JP2018122825A - On-vehicle structure of power control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for preventing damage to a fixed portion of a protector and protecting a connector from a cowl panel. An electric power control unit (PCU5) is fixed on a transaxle 30 accommodating a traveling motor 8 in a front compartment 90. A connector 23 is provided behind the upper surface of the housing 50 of the PCU 5. The cowl panel 44 is located behind the connector 23. The protector 61 is located on the side of the connector 23 and its rear end is located between the connector 23 and the cowl panel 40 in the vehicle front-rear direction. The protector 61 is fixed to the side surface 50b of the housing 50, and is provided with a contact surface 65a facing the housing with a predetermined gap behind and above the fixed portion. Even if the vehicle collides and the PCU 5 retracts and the protector 61 interferes with the cowl panel 44, the rotation of the protector 61 is suppressed by the contact surface 65a, and the load acting on the fixed portion is reduced. [Selection diagram] Fig. 4

Description

  This specification discloses the vehicle-mounted structure of the electric power control unit which controls the electric power supplied to the motor for driving | running | working.

  Many electric vehicles equipped with a traveling motor have a traveling motor and a power control unit for controlling the power supplied to the traveling motor mounted in the front space of the vehicle. In order to reduce the transfer loss of the power supplied to the traveling motor, the power control unit is fixed on a housing that houses the traveling motor (for example, Patent Document 1). The power control unit disclosed in Patent Document 1 is provided with a connector at the rear of the upper surface of the housing.

Japanese Patent Laying-Open No. 2015-133803

  There is a possibility that the power control unit mounted in the front space of the vehicle is retracted by an impact when the vehicle collides forward. When the power control unit moves backward, it interferes with the cowl panel located behind the power control unit, and the connector on the rear upper surface of the casing of the power control unit may be damaged. On the other hand, the power control unit includes a discharge circuit that discharges a high-voltage capacitor in the event of a collision, and receives a discharge command from the outside through the connector to discharge the capacitor. If the connector is damaged during a collision, the discharge command may not reach the discharge circuit and the capacitor may not be discharged.

  In order to protect the connector from the cowl panel, the inventor considered providing a protector between the connector and the cowl panel in the vehicle front-rear direction. Even when the power control unit retreats due to an impact during a frontal collision of the vehicle, the rear end of the protector interferes with the cowl panel, so that the power control unit stops retreating, and the connector can be protected from the cowl panel.

  When the rear end of the protector interferes with the cowl panel due to a frontal collision of the vehicle, the protector rotates about the fixed portion. This rotation causes a load to act on the fixed location. In particular, when there are various circumstances where the protector cannot be fixed to the rear surface of the casing of the power control unit (for example, other members (cables, etc.) are disposed in the vicinity of the rear surface). Is fixed to the side of the housing facing in the vehicle width direction. In this case, the distance between the fixed location of the protector and the rear end of the protector becomes long, and the load acting on the fixed location due to the rotation of the protector increases. If the fixing portion of the protector is damaged by this load, the power control unit does not stop moving backward and the connector may interfere with the cowl panel. The present specification discloses a technique for protecting a connector from a cowl panel by preventing breakage of a fixing portion of a protector.

  In the in-vehicle structure disclosed in this specification, as described above, the protector is fixed to the casing of the power control unit. The protector is located on each side of the connector, and its rear end is located between the connector and the cowl panel in the vehicle front-rear direction. Each protector is fixed to a side surface of the casing facing in the vehicle width direction, and includes a contact surface facing the casing with a predetermined gap behind the fixed portion.

  According to this vehicle-mounted structure, due to a frontal collision of the vehicle, when the protector rotates toward the front of the vehicle around the fixed part, the contact surface located at the upper rear side of the fixed part comes into contact with the casing. Thereby, rotation of a protector is suppressed by a contact surface. Since the rotation of the protector is suppressed by the contact surface, the load acting on the fixed portion is reduced as compared with the configuration without the contact surface. The connector can be protected from the cowl panel by preventing breakage of the protector fixing portion. Details and further improvements of the technology disclosed in this specification will be described in the following “DETAILED DESCRIPTION”.

It is a block diagram of the electric power system of the hybrid vehicle containing the vehicle-mounted structure of an Example. It is a perspective view which shows the device arrangement | positioning in the front compartment of the hybrid vehicle containing the vehicle-mounted structure of an Example. It is a top view of PCU (power control unit) mounted on the vehicle. It is a side view of PCU mounted on the vehicle. It is sectional drawing in the VV line.

  An in-vehicle structure of an embodiment will be described with reference to the drawings. The in-vehicle structure of the embodiment is employed in a hybrid vehicle 100 including a traveling motor and an engine. First, the electrical system of the hybrid vehicle 100 will be described. FIG. 1 shows a block diagram of the electric system of hybrid vehicle 100. It should be noted that some parts of the block diagram of FIG. 1 that are not necessary for the description of the technology disclosed herein are omitted.

  The hybrid vehicle 100 includes a traveling motor 8 (hereinafter referred to as “motor 8”) and an engine 13. The output of the motor 8 and the output of the engine 13 are combined by the power distribution mechanism 9 and output to the axle 11. The power distribution mechanism 9 distributes the output torque of the engine 13 to the axle 11 and the motor 8 in some cases. At this time, the motor 8 generates power using a part of the output torque of the engine 13. Alternatively, the motor 8 generates power using deceleration energy of the vehicle. The electric power obtained by power generation is used for charging the high voltage battery 3 via the power control unit 5. An engine controller 12 is provided in the casing of the engine 13. The engine controller 12 is connected to the HV controller 6 that controls the entire vehicle by an engine wire harness 28. The engine wire harness 28 is a communication cable for transmitting various signals between the HV controller 6 and the engine controller 12.

  The motor 8 is driven by AC power supplied from the power control unit 5. The power control unit 5 converts the DC power of the high voltage battery 3 into AC power suitable for driving the motor 8 and supplies it to the motor 8. The output of the high voltage battery 3 is, for example, 300 volts. Hereinafter, for convenience of explanation, “power control unit 5” is referred to as “PCU5 (Power Control Unit 5)”.

  The PCU 5 includes a voltage converter circuit and an inverter circuit. The voltage converter circuit boosts the power of the high voltage battery 3 to a voltage suitable for driving the motor 8. The boosted voltage is, for example, 600 volts. The inverter circuit converts the boosted DC power into three-phase AC power having a frequency suitable for driving the motor 8. The inverter circuit also has a function of converting AC power generated by the motor 8 into DC power. The voltage converter circuit also has a function of stepping down the voltage of the electric power converted by the inverter circuit to the voltage of the high voltage battery 3. That is, the voltage converter circuit built in the PCU 5 is a bidirectional DC-DC converter. Detailed description of the voltage converter circuit and the inverter circuit will be omitted.

  The PCU 5 is provided with a capacitor 16 that smoothes the current of the high-voltage battery 3. Furthermore, the PCU 5 is provided with a discharge circuit 17 that discharges the capacitor 16 in the event of a vehicle collision. The discharge circuit 17 is, for example, a discharge resistor. Alternatively, the boost converter circuit or inverter circuit described above may be used as a discharge circuit.

  The voltage of the high-voltage battery 3 is applied to the capacitor 16, and the safety of the PCU 5 is ensured by the discharge circuit 17 discharging the capacitor 16 in the event of a collision. A discharge command for starting the discharge circuit 17 and discharging the capacitor 16 is transmitted from the HV controller 6 to the PCU 5. When the HV controller 6 receives a signal indicating that the vehicle has collided from the airbag controller 18, the HV controller 6 transmits a discharge command to the PCU 5. At the same time, the HV controller 6 opens the system main relay 4 that electrically connects the high voltage battery 3 and the PCU 5. When the system main relay 4 is opened, the PCU 5 is disconnected from the high voltage battery 3, power supply to the capacitor 16 is stopped, and the capacitor 16 can be discharged. The airbag controller 18 includes an acceleration sensor that detects a collision. When the acceleration sensor detects an acceleration that is equal to or greater than a predetermined magnitude, the airbag controller 18 transmits a signal indicating that the vehicle has collided to the HV controller 6.

  The high voltage battery 3 and the PCU 5 are connected by a high voltage power line 24. One end of the high voltage power line 24 is connected to a high voltage connector 21 provided in the PCU 5. That is, the high voltage power line 24 and the high voltage connector 21 supply the power of the high voltage battery 3 to the PCU 5. The system main relay 4 is inserted into the high voltage power line 24.

  The PCU 5 also accommodates a control circuit that is driven at a low voltage. Here, the low voltage is a voltage lower than the output voltage of the high voltage battery 3 described above. The PCU 5 is also connected to the auxiliary battery 7 in order to supply power to the control circuit. The output voltage of the auxiliary battery 7 is lower than the output voltage of the high voltage battery 3 and is, for example, 12 volts. The PCU 5 and the auxiliary battery 7 are connected to the PCU 5 through the auxiliary common power line 14 and the low voltage power line 26. One end of the low voltage power line 26 is connected to a low voltage connector 23 provided in the PCU 5. The auxiliary common power line 14 is a power line that extends around the vehicle and supplies electric power to various auxiliary machines. “Auxiliary equipment” is a generic term for a group of devices driven at a low voltage. An example of the auxiliary machine is a car navigation device 15. A control circuit that is mounted on the PCU 5 and operates at a low voltage also belongs to the “auxiliary machine”.

  In addition to the low voltage power line 26, a PCU wire harness 27 is connected to the low voltage connector 23. The PCU wire harness 27 is a communication cable for exchanging various signals between the PCU 5 and the HV controller 6. The discharge command described above is also transmitted from the HV controller 6 to the PCU 5 through the PCU wire harness 27. If the low-voltage connector 23 is damaged before the HV controller 6 sends a discharge command to the PCU 5 when the vehicle collides, the PCU 5 cannot properly receive the discharge command and the capacitor 16 may not be discharged. . The hybrid vehicle 100 has a structure in which the low voltage connector 23 is not easily damaged during a frontal collision. Next, the in-vehicle structure 2 of the PCU 5 will be described.

  The in-vehicle structure 2 of the PCU 5 will be described with reference to FIGS. FIG. 2 is a perspective view showing a device layout in the front compartment 90 of the hybrid vehicle 100. FIG. 3 is a plan view of the PCU 5 mounted in the front compartment 90. FIG. 4 is a side view of the PCU 5 mounted in the front compartment 90. 3 shows only the PCU 5 and its periphery. Reference numeral 43 in FIG. 4 denotes a hood that covers the front compartment 90. 2 and 3, the hood 43 is not shown.

  The coordinate system in the figure will be described. The F axis of the coordinate system indicates the front of the vehicle, the H axis indicates the vehicle width direction, and the V axis indicates the upper side of the vehicle. Hereinafter, “front” in this specification means “front” in the vehicle longitudinal direction, and “rear” means “rear” in the vehicle longitudinal direction. The front compartment 90 corresponds to the front space of the vehicle.

  The front compartment 90 stores the engine 13, the transaxle 30 (motor 8), the PCU 5, and the auxiliary battery 7. Note that various other parts are stored in the front compartment 90, but description thereof will be omitted here except for the parts described above. The transaxle 30 houses a traveling motor 8, a power distribution mechanism 9, and a differential gear. That is, the transaxle 30 is also a housing that accommodates the traveling motor 8. The transaxle 30 is connected to the engine 13 in the vehicle width direction. The output torque of the engine 13 and the output torque of the motor 8 are combined by the power distribution mechanism 9 in the transaxle 30 and transmitted to the axle 11 via the differential gear.

  The PCU 5 is fixed to the transaxle 30. More specifically, the housing 50 of the PCU 5 is fixed above the transaxle 30 by a front bracket 31 and a rear bracket 32 (not shown in FIG. 2). As shown in FIG. 4, a gap is secured between the upper surface of the transaxle 30 and the PCU 5 (ie, the casing 50). That is, the PCU 5 does not directly touch the transaxle 30 but is supported by the transaxle 30 via the front bracket 31 and the rear bracket 32. This is to protect the PCU 5 from vibrations of the engine 13 and the motor 8. Although illustration is omitted, anti-vibration bushes are incorporated between the front bracket 31 and the PCU 5 and between the rear bracket 32 and the PCU 5. Since the PCU 5 is supported by the front bracket 31 and the rear bracket 32, the PCU 5 may retreat when receiving a collision load from the front during a vehicle collision.

  A low voltage connector 23 is provided behind the upper surface of the housing 50 of the PCU 5. The low voltage connector 23 is a connector for connecting the low voltage power line 26 connected to the auxiliary battery 7 and the PCU wire harness 27 connected to the HV controller 6 to the PCU 5.

  As shown in FIG. 4, a high voltage connector 21 is provided on the rear surface 50 a of the casing 50 of the PCU 5. The high voltage connector 21 is a connector for connecting the high voltage power line 24 connected to the high voltage battery 3 shown in FIG. In FIG. 3, the high voltage connector 21 and the high voltage power line 24 are not shown.

  A metal cowl panel 44 is disposed on the vehicle rear side of the front compartment 90. The cowl panel 44 is connected to a front compartment 90 and a dash panel 48 (see FIG. 4, not shown in FIGS. 2 and 3) that partitions the passenger compartment. The cowl panel 44 extends in the vehicle width direction and, as shown in FIG. 4, is a plane that extends in the vehicle front-rear direction (F-axis direction in the drawing) and the vehicle vertical direction (V-axis direction in the drawing). The cut section has a curved shape that opens upward. In other words, the “curved shape opened upward” means that the curved shape is convex downward. The rear edge of the cowl panel 44 is in contact with the lower edge of the windshield 46, and the front edge is in contact with the hood 43 that covers the front compartment 90.

  The upper part of the cowl panel 44 is covered with a resin cowl top panel 45. Further, a wiper pivot 34 is disposed inside the open curved shape on the cowl panel 44. The wiper pivot 34 is supported by a pivot holder 49. The pivot holder 49 is fixed to the cowl panel 44. The wiper pivot 34 passes through the cowl top panel 45 and a part thereof is exposed. The wiper pivot 34 is a component that serves as a rotation axis of the wiper arm 36 (see FIG. 2). 3, illustration of the wiper pivot 34 and the wiper arm 36 is omitted, and illustration of the wiper arm 36 is omitted in FIG.

  As shown in FIG. 4, a cowl panel 44 is located behind the low voltage connector 23. If the PCU 5 moves backward due to the impact of the frontal collision, the low voltage connector 23 may come into contact with the metal cowl panel 44. If the low voltage connector 23 is damaged due to contact with the cowl panel 44, the discharge command sent from the HV controller 6 through the PCU wire harness 27 may not be transmitted to the discharge circuit 17 inside the PCU 5.

  Therefore, the PCU 5 includes protectors 60 and 61 on each side of the low voltage connector 23 (that is, both sides in the vehicle width direction of the low voltage connector) in order to suppress damage to the low voltage connector 23 when the PCU 5 is retracted. . As described above, the high voltage connector 21 is provided on the rear surface 50 a of the housing 50. Due to the presence of the high voltage connector 21, it is difficult to secure a space for fixing protectors 60 and 61 described later on the rear surface 50 a. For this reason, the protectors 60 and 61 are fixed to the side surface of the housing 50 facing the vehicle width direction.

  The protector 60 has a symmetrical shape with respect to the protector 61 in a plane extending in the vehicle front-rear direction and the vehicle vertical direction. Moreover, the both sides | surfaces of the housing | casing 50 of PCU5 which face a vehicle width direction (namely, H-axis direction) oppose the contact part of the protectors 60 and 61 (the part of the code | symbol 65 in the protector 61, code | symbol abbreviate | omitted in the protector 60). Abutting protrusions 51 and 52 are provided. Hereinafter, the description of the protector 61 will be continued. It should be noted that in FIG. 2, the shapes of the contact portions of the protectors 60 and 61 are omitted.

  The protector 61 is made by casting iron, aluminum alloy or the like. The protector 61 includes an interference part 62, a fixing part 63, a first contact part 65, and a second contact part 66. The interference part 62 is a part for protecting the low voltage connector 23 from the cowl panel 44 by interfering with the cowl panel 44 at the time of a forward collision. The interference part 62 is a plate-like part and is located at the rear end of the protector 61. The interference part 62 is inserted between the low voltage connector 23 and the cowl panel 44 so that the plate-shaped surface thereof faces the vehicle front-rear direction.

  The fixing part 63 is a part for fixing the protector 61 to the side surface 50b of the housing 50 facing the vehicle width direction. The fixing portion 63 extends from the lower end of the interference portion 62 toward the front of the vehicle along the side surface 50b across the rear surface 50a. A through hole (not shown) penetrating in the vertical direction is provided at an end portion of the fixed portion 63 in the front of the vehicle. The end portion is fastened to a fixing protrusion 54 provided on the side surface 50b of the housing 50 by a bolt 64 passing through the through hole.

  The first abutment portion 65 extends from the plate-shaped surface of the interference portion 62 toward the front of the vehicle along the side surface 50b across the rear surface 50a. The first abutting portion 65 is located above the fixed portion 63. An end portion of the first abutting portion 65 in the front of the vehicle is located on the rear upper side of the bolt 64. The end portion faces the contact protrusion 52 provided on the side surface 50 b of the housing 50.

  The second abutting portion 66 extends from the plate-shaped surface of the interference portion 62 toward the front of the vehicle in parallel with the first abutting portion 65 without traversing the rear surface 50a. The second abutting portion 66 faces the rear surface 50 a of the housing 50. The second contact portion 66 is located closer to the low voltage connector 23 than the first contact portion 65 in the vehicle width direction (that is, the H-axis direction).

  With reference to FIG. 5, the 1st contact part 65 and the 2nd contact part 66 are further demonstrated. 5 is a cross-sectional view taken along line VV in FIG. The contact protrusion 52 is positioned in front of the first abutment portion 65 in the vehicle. The contact surface 65a located at the vehicle front end of the first contact portion 65 faces the contact protrusion 52 with a gap G1 therebetween. Further, the contact surface 66a located at the vehicle front end of the second contact portion 66 faces the rear surface 50a of the housing 50 with a gap G2 therebetween. The gaps G <b> 1 and G <b> 2 are designed such that the forward rotation of the protector 61 centering on the fixed portion by the bolt 64 stops at a predetermined angle.

  In addition, the contact surfaces 65 a and 66 a are located between the place where the bolt 64 is fixed and the rear end of the interference portion 62. In other words, the contact surfaces 65 a and 66 a are located above the fixing portion of the protector 61.

  The effect of the present embodiment will be described. When the PCU 5 moves backward due to a frontal collision of the hybrid vehicle 100, the rear end of the protector 61 (that is, the interference unit 62) interferes with the cowl panel 44. At this time, the protector 61 rotates toward the front of the vehicle around a fixed portion by the bolt 64. When the protector 61 rotates, the gap G1 and the gap G2 are narrowed. The contact surface 65a contacts the contact protrusion 52, and the contact surface 66a contacts the rear surface 50a. Thereby, rotation centering on the fixed location of the protector 61 is suppressed by the contact surfaces 65a and 66a. In the configuration that does not include the first contact portion 65 and the second contact portion 66, the rotation of the protector 61 cannot be suppressed, and a large tensile load acts on the bolt 64. On the other hand, in the present embodiment, since the rotation of the protector 61 is suppressed by the contact surfaces 65a and 66a, the tensile load acting on the bolt 64 can be reduced. As a result, it is possible to protect the low voltage connector 23 from the cowl panel 44 by preventing breakage of the fixing portion of the protector 61 (that is, the bolt 64).

  In the present embodiment, the first abutment portion 65 and the contact protrusion face each other in the vehicle front-rear direction. For this reason, the contact surface 65a can also suppress the movement of the protector 61 forward of the vehicle. For example, a configuration in which the contact protrusion is located above the first contact portion 65 and the upper surface of the first contact portion 65 faces the contact protrusion is also conceivable. With this configuration, the rotation of the protector 61 can be suppressed, but the movement of the protector 61 forward of the vehicle cannot be suppressed. On the other hand, in this embodiment, not only the rotation of the protector 61 but also the movement of the protector 61 forward of the vehicle can be suppressed. Not only the tensile load acting on the bolt 64 but also the shear load can be reduced.

  In the present embodiment, the contact surfaces 65 a and 66 a are located on the rear upper side of the place where the bolt 64 is fixed. For example, the first abutting portion extends across the bolt 64 and extends to the front of the bolt 64, and includes a contacting surface that faces the abutting protrusion with a predetermined gap at the front lower side of the bolt 64. Conceivable. In this configuration, when the protector 61 rotates around the fixed portion, the contact surface comes into contact with the contact protrusion. Thereby, rotation centering on a fixed location is suppressed. However, after the contact surface comes into contact with the contact protrusion, the center of rotation of the protector 61 can change from a fixed location to a contact location between the contact surface and the contact projection. The rotation around the contact portion cannot be suppressed, and a tensile load can act on the bolt 64. On the other hand, in the present embodiment, even if the center of rotation of the protector 61 changes from the fixed location to the contact location between the contact surface 65a and the contact projection 52, the rotation of the protector 61 is suppressed by the fixed projection 54. Thereby, the tensile load which acts on the volt | bolt 64 can be reduced.

  Points to be noted regarding the technology described in the embodiments will be described. The front compartment 90 corresponds to a “front space” in the claims. The transaxle 30 corresponds to an example of a housing of the claims. The vehicle-mounted structure disclosed in this specification can also be applied to an electric vehicle that does not include an engine. In this case, the motor housing that houses the traveling motor corresponds to the “housing” in the claims.

  Moreover, the protector 61 should just be provided with either one of the 1st contact part 65 and the 2nd contact part 66. FIG. Further, the protector 60 may not have a plane-symmetric shape with respect to the protector 61. The protector 60 may have a shape different from the plane-symmetric shape.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: In-vehicle structure 3: High voltage battery 4: System main relay 5: Power control unit 6: HV controller 7: Auxiliary battery 8: Motor 9: Power distribution mechanism 11: Axle 12: Engine controller 13: Engine 16: Capacitor 17 : Discharge circuit 18: Airbag controller 21: High voltage connector 23: Low voltage connector 24: High voltage power line 26: Low voltage power line 27: PCU wire harness 30: Transaxle 31: Front bracket 32: Rear bracket 34: Wiper pivot 44 : Cowl panel 50: housings 51 and 52: contact protrusions 60 and 61: protector 62: interference part 63: fixing part 64: bolt 65: first contact part 65a: contact surface 66: second contact part 66a: contact surface 90: Front compartment 100: High Lid cars

Claims (1)

It is a vehicle-mounted structure of a power control unit that controls the power supplied to the traveling motor,
The power control unit is fixed on a housing that houses the traveling motor in a front space of the vehicle,
A connector is provided at the rear of the upper surface of the casing of the power control unit,
A cowl panel is located behind the connector,
A protector positioned between the connector and the cowl panel in the vehicle front-rear direction and positioned at each side of the connector is fixed to the housing.
Each protector is fixed to a side surface of the casing facing in the vehicle width direction, and includes a contact surface facing the casing with a predetermined gap above and behind the fixing portion.
In-vehicle structure of power control unit.

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