阅读说明：本技术 电力变换装置 (Power conversion device ) 是由 小野公洋 熊仓晋 石井聪一 于 2019-02-21 设计创作，主要内容包括：电力变换装置具有：电力变换电路,其将输入电力变换为直流电力或交流电力；树脂制的基座部件,其供电力变换电路载置；罩部件,其在与基座部件之间对电力变换电路进行收容；冷媒流路,其设置于基底部件的内部,使得用于对电力变换电路进行冷却的冷媒流通；以及温度传感器,其设置于基底部件,对在冷媒流路内流通的冷媒的温度进行检测。该温度传感器具有至少包含热敏电阻在内的导电部件,导电部件的至少一部分被由绝缘性材料形成的树脂壁包围。(The power conversion device includes: a power conversion circuit that converts input power into direct-current power or alternating-current power; a resin base member on which a power conversion circuit is mounted; a cover member that houses the power conversion circuit between the cover member and the base member; a refrigerant flow path that is provided inside the base member and through which a refrigerant for cooling the power conversion circuit flows; and a temperature sensor provided in the base member and detecting a temperature of the refrigerant flowing through the refrigerant passage. The temperature sensor includes a conductive member including at least a thermistor, and at least a part of the conductive member is surrounded by a resin wall made of an insulating material.)

1. A power conversion device is provided with:

a power conversion circuit that converts input power into direct-current power or alternating-current power;

a resin base member on which the power conversion circuit is mounted;

a cover member that houses the power conversion circuit between the cover member and the base member;

a refrigerant flow path that is provided inside the base member and through which a refrigerant for cooling the power conversion circuit flows; and

a temperature sensor provided in the base member and detecting a temperature of the refrigerant flowing through the refrigerant passage,

the temperature sensor has a conductive member including at least a thermistor,

at least a part of the conductive member is surrounded by a resin wall formed of an insulating material.

2. The power conversion device according to claim 1,

the resin wall is a part of the temperature sensor and is configured as a housing portion that houses the conductive member,

the case portion is formed integrally with the base member made of resin.

3. The power conversion device according to claim 2,

the shell part is provided with a convex part which is protruded into the refrigerant flow path,

the thermistor is accommodated in the protruding portion.

4. The power conversion device according to claim 1,

the conductive member includes a metal housing portion that houses the thermistor,

the temperature sensor is configured such that, in a state of being mounted on the base member, a part of the metal case portion penetrates the base member and protrudes into the refrigerant flow path.

5. The power conversion device according to any one of claims 1 to 4,

the temperature sensor is disposed upstream of a position where the power conversion circuit is disposed in the refrigerant passage provided inside the base member.

Technical Field

The present invention relates to a power conversion device.

Background

JP5471685B discloses a power converter for cooling a semiconductor module with a refrigerant, in which a temperature sensor is provided in a cooling pipe through which the refrigerant flows to control the temperature of the semiconductor module as a cooling target, and the temperature of the refrigerant is constantly monitored.

Disclosure of Invention

Here, in order to accurately control the temperature of the semiconductor module as a cooling target, it is required to bring the temperature sensor as close as possible to the semiconductor module. In order to satisfy such a demand, it is conceivable to dispose the temperature sensor inside the power conversion device. However, when the temperature sensor is disposed inside the power converter, it is necessary to secure a predetermined insulation distance between the temperature sensor and the electronic components constituting the power converter, and therefore there is a problem that the size of the power converter becomes large.

An object of the present invention is to provide a technique that, when a temperature sensor is disposed inside a power conversion device, can ensure insulation between electronic components that constitute the power conversion device and the temperature sensor without increasing the size of the power conversion device.

A power conversion device according to an aspect of the present invention includes: a power conversion circuit that converts input power into direct-current power or alternating-current power; a resin base member on which the power conversion circuit is mounted; a cover member that houses the power conversion circuit between the cover member and the base member; a refrigerant passage provided inside the base member and through which a refrigerant for cooling the power conversion circuit flows; and a temperature sensor provided in the base member and detecting a temperature of the refrigerant flowing through the refrigerant passage. The temperature sensor has a conductive member including at least a thermistor, and at least a part of the conductive member is surrounded by a resin wall formed of an insulating material.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Drawings

Fig. 1 is a diagram illustrating a power conversion device according to embodiment 1.

Fig. 2 is a sectional view a-a of fig. 1.

Fig. 3 is a diagram illustrating a sub-section.

Fig. 4 is a diagram illustrating modification 1 of the power conversion device according to embodiment 1.

Fig. 5 is a diagram illustrating a manner of joining the metal cover and the metal plate in modification 1.

Fig. 6 is a diagram illustrating modification 2 of the power conversion device according to embodiment 1.

Fig. 7 is a diagram illustrating a power conversion device according to embodiment 2.

Fig. 8 is a diagram illustrating a power conversion device according to embodiment 3.

Fig. 9 is a perspective view showing a conventional power conversion device.

Fig. 10 is a diagram illustrating a conventional power conversion device.

Fig. 11 is a diagram illustrating a current temperature sensor.

Detailed Description

(embodiment 1)

Fig. 1 is a schematic configuration diagram for explaining a power conversion device 100 according to embodiment 1.

The power conversion device 100 includes a power module 2, a control board 3, a smoothing capacitor 4, a resin base member 5, a metal cover 7, and a temperature sensor 8. The base member 5 has a refrigerant passage 6 through which a refrigerant can flow. The power conversion device 100 is mounted on, for example, a vehicle having a motor, and functions as a vehicle-mounted power converter as a power supply unit for the motor.

The power module 2, the control board 3, and the smoothing capacitor 4 are mainly necessary electronic components for converting input power into predetermined power and outputting the power, and a circuit constituted by the electronic components is, for example, an inverter. Hereinafter, the electronic components are collectively referred to as a power conversion circuit 1. The power conversion circuit 1 is electrically connected to an external power source via an electric terminal (input terminal) not shown, and is connected to a motor not shown via another electric terminal (output terminal). The power conversion circuit 1 converts dc power supplied from the external power supply into ac power and supplies the ac power to the motor, or converts ac power supplied from the motor into dc power and supplies the dc power to the external power supply. Among the various electronic components included in the power conversion circuit 1 of the present embodiment, at least the power module 2 is placed on one surface (the upper surface in the present embodiment shown in fig. 1) of the base member 5, and is fixed to the base member 5 by a fixing bolt (not shown) or the like.

The base member 5 functions as a cooler for cooling the power conversion circuit 1. The base member 5 is formed of an insulating material. The base member 5 of the present embodiment is an electrically insulating resin, and for example, a polyphenylene sulfide (PPS) resin, a polyphthalamide (PPA) resin, or the like is used in consideration of strength.

The base member 5 includes a refrigerant passage (refrigerant pipe portion) 6 through which a refrigerant (e.g., cooling water) can flow. As the cooling water flowing through the cooling medium flow path 6, in the present embodiment, for example, a long-life cooling liquid (LLC) cooling medium is used. The base member 5 exchanges heat between the power conversion circuit 1 (particularly, the power module 2) mounted on one surface and the cooling water flowing through the refrigerant passage 6 formed inside, and cools the power conversion circuit 1.

The temperature sensor (water temperature sensor) 8 is configured to detect (measure) the temperature of the refrigerant flowing through the refrigerant passage 6 inside the power converter 100. Then, the power conversion device 100 controls the temperature of the cooling water so that the temperature of the power conversion circuit 1 converges to an appropriate temperature range, based on the detection value of the temperature sensor 8. The temperature sensor 8 of the present embodiment will be described in detail later with reference to fig. 2, 3, and the like.

The metal cover 7 functions as a case for accommodating the power conversion circuit 1 and the temperature sensor 8 disposed between the metal cover 7 and the base member 5 in the power conversion device 100. The metal cover 7 of the present embodiment is formed of a metal such as aluminum, for example. The metal cover 7 has a recess, and is fixed to the upper surface of the base member 5 using a fixing bolt or the like, not shown, so as to house the power conversion circuit 1 in the recess. As described above, in the power converter 100 of the present embodiment, the metal cover 7 and the base member 5 function as a case for housing the power conversion circuit 1. The base member 5 has not only the above-described cooling function but also a function as a part of a case for housing the power conversion circuit 1.

Here, problems of the conventional power conversion device will be described with reference to fig. 9 to 11.

Fig. 9 is a perspective view showing an example of a current configuration of an external appearance of a power conversion device applied to an electric vehicle. The illustrated power conversion device includes a water channel pipe 50, a weak current connector 51, an external weak current wiring 52, and a temperature sensor 53. The water channel pipe 50 is a pipe for introducing the refrigerant from the outside or discharging the refrigerant to the outside with respect to a refrigerant passage formed inside the power conversion device.

As shown in the drawing, in the present example of the power converter, the temperature sensor 53 is provided outside the power converter in the water passage pipe 50 to avoid the risk of water leakage inside the power converter, and is configured to directly detect the temperature of the refrigerant flowing inside the water passage pipe 50. The data signal relating to the detected temperature (water temperature) is transmitted to a control board (not shown) disposed inside the power converter through the external weak current wiring 52 and the weak current connector 51. In this case, since the distance between the temperature sensor 53 and the power conversion circuit as the cooling target incorporated in the power conversion device becomes long, there is a problem that the accuracy of the temperature control for the power conversion circuit performed based on the cooling water temperature detected by the temperature sensor 53 is lowered.

Further, when the temperature sensor 53 is disposed inside the power conversion device, the following problem occurs.

Fig. 10 is a diagram showing an example of a current structure relating to the inside of the power conversion device, and is a diagram illustrating a positional relationship between the temperature sensor 53 and an electronic component (power conversion circuit 1) incorporated in the power conversion device. In the present example shown in the drawing, the power conversion device houses a power conversion circuit 1 configured to include a power module 2, a control board 3, and a strong electric element connection unit 20 between a metal base member 54 and a metal cover 7, not shown. The base member 54 is provided therein with a refrigerant passage for flowing a refrigerant for cooling the power conversion circuit 1. The temperature sensor 53 is configured to detect the temperature of the refrigerant flowing through the refrigerant passage inside the power converter, as shown in the figure.

Here, the structure of the temperature sensor 53 will be described with reference to fig. 11. Fig. 11 is a schematic configuration diagram showing an example of the structure of a conventional temperature sensor (temperature sensor 53). Fig. 11(a) is a perspective view showing the appearance of the temperature sensor 53. Fig. 11(b) is a diagram illustrating an internal structure of the temperature sensor 53. As shown in fig. 11, the temperature sensor 53 is composed of the male connector portion 12 and the metal housing portion 13. The metal housing portion 13 is made of, for example, brass. A thermistor 17 is disposed in an internal space near an end (distal end) of the metal case portion 13 on the distal end side (opposite side to the male connector portion 12), and the thermistor 17 is an electronic component whose resistance value changes due to a temperature change. The inner space on the distal end side of the metal case portion 13 is filled with a heat conductive material (potting material) 18 made of an epoxy resin material, grease, or the like so as to surround the thermistor 17. The temperature sensor 53 is configured to be able to detect the temperature of the refrigerant flowing through the refrigerant passage from a change in the resistance value of the thermistor 17 by disposing at least the distal end portion thereof in the refrigerant passage. Further, a signal relating to a temperature change of the thermistor 17 is transmitted to the control board 3 via the female connector 16.

As shown in fig. 10, in the present example, a temperature sensor 53 is disposed in the vicinity of the power conversion circuit inside the power conversion device. However, since the conventional temperature sensor 53 includes the metal case 13 made of a conductive material such as brass, it is necessary to provide a predetermined distance between the members necessary for securing insulation from the conductive members constituting the power conversion circuit 1. Referring to fig. 10, when the temperature sensor 53 is currently disposed inside the power conversion device, a predetermined inter-component distance 19 necessary for ensuring insulation needs to be provided between the conductive member of the power conversion circuit 1 and the member disposed closest to the temperature sensor 53 (in this example, the strong electric element connection portion 20). As a result, if the temperature sensor 53 is disposed inside the power converter, there is a problem that the size of the power converter becomes large in accordance with the predetermined inter-component distance 19.

The above is a problem of the current power conversion device. As described above, according to the power conversion apparatus 100 according to the present invention, the above-described problem can be solved for the conventional power conversion apparatus. Hereinafter, the power conversion device 100 according to embodiment 1 of the present invention will be described in detail with reference to fig. 2 and the like.

Fig. 2 is a sectional view taken along line a-a of fig. 1, and is a diagram illustrating details of the temperature sensor 8 included in the power conversion device 100 according to embodiment 1.

As shown in the figure, the temperature sensor 8 is composed of a sensor housing portion 23 and a sub portion 29 housed therein. The sensor housing portion 23 includes the male connector portion 12, the body portion 11, and a projection 30 that is a portion projecting into the refrigerant passage 6. As shown in the drawing, the sensor housing portion 23 constituting the temperature sensor 8 of the present embodiment is formed integrally with the base member 5 made of resin.

Fig. 3 is a schematic configuration diagram illustrating an example of the configuration of the sub-section 29. The sub-portion 29 is configured to include the thermistor 17, the lead wire 24, the signal terminal 25, and the resin cover 28. The thermistor 17, the lead wire 24, and the signal terminal 25 are conductive members.

The thermistor 17 is an electronic component whose resistance value changes according to a temperature change. A signal relating to the resistance value of the thermistor 17 that changes in accordance with the temperature of the detection object is transmitted to the control board 3 via the lead wires 24, the signal terminals 25, and the female connector 16 described later. The resin cover 28 is configured to hold the signal terminal 25 electrically connected to the thermistor 17 and the lead wire 24, and to be held at a predetermined position inside the sensor housing portion 23.

The explanation is continued with returning to fig. 2. As described above, the temperature sensor 8 includes the sensor housing portion 23 and the sub portion 29. As shown in the drawing, the sensor housing portion 23 (male connector portion 12, main body portion 11, and protrusion portion 30) is integrally configured with the resin-made base member 5. That is, in the power converter 100 of the present embodiment, the conductive member related to the subsection 29 of the temperature sensor 8 is surrounded by the resin wall made of the insulating material. The resin wall is a part of the temperature sensor 8, and is configured as a sensor housing portion 23 that houses the sub portion 29.

The sensor housing portion 23 of the present embodiment is configured to include a cylindrical (cylindrical) portion formed to protrude from one surface of the base member 5 (the same surface as the surface on which the power module 2 is mounted in the present embodiment) in a space formed between the base member 5 and the metal cover 7 (see fig. 1). The male connector portion 12 is a cylindrical portion formed continuously with the main body portion 11, and is formed to be capable of fitting with the female connector 16. The projection 30 is a cylindrical portion formed so as to project into the refrigerant passage 6 formed in the base member 5, and forms a space therein. This space is formed continuously with the internal spaces of the male connector 12 and the main body 11 formed in a cylindrical shape.

The temperature sensor 8 is configured by mounting the sub-portion 29 in a space continuous with the inside of the male connector portion 12, the main body portion 11, and the projecting portion 30 constituting the sensor housing portion 23.

The subparts 29 are preferably mounted so that the thermistor 17 is located in the interior space of the projection 30 and the signal terminal 25 is located in the interior space of the male connector portion 12. As shown in the drawing, the subpart 29 of the present embodiment is mounted so that the thermistor 17 is positioned in the internal space of the projecting portion 30, a part of the signal terminal 25, a part of the resin cover 28, and the lead wire 24 are positioned in the internal space of the main body portion 11, and a part of the signal terminal 25 on the side connected to the female connector 16 and a part of the resin cover 28 are positioned in the internal space of the male connector portion 12. Thus, the temperature sensor 8 of the present embodiment is formed integrally with the base member 5, and the tip portion (the protruding portion 30) in which the thermistor 17 is housed is disposed in the refrigerant passage 6 through which the refrigerant as the temperature detection target flows, and the signal relating to the measured temperature can be transmitted to the control board 3 via the female connector 16 fitted to the male connector 12.

The boundary line of each of the male connector portion 12, the body portion 11, and the projecting portion 30 of the sensor housing portion 23 is not particularly limited. In the present embodiment, as an example, a portion of the sensor housing portion 23 on one end side and having a portion capable of being fitted to the female connector 16 is referred to as a male connector portion 12, a portion of the sensor housing portion 23 on the other end side and having a portion projecting toward the refrigerant passage 6 is referred to as a projection portion 30, and a portion of the sensor housing portion that is located between the male connector portion 12 and the projection portion 30 and that rises from the base member 5 at least on the same surface as the surface on which the power module 2 of the base member 5 is mounted is referred to as a body portion 11.

The heat conductive material 18 is filled in the internal space of the main body 11 and the protrusion 30, in other words, the space on the protrusion side (refrigerant flow path side) of the resin cover 28 in the temperature sensor 8. The heat conductive material 18 is a material (potting material) having heat conductivity such as an epoxy resin material or grease. Thus, in the thermistor 17, in a state where the projection 30 and the cooling water are in contact with each other in the cooling medium flow path 6, the heat of the cooling water is more easily transmitted through the heat conductive material 18, and therefore the temperature of the cooling medium can be more appropriately detected.

The shape of the projecting portion 30 may be set as appropriate in consideration of strength and the like. However, if it is assumed that the strength is satisfied, it is preferable to form the cooling water as thin as possible so that the temperature of the cooling water can be accurately transmitted through the thermistor 17. The protrusion 30 is preferably formed to allow the coolant in the coolant flow path 6 to flow more without resistance. For example, the projection 30 may be formed in an elliptical shape, and the major axis thereof may be aligned with the direction in which the cooling water flows.

With the above-described configuration, the temperature sensor 8 can detect the temperature of the cooling water flowing through the cooling medium flow path 6 in the power conversion device 100 without involving a risk of the cooling water flowing through the cooling medium flow path 6 entering the interior of the power conversion device 100 (the space between the base member 5 and the metal cover 7).

Further, since the conductive members including the thermistor 17, the signal terminal 25, and the like included in the temperature sensor 8 are surrounded by the sensor housing portion 23 made of resin of an insulating material, insulation between the temperature sensor 8 and the electronic components (particularly, the strong electric element connection portion 20 of the power module 2 in the drawing) disposed inside the power conversion device 100 can be ensured without providing the predetermined inter-component distance 19 (see fig. 10). As a result, the temperature sensor 8 can be disposed in the power conversion device 100 in the vicinity of the power conversion circuit 1 including the power module 2 and the like without requiring the inter-component distance 19 for ensuring insulation, and the degree of freedom of the internal layout of the power conversion device 100 can be improved and the power conversion device 100 can be downsized. Further, since the temperature sensor 8 can be disposed in the vicinity of the power conversion circuit 1 as the temperature control target, the accuracy of the temperature control for the power conversion circuit 1 performed based on the cooling water temperature detected by the temperature sensor 8 can be improved. Further, by disposing the temperature sensor 8 inside the power conversion device 100, the external weak current wiring 52 shown in fig. 9 is not required, and therefore, the signal pin of the weak current connector 51 can be reduced and the cost can be reduced.

The above is the details of the power conversion device 100 according to embodiment 1. A modification of the power conversion device 100 according to embodiment 1 will be described below.

(modification 1)

Fig. 4 is a diagram illustrating a modification 1 of the power conversion device 100. The power converter 100 described above includes the base member 5 having the refrigerant passage 6 as a base portion of the power converter 100, but the power converter 100 is not limited to such a configuration. The power conversion device 100 may be configured as in modification 1 shown in fig. 4.

In modification 1 shown in fig. 4, a metal plate 31 made of metal such as aluminum is disposed outside the base member 5. The metal plate 31 is assembled with the metal cover 7 to constitute a part of an outer package (housing) of the power conversion device 100 of modification 1. The method of assembling the metal plate 31 and the metal cover 7 will be described with reference to fig. 5.

Fig. 5 is a diagram illustrating an example of a method of assembling the metal plate 31 and the metal cover 7. The portion shown in fig. 5 corresponds to the two-dot chain line circle portion of fig. 4.

The metal plate 31 and the metal cover 7 of modification 1 are fixed by bolts 33. At this time, as shown in the drawing, the bolt 33 is inserted from the outside of the metal plate 31, and a metal ferrule (washer) portion 34 provided at an end portion of the base member 5 is inserted and screwed into the metal cover 7. Thus, the base member 5 is fixed between the metal plate 31 and the metal cover 7, and the power conversion circuit 1 such as the power module 2 mounted on the base member 5 is accommodated between the metal plate 31 and the metal cover 7. By configuring the power converter 100 in this manner, the power converter 100 can ensure EMC shielding performance against the power conversion circuit 1 housed inside by the metal case configured by the metal plate 31 and the metal cover 7. Further, by using a rubber material such as nitrile rubber (NBR) or Ethylene Propylene Diene Monomer (EPDM), or a liquid sealant (FIPG) as the sealing member 32 between the base member 5 and the metal cover 7, the case sealing performance of the power conversion device 100 can be ensured.

(modification 2)

Fig. 6 is a diagram illustrating modification 2 of power conversion device 100. In the above-described power conversion device 100, the base member 5 is disposed below the power conversion device 100 as a base portion, but the power conversion device 100 is not limited to such a configuration. The power conversion device 100 may be configured as a modification 2 shown in fig. 6.

That is, the direction (vertical and horizontal direction) in which the power conversion device 100 is mounted is not particularly limited, and the base member 5 may be disposed on the upper side as shown in fig. 6. In this way, when applied to an electric vehicle, for example, the power conversion device 100 can be freely arranged according to a desired layout of the electric vehicle.

As described above, the power conversion device 100 according to embodiment 1 includes: a power conversion circuit 1 that converts input power into dc power or ac power; a resin base member 5 on which the power conversion circuit 1 is mounted; a cover 7 (cover member) that houses the power conversion circuit 1 with the base member 5; a refrigerant passage 6 provided inside the base member 5 and through which a refrigerant for cooling the power conversion circuit 1 flows; and a temperature sensor 8 provided in the base member 5 and detecting a temperature of the refrigerant flowing through the refrigerant passage 6. The temperature sensor 8 has a conductive member including at least the thermistor 17, and at least a part of the conductive member is surrounded by a resin wall made of an insulating material. Accordingly, since the conductive member of the temperature sensor 8 is surrounded by the resin wall made of resin of the insulating material, insulation between the electronic component (particularly, the strong electric element connection portion 20 of the power module 2 in the above description) arranged inside the power conversion device 100 and the temperature sensor 8 can be ensured without providing the predetermined inter-component distance 19 (see fig. 10). As a result, the temperature sensor 8 can be disposed inside the power conversion device 100 without increasing the size of the power conversion device 100.

Further, according to the power conversion device 100 of embodiment 1, the resin wall is a part of the temperature sensor 8, and is configured as the sensor housing portion 23 (housing portion) that houses the conductive members (the signal terminal 25, the lead wire 24, and the thermistor 17), and the sensor housing portion 23 is formed integrally with the base member 5 made of resin. In this way, in the sensor housing portion 23 of the temperature sensor 8, particularly, the portion (the projection portion 30) projecting to the refrigerant flow path 6 is integrally configured with the base member 5, and therefore, the risk of the cooling water flowing through the refrigerant flow path 6 entering the inside of the power conversion device 100 can be eliminated. Further, since the conductive member of the temperature sensor 8 is reliably housed in the sensor housing portion 23 made of resin of an insulating material, it is possible to ensure insulation between the temperature sensor 8 and the electronic components disposed inside the power conversion device 100 without requiring the predetermined inter-component distance 19 (see fig. 10), and it is possible to bring the position of the temperature sensor 8 closer to the position of the power module 2.

In addition, according to the power conversion device 100 of embodiment 1, the sensor housing portion 23 has the protrusion 30 protruding into the refrigerant passage 6, and the thermistor 17 is housed in the protrusion 30. This makes it possible to make the distance between the thermistor 17 of the temperature sensor 8 and the cooling water flowing through the refrigerant passage 6 closer, and to increase the area of contact between the cooling water and the projection 30, thereby making it possible to detect the temperature of the cooling water with higher accuracy.

(embodiment 2)

A power converter 200 according to embodiment 2 will be described.

Fig. 7 is a diagram illustrating a configuration example of the power converter 200 according to embodiment 2, and is a schematic cross-sectional view of a portion corresponding to the cross-sectional view a-a in fig. 1 of the power converter 200. The power converter 200 of the present embodiment is characterized by the arrangement of the temperature sensor 8 inside the power converter 200. In the figure, arrows indicate the flow direction of the cooling water in the cooling medium flow path 6.

Here, in the cooling medium flow path 6 for cooling the power module 2 housed in the power converter 200, a heat flow due to heat of the power module 2 is generated with respect to the cooling water flowing at the position where the power module 2 is disposed. As shown in fig. 7, for example, in the present embodiment, the cooling medium flow path 6 at the position where the power module 2 is disposed is provided with the heat radiation fins 27 for the purpose of improving the efficiency of heat exchange between the power module 2 and the cooling water, and heat flow (see wavy arrows) using the power module 2 as a heat source is generated from the heat radiation fins 27.

Therefore, the temperature sensor 8 according to embodiment 2 is disposed on the upstream side of the position where the power module 2 is disposed in the refrigerant passage 6 through which the cooling water for cooling the power module 2 flows. Thus, the temperature sensor 8 can more accurately measure the temperature of the cooling water flowing through the cooling medium flow path 6 without being affected by the heat flow due to the power module 2, and therefore, the accuracy of the temperature control for the power conversion circuit 1, which is performed based on the temperature of the cooling water measured by the temperature sensor 8, can be improved.

As described above, according to the power converter 200 of embodiment 2, the temperature sensor 8 is disposed upstream of the position where the power conversion circuit 1 is disposed in the refrigerant passage 6 provided in the base member 5. This makes it possible to measure the temperature of the cooling water flowing through the refrigerant passage 6, that is, the temperature of the cooling water that is not affected by the heat flow due to the power module 2, and therefore, the temperature of the cooling water can be measured more accurately, and the accuracy of the temperature control for the power conversion circuit 1 performed based on the temperature of the cooling water measured by the temperature sensor 8 can be improved.

Embodiment 3

A power converter 300 according to embodiment 3 will be described.

Fig. 8 is a diagram illustrating a configuration example of a power converter 300 according to embodiment 3, and is a schematic cross-sectional view of a portion corresponding to the cross-sectional view a-a in fig. 1 of the power converter 200. The power converter 300 of the present embodiment is characterized in that a current temperature sensor 53 (see fig. 10) is used as a temperature sensor for measuring the temperature of the cooling water, and the power converter further includes a resin wall 22 surrounding at least a part of the temperature sensor 53.

Specifically, as shown in fig. 8, the temperature sensor 53 according to the present embodiment is disposed in the vicinity of the power module 2 on the same surface of the base member 5 as the surface on which the power module 2 is mounted. The temperature sensor 53 is configured such that the base member 5 penetrates and protrudes into the refrigerant flow path 6 at a portion (see fig. 11(b)) of the distal end of the metal housing portion 13 on the opposite side of the male connector portion 12, in which at least the thermistor 17 is housed.

In other words, the base member 5 of the present embodiment is configured to have a through-hole communicating with the refrigerant flow path 6 in the vicinity of the position where the power module 2 is placed, and when the temperature sensor 53 is placed on the base member 5, the tip of the metal case portion 13 of the temperature sensor 53 is configured to protrude into the refrigerant flow path 6 by passing through the through-hole. The temperature sensor 53 is fixed by screwing the tap portion 14 provided in the metal case portion 13 to a predetermined position of the base member 5 or the like.

When the temperature sensor 53 is fixed to the base member 5, the sealing performance is ensured by using the sealing material 15. The sealing material 15 is made of a rubber material such as Nitrile Butadiene Rubber (NBR) or Ethylene Propylene Diene Monomer (EPDM), or a copper gasket.

Around the temperature sensor 53 of the present embodiment, a resin wall 22 is provided that is integrally formed with (integrally formed with) the base member 5. The resin wall 22 is configured to surround at least the periphery of the metal case portion 13. The height of the resin wall 22 in the present embodiment is set to be at least higher than the height of a line (see a broken line in the present embodiment) connecting the highest position of the metal case 13 and the portion (in the present embodiment, the strong electric element connection portion 20 of the power module 2) closest to the metal case 13 among the electronic components included in the power conversion circuit 1.

In this way, in the power conversion device 300, at least the metal case portion 13 of the temperature sensor 53 is surrounded by the resin wall 22, and thus insulation between the temperature sensor 53 and the electronic components of the power conversion circuit 1 can be ensured without providing the predetermined inter-component distance 19 (see fig. 19). As a result, the temperature sensor 53 can be disposed in the vicinity of the power conversion circuit 1 including the power module 2 without requiring the inter-component distance 19 in the power conversion device 300, so that the accuracy of temperature control for the power conversion circuit 1, which is performed based on the cooling water temperature detected by the temperature sensor 53, can be improved, and the power conversion device 300 can be downsized compared to the conventional one. Further, by disposing the temperature sensor 53 inside the power conversion device 300, the signal pin of the weak current connector 53 can be reduced and the cost can be reduced without the need for the external weak current wiring 52 shown in fig. 9.

As described above, according to the power conversion device 300 of embodiment 3, the conductive member includes the metal case portion 13 that houses the thermistor 17, and the temperature sensor 53 is configured such that, in a state of being mounted on the base member 5, a part of the metal case portion 13 penetrates the base member 5 and protrudes into the refrigerant flow path 6. Thus, since the metal case 13 of the temperature sensor 53 is surrounded by the resin wall 22 made of resin of an insulating material, it is possible to ensure insulation between the temperature sensor 53 and the electronic components disposed inside the power converter 300 without providing the predetermined inter-component distance 19 (see fig. 10). As a result, the temperature sensor 53 can be disposed inside the power conversion device 300 without increasing the size of the power conversion device 300, and therefore the power conversion device 300 can be downsized compared to the conventional one.

While the embodiment and the modification of the present invention have been described above, the embodiment and the modification merely illustrate a part of the application example of the present invention, and the technical scope of the present invention is not limited to the specific configurations of the embodiment and the modification. The present invention is not limited to the above-described embodiments and modifications, and various modifications and applications can be made.

For example, the sensor housing portion 23 and the resin wall 22 described as being formed integrally with the base member 5 need not be formed integrally with the base member 5 without being joined (joined). The sensor housing portion 23, the resin wall 22, and the base member 5 may be joined by secondary adhesion or mechanical bonding after being molded separately.

The shape of the sensor housing portion 23 and the like is not limited to the shape shown in the drawings. The strength and the like may be appropriately changed in consideration of the above-described technical features.