via the second main current input side electrode. In the connection structure of a pair of semiconductor modules connected to each other, the second main current input side electrode is substantially parallel to a current flowing in the standing portion of the second main current output side electrode at a close position. Is erected on the second main current input side electrode substrate so as to flow a current, and is provided on the bus bar electrode plate side .
Connection structure of the semiconductor module pair having a rib extending along the generatrix electrode plate. 2. A connecting structure of a semiconductor module pairs according to claim 1, wherein the ribs are connected to the semiconductor module pairs are provided in plural so as to extend in the direction of the current flowing through the second main current input electrode Construction. 3. A first semiconductor module and a second semiconductor module.
Joules are provided adjacent to each other, and in the first semiconductor module
Is one end surface of the package on which the semiconductor switching element is accommodated, together with the first main current input electrode substrate provided, on the other end surface of the package, with respect to the first main current input electrode substrate within the package first main current input electrode erected provided Te, the second semiconductor module
Of the package containing the semiconductor switching element
When the second main current input side electrode substrate is provided on one end face
On the other end of the package, inside the package
A second main body standing upright on the second main current input side electrode substrate
A current input side electrode is provided, and a first main current input side electrode substrate of the first semiconductor module and a second main current output side electrode of the second semiconductor module are arranged on the other end surface side of the package. While being connected to the busbar electrode plate, the first main current output side electrode of the first semiconductor module and the second main current input side electrode substrate of the second semiconductor module are connected via the second main current input side electrode. In the connection structure of a pair of semiconductor modules connected to each other, a connection terminal portion for fixing one end of a bus bar connecting the middle point of both semiconductor modules to the motor side on the second main current input side electrode. A connection structure of a semiconductor module pair in which is provided as an integrated structure. 4. A first semiconductor module and a second semiconductor module.
Joules are provided adjacent to each other, and in the first semiconductor module
Is one end surface of the package on which the semiconductor switching element is accommodated, together with the first main current input electrode substrate provided, on the other end surface of the package, with respect to the first main current input electrode substrate within the package first main current input electrode erected provided Te, the second semiconductor module
Of the package containing the semiconductor switching element
When the second main current input side electrode substrate is provided on one end face
On the other end of the package, inside the package
A second main body standing upright on the second main current input side electrode substrate
A current input side electrode is provided, and a first main current input side electrode substrate of the first semiconductor module and a second main current output side electrode of the second semiconductor module are arranged on the other end surface side of the package. While being connected to the busbar electrode plate, the first main current output side electrode of the first semiconductor module and the second main current input side electrode substrate of the second semiconductor module are connected via the second main current input side electrode. In the connection structure of a pair of semiconductor modules connected to each other, the busbar electrode plate is located above the second main current input side electrode.
The second main current input side electrode supported is provided with a connection terminal for fixing one end of a bus bar connecting the middle point of both semiconductor modules to the motor side, and the connection terminal is The mounting surface of the bus bar is opposite to the side where the semiconductor modules are arranged with respect to the bus bar electrode plate.
In, the connection structure of the semiconductor module pairs are provided in position spaced above the above the bus electrode plate. 5. The semiconductor module pair connection structure according to claim 1, wherein the second main current input side electrode is provided on a back surface of the second main current input side electrode substrate. A connection structure of a semiconductor module pair fixed to the surface of the second main current input side electrode substrate by screwing a mounting screw inserted therethrough. 6. The semiconductor module pair connection structure according to claim 1, wherein the second main current input electrode has a sensor fixing portion for fixing a temperature sensor, A connection structure of a semiconductor module pair provided as an integral structure so as to be in close contact with the second main current input side electrode substrate. 7. An inverter in which the semiconductor module pair of each arm is connected by the connection structure of the semiconductor module pair according to claim 1. Description: