JP7233510B1 - power converter - Google Patents

Abstract

An object of the present invention is to provide a power conversion device that cools each of a plurality of semiconductor elements with a coolant having a uniform temperature, is easy to manufacture without increasing the number of parts, and has improved productivity. A base plate, a plurality of first semiconductor elements arranged side by side in a second direction on one side of the base plate in a first direction, and a plurality of first semiconductor elements arranged in a second direction on the other side of the base plate in the first direction. a plurality of second semiconductor elements arranged side by side; has a slit extending in the second direction between the first semiconductor element and the second semiconductor element, and a through hole penetrating the wall on one side of the slit in the second direction, and in the coolant flow path and a partition portion that partitions the space between the slit and the through-hole with a gap on one side in the first direction and a gap on the other side in the first direction, and one of the slit and the through-hole is a coolant flow path. One is a supply port and the other is a refrigerant discharge port. [Selection drawing] Fig. 3

Description

The present application relates to a power converter.

2. Description of the Related Art An electric vehicle such as an electric vehicle or a hybrid vehicle that uses a motor as a drive source is equipped with a plurality of power converters. A power converter is a device that converts an input current from DC to AC, AC to DC, or an input voltage to a different voltage. Specifically, a charger that converts a commercial AC power source into a DC power source to charge a high-voltage battery, a DC/DC converter that converts the DC power source of the high-voltage battery into a battery voltage (for example, 12 V) for auxiliary equipment, and a battery and an inverter for converting DC power from the motor into AC power for the motor.

Power converters installed in electric vehicles or hybrid vehicles are required to be smaller and have higher output. 2. Description of the Related Art As the output of a power converter increases, a plurality of semiconductor elements and capacitors accommodated in the power converter handle large currents, and the amount of heat generated by the plurality of semiconductor elements and capacitors is increasing. Therefore, the power conversion device is provided with a cooling structure for cooling a plurality of semiconductor elements and capacitors with a coolant.

When cooling a plurality of heat-generating semiconductor elements with a coolant, it is preferable to avoid a specific semiconductor element from becoming hot and reduce temperature variations among the plurality of semiconductor elements. However, when a cooling passage through which a coolant flows in the longitudinal direction is arranged directly under a plurality of semiconductor devices arranged in the longitudinal direction, the coolant used for cooling one semiconductor device is used for cooling another semiconductor device. , the semiconductor device that is cooled first is sufficiently cooled, but the semiconductor device that is cooled later is not sufficiently cooled. As a result, there is a problem that temperature variations among the plurality of semiconductor elements increase. A structure for avoiding such problems has been disclosed (see, for example, Patent Document 1). In the disclosed structure, a part called a separator is installed together with a cooling jacket to divide the coolant in the middle of the flow path and cool each of the plurality of semiconductor elements with the coolant at a uniform temperature.

WO2016/117094

In Patent Literature 1, since the coolant is divided in the middle of the flow path by the separator, each of the plurality of semiconductor elements can be cooled by the coolant with a uniform temperature. However, since the separator, which requires airtightness, is installed in the portion of the flow path, there is a problem that the number of parts and the number of man-hours for installation are increased. An increase in the number of parts and the number of man-hours required for installation may lead to an increase in the weight and cost of the power converter. In addition, since the separator is installed inside the cooling jacket while ensuring the airtightness of the flow paths on the upstream and downstream sides, the cooling jacket usually does not have enough space from the viewpoint of reducing the size and weight of the power converter. There is a problem that it is difficult to seal the coolant on the surface of the separator that is in contact with the inlet/outlet in the cooling jacket.

Accordingly, an object of the present application is to obtain a power converter that cools each of a plurality of semiconductor elements with a coolant having a uniform temperature, is easy to manufacture without increasing the number of parts, and improves productivity.

A power conversion device disclosed in the present application includes a base plate formed in a plate shape, a specific direction parallel to one surface of the base plate as a first direction, and a first direction parallel to one surface of the base plate and a plurality of first semiconductor elements arranged side by side in the second direction on one side of the first direction on one surface of the base plate; On the other side of the direction, a plurality of second semiconductor elements arranged side by side in the second direction and a wall facing the other surface of the base plate with a gap therebetween are provided to form a coolant channel through which the coolant flows. and a flow path forming member, the wall penetrating the wall between the plurality of first semiconductor elements and the plurality of second semiconductor elements when viewed in a direction perpendicular to the one surface of the base plate. It has one or more divided slits extending in two directions, and a through hole penetrating the wall at a portion on one side of the wall in the second direction from the slit, and the slit and the through hole are provided in the coolant channel. and a partition extending in the first direction with a gap on one side in the first direction and a gap on the other side in the first direction between and the other of the slit and the through-hole is a discharge port for discharging the coolant from the coolant channel.

According to the power converter disclosed in the present application, the wall of the flow path forming member has a slit penetrating through the wall and a through hole penetrating through the wall, and the wall, the plurality of semiconductor elements, and the plurality of second 2. The cooling medium flow channel, which is the space between the base plate on which the semiconductor element is provided, has a partitioning part that separates the slit and the through hole, and one of the slit and the through hole supplies the cooling medium to the cooling medium flow channel. Since the other of the slit and the through hole is an outlet for discharging the coolant from the coolant channel, the coolant that has flowed into the coolant channel is divided, and the coolant once used to cool the semiconductor element is discharged to other semiconductor elements. Therefore, it is possible to cool each of the plurality of first semiconductor elements and the plurality of second semiconductor elements with a coolant having a uniform temperature. In addition, since the slit and the through hole are formed in the flow path forming member and the partition part is provided in the coolant flow path, the power conversion device can be easily manufactured without increasing the number of parts and has improved productivity. be able to.

1 is a top view of a power converter according to Embodiment 1; FIG. 1 is a top view of a power converter according to Embodiment 1; FIG. FIG. 2 is a cross-sectional view of the power conversion device taken along line AA in FIG. 1; FIG. 2 is a cross-sectional view of the power conversion device cut at the BB cross-sectional position of FIG. 1; 4 is a top view of another power conversion device according to Embodiment 1. FIG. 1 is a perspective view of a main part of a power converter according to Embodiment 1; FIG. It is a sectional view explaining a power converter of a comparative example. FIG. 10 is a top view of a power conversion device according to Embodiment 2; FIG. 11 is a top view of another power conversion device according to Embodiment 2; FIG. 11 is a top view of a power conversion device according to Embodiment 3; FIG. 11 is a cross-sectional view of the power converter taken along line CC of FIG. 10; FIG. 11 is a bottom view of a power conversion device according to Embodiment 3; FIG. 11 is a bottom view of another power converter according to Embodiment 3;

Power converters according to embodiments of the present application will be described below with reference to the drawings. In each figure, the same or corresponding members and parts are denoted by the same reference numerals.

Embodiment 1.
1 is a top view of the power conversion device 100 according to Embodiment 1, FIG. 2 is a top view of the power conversion device 100, and is a view with the base plate 2 and the semiconductor module 3 removed from FIG. 1, and FIG. 1, FIG. 4 is a cross-sectional view of the power converter 100 cut along the line BB in FIG. 1, and FIG. 6 is a top view of the power conversion device, with the base plate 2 and the semiconductor module 3 removed from FIG. 1, and FIG. The power conversion device 100 is a device having a switching circuit for controlling power, and converts an input current from DC to AC, vice versa, or an input voltage to a different voltage.

<Power conversion device 100>
The power conversion device 100 includes a plate-shaped base plate 2, a plurality of first semiconductor elements 14, a plurality of second semiconductor elements 15, and a flow path forming member 1a. A specific direction parallel to one surface of the base plate 2 is defined as a first direction, and a direction orthogonal to the first direction parallel to one surface of the base plate 2 is defined as a second direction. In FIG. 1, arrow A indicates the first direction and arrow B indicates the second direction. The base plate 2 is formed, for example, in a rectangular plate shape, and each side of one surface of the base plate 2 is arranged parallel to the first direction or the second direction. When the base plate 2 is formed in a rectangular plate shape, the first semiconductor element 14 and the second semiconductor element 15 can be efficiently arranged side by side on one surface of the base plate 2, so that the power conversion device 100 can be miniaturized. . The base plate 2 is made of metal with high thermal conductivity such as aluminum.

In FIG. 1, outlines of the first semiconductor element 14 and the second semiconductor element 15 are indicated by dashed lines. The plurality of first semiconductor elements 14 are arranged side by side in the second direction on one side of the base plate 2 in the first direction. The plurality of second semiconductor elements 15 are arranged side by side in the second direction on one surface of the base plate 2 on the other side in the first direction. Although the first semiconductor element 14 is arranged on one side in the first direction and the second semiconductor element 15 is arranged on the other side in the first direction in the present embodiment, the first semiconductor element 14 is arranged on the other side in the first direction. However, the second semiconductor element 15 may be arranged on one side in the first direction.

The power converter 100 includes a plurality of semiconductor modules 3 formed from one or more first semiconductor elements 14 and one or more second semiconductor elements 15 . The plurality of semiconductor modules 3 are thermally connected to one surface of the base plate 2 and arranged side by side in the second direction. In the present embodiment, one semiconductor module 3 is formed from semiconductor elements 13a and 13b, which are the first semiconductor elements 14, and semiconductor elements 13c, 13d, which are the second semiconductor elements 15. A module 3 is provided. The number of semiconductor elements included in the semiconductor module 3 is not limited to this, and the number of semiconductor modules 3 included in the power converter 100 is not limited to this. Further, in the present embodiment, the semiconductor modules 3 are formed in a rectangular parallelepiped shape and arranged side by side in the same direction. By arranging the semiconductor modules 3 in the same direction, the power converter 100 can be miniaturized.

An internal configuration example of the semiconductor module 3 will be described with reference to FIG. Semiconductor elements 13 a and 13 b are electrically connected to one surface of conductive member 21 by solder 22 . The semiconductor element 13a is, for example, an IGBT (Insulated Gate Bipolar Transistor), and the semiconductor element 13b is, for example, a diode. The conductive member 21 is a metal plate having electrical conductivity and excellent thermal conductivity, and is made of copper, for example. The other surface of conductive member 21 is thermally connected to one surface of base plate 2 via insulating material 20 . The insulating material 20 is, for example, an insulating ceramic resin material. The semiconductor elements 13 a , 13 b , 13 c , 13 d , the conductive member 21 and the insulating material 20 are sealed with a sealing member 23 . A surface of the insulating material 20 opposite to the surface connected to the conductive member 21 is exposed from the sealing member 23 . The sealing member 23 is, for example, mold resin.

In this embodiment, an example in which the power conversion device 100 constitutes a three-phase AC inverter will be described. The configuration of the power converter 100 is not limited to a three-phase AC inverter, and may be a power converter incorporating a double three-phase inverter or a DCDC converter. A coolant flow path 11, which will be described later, is suitable for a power conversion device having a plurality of semiconductor elements, and thus its usage example is not limited. When the power conversion device 100 is a three-phase AC inverter, the first semiconductor element 14 is an element forming an upper arm, and the second semiconductor element 15 is an element forming a lower arm. The power converter 100 converts the supplied direct current into alternating current and supplies the converted three-phase (U-phase, V-phase, W-phase) alternating current to a load. Each of the U-phase, V-phase, and W-phase layers is composed of two arms, an upper arm and a lower arm. One of the three semiconductor modules 3 corresponds to the U phase, V phase, and W phase. The semiconductor elements 13a and 13b are not limited to IGBTs and diodes, and may be field effect transistors (MOSFET: Metal-Oxide-Semiconductor Field-Effect Transistor).

As shown in FIG. 3, the flow path forming member 1a has a wall 5 facing the other surface of the base plate 2 with a gap therebetween. A coolant channel 11 through which coolant flows is formed in the spaced portion. Water or ethylene glycol liquid is used as the coolant, for example. The first semiconductor element 14 and the second semiconductor element 15 in the semiconductor module 3 are cooled by the refrigerant flowing through the refrigerant flow path 11, and the heat generation of the first semiconductor element 14 and the second semiconductor element 15 is suppressed. A housing 1 is formed by a flow path forming member 1a and side walls 1b provided around the flow path forming member 1a. The housing 1 accommodates the base plate 2 , the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 . The flow path forming member 1a and the side walls 1b are made of aluminum, for example. The structure for sealing the coolant in the coolant channel 11 is, for example, a structure in which an O-ring is installed between the channel-forming member 1a and the base plate 2, and sealing is performed using elastic deformation of the O-ring. The channel forming member 1a and the base plate 2 may be welded and sealed using friction stir welding (FSW). These sealing structures are not shown because they are common cooling structures using coolant.

The power conversion device 100 includes first cooling fins 4a and second cooling fins 4b. The first cooling fins 4 a are provided on a portion of the other surface of the base plate 2 overlapping at least the plurality of first semiconductor elements 14 when viewed in a direction perpendicular to the other surface of the base plate 2 . The second cooling fins 4 b are provided on a portion of the other surface of the base plate 2 overlapping at least the plurality of second semiconductor elements 15 when viewed in a direction perpendicular to the other surface of the base plate 2 . The first cooling fins 4a and the second cooling fins 4b are prismatic fins integrally formed with the base plate 2, for example. The first cooling fins 4a and the second cooling fins 4b are not limited to prismatic fins, and may be pin fins or parallel fins, and the pin shape is not specified in this application. By providing the first cooling fins 4a and the second cooling fins 4b, the heat dissipation of the first semiconductor element 14 and the second semiconductor element 15 can be improved.

<Comparative example>
Prior to description of the coolant channel 11, a coolant channel 110 of a comparative example will be described. FIG. 7 is a cross-sectional view for explaining a power conversion device 200 of a comparative example, and is a view of the power conversion device 200 cut at the same position as in FIG. In FIG. 7, the coolant flows from left to right in the coolant channel 110 in the direction of the arrow. The coolant first cools the first semiconductor element 14 and then cools the second semiconductor element 15 . Since the second semiconductor element 15 is cooled by the coolant whose temperature is increased by cooling the first semiconductor element 14, the cooling of the second semiconductor element 15 becomes insufficient. Therefore, in the configuration shown in the comparative example, the temperature of the second semiconductor element 15 becomes higher than that of the first semiconductor element 14 .

<Refrigerant flow path 11>
The coolant channel 11, which is the main part of the present application, will be described. The wall 5 has slits 12 and through holes 8, as shown in FIG. The slits 12 are provided between the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 when viewed in a direction perpendicular to one surface of the base plate 2, as shown in FIG. The slit 12 penetrates the wall 5, extends in the second direction, and is divided into one or a plurality of slits. In this embodiment, as shown in FIG. 2, three divided slits 12a, 12b, and 12c are provided, but one undivided slit may be provided. The through hole 8 is provided through the wall 5 at a portion of the wall 5 on one side of the slit 12 in the second direction. A partition portion 9 is provided in the coolant channel 11 . The partition part 9 extends in the first direction and partitions the slit 12 and the through hole 8 with a gap on one side in the first direction and a gap on the other side in the first direction. The partition part 9 is integrated with one of the base plate 2 and the flow path forming member 1a. Since the partition part 9 is provided inside the refrigerant flow path 11 , sealing is not required at the place where the partition part 9 is arranged. One of the slit 12 and the through hole 8 is a supply port for supplying coolant to the coolant channel 11 , and the other of the slit 12 and the through hole 8 is a discharge port for discharging the coolant from the coolant channel 11 .

One or more slit partitions 6 are provided in the coolant channel 11 . The slit partition section 6 is provided at one or a plurality of locations in the second direction in the region where the slits 12 are provided. The slit partition part 6 extends in the first direction with a gap on one side in the first direction and a gap on the other side in the first direction, and partitions the one side and the other side in the second direction. The slit partitioning portion 6 is integrated with one of the base plate 2 and the flow path forming member 1a. In the present embodiment, two slit partitions 6a and 6b are provided in the coolant channel 11, but the number of the slit partitions 6 is not limited to this, and the power conversion device 100 has the slit partitions 6. It does not matter if the configuration is not

2, 3, and 6 for the case where the slit 12 is the supply port and the through hole 8 is the discharge port. The arrows shown in FIGS. 2, 3 and 6 indicate the direction in which the coolant flows. When the coolant flows into the coolant channel 11 from the slit 12, after the coolant flows from the slit 12 into the coolant channel 11, as shown in FIG. It is divided into the second refrigerant flowing on the side of the cooling fins 4b. As shown in FIG. 2 , the first coolant passes through the gap on one side in the first direction at the end of the partition portion 9 and is discharged from the through hole 8 . The second coolant passes through the gap on the other side in the first direction at the end of the partition portion 9 and is discharged from the through hole 8 . As shown in FIG. 3, the plurality of first semiconductor elements 14 are cooled by the first cooling medium flowing along the side of the first cooling fins 4a. The plurality of second semiconductor elements 15 are cooled by the second coolant flowing on the side of the second cooling fins 4b. In this embodiment, the first refrigerant and the second refrigerant are discharged from one through-hole 8, but the invention is not limited to this. Two through-holes 8 may be provided, and the first refrigerant and the second refrigerant may be separately discharged from each through-hole 8 .

The partition part 9 suppresses the first coolant from flowing back to the second cooling fin 4b side, and suppresses the second coolant from flowing back to the first cooling fin 4a side. The first coolant used for cooling the plurality of first semiconductor elements 14 is not used for cooling the plurality of second semiconductor elements 15, and the second coolant used for cooling the plurality of second semiconductor elements 15 is not used for cooling the plurality of second semiconductor elements 15. is not used for cooling the first semiconductor element 14 of the . With this configuration, the coolant that has flowed into the coolant channel 11 is divided, and the coolant once used to cool one of the semiconductor elements can be prevented from passing through the side of the other semiconductor elements. Each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be cooled with a coolant having a uniform temperature. The slits 12 and the through-holes 8 are formed in the flow path forming member 1a, the partitions 9 are provided in the refrigerant flow paths 11, and the partitions 9 are integrally formed with the base plate 2 or the flow path forming member 1a. Therefore, it is possible to obtain the power converter 100 which is easy to manufacture without increasing the number of parts and which has improved productivity.

In the configuration of this embodiment in which the two slit partitions 6a and 6b are provided, as shown in FIG. 6, the area of the coolant channel 11 provided with the slit 12 is divided into three. The first coolant that has flowed into the coolant channel 11 from the slit 12 a passes through the gap on one side in the first direction at the end of the slit partition 6 a toward the through hole 8 . The first coolant that has flowed into the coolant channel 11 from the slit 12b passes through the gap on one side in the first direction at the end of the slit partition portion 6b toward the through hole 8 . The first coolant that has flowed into the coolant flow path 11 from the slit 12 c passes through the gap on one side in the first direction at the end of the partition portion 9 toward the through hole 8 . The second coolant that has flowed into the coolant channel 11 from the slit 12 a passes through the gap on the other side in the first direction at the end of the slit partition 6 a toward the through hole 8 . The second coolant that has flowed into the coolant channel 11 from the slit 12b passes through the gap on the other side in the first direction at the end of the slit partition 6b toward the through hole 8 . The second coolant that has flowed into the coolant channel 11 from the slit 12c passes through the gap on the other side in the first direction at the end of the partition portion 9 toward the through hole 8 . By providing the slit partitions 6, the coolant is further divided, and it is possible to further prevent the coolant once used for cooling from passing through other cooling fins. Each of the second semiconductor elements 15 can be further cooled with a uniform temperature coolant. The slit partitioning portion 6 is provided in the coolant channel 11 and is formed integrally with the base plate 2 or the channel forming member 1a. A power conversion device can be obtained.

In this embodiment, the slit partitions 6a and 6b are arranged between the plurality of semiconductor modules 3 when viewed in a direction perpendicular to one surface of the base plate 2, as shown in FIG. By configuring in this way, since the coolant does not flow to the locations where the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are not arranged, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are efficiently cooled. The semiconductor element 15 can be cooled.

In the present embodiment, as shown in FIG. 2, a slit partitioning portion 6 is provided at the divided portion of the slit 12 . By configuring in this way, the slit partitioning portion 6 can be easily integrated with the flow path forming member 1a. Moreover, the slit partitioning portion 6 can be integrated with the flow path forming member 1a with high strength.

In the present embodiment, as shown in FIG. 1, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are arranged in a row. With this configuration, the coolant that has flowed directly under any semiconductor element to cool the semiconductor element does not flow directly under the other semiconductor element to cool the other semiconductor element. Each of the one semiconductor element 14 and the plurality of second semiconductor elements 15 can be cooled with a coolant having a uniform temperature. If it is difficult to arrange the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 in a line due to the arrangement space, at least the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 14 Preferably, each of the elements 15 has the same number. If the numbers are the same, the heat generation amounts of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be equalized.

In the present embodiment, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are the same number. By configuring in this way, the unevenness in the degree of heat generation between the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 is reduced, so that the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 14 15 can be efficiently cooled with a coolant of uniform temperature. Moreover, if the degrees of heat generation of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are approximately the same, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be evenly cooled. The amount of heat generated by each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be made uniform.

The flow of the coolant in the coolant channel 11 will be described with reference to FIG. 5 in the case where the through hole 8 is the supply port and the slit 12 is the discharge port. The arrows shown in FIG. 5 indicate the direction in which the coolant flows. When the coolant flows into the coolant channel 11 from the through hole 8 , the coolant flows into the coolant channel 11 from the through hole 8 and then passes through the gap on one side in the first direction at the end of the partition portion 9 . 3 refrigerant and a fourth refrigerant passing through the gap on the other side in the first direction at the end of the partition portion 9 . The third coolant passes through the coolant channel 11 on the side of the first cooling fins 4 a and is discharged from the slit 12 . The fourth coolant passes through the coolant channel 11 on the side of the second cooling fins 4 b and is discharged from the slit 12 . The plurality of first semiconductor elements 14 are cooled by the third coolant flowing on the side of the first cooling fins 4a. The plurality of second semiconductor elements 15 are cooled by the flow of the fourth coolant on the side of the second cooling fins 4b.

Even if the through hole 8 is used as the supply port and the slit 12 is used as the discharge port, the same effect as when the through hole 8 is used as the discharge port and the slit 12 is used as the supply port can be obtained. Either the slit 12 or the through hole 8 can be selected as the supply port or the discharge port depending on the configuration and arrangement of the parts connected to the coolant flow path 11 outside the housing 1 .

The housing 1 is manufactured, for example, by casting. By providing a mold with a portion where the slit 12 is formed and casting the housing 1, the slit 12 can be formed at low cost without requiring an additional manufacturing process. In addition, since the slit 12 is integrated with the housing 1, there is no possibility that the position of the slit 12 will shift during the manufacturing process of the housing 1. For example, if the power conversion device 100 is a power conversion device for a hybrid vehicle, the housing 1 is often a metal housing having a large thickness, and thus has high strength, and there is no fear that the slits 12 will be deformed. Furthermore, since the refrigerant pressure is high in the portion of the refrigerant channel where the cooling fins are formed, high strength is required. The cost of the power conversion device 100 can be reduced because reinforcement of the formed coolant channel portion is not required.

With the first coolant and the second coolant, or the third coolant and the fourth coolant, which are divided coolants, the plurality of first semiconductor elements 14 side and the plurality of second semiconductor elements 15 side always have the same temperature. Since the coolant is supplied, variations in temperature between the first semiconductor element 14 and the second semiconductor element 15 can be reduced. In a power conversion device in which the upper and lower arms are driven by an inverter, the upper and lower arms generally use the same semiconductor element, so that the upper and lower arms generate approximately the same amount of heat. Therefore, by always supplying the coolant with the same temperature to the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15, it is possible to reduce the temperature variation between the upper and lower arms.

In this embodiment, the first semiconductor element 14 is an element forming an upper arm and the second semiconductor element 15 is an element forming a lower arm, but the present invention is not limited to this. If the semiconductor elements are evenly arranged in the respective portions through which the divided coolant flows, the equally arranged semiconductor elements are cooled equally. Therefore, the first semiconductor element 14 may be an element forming the lower arm, and the second semiconductor element 15 may be an element forming the upper arm. Alternatively, the semiconductor element forming the upper arm and the semiconductor element forming the lower arm may be arranged in a mixed manner in the divided portions through which the coolant flows. For example, the layout of the semiconductor elements in the semiconductor module 3 in FIG. 1 may be rotated by 90 degrees when viewed from the top of the paper.

In this embodiment, examples of the first semiconductor element 14 and the second semiconductor element 15 are an IGBT, a diode, or a MOSFET, but they are not limited to these. Other elements may be used as long as they generate heat by flowing. Although it is desirable that the number of elements forming the plurality of first semiconductor elements 14 and the number of elements forming the plurality of second semiconductor elements 15 be the same, the number is not particularly limited.

When the power conversion device 100 is a power conversion device for a hybrid vehicle, the power conversion device 100 individually monitors the temperatures of a plurality of semiconductor elements, and when the temperature of a certain semiconductor element exceeds a predetermined temperature, power conversion is performed. Equipped with a protection system that limits the output of the device. An on-chip temperature sensor using a diode, for example, is used to measure the temperature of a semiconductor element. In the comparative example shown in FIG. 7, when the temperature of the insufficiently cooled second semiconductor element 15 rises, the first semiconductor element 14 is protected for the second semiconductor element 15 even though there is a margin in the temperature of the first semiconductor element 14 . The system works. When the protection system is activated, the output of the power converter cannot be sufficiently exhibited. In this case, the load is switched from the motor drive to the engine drive prematurely, which may hinder improvement in the fuel efficiency of the automobile and adversely affect the ride comfort such as the acceleration performance.

The power converter 100 shown in Embodiment 1 is particularly suitable for such a hybrid vehicle. If the temperature variation of a plurality of semiconductor elements is reduced as in the power conversion device 100 of Embodiment 1, it becomes unnecessary to determine the size of the semiconductor elements according to the downstream side where the coolant temperature is high. Since the size of the semiconductor element is not determined according to the downstream side where the coolant temperature is high, the size of the semiconductor element can be reduced. Further, in the prior art, a separator was added to the coolant channel, but the slit 12 and the through hole 8 are formed in the channel forming member 1a, and the partition portion 9 is integrated with the base plate 2 or the channel forming member 1a. 7, the cooling medium can be divided without increasing the number of parts compared to the comparative example shown in FIG. In addition, since the cooling efficiency of each of the plurality of semiconductor elements is increased, the discharge capacity required for the cooling pump that supplies the coolant can be reduced. Since the number of parts does not increase and the discharge capacity of the cooling pump can be reduced, the cost of the power conversion device 100 can be reduced, and the weight of the vehicle equipped with the power conversion device 100 can be reduced and the fuel efficiency can be improved.

As described above, in the power converter 100 according to Embodiment 1, the wall 5 of the flow path forming member 1a has the slit 12 penetrating the wall 5 and the through hole 8 penetrating the wall 5, A partition portion 9 that separates the slit 12 and the through hole 8 in the coolant flow path 11, which is a portion between the wall 5 and the base plate 2 on which the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are provided. , one of the slit 12 and the through hole 8 is a supply port for supplying the coolant to the coolant channel 11, and the other of the slit 12 and the through hole 8 is a discharge port for discharging the coolant from the coolant channel 11 , the coolant flowing into the coolant flow path 11 is divided, and the coolant once used for cooling the semiconductor elements can be prevented from passing through the side of other semiconductor elements. Each of the second semiconductor elements 15 can be cooled with a coolant having a uniform temperature. In addition, since the slit 12 and the through hole 8 are formed in the flow path forming member 1a, and the partition portion 9 is provided in the coolant flow path 11 and integrally formed with the base plate 2 or the flow path forming member 1a, It is possible to obtain the power conversion device 100 which is easy to manufacture without increasing the number of parts and has improved productivity.

In the region where the slits 12 of the coolant flow path 11 are provided, the power conversion device 100 has a gap on one side in the first direction and a gap on the other side in the first direction at one or a plurality of places in the second direction. In the state provided, if there is a single or a plurality of slit partitions 6 that extend in the first direction and partition one side and the other side in the second direction, the refrigerant is further divided, and the refrigerant once used for cooling can be further prevented from passing through the side of other cooling fins, so that each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be efficiently cooled with a coolant of even temperature. can. In addition, since the slit partition portion 6 is provided in the refrigerant channel 11 and is formed integrally with the base plate 2 or the channel forming member 1a, it is easy to manufacture without increasing the number of parts, and productivity is improved. An improved power converter can be obtained.

When the slit partition part 6 is arranged between the plurality of semiconductor modules 3 when viewed in the direction perpendicular to one surface of the base plate 2, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are arranged. Since the cooling medium does not flow to the places where the is not arranged, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be efficiently cooled. In addition, when the wall 5 has a plurality of slits 12 divided into a plurality of slits 12 and the slit partitioning portions 6 are provided at the divided portions of the slits 12, the slit partitioning portions 6 can be easily integrated with the flow path forming member 1a. In addition, the slit partitioning portion 6 can be integrated with the flow path forming member 1a with high strength.

When each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are arranged in a row, the coolant that has flowed directly under one of the semiconductor elements to cool the semiconductor element may Therefore, the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be cooled with a coolant having a uniform temperature. Further, when the number of the plurality of first semiconductor elements 14 and the number of the plurality of second semiconductor elements 15 are the same, the degrees of heat generation of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 are uneven. Since it becomes smaller, each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be cooled with a coolant having a uniform temperature.

The power conversion device 100 includes first cooling fins 4a provided on a portion of the other surface of the base plate 2 overlapping at least the plurality of first semiconductor elements 14 when viewed in a direction perpendicular to the other surface of the base plate 2. and a second cooling fin 4b provided on a portion of the other surface of the base plate 2 overlapping at least the plurality of second semiconductor elements 15 when viewed in a direction perpendicular to the other surface of the base plate 2. In this case, the heat dissipation properties of the first semiconductor element 14 and the second semiconductor element 15 can be improved. Further, when the base plate 2 is formed in a rectangular plate shape and each side of one surface of the base plate 2 is arranged parallel to the first direction or the second direction, the first semiconductor element 14 and the second semiconductor Since the elements 15 can be efficiently arranged side by side on one surface of the base plate 2, the power conversion device 100 can be miniaturized.

Embodiment 2.
A power converter 100 according to Embodiment 2 will be described. 8 is a top view of a power conversion device 100 according to Embodiment 2, and FIG. 9 is a top view of another power conversion device 100 according to Embodiment 2. FIG. 8 and 9 are diagrams showing the power conversion device 100 with the base plate 2 and the semiconductor module 3 removed. The power converter 100 according to the second embodiment has a configuration in which the width of the slit 12 is different from that of the power converter 100 shown in the first embodiment.

In the power conversion device 100 shown in FIGS. 8 and 9 , the slit 12 is a supply port for supplying coolant to the coolant channel 11 and the through hole 8 is a discharge port for discharging the coolant from the coolant channel 11 . The slit 12 has a width larger on one side in the second direction than on the other side in the second direction. Since the slit 12 is a supply port and the coolant flows in the second direction, the coolant is supplied to the slit 12 from the left side of the drawing. Therefore, the pressure of the refrigerant tends to increase in the slit 12a on the left side of the drawing. If the widths of the slits 12 are the same, there is a risk that a large amount of coolant will flow through the slits 12 where the pressure of the coolant is high. By making the width of the slit 12 larger on one side in the second direction than on the other side in the second direction, a uniform amount of coolant can flow in each portion of the coolant channel 11 . When a uniform amount of coolant flows through each portion of the coolant flow path 11, each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 can be cooled with the coolant having a more uniform temperature.

The width of the slit 12 becomes wider toward the one side in the second direction than the other side in the second direction continuously or stepwise. The width of the slit 12 shown in FIG. 8 increases continuously, and the width of the slit 12 illustrated in FIG. 9 increases stepwise. With this configuration, the wall 5 can be easily formed with the slit 12 having a larger width on one side in the second direction than on the other side in the second direction. Further, when the coolant channel 11 has the slit partitions 6 , a uniform amount of coolant can easily flow in each part of the coolant channel 11 partitioned by the slit partitions 6 .

Embodiment 3.
A power converter 100 according to Embodiment 3 will be described. 10 is a top view of the power conversion device 100 according to Embodiment 3, FIG. 11 is a cross-sectional view of the power conversion device 100 cut along the CC cross-section position of FIG. 10, FIG. 12 is a bottom view of the power conversion device 100, FIG. 13 is a bottom view of another power conversion device 100 according to Embodiment 3. FIG. A power converter 100 according to Embodiment 3 is configured to include a smoothing capacitor 10 and a cooling jacket 7 .

As shown in FIG. 10, the smoothing capacitor 10 is accommodated in the housing 1 and thermally connected to the flow path forming member 1a. Smoothing capacitor 10 is electrically connected to each of three semiconductor modules 3 . The smoothing capacitor 10 is provided between the power supply and the semiconductor module 3 to smooth DC power.

As shown in FIG. 11, the cooling jacket 7 is provided on the opposite side of the flow path forming member 1a from the coolant flow path 11 side. A second coolant channel 7a through which coolant flows is formed in the space between the cooling jacket 7 and the channel forming member 1a. The second coolant channel 7a includes a first portion opposite to the portion of the channel forming member 1a provided with the smoothing capacitor 10, and a portion of the channel forming member 1a provided with the coolant channel 11. It has a second portion which is the portion opposite to the . A second coolant channel 7 a formed in the second portion is connected to at least one of the slit 12 and the through hole 8 . Since the second coolant channel 7a is connected to one of the slit 12 and the through hole 8, the second coolant channel 7a and the coolant channel 11 are in communication. In the power conversion device 100 shown in FIG. 12, the second coolant channel 7a and the slit 12 are connected. In the power conversion device 100 shown in FIG. 13 , the second coolant flow paths 7a are connected to the slits 12 and the through holes 8 . With this configuration, each of the smoothing capacitor 10, the plurality of first semiconductor elements 14, and the plurality of second semiconductor elements 15 is cooled by the refrigerant continuously flowing through the second refrigerant flow path 7a and the refrigerant flow path 11. Allow to cool.

The cooling jacket 7 is made of aluminum, for example. The cooling jacket 7 is, for example, a single plate having recesses and projections formed by press molding. By configuring the cooling jacket 7 with one member, the cost of the power converter 100 can be suppressed. The recessed portion and the projecting portion form the cooling jacket 7 with a second coolant channel 7a and a non-channel portion 7b that does not become the second coolant channel 7a. The cooling jacket 7 is attached to the flow path forming member 1a at the non-flow path portion 7b. The cooling jacket 7 is attached by, for example, sealing agent and screwing so that the coolant can be sealed. By attaching the cooling jacket 7 to the channel forming member 1a, a second coolant channel 7a communicating with the coolant channel 11 is formed. The cooling jacket 7 has an inlet 7c for supplying the coolant to the second coolant channel 7a and an outlet 7d for discharging the coolant. The refrigerant flowing into the second refrigerant passage 7a from the inlet 7c flows through the second refrigerant passage 7a side (first portion) of the portion of the passage forming member 1a to which the smoothing capacitor 10 is thermally connected. After that, the coolant flows into the coolant channel 11 through the slit 12 or the through hole 8 .

The flow of coolant in the power converter 100 shown in FIG. 12 will be described. The coolant flows into the second coolant channel 7a from the inlet 7c and flows through the first portion to cool the smoothing capacitor 10 first. The coolant flows from the second portion through the slits 12 into the coolant channel 11, and cools the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 with the coolant having a uniform temperature. The coolant is discharged to the outside through the through hole 8 and the discharge port 7d. The coolant flow in the coolant channel 11 is the same as the coolant flow shown in FIG.

The flow of coolant in the power converter 100 shown in FIG. 13 will be described. The coolant flows into the second coolant channel 7a from the inlet 7c and flows through the first portion to cool the smoothing capacitor 10 first. The coolant flows into the coolant channel 11 through the through-holes 8 and cools each of the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 with the coolant having a uniform temperature. Coolant flows through the slit 12 into the second portion. The refrigerant is discharged to the outside through the discharge port 7d. The coolant flow in the coolant channel 11 is the same as the coolant flow shown in FIG.

Normally, heat generation in the smoothing capacitor 10 is smaller than heat generation in the plurality of first semiconductor elements 14 and the plurality of second semiconductor elements 15 . Therefore, the temperature rise of the coolant that cools the smoothing capacitor 10 is relatively small. Overall cooling can be optimized.

In the power conversion device 100 shown in FIG. 12, the cooling jacket 7 is formed with the discharge port 7d of the coolant as the power conversion device 100, but the cooling jacket 7 is not limited to this. A structure in which the coolant is directly discharged to the outside from the through hole 8 may be used. In the power conversion device 100 shown in FIG. 13, the cooling jacket 7 is formed with the discharge port 7d of the refrigerant as the power conversion device 100, but it is not limited to this. A structure in which the coolant is directly discharged to the outside from the slit 12 may be used. In the power conversion device 100 shown in FIG. 13 , when the coolant is directly discharged to the outside from the slit 12 portion, the second coolant flow path 7 a is connected only to the through hole 8 . This is because the second coolant channel 7a is not formed between the slit 12 and the discharge port 7d.

Also, while this application has described various exemplary embodiments and examples, various features, aspects, and functions described in one or more of the embodiments may vary from particular embodiment to specific embodiment. The embodiments are applicable singly or in various combinations without being limited to the application.
Accordingly, numerous variations not illustrated are envisioned within the scope of the technology disclosed herein. For example, modification, addition or omission of at least one component, extraction of at least one component, and combination with components of other embodiments shall be included.

Reference Signs List 1 housing 1a flow path forming member 1b side wall 2 base plate 3 semiconductor module 4a first cooling fin 4b second cooling fin 5 wall 6 slit partition 7 cooling jacket 7a second coolant flow path, 7b non-flow path portion, 7c inlet, 7d outlet, 8 through hole, 9 partition, 10 smoothing condenser, 11 refrigerant flow path, 12 slit, 12a, 12b, 12c slit, 13a, 13b, 13c, 13d Semiconductor element 14 First semiconductor element 15 Second semiconductor element 20 Insulating material 21 Conductive member 22 Solder 23 Sealing member 100 Power converter 110 Coolant flow path 200 Power converter

Claims (12)

a base plate formed in a plate shape;
A specific direction parallel to one surface of the base plate is defined as a first direction, a direction orthogonal to the first direction parallel to one surface of the base plate is defined as a second direction, and one surface of the base plate a plurality of first semiconductor elements arranged side by side in the second direction on one side of the first direction in
a plurality of second semiconductor elements arranged side by side in the second direction on the other side of the first direction on one surface of the base plate;
a flow path forming member having a wall facing the other surface of the base plate with a gap therebetween and forming a coolant flow path in which a coolant flows through the gap;
When viewed in a direction perpendicular to one surface of the base plate, the wall extends between the plurality of first semiconductor elements and the plurality of second semiconductor elements, penetrating the wall and extending in the second direction. a slit divided into one or a plurality of extending slits, and a through hole penetrating the wall at a portion of the wall on one side of the slit in the second direction,
Between the slit and the through-hole, the coolant channel extends in the first direction with a gap on one side in the first direction and a gap on the other side in the first direction. , having a partition part for partitioning,
one of the slit and the through hole is a supply port for supplying a coolant to the coolant channel;
The power conversion device, wherein the other of the slit and the through hole is a discharge port for discharging the coolant from the coolant channel. A gap on one side in the first direction and a gap on the other side in the first direction are provided at one or a plurality of positions in the second direction in the region in which the slit is provided in the coolant channel. 2 . The power conversion device according to claim 1 , further comprising a single or a plurality of slit partitions extending in the first direction and partitioning the one side and the other side in the second direction. a plurality of semiconductor modules formed from one or more of the first semiconductor elements and one or more of the second semiconductor elements;
the plurality of semiconductor modules are thermally connected to one surface of the base plate and arranged side by side in the second direction;
3. The power converter according to claim 2, wherein said slit partitioning portion is arranged between a plurality of semiconductor modules when viewed in a direction perpendicular to one surface of said base plate. The wall has the slit divided into a plurality,
4. The power conversion device according to claim 2, wherein the slit partitioning portion is provided at the dividing portion of the slit. The slit is a supply port for supplying a coolant to the coolant channel, the through hole is a discharge port for discharging the coolant from the coolant channel,
The power converter according to any one of claims 1 to 4, wherein the slit has a width larger on one side in the second direction than on the other side in the second direction. 6. The power converter according to claim 5, wherein the width of said slit is wider than the other side in said second direction continuously or stepwise toward one side in said second direction. The power conversion device according to any one of claims 1 to 6, wherein each of the plurality of first semiconductor elements and the plurality of second semiconductor elements are arranged in a line. The power converter according to any one of claims 1 to 7, wherein the plurality of first semiconductor elements and the plurality of second semiconductor elements are the same in number. a housing having the flow path forming member and housing the base plate, the plurality of first semiconductor elements, and the plurality of second semiconductor elements;
a smoothing capacitor housed in the housing and thermally connected to the flow path forming member;
a cooling jacket provided on the side opposite to the coolant channel side of the channel forming member and forming a second coolant channel through which a coolant flows in a space between the channel forming member;
The power converter according to any one of claims 1 to 8, wherein the second coolant channel is connected to one of the slit and the through hole. The coolant that has flowed into the second coolant channel flows through the second coolant channel side of the portion of the channel forming member to which the smoothing capacitor is thermally connected, and then through the slit or the through hole. 10. The power conversion device according to claim 9, wherein the coolant flows into the coolant channel. a first cooling fin provided on a portion of the other surface of the base plate that overlaps at least a plurality of the first semiconductor elements when viewed in a direction perpendicular to the other surface of the base plate;
and second cooling fins provided on a portion of the other surface of the base plate overlapping at least the plurality of second semiconductor elements when viewed in a direction perpendicular to the other surface of the base plate. 11. The power converter according to any one of 1 to 10. 12. Any one of claims 1 to 11, wherein the base plate is formed in a rectangular plate shape, and each side of one surface of the base plate is arranged parallel to the first direction or the second direction. The power conversion device according to .

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