Semiconductor module

Abstract

Semiconductor module (11) with: an IGBT (14) and a MOSFET (15) connected in parallel to each other between a first terminal (11p) and a second terminal (11n), and provided on the same housing frame (16); wherein either the IGBT (14) or the MOSFET (15) is a first switching element (14) and the remaining one is a second switching element (15); and wherein, when the semiconductor module (11) is viewed from a thickness direction (X) of the semiconductor module (11), the second switching element (15) is arranged at a position separated from a first conduction path (Pa) from the first connection terminal (11p) via the first switching element (14) to the second connection terminal (11n) in the same housing frame (16), and the first switching element (14) is arranged at a position separated from a second conduction path (Pb) from the first connection terminal (11p) via the second switching element (15) to the second connection terminal (11n) in the same housing frame (16).

Description

BACKGROUND OF THE INVENTION Technical field of the invention

[0001] The present invention relates to a semiconductor module. STATE OF THE ART

[0002] Conventionally, a configuration in which an IGBT having excellent performance in a high current range is combined with a MOSFET having excellent performance in a low current range is known as a semiconductor module constituting an electric power converter.

[0003] For example, JP 5 863 599 B2 and JP 5 805 513 B2 each disclose a semiconductor module (power module) provided with an IGBT and a MOSFET connected in parallel to each other.

[0004] This semiconductor module is advantageous in that it has excellent properties of both an IGBT and a MOSFET.

[0005] When designing a semiconductor module equipped with both the IGBT and the MOSFET, there is a requirement that the occurrence of thermal influence (also called thermal damage) such that the two switching elements thermally affect each other is suppressed.

[0006] In response to this requirement, the semiconductor module disclosed in JP 5 863 599 B2 adopts a structure that does not forcibly cool the MOSFET with high thermal resistance, so that the IGBT is likely to receive thermal influence from the MOSFET when the temperature of the MOSFET becomes high.

[0007] In addition, the semiconductor module disclosed in JP 5 805 513 B2 is configured such that a current flows through the bus bar directly under the MOSFET when the IGBT is energized, and the MOSFET is likely to receive thermal influence from the bus bar in a high-temperature state.

[0008] Relevant prior art can be found, for example, in document US 2014 / 0 055 173 A1, which discloses a power module. Furthermore, document US 2014 / 0 070 269 A1 discloses a semiconductor device, document US 2013 / 0 155 745 A1 discloses a power semiconductor device, document JP 2012-5 009 A discloses a semiconductor device, and document JP 2009-59 887 A discloses a power converter. SUMMARY OF THE INVENTION

[0009] The present invention has been made in view of the problems described above and has an object to provide a semiconductor module in which a switching element is less likely to receive thermal influence.

[0010] An embodiment of a semiconductor module includes an IGBT and a MOSFET according to claim 1.

[0011] Another embodiment of a semiconductor module includes a plurality of semiconductor element pairs according to claim 6.

[0012] In the semiconductor module of the first aspect described above, the second switching element is less likely to be thermally influenced by heat generated in the conduction path of the first switching element when the first switching element is driven.

[0013] Likewise, the first switching element is less likely to be thermally affected by heat generated in the conduction path of the second switching element when the second switching element is driven.

[0014] This means that any influence caused by the thermal influence that the two switching elements may have on each other can be suppressed.

[0015] In the semiconductor module of the second embodiment described above, the second switching element is less likely to be thermally affected by heat generated in the conduction path because the second switching element is not arranged on the conduction path of the first switching element driven first.

[0016] As described above, it is possible to provide a semiconductor module in which the switching element is less likely to receive thermal influence according to each of the configurations described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In the accompanying drawings: Fig. 1 shows a schematic plan view of an electrical power converter according to a first embodiment; Fig. 2 shows a perspective view of the electrical power converter of Fig. 1; Fig. 3 is a side view of the semiconductor module of Fig. 1 in a thickness direction; Fig. 4 shows a line IV-IV of Fig. 3 recorded cross-sectional image; Fig. 5 shows an inverter circuit diagram of the electrical power converter from Fig. 1; Fig. 6 shows an equivalent circuit diagram of the semiconductor module from Fig. 5; Fig. 7 shows a modification of the equivalent circuit from Fig. 6; Fig. 8 shows a diagram for explaining a switching control; Fig. 9 is a diagram for explaining a loss of the semiconductor element; Fig. 10 is a side view showing a relationship between the semiconductor module of Fig. 5 and a flow of a coolant in a coolant channel of a cooling device; Fig. 11 shows a non-claimed modification of Fig. 10; Fig. 12 shows a further modification of Fig. 10; Fig. 13 is a side view of a semiconductor module in a thickness direction in an electric power converter according to a second embodiment; Fig. 14 is a line XIV-XIV from Fig. 13 recorded cross-sectional image; Fig. 15 is an equivalent circuit diagram of the semiconductor module from Fig. 13; Fig. 16 shows a modification of the equivalent circuit from Fig. 15; Fig. 17 is a side view showing a relationship between the semiconductor module of Fig. 13 and a flow of a coolant in a coolant channel of a cooling device; and Fig. 18 shows an unclaimed modification of Fig. 17. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] Hereinafter, an embodiment relating to an electric power converter will be described with reference to the drawings.

[0019] It should be noted that in the drawings of the present specification, unless otherwise specified, a first direction, which is a stacking direction of semiconductor modules and cooling lines, is indicated by an arrow X, a second direction, which is a longitudinal direction of the cooling line, is indicated by an arrow Y, and a third direction, which is orthogonal to both the first direction and the second direction, is indicated by an arrow Z.

[0020] An electric power converter of the present embodiment is a device that converts electric power.

[0021] This electrical power converter is installed, for example, in an electric vehicle, a hybrid vehicle, or the like, and is used as an inverter to convert DC power into AC power required to drive a drive motor, and is also used as a converter to convert DC power into boosted or stepped DC power. [First embodiment]

[0022] As in Fig. 1 and Fig. 2, an electric power converter 1 of the first embodiment includes a plurality of components including a laminated semiconductor unit 10 and a control board 30.

[0023] These components are housed in an area divided by a housing 1a.

[0024] The housing 1a is an automotive component requiring lightweight construction and high dimensional accuracy and is manufactured by an aluminum die-casting process using aluminum.

[0025] The laminated semiconductor unit 10 includes a plurality of semiconductor modules 11 and a cooling device 20 for cooling these semiconductor modules 11.

[0026] The cooling device 20 includes an inlet pipe (inflow manifold) 21 extending in the first direction X and a drain pipe (outflow manifold) 22 extending in the first direction X, and a plurality of cooling pipes 23 each extending in the second direction Y, arranged in a predetermined range in the first direction X.

[0027] In the laminated semiconductor unit 10, the plurality of semiconductor modules 11 and the plurality of cooling lines 23 are alternately laminated in the first direction X.

[0028] In this case, each of the semiconductor modules 11 has two outer surfaces 11a, 11a extending parallel to each other, and each of the cooling lines 23 is arranged to be in contact with each of the two outer surfaces 11a, 11a of the semiconductor modules 11.

[0029] This means that each semiconductor module 11 is inserted from both sides between two cooling lines 23, 23.

[0030] It should be noted that this laminated semiconductor unit 10 may also be referred to as an electrical power converter or a semiconductor module.

[0031] Each of a plurality of control terminals (a plurality of control terminals 14a, 15a as described later) of the semiconductor module 11 is connected to the control board 30.

[0032] A control current for controlling a switching operation of a semiconductor element of the semiconductor module 11 is input from the control board 30 into the semiconductor module 11 through these control terminals.

[0033] In the cooling device 20, corresponding inflow portions of the plurality of cooling lines 23 are connected to the inlet line 21 and corresponding outflow portions of the plurality of cooling lines 23 are connected to the outflow line 22.

[0034] Furthermore, each of the cooling lines 23 has a coolant channel 24 in the line.

[0035] Therefore, a coolant flowing into the inflow portions of the cooling pipes 23 from the inlet pipe 21, flowing through the coolant channel 24 in the cooling pipes 23, cools the semiconductor module 11 in contact with the cooling pipes 23, and is then discharged from the cooling pipes 23 into the drain pipe 22.

[0036] The cooling device 20 is composed of a material with excellent thermal conductivity such as aluminum.

[0037] Optionally, for example, ethylene glycol-based antifreeze mixed with water, natural coolants such as water or ammonia, fluorocarbon coolants such as FLUORINERT™, HCFC123, fluorocarbon coolants such as HFC134a, alcohol-based coolants such as methanol or alcohol, ketone-based coolants such as acetone can be used as a coolant flowing into the coolant channel 24 of the cooling line 23.

[0038] As in Fig. 3 and Fig. 4, the semiconductor module 11 is provided with an IGBT (insulated gate bipolar transistor) 14, a MOSFET (metal oxide semiconductor field effect transistor) 15, and a housing frame 16.

[0039] This semiconductor module 11 is provided with a semiconductor element pair composed of the IGBT 14 and the MOSFET 15 and is referred to as a “1 in 1 module”.

[0040] Both the IGBT 14 and the MOSFET 15 are switching elements.

[0041] In the present embodiment, the IGBT 14 is an insulated gate bipolar transistor formed of a Si-based (silicon) material, and the MOSFET 15 is a field effect transistor formed of a wide band gap semiconductor.

[0042] The IGBT 14 has excellent high current performance and is cost-effective compared to the MOSFET 15.

[0043] The MOSFET 15 has excellent low current and high speed switching characteristics.

[0044] Note that a wide band gap semiconductor element composed of SiC-based (silicon carbide) material, GaN-based (gallium nitride) material, or the like is preferably used as the MOSFET 15 formed of a wide band gap semiconductor.

[0045] As in Fig. As shown in Fig. 4, the semiconductor module 11 is formed from a molding resin 11b.

[0046] One of the element surfaces of the IGBT 14 is joined to the case frame 16 via a solder layer 11c, and another of the element surfaces is joined to a terminal 18 joined to another case frame 17 via another solder layer 11c.

[0047] One of the element surfaces of the MOSFET 15 is joined to the package frame 16 via the solder layer 11c, and another of the element surfaces is joined to another terminal joined to the package frame 17 via the other solder layer 11c.

[0048] The housing frames 16 and 17 simultaneously support and fix the IGBT 14 and the MOSFET 15, and represent an input / output terminal for input from the outside and output to the outside.

[0049] These housing frames 16, 17 are composed of a thin plate of metallic material such as a copper alloy material, an iron alloy material, or other metallic material having excellent mechanical strength, electrical conductivity, thermal conductivity, corrosion resistance and the like.

[0050] The semiconductor module 11 has, as a power terminal, a P terminal 11p, which is a first terminal, and an N terminal 11n, which is a second terminal, which extend parallel to each other from the housing frames 16 and 17.

[0051] The P terminal 11p extends from the housing frame 16 along the third direction Z, and the N terminal 11n extends from the housing frame 17 along the third direction Z.

[0052] DC voltage is applied to the semiconductor module 11 via the P terminal 11p and the N terminal 11n.

[0053] In the semiconductor module 11 of the present embodiment, the IGBT 14 and the MOSFET 15 are provided on the same package frame 16.

[0054] Alternatively, it can be said that the IGBT 14 and the MOSFET 15 are provided on the same package frame 17.

[0055] In the semiconductor module 11, the control terminals 14a of the IGBT 14 and the control terminals 15a of the MOSFET 15 are each connected to the control board 30.

[0056] The IGBT 14 and the MOSFET 15 of the semiconductor module 11 are arranged side by side in a direction (second direction Y) crossing with an extending direction of the P- terminal 11p and the N- terminal 11n (the third direction Z).

[0057] Further, either the IGBT 14 or the MOSFET 15 is a first switching element and the remaining one is a second switching element, and when the semiconductor module 11 is viewed from a thickness direction (first direction X) of the element, it is formed such that the second switching element is arranged at a position separated from a conduction path of the first switching element in the same package frame 16.

[0058] Specifically, the MOSFET 15 used as the second switching element is arranged at a position separated from the conduction path Pa of the IGBT 14 used as the first switching element (a position without overlap) when the semiconductor module 11 is viewed from the thickness direction of the element.

[0059] This means that the MOSFET 15 is not arranged on the conduction path Pa of the IGBT 14.

[0060] On the other hand, the IGBT 14 is arranged at a position separated from the conduction path Pb of the MOSFET 15 (a position without overlap) when the semiconductor module 11 is viewed from the thickness direction of the element.

[0061] This means that the IGBT 14 is not arranged on the conduction path Pb of the MOSFET 15.

[0062] Here, the conduction path Pa is a conduction path formed between the P terminal 11p and the N terminal 11n via the IGBT 14 and is a region in which a current flows mainly to drive the IGBT 14.

[0063] Furthermore, the conduction path Pb is a conduction path formed between the P terminal 11p and the N terminal 11n via the MOSFET 15 and is a region in which a current flows mainly to drive the MOSFET 15.

[0064] The semiconductor module 11 is configured such that the length of the conduction path Pa of the IGBT 14 is shorter than the length of the conduction path Pb of the MOSFET 15.

[0065] In this case, an inductance of the shorter conduction path Pa is smaller than an inductance of the other conduction path Pb.

[0066] As in Fig. 5 shows an inverter circuit 40 of the electric power converter 1 by using a plurality (eight in Fig. 5) of semiconductor modules 11.

[0067] The eight semiconductor modules 11 are divided into two modules 11C, 11C forming a voltage boosting circuit for increasing the voltage of the power supply B and six modules forming a conversion circuit for converting increased DC power into AC power.

[0068] The six modules of the conversion circuit are further divided into three upper arm modules 11H connected to a high-potential side line Lp of the power supply B and three lower arm modules 11L connected to a low-potential side line Ln of the power supply B.

[0069] With regard to an equivalent circuit from Fig. 6, the IGBT 14 and the MOSFET 15 are connected in parallel to each other in the semiconductor module 11.

[0070] Specifically, a collector of the IGBT 14 and a drain of the MOSFET 15 are connected, and an emitter of the IGBT 14 and an inflow of the MOSFET 15 are connected.

[0071] A gate electrode of the IGBT 14 and a gate electrode of the MOSFET 15 are connected to the control board 30.

[0072] A three-phase AC motor M for driving the vehicle is driven by an AC power obtained by the inverter circuit 40.

[0073] The equivalent circuit can adopt a structure composed of the IGBT 14 and a FWD (free wheeling diode) for an equal reverse current, or separate elements (see a diagram in Fig. 7 shown FWD 14D) or a body diode of the MOSFET 15 or a synchronous rectification can also be adopted.

[0074] As in Fig. 8, the control board 30 in the semiconductor module 11 of the present embodiment controls such that the IGBT 14 is driven (turned on) before the MOSFET 15 and the IGBT 14 is turned off after the MOSFET 15 is turned off.

[0075] This means that the IGBT 14 is always switched on when the MOS-FET 15 switches.

[0076] In this case, the IGBT 14 becomes an element that mainly performs the switching operation (hereinafter referred to as the main element), and the MOSFET 15 becomes an element that supports or assists the IGBT 14 (hereinafter referred to as the sub-element).

[0077] According to such a Fig. 9, the MOSFET 15 can be switched to a state in which the IGBT 14 is turned on and the voltage applied to the MOSFET 15 (ON voltage) is reduced.

[0078] Therefore, the switching loss La does not occur in the MOSFET 15, although the switching loss La occurs in the IGBT 14.

[0079] As a result, the switching loss La is borne by the IGBT 14 and the conduction loss Lb is shared by the IGBT 14 and the MOSFET 15.

[0080] In this case, the load of the MOSFET 15 can be reduced and the element size of the MOSFET 15 can be reduced accordingly.

[0081] Further, since it is known that in the low current time, which is an operating point where the influence on fuel consumption (also called electricity cost) is large and charge easily flows to the MOSFET 15, the resistance of the MOSFET 15 is lower than the resistance of the IGBT 14, it is effective to improve the fuel consumption economy.

[0082] Here, a switching loss La is a loss (product of voltage and current) at the switching time Δt of the switching element.

[0083] On the other hand, a conduction loss Lb is a loss (product of voltage and current) in the “ON period” excluding the switching time Δt of the switching element.

[0084] Furthermore, as described above, since the charge path Pa of the main element IGBT 14 is shorter than the charge path Pb of the sub-element MOSFET 15, the switching loss by the IGBT 14 can be kept low and the element size of the IGBT 14 can be reduced, and therefore the inductance becomes lower in the present embodiment.

[0085] Incidentally, in the above-mentioned control, if the switching speed is increased when the IGBT 14 is switched from the OFF state to the ON state (turning on), a time change rate di / dt of a main current i increases and a large induced current is likely to occur.

[0086] Therefore, the semiconductor module 11 of the present embodiment is preferably configured so that at this time the induced current flows in a direction to turn off the MOSFET 15.

[0087] According to the present embodiment, the MOSFET 15 is not turned on even if a high induced current flows.

[0088] Therefore, it is possible to suppress an increase in the switching loss La of the MOSFET 15 by simultaneously turning on the MOSFET 15 with the IGBT 14.

[0089] In addition, when the IGBT 14 is switched from the ON state to the OFF state, an induction current occurs at the control terminal 15a of the MOSFET in the same manner as when the IGBT 14 is turned on.

[0090] The induced current flows in a direction opposite to that when the IGBT 14 is turned on (at the time of high-speed switching).

[0091] This means that the induced current flows in the direction to turn on the MOSFET 15.

[0092] Therefore, the semiconductor module 11 of the present embodiment is preferably configured to slow down the switching speed of the IGBT 14 when the IGBT 14 is turned off.

[0093] According to the present arrangement, the induced current occurring when the IGBT 14 is turned off can be reduced and the turning on of the MOSFET 15 can be suppressed.

[0094] As in Fig. 10, the cooling lines 23 of the cooling device 20 are indirectly in contact via insulators (not shown) with the housing frames 16, 17 forming the outer surfaces 11a, 11a of the semiconductor module 11.

[0095] The outer surfaces 11a, 11a of the semiconductor module 11 form heat radiation surfaces and surfaces of the cooling lines 23 form heat absorption surfaces.

[0096] In this case, the coolant channel 24 of the cooling lines 23 is arranged such that it extends opposite to the housing frames 16, 17.

[0097] Then, the semiconductor module 11 is configured such that the first-driven IGBT 14 is arranged on an upstream side of the MOSFET 15 with respect to a flow F of the coolant in the coolant channel 24 of the cooling device 20.

[0098] In other words, the semiconductor module 11 is configured such that the first-driven IGBT 14 is not located on the downstream side of the MOSFET 15 with respect to the flow F of the coolant in the coolant channel 24 of the cooling device 20.

[0099] The present embodiment is achieved by appropriately adjusting the arrangement relationship of the IGBT 14 and the MOSFET 15 in the semiconductor module 11, the arrangement of the coolant channel 24 in the cooling device 20, and the like.

[0100] According to the present embodiment, the cooling of the IGBT 14 can be improved because the IGBT 14 is cooled before the MOSFET 15 and the IGBT 14 is not cooled after the MOSFET 15.

[0101] Next, functions and effects of the electric power converter 1 of the first embodiment will be described.

[0102] According to the electric power converter 1, the MOSFET 15 in the conduction path Pa of the IGBT 14 is less likely to receive thermal influence generated when the IGBT 14 is driven, since one of the switching elements is not arranged on the conduction path of the other switching element of the semiconductor module 11.

[0103] Likewise, the IGBT 14 in the conduction path Pb of the MOSFET 15 is less likely to receive thermal influence generated when the MOSFET 15 is driven.

[0104] This means that it is possible to suppress the mutual thermal influence between the two switching elements, the IGBT 14 and the MOSFET 15.

[0105] In addition, by suppressing this thermal influence, the performance of both the IGBT 14 and the MOSFET 15 is increased and the element size of each switching element can be reduced accordingly.

[0106] According to the electric power converter 1 described above, since the first-driven IGBT 14 is cooled before the MOSFET 15, the performance of the IGBT 14 can be kept high and the element size of the IGBT 14 can be reduced accordingly.

[0107] In connection with the as in Fig. 10 shown arrangement of the switching elements (IGBT 14, MOSFET 15) it is possible, as in Fig. 11 and Fig. 12 shown arrangements of the switching elements.

[0108] The Fig. The semiconductor module 11 (not claimed) shown in Fig. 11 is arranged such that the IGBT 14 is arranged at the same position as the MOSFET 15 with respect to the flow F of the coolant in the coolant channel 24 of the cooling device 20.

[0109] Even in this case, analogous to the case of Fig. 10, the first-driven IGBT 14 is not arranged on a downstream side of the MOSFET 15 with respect to the flow F of the coolant in the coolant channel 24 of the cooling device 20.

[0110] Furthermore, in the Fig. 12, the cooling line 23 of the cooling device is arranged such that four different coolant flows Fa, Fb, Fc, and Fd are formed in the coolant channel 24.

[0111] In the coolant channel 24, the flow Fa of the coolant flowing into the cooling line 23 branches into two flows Fb and Fc and then flows parallel to the MOSFET 15 and the IGBT 14, and then becomes the flow Fd of the merged coolant and flows out of the cooling line 23.

[0112] Such flows are formed by a plurality of radiation fins 26 provided in the coolant channel 24 of the cooling line 23.

[0113] Each of the plurality of radiating fins 26 is configured to extend in parallel in the third direction Z, and has an effect of improving the cooling performance by increasing contact areas with the coolant to effectively increase the heat exchange efficiency.

[0114] In this case as well as in the case from Fig. 10, the first-driven IGBT 14 is not located on the downstream side of the MOSFET 15 with respect to the coolant flows Fa, Fb, Fc, Fd in the coolant channel 24 of the cooling device 20.

[0115] Therefore, the cooling of the IGBT 14 as in the case of the Fig. 11 and Fig. 12, since the IGBT 14, which is to be driven earlier, is not cooled after the MOSFET 15. [Second embodiment]

[0116] It should be noted that components identical or similar to those in the first embodiment are provided with the same reference numerals in the second embodiment, and repeated structures and features will not be described to avoid redundant explanations.

[0117] An electric power converter 2 of the second embodiment differs from the electric power converter 1 of the first embodiment in the number of semiconductor element pairs composed of an IGBT 14 and a MOSFET 15.

[0118] That is, a semiconductor module 111 of the electrical power converter 2 is provided with two semiconductor element pairs composed of the IGBT 14 and the MOSFET 15.

[0119] This semiconductor module 111 is provided with two pairs of semiconductor elements in which the IGBT 14 and the MOSFET 15 are connected in parallel to each other, and these two pairs of semiconductor elements are connected in series and arranged between a high-potential side line Lp and a low-potential side line Ln of a power supply B.

[0120] This semiconductor module 111 is called a “2 in 1 module”.

[0121] This semiconductor module 111 has a configuration in which a single upper arm module 11H and a single lower arm module 11L are Fig. 5 are combined.

[0122] It should be noted that a semiconductor module with three or more pairs of semiconductor elements can also be adopted if necessary.

[0123] Other configurations are the same as those in the first embodiment.

[0124] As in Fig. 13 and Fig. As shown in Figure 15, the semiconductor module 111 is provided with a P-terminal 11p, an N-terminal 11n and an O-terminal 11o as power terminals.

[0125] The DC voltage is applied to the semiconductor module 111 through the P terminal 11p and the N terminal 11n, and the AC power is output from the semiconductor module 111 through the O terminal 11o.

[0126] One in Fig. The equivalent circuit shown in Figure 15 can adopt a structure composed of the IGBT 14 and a FWD (free wheeling diode) for equal reverse current, or separate elements (see an example shown in Fig. 16 shown FWD 14D), or a body diode of the MOSFET 15, or a synchronous rectification can also be adopted.

[0127] As in Fig. 14, the semiconductor module 111 is molded with the same molding resin 11b as the semiconductor module 11.

[0128] One of the element surfaces of the left-side IGBT 14 in Fig. 14 is joined to the housing frame 17 via a solder layer 11c.

[0129] In addition, another of the element surfaces of the IGBT 14 is joined to a terminal 18 joined to a case frame 16 via another solder layer 11c.

[0130] One of the element surfaces of the right-side IGBT 14 in Fig. 14 is joined to another housing frame 16 via the solder layer 11c.

[0131] In addition, another of the element surfaces of the IGBT 14 is joined to another terminal 18 joined to another housing frame 17 via another solder layer 11c.

[0132] The housing frames 17 consisting of two frames are integrated via another solder layer 11c.

[0133] One of the element surfaces of the left-side MOSFET 15 in Fig. 14 is joined to the housing frame 17 via a solder layer 11c.

[0134] In addition, another of the element surfaces of the IGBT 15 is joined to a terminal 19 joined to the housing frame 16 via another solder layer 11c.

[0135] One of the element surfaces of the right-side MOSFET 15 in Fig. 14 is joined to another housing frame 16 via another solder layer 11c.

[0136] In addition, another of the element surfaces of the MOSFET 15 is joined to another terminal 19 joined to the package frame 17 via another solder layer 11c.

[0137] In the semiconductor module 111, the P-terminal 11p extends from one of the package frames 16 along the third direction Z, and the N-terminal 11n extends from another of the package frames 16 along the third direction Z.

[0138] In the semiconductor module 111 of the present embodiment, the IGBT 14 and the MOSFET 15 of one semiconductor element pair are arranged on the same package frame 16, and the IGBT 14 and the MOSFET 15 of the other semiconductor element pair are arranged on the same package frame 17.

[0139] The semiconductor module 111 is controlled by the control board 30 such that the two IGBTs 14, 14 included in the two semiconductor element pairs are controlled before the two MOSFETs 15, 15.

[0140] The semiconductor module 111 is arranged side by side in the direction (second direction Y) in which the two IGBTs 14, 14 and the two MOSFETs 15, 15 intersect with the extending direction of the P terminal 11p, the N terminal 11n and the O terminal 11o (third direction Z).

[0141] In particular, the MOSFET 15, the IGBT 14, the IGBT 14, and the MOSFET 15 in Fig. 13 arranged in order from the left.

[0142] When viewing the module from the thickness direction of the element (the first direction X) with respect to a semiconductor element arranged between the high-potential side line Lp and the AC output line Lo among the two semiconductor element pairs, the semiconductor module 111 is configured such that the MOSFET 15 is arranged at a position (a non-overlapping position) that is not in the conductive path Pc formed between the high-potential side line Lp and the AC output line Lo via the IGBT 14.

[0143] This conduction path Pc is a conduction path formed between the P terminal 11p and the O terminal 11o via the IGBT 14.

[0144] In the present embodiment, the MOSFET 15 is arranged at a position separated from the conduction path Pc of the first-driven IGBT 14.

[0145] This means that the MOSFET 15 is not arranged on the conduction path Pc of the IGBT 14.

[0146] Also, when viewing the module from the thickness direction of the element (the first direction X), with respect to a semiconductor element arranged between the low-potential side wiring Ln and the AC output wiring Lo among the two semiconductor element pairs, the semiconductor module 111 is configured such that the MOSFET 15 is arranged at a position (a non-overlapping position) that is not in the conduction path Pd formed between the high-potential side wiring Lp and the AC output wiring Lo via the IGBT 14.

[0147] This conduction path Pd is a conduction path formed between the N terminal 11n and the O terminal 11o via the IGBT 14.

[0148] In the present embodiment, the MOSFET 15 is arranged at a position separated from the conduction path Pd of the first-driven IGBT 14.

[0149] This means that the MOSFET 15 is not arranged on the conduction path Pd of the IGBT 14.

[0150] In addition, the semiconductor module 111 is configured such that the length of the conduction paths of the two IGBTs 14, 14 driven first (conduction paths formed between the high-potential side line Lp and the low-potential side line Ln, which successively cross the two IGBTs 14, 14) is shorter than the conduction paths of the two MOSFETs 15, 15 (conduction paths formed between the high-potential side line Lp and the low-potential side line Ln, which successively cross the two MOSFETs 15, 15).

[0151] In this case, the inductance of the conduction paths with a relatively short length is smaller than the inductance of the conduction paths with a relatively long length.

[0152] As in Fig. 17, the semiconductor module 111 is configured such that, in the same housing frame 16 or 17, the IGBT 14 driven first in both semiconductor element pairs is not arranged on the downstream side of the MOSFET 15 with respect to the flow of the coolant F in the coolant channel 24 of the cooling device 20.

[0153] In particular, the cooling line 23 of the cooling device 20 is configured such that four different coolant flows Fa, Fb, Fc, and Fd are formed in the coolant channel 24.

[0154] In the coolant channel 24, the flow Fa of the coolant flowing into the cooling line 23 branches into two flows Fb and Fc and then flows parallel to the two pairs of semiconductor elements and then becomes the flow Fd of the combined coolant and flows out of the cooling line 23.

[0155] Such flows are achieved by providing a plurality of radiating fins 26 similar to the radiating fins 26 described above (see Fig. 12) in the coolant channel 24 of the cooling line 23.

[0156] During this time, the IGBT 14 and the MOSFET 15 of a semiconductor element pair are cooled at the same time by the flow Fb of the coolant.

[0157] Furthermore, the IGBT 14 and the MOSFET 15 of the other semiconductor element pair are cooled at the same time by the flow Fb of the coolant.

[0158] Therefore, the first-driven IGBT 14 is not cooled after the MOSFET 15 and the cooling of the IGBT 14 can be improved.

[0159] Next, functions and effects of the electric power converter 2 of the second embodiment will be described.

[0160] According to the electric power converter 2, the influence of heat generated in the conduction path Pc is hardly received by the MOSFET 15 because the MOSFET 15 is not arranged on the conduction path Pc of the first-driven IGBT 14 in the semiconductor module 111.

[0161] Likewise, the influence of heat generated in the conduction path Pc is hardly received by the MOSFET 15 because the MOSFET 15 is not arranged on the conduction path Pd of the first-driven IGBT 14.

[0162] Furthermore, since the conduction path formed between the high-potential side line Lp and the low-potential side line Ln, which sequentially passes through the two IGBTs 14, 14 which are main elements, is shorter and the inductance is smaller compared to the conduction path formed between the high-potential side line Lp and the low-potential side line Ln, which sequentially passes through the two MOSFETs 15, 15 which are sub-elements, the switching loss by the IGBT 14 can be kept low and the element size of the IGBT 14 can be made small.

[0163] It should be noted that a configuration in which two MOSFETs 15, 15 included in the two semiconductor element pairs are driven before the two IGBTs 14, 14 can be adopted if necessary.

[0164] In this case, it is preferable that the IGBT 14 is arranged at the position different from the conduction path of the first-driven MOSFET 15 (wherein the conduction path is formed between the P terminal 11p and the O terminal 11o, or the conduction path is formed between the N terminal 11n and the O terminal 11o).

[0165] This makes it less likely that the IGBT 14 will be thermally affected by heat generated in the conduction path of the MOSFET 15.

[0166] In this case, it is further preferable that the length of the conduction paths of the two first-driven MOSFETs 15, 15 (wherein the conduction paths formed between the high-potential side line Lp and the low-potential side line Ln pass sequentially through the two MOSFETs 15, 15) is set shorter than the length of the conduction path of the two IGBTs 14, 14 (wherein the conduction paths formed between the high-potential side line Lp and the low-potential side line Ln pass sequentially through the two IGBTs 14, 14).

[0167] This allows the switching loss through the MOSFET 15 to be kept low and the element size of the MOSFET 15 to be reduced.

[0168] In addition, the same functions and effects as those of the first embodiment can be achieved.

[0169] Furthermore, it is in connection with the Fig. 17 shown arrangement of the switching elements (IGBT 14, MOSFET 15) is possible, which as in Fig. 18. The arrangement of the switching elements shown must be adopted.

[0170] The Fig. The semiconductor module 111 (not claimed) shown in Figure 18 is configured such that, in the same housing frame 16, the MOSFET 15 is arranged at the same position as the IGBT 14 with respect to the flow F of the coolant in the coolant channel 24 of the cooling device 20, and that, in the same housing frame 17, the MOSFET 15 is arranged at the same position as the IGBT 14 with respect to the flow F of the coolant in the coolant channel 24 of the cooling device.

[0171] Even in this case, as in the case of Fig. 17, the first-driven IGBT 14 is not arranged on a downstream side of the MOSFET 15 with respect to the flow F of the coolant in the coolant channel 24 of the cooling device 20 in the same housing frame 16 or 17.

[0172] Therefore, in the case of Fig. 18, the first-activated IGBT 14 is not cooled after the MOSFET 15, and the cooling of the IGBT 14 can be improved.

[0173] For example, it is also possible to implement any of the following embodiments to which the above embodiment is applied.

[0174] In the above embodiment, the case where the IGBT 14 and the MOSFET 15 of the semiconductor module 11 are arranged side by side in the direction intersecting the extending direction of the P terminal 11p and the N terminal 11n is illustrated.

[0175] However, the arrangement relationship between the IGBT 14 and the MOSFET 15 can be appropriately changed as long as one switching element can be arranged at a position different from the conduction path of the other switching element.

[0176] In the above embodiment, the case has been illustrated in which the first-controlled switching element is arranged not to be arranged on the downstream side of another switching element with respect to the flow of the coolant in the coolant channel 24 of the cooling device 20.

[0177] However, the arrangement relationship of the two switching elements with respect to the flow of the coolant in the coolant passage 24 is not limited thereto and may be changed if necessary.

[0178] The cooling device 20 is described in which the cooling lines 23 are arranged to be in contact with each of the two outer surfaces 11a, 11a of the semiconductor module 11 in the above embodiment.

[0179] However, instead of this cooling device 20, a cooling device arranged so that a cooling surface thereof is only adjacent to an outer surface 11a of the semiconductor module 11 may be adopted.

[0180] The case where the length of the conduction path Pa of the IGBT 14 in the semiconductor module 11 is shorter than the length of the conduction path Pb of the MOSFET 15 has been illustrated in the above embodiment.

[0181] However, if necessary, it is also possible to adopt a configuration in which the lengths of the conduction path Pa and the conduction path Pb are the same, or a configuration in which the length of the conduction path Pa is longer than the length of the conduction path Pb.

[0182] Furthermore, it is also possible to adopt a configuration in the semiconductor module 111 in which the length L1 of the conductive path formed between the high-potential side line Lp and the low-potential side line Ln via the two IGBTs 14, 14 and the length L2 of the conductive path formed between the high-potential side line Lp and the low-potential side line Ln via the two MOSFETs 15, 15 are the same, or a configuration in which the length L1 exceeds the length L2 if necessary.

[0183] The case of using the IGBT 14 composed of a Si-based material and the MOSFET 15 composed of a SiC-based material is illustrated in the above embodiment.

[0184] However, it is also possible to use an IGBT 14 composed of a material other than Si-based material and a MOSFET 15 composed of a material other than SiC-based material if necessary.

[0185] A semiconductor module 11 of an electric power converter 1 includes an IGBT 14 and a MOSFET 15 connected in parallel to each other and provided on the same package frame 16, wherein either the IGBT 14 or the MOSFET 15 is a first switching element and the remaining one is a second switching element, and the conduction path of the second switching element is arranged at a position separated from a conduction path of the first switching element in the same package frame 16.

Claims

[1] Semiconductor module (11) with: an IGBT (14) and a MOSFET (15) connected in parallel to each other between a first terminal (11p) and a second terminal (11n), and provided on the same housing frame (16); wherein either the IGBT (14) or the MOSFET (15) is a first switching element (14) and the remaining one is a second switching element (15); and wherein, when the semiconductor module (11) is viewed from a thickness direction (X) of the semiconductor module (11), the second switching element (15) is arranged at a position separated from a first conduction path (Pa) from the first connection terminal (11p) via the first switching element (14) to the second connection terminal (11n) in the same housing frame (16), and the first switching element (14) is arranged at a position separated from a second conduction path (Pb) from the first connection terminal (11p) via the second switching element (15) to the second connection terminal (11n) in the same housing frame (16). [2] Semiconductor module (11) according to claim 1, wherein the first terminal (11p) and the second terminal (11n) extend parallel to each other from the housing frame (16); and the IGBT (14) and the MOSFET (15) are arranged side by side in a direction (Y) intersecting with an extension direction (Z) of the first terminal (11p) and the second terminal (11n). [3] Semiconductor module (11) according to claim 1 or 2, wherein the first switching element (14) is activated before the second switching element (15); and the length of a conduction path (Pa) formed between the first connection terminal (11p) and the second connection terminal (11n) via the first switching element (14) is shorter than the length of a conduction path (Pb) formed between the first connection terminal (11p) and the second connection terminal (11n) via the second switching element (15). [4] Semiconductor module (11) according to claim 3, wherein a cooling device (20) having a coolant channel (24) extending toward the housing frame (16) is attached to the semiconductor module (11); and the first switching element (14) which is driven first is adapted not to be arranged on a downstream side of the second switching element (15) with respect to a flow of a coolant in the coolant channel (24) of the cooling device (20). [5] The semiconductor module (11) according to claim 4, wherein the semiconductor module (11) is configured such that the first switching element (14) which is driven first is arranged on an upstream side of the second switching element (15) with respect to the flow of the coolant in the coolant channel (24) of the cooling device (20). [6] Semiconductor module (111) with: a plurality of semiconductor element pairs whose IGBTs (14) and MOSFETs (15) are connected in parallel to each other, wherein the semiconductor element pairs are connected in series between a terminal of a high-potential side line (Lp) and a terminal of a low-potential side line (Ln) of a power supply (B) and are provided on the same housing frame (16); wherein either a plurality of IGBTs (14) or a plurality of MOSFETs (15) included in the plurality of semiconductor element pairs is a plurality of first switching elements (14), and the remaining one is a plurality of second switching elements (15); the plurality of first switching elements (14) are controlled before the plurality of second switching elements (15); in a semiconductor element pair arranged between the terminal of the high-potential side line (Lp) and a terminal of an AC output line (Lo) among the plurality of semiconductor element pairs, the second switching element (15) is arranged at a position separated from a first conduction path (Pc) formed between the terminal of the high-potential side line (Lp) and the terminal of the AC output line (Lo) via the first switching element (14) when the semiconductor module (111) is viewed from a thickness direction (X) of the semiconductor module (111); in a semiconductor element pair arranged between the terminal of the low-potential side line (Ln) and the terminal of the AC output line (Lo) among the plurality of semiconductor element pairs, the second switching element (15) is arranged at a position separated from a second conduction path (Pd) formed between the terminal of the low-potential side line (Ln) and the terminal of the AC output line (Lo) via the first switching element (14) when the semiconductor module (111) is viewed from a thickness direction (X) of the semiconductor module (111), and in a direction that intersects with an extension direction of the terminal of the high-potential side line (Lp), the terminal of the AC output line (Lo), and the terminal of the low-potential side line (Ln), the second switching element (15) of the semiconductor element pair arranged between the terminal of the high-potential side line (Lp) and the terminal of the AC output line (Lo) among the plurality of semiconductor element pairs, the first switching element (14) of the semiconductor element pair arranged between the terminal of the high-potential side line (Lp) and the terminal of the AC output line (Lo) among the plurality of semiconductor element pairs, the first switching element (14) of the semiconductor element pair arranged between the terminal of the low-potential side line (Ln) and the terminal of the AC output line (Lo) among the plurality of semiconductor element pairs,and the second switching element (15) of the semiconductor element pair arranged between the terminal of the low-potential side line (Ln) and the terminal of the AC output line (Lo) among the plurality of semiconductor element pairs are arranged in this order., [7] The semiconductor module (111) according to claim 6, wherein a length of a conductive path formed between the high-potential side wiring (Lp) and the low-potential side wiring (Ln) sequentially passing through the plurality of first switching elements (14) is set shorter than a length of a conductive path formed between the high-potential side wiring (Lp) and the low-potential side wiring (Ln) sequentially passing through the plurality of second switching elements (15). [8] Semiconductor module (111) according to claim 6 or 7, wherein a cooling device (20) having a coolant channel (24) extending opposite the housing frame (16) is attached to the semiconductor module (111); and the first switching element (14) which is driven first in each of the plurality of semiconductor element pairs is arranged so that it is not arranged on a downstream side of the second switching element (15) with respect to a flow of a coolant in the coolant channel (24) of the cooling device (20). [9] The semiconductor module (111) according to any one of claims 1 to 8, wherein the first switching element (14) is the IGBT (14) composed of a Si-based material and the second switching element (15) is the MOSFET (15) composed of a wide band gap semiconductor material.

Images