JP2010016925A - Power semiconductor module and semiconductor power conversion device equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power semiconductor module for suppressing vibration of current and voltage and supplying stable output, and to provide a semiconductor power conversion device. <P>SOLUTION: The power semiconductor module is provided with: a semiconductor element including a switching element 41a and configuring one arm; a positive pole conductor 61 connected to the positive pole side of the semiconductor element; an electrode conductor 63 connected to the negative pole side of the semiconductor element; an input/output terminal 76a provided on the switching element; and an emitter sense terminal 78a provided in a position other than the switching element and driving the switching element. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power semiconductor module and a semiconductor power conversion device including the same.

  In general, an electric vehicle and a hybrid vehicle include an inverter device as a power semiconductor device that converts direct current into alternating current and supplies the motor to a motor. For example, a three-phase inverter device has three power semiconductor modules corresponding to the U phase, the V phase, and the W phase. Such an in-vehicle semiconductor power conversion device must be downsized, reduced in cost, and improved in cooling efficiency. In order to achieve this purpose, the power semiconductor module that is a main component of the semiconductor power conversion device is required. Miniaturization, cost reduction, and improvement in cooling efficiency are important.

  For example, according to the semiconductor power conversion device disclosed in Patent Document 1, the power semiconductor module is joined to the first conductor, the second conductor, and the third conductor, which are each formed of a conductive metal, and these conductors. And a cooler having a joint surface. An IGBT (insulated gate bipolar transistor), which is a semiconductor element constituting a one-phase upper arm, and the positive electrode side of the diode are joined to the first conductor. The second conductor is joined to the IGBT constituting the lower arm of one phase and the negative electrode side of the diode. The third conductor is disposed between the first conductor and the second conductor, and is joined to the negative electrode side of the IGBT and the diode constituting the upper arm, and the positive electrode side of the IGBT and the diode constituting the lower arm. . The first conductor and the second conductor function as a positive electrode and a negative electrode, and the third conductor functions as an AC output electrode.

  Each IGBT is provided with a plurality of input / output terminals such as a gate terminal and an emitter sense terminal. The first to third conductors are arranged in the cooler so that the joint surface with the semiconductor element is not parallel to the joint surface between the cooler and the conductor.

With such a configuration, a power semiconductor module and a semiconductor power conversion device with improved cooling efficiency and manufacturability are provided.
JP 2007-68302 A

  In the power semiconductor module configured as described above, a switching element such as an IGBT is sandwiched between a plurality of conductors, and both polar surfaces of the switching element are joined to the conductor, and the emitter sense terminal serves as the switching element. Is provided. In this case, the emitter sense position is near the surface of the emitter electrode of the switching element, and the inductance on the emitter side is substantially zero. Therefore, a phenomenon occurs in which the current and voltage of the switching element vibrate when the switching element is driven. When such current and voltage oscillations occur, it becomes difficult to stably drive a motor or the like by the power semiconductor module.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a power semiconductor module and a semiconductor power conversion device that can suppress oscillation of current and voltage and supply a stable output.

  A power semiconductor module according to an aspect of the present invention includes a semiconductor element including a switching element and constituting one arm, a positive conductor bonded to the positive electrode side of the semiconductor element, an electrode conductor bonded to the negative electrode side of the semiconductor element, An input / output terminal provided on the switching element; and an emitter sense terminal provided at a position other than the switching element for driving the switching element.

  A power semiconductor module according to another aspect of the present invention includes a first semiconductor element including a first switching element and constituting one arm, a second semiconductor element including a second switching element and constituting another arm, and the first semiconductor element. A first conductor bonded to the positive electrode side of the semiconductor element; a second conductor bonded to the negative electrode side of the second semiconductor element; and the first semiconductor element disposed between the first conductor and the second conductor. A third conductor joined to the negative electrode side and the positive electrode side of the second semiconductor element, a plurality of input / output terminals provided in the first switching element and the second switching element, and other than the first and second switching elements And an emitter sense terminal for driving the first and second switching elements.

  A semiconductor power conversion device according to an aspect of the present invention includes the power semiconductor module, a drive circuit that drives the plurality of power semiconductor modules, and a control circuit that controls the plurality of power semiconductor modules.

  According to the said structure, the electric power semiconductor module which can suppress the vibration of an electric current and a voltage, and can supply the stable output, and a semiconductor power converter device can be provided.

Hereinafter, an embodiment in which a semiconductor power conversion device including a power semiconductor module according to an embodiment of the present invention is applied to an inverter device will be described with reference to the drawings.
FIG. 1 shows an equivalent circuit of the inverter device. As shown in FIG. 1, the inverter device 10 is configured as, for example, a U-phase, V-phase, and W-phase three-phase inverter, and is configured to supply power to the motor 12 as a load target. . The inverter device 10 is integrally provided with an inverter circuit that supplies power to the motor 12.

  The inverter device 10 includes three power semiconductor modules 16, 18, and 20 corresponding to the U-phase, V-phase, and W-phase, respectively, and a smoothing that smoothes the DC voltage supplied from the DC power source, for example, the battery 22 to the power semiconductor module. Current detectors 28a, 28b, 28c for detecting the current flowing to the motor 12 via the capacitor 24 and the three-phase output connection conductor 26; current information detected by the current detector; and a voltage applied to the smoothing capacitor 24 The control unit 32 that controls the power semiconductor modules 16, 18, and 20 based on the above, and the drive having a drive circuit for driving the gate of the semiconductor element of the power semiconductor module described later based on the control signal of the control unit 32 And a substrate 34. The driving substrate 34 is provided with driving ICs 36 for driving the semiconductor elements in a one-to-one correspondence with the semiconductor elements. That is, in this circuit, six driving ICs 36 are provided. Further, below the power semiconductor modules 16, 18, 20 and the smoothing capacitor 24, a cooler (not shown) such as a heat sink for cooling them is provided.

Hereinafter, the power semiconductor modules 16, 18, and 20 will be described in detail. Since the power semiconductor modules 16, 18, and 20 have the same configuration, one power semiconductor module 16 will be described as a representative.
FIG. 2 is a perspective view showing the power semiconductor module 16 with the cover removed, and FIG. 3 is a plan view of the power semiconductor module.

  As shown in FIGS. 1, 2, and 3, the power semiconductor module 16 includes a first semiconductor element that constitutes the U-phase upper arm in the inverter circuit, here, an IGBT 41 a and a diode 51 a that are first switching elements, an inverter Second semiconductor element constituting lower arm of U phase in circuit, here, IGBT 41b and diode 51b functioning as second switching element, first conductor 61, second conductor 62, third conductor 63, sheet-like insulator 66, a heat sink 67 functioning as a base is provided.

  The IGBTs 41a and 41b and the diodes 51a and 51b are, for example, semiconductor chips having a size of about 10 mm square. Each of the diodes 51a and 51b is connected in antiparallel to each of the IGBTs 41a and 41b.

  The first, second, and third conductors 61, 62, and 63 are each formed of a conductive metal in an elongated rod shape having both axial end portions, for example, a prism shape. The first conductor 61, the second conductor 62, and the third conductor 63 have the same length and are formed to have substantially the same diameter.

  One side surface of the first conductor 61 forms a first joint surface 61a, and the other side surface orthogonal to the one side surface forms a second joint surface. The first joining surface 61a of the first conductor 61 is electrically and mechanically joined to the positive side (collector and cathode, respectively) of the IGBT 41a and the diode 51a constituting the upper arm. The first conductor 61 constitutes a DC positive conductor common to the first semiconductor element. On the first joint surface 61a, the IGBT 41a and the diode 51a are arranged side by side along the longitudinal direction (center axis direction) of the first conductor 61.

  One side surface of the second conductor 62 forms a first joint surface 62a, and the other side surface orthogonal to the one side surface forms a second joint surface. The first joining surface 62a of the second conductor 62 is joined to the negative side (emitter and anode, respectively) of the IGBT 41b and the diode 51b constituting the lower arm. Accordingly, the second conductor 62 is electrically and mechanically connected to the negative electrode of the IGBT 41b and the diode 51b. The second conductor 62 constitutes a direct current negative electrode conductor common to the second semiconductor element. On the first joint surface 62a, the IGBT 41b and the diode 51b are arranged side by side along the longitudinal direction (center axis direction) of the second conductor 62.

  The second conductor 62 is arranged in parallel with the first conductor 61 with a gap therebetween. The first joint surface 61a of the first conductor 61 and the first joint surface 62a of the second conductor 62 face each other in parallel with a gap. The second joint surface of the first conductor 61 and the second joint surface of the second conductor 62 are located side by side on the same plane.

  As shown in FIGS. 2 and 3, the third conductor 63 is arranged in parallel with the first and second conductors with a gap between the first conductor 61 and the second conductor 62. The third conductor 63 is arranged such that one end portion in the axial direction thereof is aligned with one end portion in the axial direction of the first and second conductors 61 and 62. The third conductor 63 is disposed such that the other end in the axial direction thereof is aligned with the other end in the axial direction of the first and second conductors 61 and 62. The third conductor 63 has a central axis C along the longitudinal direction thereof, and the first, second, and third conductors 61, 62, and 63 are disposed symmetrically with respect to the central axis C.

  Two opposing side surfaces of the third conductor 63 form two first joint surfaces 63 a, and these first joint surfaces 63 a are the first joint surface 61 a of the first conductor 61 and the first joint of the second conductor 62. The surfaces 62a face each other in parallel. Moreover, the other side surface orthogonal to the two side surfaces of the third conductor 63 forms a second bonding surface. The second joint surface is located in the same plane as the second joint surfaces of the first and second conductors 61 and 62.

  One joint surface 63a of the third conductor 63 is joined to the negative side (emitter and anode, respectively) of the IGBT 41a and the diode 51a constituting the upper arm, and the third conductor 63 is connected to the negative electrode side electrode of the IGBT 41a and the diode 51a. Electrically and mechanically connected. The other first joining surface 63a of the third conductor 63 is joined to the positive side (collector and cathode, respectively) of the IGBT 41b and the diode 51b constituting the lower arm, and the third conductor 63 is joined to the positive side of the IGBT 41b and the diode 51b. The electrode is electrically and mechanically connected. Thereby, the 3rd conductor 63 comprises the alternating current electrode conductor (electrode conductor).

  As shown in FIGS. 2 and 3, the IGBT 41 a joined to one first joint surface 63 a of the third conductor 63 is compared to the IGBT 41 b joined to the other first joint surface 63 a of the third conductor 63. Arranged at a position shifted in the direction along the central axis C of the third conductor, facing the diode 51b joined to the other first joint surface of the third conductor 63 without facing the IGBT 41b. ing. Similarly, the IGBT 41b joined to the other first joining surface 63a of the third conductor 63 is arranged to face the diode 51a joined to the third conductor 63. In other words, as can be clearly understood from FIG. 2, the IGBTs 41 a and 41 b joined to both sides of the third conductor 63 are provided at positions asymmetric with respect to the central axis C of the third conductor.

  Note that the bonding surfaces of the conductors described above and the IGBT and the diode can be bonded by solder or a conductive adhesive, or may be bonded via a thermal shock plate. The material of the first, second, and third conductors 61, 62, and 63 is preferably copper from the viewpoint of cooling, but may be a metal other than aluminum or a metal composite material such as Al—SiC.

  As shown in FIGS. 2 and 3, the heat radiating plate 67 is bonded to the second joining surfaces of the first conductor 61, the second conductor 62, and the third conductor 63 via the sheet-like insulator 66, and these conductors are connected to each other. I support it. The heat radiating plate 67 functioning as a heat radiating member is formed of, for example, a metal having high heat conductivity such as copper or aluminum, and radiates heat of the IGBT, the diode, and the first to third conductors to the outside. The sheet-like insulator 66 is formed of a material having a sufficiently low rigidity with respect to the first to third conductors, for example, an epoxy resin having adhesiveness filled with a ceramic filler such as boron nitride.

The upper surface of the heat radiating plate 67 joined to the first, second, and third conductors 61, 62, 63, that is, the joint surface is the first joint surface 61 a of the first conductor 61 and the first joint surface of the second conductor 62. 62a and the third conductor 63 extend in a direction intersecting the first joint surface 63a, for example, a direction orthogonal thereto. That is, the semiconductor elements of the IGBT and the diode are arranged so that the positive electrode side and the negative electrode side surface are not parallel to the bonding surface of the heat sink 67.
A heat conduction grease (not shown) is applied to the back surface of the heat radiating plate 67, and the heat radiating plate is joined to the cooler of the inverter device via the heat conduction grease and fixed by screws or the like.

  As shown in FIGS. 2 and 3, a positive electrode output terminal 71 is connected to one end of the first conductor 61 in the axial direction, and extends in one direction from the first conductor. A negative electrode output terminal 72 is connected to one end of the second conductor 62 in the axial direction, and extends from one end of the second conductor in the same direction as the positive electrode output terminal 71. An AC output terminal 73 is connected to the other axial end of the third conductor 63, that is, the other end located on the opposite side of the positive output terminal 71, and the direction opposite to the positive output terminal 71 from the other end of the third conductor. It extends to.

  A plurality of input / output terminals 76a and 76b such as gate terminals are connected to each of the IGBTs 41a and 41b. Of the input / output terminals that drive each IGBT, the emitter sense terminal is provided at a position other than the IGBT element, that is, at a position separated from the surface of the emitter electrode of the IGBT.

  In the present embodiment, the emitter sense terminal 78a corresponding to the IGBT 41a is formed integrally with the AC output terminal 73 and protrudes upward from the base end portion of the AC output terminal. The emitter sense terminal 78b corresponding to the IGBT 41b is formed integrally with the negative electrode output terminal 72 and protrudes upward from the base end portion of the negative electrode output terminal.

  The first to third conductors 61, 62, 63, and the first and second semiconductor elements are covered with a cover (not shown) formed of synthetic resin or the like. The cover is fixed to the heat sink 67, for example. The ends of the positive electrode output terminal 71, the negative electrode output terminal 72, and the AC output terminal 73 are provided so as to be exposed on the outer surface of the cover.

  With the above configuration, the power semiconductor module 16 for the U phase is obtained. The V-phase power semiconductor module 18 and the W-phase power semiconductor module 20 are configured in the same manner as the U-phase power semiconductor module 16 described above. That is, as shown in FIG. 1, the V-phase power semiconductor module 18 includes an IGBT 42a and a diode 52a that constitute the V-phase upper arm in the inverter circuit, an IGBT 42b and a diode 52b that constitute the V-phase lower arm, and a direct current A first conductor functioning as a positive electrode conductor, a second conductor functioning as a DC negative electrode conductor, a third conductor disposed between the first and second conductors and functioning as an AC electrode conductor, a positive electrode output terminal, a negative electrode output terminal, and an AC output A terminal, a sheet-like insulator, and a heat sink are provided.

  The power semiconductor module 20 for W phase includes an IGBT 43a and a diode 53a that constitute an upper arm of the W phase in the inverter circuit, an IGBT 43b and a diode 53b that constitute the lower arm of the W phase, a first conductor that functions as a DC positive conductor, Second conductor functioning as a DC negative conductor, third conductor disposed between the first and second conductors and functioning as an AC electrode conductor, positive output terminal, negative output terminal, AC output terminal, sheet-like insulator, heat sink It has.

  The three power semiconductor modules 16, 18, and 20 are arranged side by side on the same plane with the directions of the positive electrode output terminal, the negative electrode output terminal, and the AC output terminal matched. The positive output terminal and the negative output terminal of each of the power semiconductor modules 16, 18, and 20 are connected to the capacitor 24 and the DC power supply device or battery via a connection conductor (not shown). The AC output terminals of the power semiconductor modules 16, 18, and 20 are connected and connected to the motor 12 via the three-phase output connection conductor 26.

  According to the power semiconductor module of the inverter device configured as described above, the emitter sense terminal among the input / output terminals of the IGBT that is the switching element is provided at a position other than the IGBT element, for example, the base end of the output terminal Provided in the department. Therefore, a conductor is interposed between the emitter of the switching element and the emitter sense terminal, and the switching element has a structure having an inductance on the emitter side. Thereby, even when it is set as the structure which connects both surfaces of a switching element to a conductor, generation | occurrence | production of the electric current and voltage oscillation phenomenon in a switching element can be prevented.

  FIG. 4 shows current and voltage characteristics when the switching element is driven in the comparative example in which the emitter sense terminal is provided in the switching element. FIG. 5 shows current and voltage characteristics when the switching element is driven in the power semiconductor module according to the present embodiment. As shown in FIGS. 4 and 5, in the comparative example, the current and voltage vibrate when the switching element is driven, whereas in the power semiconductor module according to the present embodiment, the current and voltage are It can be seen that the voltage oscillation is greatly reduced.

  In this way, a power semiconductor module and an inverter device that can suppress a vibration of current and voltage and supply a stable output can be obtained.

  Further, according to the power semiconductor module having the above configuration, by disposing each semiconductor element between electrode conductors having a large heat capacity, heat generated from the semiconductor element can be efficiently radiated through the plurality of electrode conductors. As a result, the thermal resistance of the semiconductor element can be reduced by about 60% compared to the conventional power semiconductor module.

  In the power semiconductor module, the plurality of IGBTs that generate a large amount of heat compared to the diodes are provided at positions shifted from each other with respect to the direction of the central axis of the third conductor without facing each other. That is, the IGBTs disposed on both sides of the third conductor are disposed at positions that are asymmetric with respect to the central axis of the third conductor. Therefore, it is possible to suppress the accumulation of heat in the third conductor and improve the cooling efficiency. From the above, a power semiconductor module and a semiconductor power conversion device with improved cooling efficiency can be obtained.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  In each of the embodiments described above, the IGBT is used as the switching element. However, other types of transistors, thyristors, or the like may be used. In each embodiment, the number of mounting IGBTs and diodes can be increased or decreased as necessary. The semiconductor element can be appropriately changed depending on the purpose and application of an object (for example, an electric vehicle) to which the semiconductor power conversion device is applied, and an optimal power capacity or the like can be selected. Further, the power semiconductor module is not limited to the above-described two-arm configuration, and may have a multi-arm structure of three or more arms. The semiconductor power conversion device is not limited to an inverter device that converts DC power into three-phase AC power, but can also be applied to an inverter device that converts DC power into single-phase AC power.

FIG. 1 is an equivalent circuit diagram of an inverter device according to an embodiment of the present invention. FIG. 2 is a perspective view showing the power semiconductor module in the inverter device with its cover removed. FIG. 3 is a plan view showing the power semiconductor module. FIG. 4 is a diagram illustrating current and voltage characteristics of a switching element in a power semiconductor module according to a comparative example. FIG. 5 is a diagram showing current and voltage characteristics of a switching element in the power semiconductor module according to the present embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Inverter apparatus, 12 ... Motor, 16, 18, 20 ... Power semiconductor module,
22 ... Battery, 24 ... Capacitor, 32 ... Control unit, 34 ... Drive board,
41a, 41b, 42a, 42b, 43a, 43b ... IGBT,
51a, 51b, 52a, 52b, 53a, 53b ... diode,
61 ... 1st conductor, 62 ... 2nd conductor, 63 ... 3rd conductor, 67 ... Heat sink,
71: Positive DC output terminal, 72: Negative DC output terminal, 73: AC output terminal,
78a, 78b, 78c ... Emitter sense terminals

Claims (8)

A semiconductor element including a switching element and constituting one arm;
A positive electrode conductor bonded to the positive electrode side of the semiconductor element;
An electrode conductor bonded to the negative electrode side of the semiconductor element;
Input / output terminals provided in the switching element;
And an emitter sense terminal that is provided at a position other than the switching element and drives the switching element.   The power semiconductor module according to claim 1, further comprising: an output terminal extending from the positive electrode conductor; and an output terminal extending from the electrode conductor, wherein the emitter sense terminal is provided at the output terminal. A first semiconductor element including a first switching element and constituting one arm;
A second semiconductor element including a second switching element and constituting another arm;
A first conductor bonded to the positive electrode side of the first semiconductor element;
A second conductor joined to the negative electrode side of the second semiconductor element;
A third conductor disposed between the first conductor and the second conductor and joined to the negative electrode side of the first semiconductor element and the positive electrode side of the second semiconductor element;
A plurality of input / output terminals provided in the first switching element and the second switching element;
And an emitter sense terminal provided at a position other than the first and second switching elements and driving the first and second switching elements. A first output terminal extending from the first conductor; a second output terminal extending from the second conductor; and a third output terminal extending from the third conductor;
The power semiconductor module according to claim 3, wherein the emitter sense terminal is provided at the first, second, and third output terminals. The first conductor, the second conductor, and the third conductor are arranged in parallel to each other,
The first switching element is disposed between the first conductor and the third conductor, and the second semiconductor element is disposed between the second conductor and the third conductor. The power semiconductor module according to claim 3.   The power semiconductor module according to any one of claims 3 to 5, further comprising a heat dissipation member having a joint surface joined to the first conductor, the second conductor, and the third conductor.   The joint surface between the first conductor and the first semiconductor element, the joint surface between the second conductor and the second semiconductor element, and the joint surface between the third conductor and the first semiconductor element and the second semiconductor element are as follows: The power semiconductor module according to claim 6, wherein each of the power semiconductor modules extends so as to intersect with a joint surface of the heat radiating member. The power semiconductor module according to any one of claims 1 to 7,
A drive circuit for driving the power semiconductor module;
And a control circuit for controlling the power semiconductor module.

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