Vehicle power supply device

Abstract

To provide a power supply device for a vehicle capable of cooling a power supply side connector and a cable by a simple cooling method.SOLUTION: A power supply device for a vehicle includes a housing installed on the ground in contact with the ground, a power-supply-side connector connectable to a power-receiving-side connector installed at the bottom of a vehicle, a robot arm having one end to which a power supply connector is attached and a base end supported by the housing, a cable that supplies power to the power supply side connector, a control unit that controls the robot arm such that the power-supply-side connector is connected to the power-receiving-side connector when power supply to the vehicle is started, and the connection between the power-supply-side connector and the power-receiving-side connector is released when power supply is terminated. When the temperature of at least one of the power-supply-side connector and the cable reaches or exceeds a first threshold value during power supply for power supply, the control unit controls the robot arm such that the connection is temporarily disconnected and the power-supply-side connector comes into contact with the housing.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a vehicle power supply device. [Background technology]

[0002] Patent Document 1 discloses a charging device for a vehicle battery. The battery is charged using an AC power source external to the vehicle. In order to prevent deterioration of the battery due to high temperatures, when the battery temperature reaches or exceeds a predetermined temperature while current is being applied (while power is being supplied to the vehicle), the charging device disconnects a contactor (relay) on the electric circuit to stop current application, while cooling the battery using a forced cooling device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-290535 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, it is conceivable to configure a vehicle power supply device so that power is supplied to the vehicle battery by connecting a power supply connector provided at the tip of a robot arm installed on the ground to a power receiving connector installed under the vehicle. In a power supply device configured in this way, the power supply connector and the cable connected thereto may become hot due to heat generated by current flow. If the temperature of at least one of the power supply connector and the cable becomes excessively high, it may become necessary to limit the current flow. The implementation of such a current flow limit leads to an increase in the time required for charging, i.e., the vehicle battery cannot be charged efficiently. Therefore, if it becomes possible to cool the power supply connector and the cable using a simple cooling method, it is beneficial because the current flow limit can be avoided or suppressed.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and has an object to provide a vehicle power supply device that is capable of cooling a power supply side connector and a cable using a simple cooling technique. [Means for solving the problem]

[0006] A vehicle power supply device according to the present disclosure is configured to supply power to a vehicle battery via a power receiving connector installed under the vehicle. The vehicle power supply device includes a housing, a power supply connector, a robot arm, a cable, and a control unit. The housing is installed on the ground in contact with the ground. The power supplying connector is connectable to the power receiving connector. The robot arm has one end to which the power supplying connector is attached and a base end supported by the housing. The cable supplies power to the power supplying connector. The control unit controls the robot arm so that the power supplying connector is connected to the power receiving connector when starting power supply to the vehicle, and controls the robot arm so that the power supplying connector and the power receiving connector are disconnected when ending power supply. The control unit controls the robot arm so that when the temperature of at least one of the power supply connector and the cable becomes equal to or higher than a first threshold value during power supply, the connection is temporarily released and the power supply connector comes into contact with the housing.

[0007] The control unit may control the robot arm to resume the connection when the temperature of at least one of the power supply connector and the cable becomes equal to or higher than a first threshold and then drops to below a second threshold that is lower than the first threshold. Effect of the Invention

[0008] According to the vehicle power supply device of the present disclosure, when the temperature of at least one of the power supply connector and the cable becomes equal to or higher than a first threshold during power supply, the power supply connector and the power receiving connector are disconnected, and the robot arm is controlled so that the power supply connector comes into contact with the housing. This allows the heat of the power supply connector and the cable to be actively released to the ground through the housing. This allows the power supply connector temperature and the cable temperature to be quickly reduced. In this way, according to the vehicle power supply device of the present disclosure, the power supply connector and the cable can be cooled by a simple cooling method. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an example of a configuration of a vehicle power supply device according to an embodiment; [Diagram 2] FIG. 1 is a diagram for explaining an overview of robot arm control according to an embodiment. [Diagram 3] 10 is a flowchart showing an example of a process flow regarding energization control including robot arm control according to the embodiment. [Figure 4] 1A is a time chart showing the operation of energization control according to a comparative example, and FIG. 1B is a time chart showing the operation of energization control according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present disclosure will be described with reference to the accompanying drawings. In the embodiments shown below, when the number, quantity, amount, range, etc. of each element is mentioned, the technical idea of ​​the present disclosure is not limited to the mentioned number unless otherwise specified or clearly specified in principle. Furthermore, the structures, steps, etc. described in the embodiments shown below are not necessarily essential to the technical idea of ​​the present disclosure unless otherwise specified or clearly specified in principle.

[0011] 1. Configuration of vehicle power supply device 1 is a diagram illustrating an example of a configuration of a vehicle power supply device 10 according to an embodiment. The vehicle power supply device (hereinafter also simply referred to as "power supply device") 10 is configured to supply power to a vehicle 1. The vehicle 1 is an electric vehicle such as a battery electric vehicle or a plug-in hybrid vehicle.

[0012] The vehicle 1 includes a battery 2. The battery 2 is, for example, a lithium ion battery. A power receiving connector 3 is installed in a lower portion 1a of the vehicle 1. The power receiving connector 3 includes a power receiving electrode 3a and a case 3b surrounding the power receiving electrode 3a. The battery 2 is charged by power supplied from a power supply device 10 via the power receiving connector 3.

[0013] On the other hand, the ground-side power supply device 10 includes a ground unit 12. The ground unit 12 includes a housing 14, a power supply connector 16, a robot arm 18, a cable 20, and a control unit 22. The housing 14 is installed on the ground in a state in contact with the ground 100. The housing 14 is typically placed in a parking space. The power supply connector 16 includes a power supply electrode 16a corresponding to the power receiving electrode 3a of the power receiving connector 3, and a case 16b surrounding the power supply electrode 16a. The power supply connector 16 can be connected to the power receiving connector 3 in a state in which the power supply electrode 16a is in contact with the power receiving electrode 3a.

[0014] The robot arm 18 has one end 18a to which the power supply connector 16 is attached, and a base end 18b supported by the housing 14. As an example, the robot arm 18 is rotatably supported by the housing 14 at the base end 18b. The robot arm 18 is driven by an actuator 24. The actuator 24 is, for example, an electric, hydraulic, or pneumatic type.

[0015] The cable 20 is a cable for supplying power to the power supply electrode 16a. The cable 20 may pass through the inside of the robot arm 18, or may be disposed outside the robot arm 18 along the robot arm 18.

[0016] The power supply device 10 includes, as an example, a power supply stand 26. In the power supply stand 26, a power supply circuit 28 is arranged together with the control unit 22. The other end of the cable 20 is connected to the power supply circuit 28. Power is supplied to the power supply circuit 28 from an AC power source 30. As an example, the power supply circuit 28 is configured to convert the AC voltage supplied from the AC power source 30 into a DC voltage, and to have a function of variably controlling an output current. More specifically, in accordance with a command from the control unit 22, the power supply circuit 28 controls the current supplied to the vehicle 1 via the power supply side electrode 16a.

[0017] The control unit 22 is configured to include an electronic control unit (ECU), for example. When starting power supply, the control unit 22 controls the robot arm 18 so that the power supply connector 16 is connected to the power receiving connector 3. On the other hand, when ending power supply, the control unit 22 controls the robot arm 18 so that the power supply connector 16 is disconnected from the power receiving connector 3. When power supply is stopped (when there is no request for power supply), the robot arm 18 is stored in the housing 14 as indicated by the dashed line in FIG. 1.

[0018] As described above, the power supply device 10 of the present embodiment is a contact-type power supply device. According to the power supply device 10, the connection between the power supply side connector 16 and the power receiving side connector 3 can be performed automatically (i.e., without human intervention) by the control of the robot arm 18 by the control unit 22.

[0019] A temperature sensor 32 is attached to the power-feeding connector 16 to detect a connector temperature T1, which is the temperature of the power-feeding connector 16. A temperature sensor 34 is attached to the robot arm 18, for example, to detect a cable temperature T2, which is the temperature of the cable 20.

[0020] 2. Power supply control using robot arm control 2A and 2B are diagrams for explaining an overview of the robot arm control according to the embodiment. Fig. 2A shows a state in which the power supply connector 16 is connected to the power receiving connector 3 and electricity is being supplied to the vehicle 1.

[0021] The power supply connector 16 and the cable 20 connected thereto may become hot due to heat generated by the current flow. When at least one of the temperature of the power supply connector 16 (connector temperature T1) and the temperature of the cable 20 (cable temperature T2) becomes equal to or higher than a predetermined upper temperature limit Tmax1 or Tmax2, it may become necessary to limit the current flow to the power supply device 10. Specifically, for example, as shown in FIG. 4(A) described later, it is necessary to temporarily stop the current flow or reduce the current (output current of the power supply circuit 28). Implementing such a current limit increases the time required for charging, that is, it makes it difficult to charge the battery 2 efficiently.

[0022] In view of the above-mentioned problems, the power supply device 10 (controller 22) of this embodiment controls the robot arm 18 as follows in order to avoid or suppress power supply restrictions during power supply to the vehicle 1. That is, the controller 22 controls the robot arm 18 so as to obtain the operating position shown in Fig. 2(B) when at least one of the connector temperature T1 and the cable temperature T2 becomes equal to or higher than the respective upper temperature limits Tmax1 or Tmax2 during power supply for power supply. Note that these upper temperature limits Tmax1 and Tmax2 correspond to an example of the "first threshold value" according to the present disclosure.

[0023] Specifically, when at least one of the connector temperature T1 and the cable temperature T2 becomes equal to or higher than the respective upper temperature limits Tmax1 or Tmax2 during power supply (i.e., before power supply is completed), the control unit 22 controls the robot arm 18 so that the connection between the power supply side connector 16 and the power receiving side connector 3 is temporarily released and the power supply side connector 16 comes into contact with the housing 14.

[0024] Because the housing 14 is in contact with the ground 100, there is no or almost no temperature rise in the housing 14 due to the passage of electricity. Therefore, by bringing the power supply connector 16 into contact with the housing 14, it is possible to cool the power supply connector 16 by utilizing the temperature difference between the power supply connector 16 and the housing 14. In addition, by dissipating heat from the cable 20 connected to the power supply connector 16 to the housing 14 via the power supply connector 16, it is possible to cool the cable 20 as well. In this way, by bringing the power supply connector 16 into contact with the housing 14, heat dissipation from the power supply connector 16 and the cable 20 can be actively carried out.

[0025] Furthermore, when at least one of the connector temperature T1 and the cable temperature T2 drops below the second threshold value TH1 or TH2 after reaching or exceeding the upper temperature limits Tmax1 or Tmax2, the control unit 22 controls the robot arm 18 to resume connection between the power supplying connector 16 and the power receiving connector 3. The second threshold values ​​TH1 and TH2 are set to be lower than the upper temperature limits Tmax1 and Tmax2, respectively.

[0026] In addition, the operating position of the robot arm 18 shown in Fig. 2(B) for active heat dissipation may also be selected when the power supply to the vehicle 1 is completed and the robot arm 18 is stored in the housing 14. Alternatively, the operating position of the robot arm 18 may be different between when the robot arm 18 is stored following the completion of power supply and when heat is being dissipated. That is, when the robot arm 18 is stored in the housing 14, it is in an operating position where the power supply side connector 16 is not in contact with the housing 14, and on the other hand, when heat is being dissipated, the robot arm 18 may be rotated more than when it was stored, and the operating position shown in Fig. 2(B) may be selected.

[0027] 3 is a flowchart showing an example of a process flow related to power supply control including robot arm control according to the embodiment. The process of this flowchart starts when a request for power supply to the vehicle 1 is issued.

[0028] 3, first, in step S100, the control unit 22 starts connecting the power supplying connector 16 to the power receiving connector 3. Specifically, before the start of power supply, the robot arm 18 is stored in the housing 14. Therefore, the control unit 22 starts an operation of lifting the robot arm 18 using the actuator 24 for the connection.

[0029] In step S102 following step S100, the control unit 22 determines whether or not the connection of the power supply side connector 16 is complete. As a result, if the connection is complete, the process proceeds to step S104. In step S104, the control unit 22 controls the power supply circuit 28 to start supplying current.

[0030] In step S106 following step S104, it is determined whether or not at least one of the connector temperature T1 and the cable temperature T2 is less than the respective upper temperature limits Tmax1 or Tmax2. The upper temperature limits Tmax1 and Tmax2 are temperature standards that are determined in advance based on at least one of the heat resistance of the components (the power supply connector 16 and the cable 20) and a predetermined standard. The upper temperature limits Tmax1 and Tmax2 may be the same value or may be different values.

[0031] Note that the connector temperature T1 and the cable temperature T2 to be determined in step S106 are not limited to one location each. That is, the temperatures at multiple locations of the power supply connector 16 may each be compared with the upper temperature limit Tmax1, and similarly, the temperatures at multiple locations of the cable 20 may each be compared with the upper temperature limit Tmax2.

[0032] If the determination result in step S106 is positive, the process proceeds to step S108. In step S108, the control unit 22 determines whether the SOC (State Of Charge) of the battery 2 of the vehicle 1 has reached SOCfull (fully charged state). The power supply device 10 is configured to be able to communicate with the vehicle 1, and the control unit 22 acquires the SOC from the vehicle 1.

[0033] When the SOC reaches SOCfull in step S108, that is, when power supply to the vehicle 1 is completed, the process proceeds to step S110. In step S110, the control unit 22 controls the power supply circuit 28 to stop the current supply, while controlling the robot arm 18 to disconnect the power supply connector 16 and store the power supply connector 16 in the housing 14. This ends the process of the control unit 22 associated with the current power supply request.

[0034] On the other hand, if the SOC has not reached the SOCfull in step S108, that is, if the power supply to the vehicle 1 has not been completed, the process returns to step S106, whereby the power supply continues.

[0035] If the determination result in step S106 is negative, that is, if at least one of the connector temperature T1 and the cable temperature T2 has reached the respective upper temperature limits Tmax1 or Tmax2, the process proceeds to step S112. In step S112, the control unit 22 controls the power supply circuit 28 to temporarily stop the flow of electricity, while controlling the robot arm 18 to disconnect the power supply connector 16 and bring the power supply connector 16 into contact with the housing 14.

[0036] In step S114 following step S112, it is determined whether both the connector temperature T1 and the cable temperature T2 are less than the respective threshold values ​​TH1 and TH2. The threshold values ​​TH1 and TH2 are lower than the upper temperature limits Tmax1 and Tmax2, respectively. The threshold values ​​TH1 and TH2 may be the same value or may be different values. The threshold values ​​TH1 and TH2 correspond to an example of a "second threshold value" according to the present disclosure.

[0037] If the determination result in step S114 is negative, the control unit 22 repeatedly executes the process of step S114, whereby the power supply connector 16 is disconnected and the state in which the power supply connector 16 is in contact with the housing 14 is maintained.

[0038] On the other hand, if the determination result in step S114 is positive, that is, if both the power supplying connector 16 and the cable 20 have been cooled to below their respective thresholds TH1 or TH2, the process proceeds to step S116. In step S116, the control unit 22 controls the robot arm 18 to resume the connection of the power supplying connector 16 to the power receiving connector 3. Note that in step S114, the condition for starting the reconnection is that both the power supplying connector 16 and the cable 20 are below their respective thresholds TH1 or TH2. However, instead of this example, in step S114, it may be determined that the connector temperature T1 or the cable temperature T2 that reached the upper temperature limit Tmax in step S106 has only fallen to below the corresponding threshold TH1 or TH2.

[0039] In step S118 following step S116, the control unit 22 determines whether or not the connection of the power supply side connector 16 is complete. As a result, if the connection is complete, the process proceeds to step S120. In step S120, the control unit 22 controls the power supply circuit 28 to resume power supply.

[0040] 3.Effects The effects of the vehicle power supply device 10 of the present embodiment described above will be described with reference to a comparative example. This comparative example has the same hardware configuration as the power supply device 10, but differs from the present embodiment in the measures taken when at least one of the connector temperature T1 and the cable temperature T2 exceeds the respective upper temperature limits Tmax1 or Tmax2.

[0041] Fig. 4(A) is a time chart showing the operation of the current supply control according to the comparative example, and Fig. 4(B) is a time chart showing the operation of the current supply control according to the embodiment. More specifically, Fig. 4(A) and Fig. 4(B) show the operation during current supply for supplying power to the vehicle 1. In addition, the explanation of Fig. 4(A) and Fig. 4(B) will be given by taking the connector temperature T1 as an example out of the connector temperature T1 and the cable temperature T2, but the same applies to the cable temperature T2.

[0042] First, a comparative example will be described. Time point t1 in Fig. 4(A) corresponds to the time point when the connector temperature T1 reaches the upper temperature limit Tmax1 during current flow. In the comparative example, when time point t1 arrives, current flow restriction is executed. Specifically, the power supply circuit 28 is controlled so that current flow (power supply to the vehicle 1) is stopped or the current flowing from the power supply device 10 to the vehicle 1 is suppressed.

[0043] According to the comparative example, when the connector temperature T1 reaches the upper temperature limit Tmax1, it is necessary to wait until the connector temperature T1 drops due to the current flow restriction while keeping the power supply connector 16 connected. With this method, the time during which the current flow is restricted becomes longer, making it difficult to charge efficiently.

[0044] More specifically, in the power supply device 10 that supplies power from the ground, it is difficult to actively utilize natural cooling. The reason is that, first, power is supplied to the vehicle 1 while the vehicle is stopped. Another reason is that the components of the power supply device 10, such as the robot arm 18, are installed between the ground 100 and the underside of the vehicle 1, which causes poor ventilation. Since it is difficult to actively utilize natural cooling, the method of simply limiting the flow of current as in the comparative example extends the time during which the flow of current is restricted. In addition, even if the power supply is stopped in the comparative example with the power supply connector 16 disconnected, there is no significant difference in the time during which the flow of current is restricted unless there is active heat dissipation (see FIG. 2(B)) as in the present embodiment. Furthermore, it is also possible to add a cooling device for forcibly cooling the power supply connector 16 and the cable 20. However, adding a cooling device leads to an increase in the size of the device.

[0045] On the other hand, according to this embodiment, when time t1 arrives, the power supply connector 16 is disconnected, and the robot arm 18 is controlled so that the power supply connector 16 comes into contact with the housing 14 (see step S112). This allows the heat of the power supply connector 16 and the cable 20 to be actively released to the ground 100 via the housing 14. Therefore, as shown in FIG. 4(B), the connector temperature T1 can be quickly reduced. In this way, according to the robot arm control of this embodiment, the power supply connector 16 and the cable 20 can be cooled by a simple cooling method, so that the time during which the power supply is restricted can be effectively shortened. As a result, the battery 2 can be efficiently charged by using the power supply device 10 that supplies power from the lower side of the vehicle 1.

[0046] Furthermore, according to this embodiment, when the connector temperature T1 falls to below a second threshold TH1 lower than the upper temperature limit Tmax1 at time t2 after the connector temperature T1 becomes equal to or higher than the upper temperature limit Tmax1 (first threshold), the robot arm 18 is controlled to resume connection of the power supply connector 16. This makes it possible to resume power supply after lowering the connector temperature T1 to a desired value (second threshold TH1). [Explanation of symbols]

[0047] 1 vehicle 2 Battery 3. Power receiving connector 3a Receiving electrode 10 Vehicle power supply device 12 Ground Units 14. Chassis 16 Power supply connector 16a Power supply electrode 18 Robot Arm 20 Cable 22 Control section 24 Actuator 26 Power Supply Stand 28 Power supply circuit 30 AC power supply 32, 34 Temperature sensor 100 ground

Claims

1. A vehicle power supply device that supplies power to a battery of a vehicle via a power receiving connector installed under a vehicle, a housing installed on the ground in contact with the ground; a power supplying connector connectable to the power receiving connector; a robot arm having one end to which the power supply connector is attached and a base end supported by the housing; a cable for supplying power to the power supply connector; a control unit that controls the robot arm so that the power supplying side connector is connected to the power receiving side connector when starting power supply to the vehicle, and controls the robot arm so that the power supplying side connector and the power receiving side connector are disconnected when ending the power supply; Equipped with the robot arm is stored in the housing at a first operating position in which the power supply connector is not in contact with the housing when there is no request for power supply; When a temperature of at least one of the power supplying connector and the cable becomes equal to or higher than a first threshold value during energization for the power supply, the control unit controls the robot arm to rotate more greatly than the first operating position so as to obtain a second operating position in which the power supplying connector contacts the housing, while temporarily releasing the connection. A vehicle power supply device comprising:

2. The control unit controls the robot arm so that the connection is resumed when a temperature of at least one of the power supply connector and the cable becomes equal to or higher than the first threshold and then falls to less than a second threshold that is lower than the first threshold.

2. The vehicle power supply device according to claim 1.

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