Vehicle power supply system

Abstract

To further reliably prevent a worker, who starts work with respect to a battery pack, from touching a component, to which a high voltage is being applied, around the battery pack.SOLUTION: A vehicle power supply system is applied to a vehicle including a cover member which covers a battery pack and is opened by a worker when working with respect to the battery pack, and comprises a high voltage battery, a relay, an interlock device, and an electronic control unit. The high voltage battery is included in the battery pack and supplies power to a high voltage apparatus. The relay is included in the battery pack and switches electrical connection / disconnection between the high voltage battery and the high voltage apparatus. The interlock device includes a switch in which a change of a contact state occurs while being interlocked with the opening of the cover member, and outputs an interlock signal indicating that the opening is performed in response to the change of the contact state. The electronic control unit controls the relay so as to perform the electrical disconnection in response to reception of the interlock signal.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a vehicle power supply system.

Background Art

[0002] Patent Document 1 discloses a power supply device for an electric vehicle. To prevent an operator from accidentally disconnecting a high-voltage connector, this power supply device has a structure in which, even if the operator attempts to disconnect the high-voltage connector while the interlock connector is not removed, the interlock member covers the unlock button of the high-voltage connector and makes the operation impossible.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the power supply device described in Patent Document 1, the interlock connector is arranged near the high-voltage connector. There are high-voltage components such as terminal parts or wiring around the high-voltage connector. Therefore, according to the above power supply device, when an operator performs an operation of removing the interlock connector, there is a possibility of accidentally touching the surrounding components to which a high voltage is applied.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a vehicle power supply system that can more reliably prevent an operator who starts working on a battery pack from touching components to which a high voltage is applied around the battery pack.

Means for Solving the Problems

[0006] The vehicle power supply system according to the present disclosure is applied to a vehicle including a cover member that shields a battery pack and is opened by an operator when working on the battery pack. The vehicle power supply system includes a high-voltage battery, a relay, an interlock device, and an electronic control unit. The high-voltage battery is included in the battery pack and supplies power to high-voltage devices. The relay is included in the battery pack and switches the electrical connection / disconnection between the high-voltage battery and the high-voltage devices. The interlock device includes a switch whose contact state changes in conjunction with the opening of the cover member, and outputs an interlock signal indicating that the opening has been performed according to the change in the contact state. The electronic control unit controls the relay to perform electrical disconnection according to the reception of the interlock signal.

Advantages of the Invention

[0007] According to the present disclosure, when the cover member that shields the battery pack is opened by an operator, the relay operates and the electrical connection between the high-voltage battery and the high-voltage devices is interrupted. Therefore, it becomes possible to more reliably prevent an operator who starts working on the battery pack from touching parts with high voltage applied around the battery pack.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0009] 1. Configuration of Vehicle Power Supply System 1-1. Overall Configuration FIG. 1 is a diagram schematically showing an example of the configuration of a vehicle power supply system 1 according to an embodiment. The vehicle power supply system 1 is mounted on a vehicle 100 (see FIG. 2). The vehicle 100 is an electric vehicle such as a battery electric vehicle (BEV).

[0010] The vehicle power supply system 1 includes a battery pack 10, a high-voltage device 20, an interlock device 30, and an electronic control unit (ECU) 40.

[0011] The battery pack 10 includes a high-voltage battery (or simply a battery) 11 and a system main relay (SMR) 12. The battery 11 supplies power to the high-voltage device 20 (load). The battery 11 is a secondary battery such as a lithium-ion battery. In FIG. 1, as specific examples of the high-voltage device 20, a power control unit (PCU) 21 including a converter and an inverter, and a water heater 22 are shown. The SMR 12 is a relay that switches the electrical connection / disconnection between the battery 11 and the high-voltage device 20 (i.e., each of the PCU 21 and the water heater 22).

[0012] In addition, the "high-voltage components" used in the following description include, together with the high-voltage device 20, for example, high-voltage wirings 23, 24 and high-voltage connectors 25, 26 for electrically connecting between the battery pack 10 and each high-voltage device 20.

[0013] The interlock device 30 includes a switch 31 and an interlock wire 32. The switch 31 is configured such that a change in the contact state occurs in conjunction with the opening of a "cover member" (see FIG. 2 or FIG. 3). And the interlock device 30 has a circuit that outputs an interlock signal S in response to the change in the contact state. The interlock signal S here is a signal indicating that the cover member has been opened. The interlock wire 32 connects between the switch 31 and the ECU 40 and transmits the interlock signal S to the ECU 40.

[0014] The ECU 40 executes various processes related to the control of the SMR 12. The various processes include controlling the SMR 12 to perform electrical cutoff in response to the reception of the interlock signal S from the interlock device 30. Specifically, the ECU 40 includes a processing circuit and a memory. The memory stores various information necessary for the processing by the processing circuit. By the processing circuit executing the computer program stored in the memory, the various processes by the ECU 40 are realized. Also, the various processes may be realized by hardware processing by a dedicated electronic circuit.

[0015] Also, the ECU 40 may be configured by combining a plurality of ECUs. For example, the ECU 40 may include a lower ECU that controls the SMR 12 and an upper ECU that commands the lower ECU to perform electrical cutoff of the SMR 12 in response to the reception of the interlock signal S. Also, the ECU 40 (at least the lower ECU in the case of a combination of the upper ECU and the lower ECU) may be built in the battery pack 10.

[0016] 1-2. Configuration of the Interlock Device 1-2-1. Location of the Switch FIG. 2 is a diagram for explaining an example of the location of the switch 31 with respect to the vehicle 100. In the example shown in FIG. 2, the battery pack 10 is mounted at the lower part of the vehicle 100 outside the passenger compartment 102. And the under cover 101 is formed as a cover that covers the entire battery pack 10 from below. The "cover member" according to the present disclosure is one that shields the battery pack and is opened by an operator during work on the battery pack, and the under cover 101 corresponds to an example of the cover member. Note that the opening of the cover member includes the removal of the opening.

[0017] In the vehicle 100 shown in FIG. 2, in order for an operator to perform work on the battery pack 10 (for example, work of removing the high-voltage connectors 25, 26, and the battery pack 10 itself), it is necessary to open (in other words, remove) the under cover 101. In other words, the vehicle 100 is configured such that the operator cannot touch the battery pack 10 when the under cover 101 is attached to the vehicle 100. The opening of the under cover 101 is performed, for example, during maintenance or rescue.

[0018] In the example shown in FIG. 2, the switch 31 of the interlock device 30 is disposed in the vicinity of the under cover 101. More specifically, the switch 31 is attached to, for example, a vehicle body member (not shown) located inside the under cover 101. Alternatively, the switch 31 may be attached to the inner surface of the under cover 101 facing the battery pack 10.

[0019] FIG. 3 is a diagram for explaining another example of the arrangement location of the switch 31. The vehicle 100 (see FIG. 2) is provided with a hatch 104 on the floor 103 of the passenger compartment 102. The hatch 104 is provided so that an operator can perform work on the battery pack 10 from the passenger compartment 102 side. In an example of the vehicle 100 having such a hatch 104, the switch 31 may be disposed at a location where it can detect the opening of the lid (upper lid) 104a of the hatch 104. Specifically, for example, the switch 31 may be attached to the inner surface of the lid 104a facing the battery pack 10 as shown in FIG. 3. That is, in the example shown in FIG. 3, the floor 103 including the hatch 104 corresponds to another example of the "cover member" according to the present disclosure. Alternatively, the switch 31 may be attached to a member (not shown) on the floor 103 side at a position below and in the vicinity of the lid 104a when the lid 104a is closed, rather than on the lid 104a side.

[0020] 1-2-2. Examples of realizing "change in contact state" of the switch As already described, the switch 31 of the interlock device 30 is configured such that a "change in contact state" occurs in conjunction with the opening of the cover member (for example, the under cover 101 or the lid 104a). This change in contact state is realized, for example, by the configuration shown in FIG. 4 or FIG. 5.

[0021] Note that the following descriptions of FIGS. 4 and 5 mainly target an example of the placement location of the switch 31 shown in FIG. 2 (that is, an example where the switch 31 is placed in the vicinity of the under cover 101).

[0022] 1-2-2-1. First realization example (normally closed) FIG. 4 is a diagram for explaining an example of a configuration that causes a change in the contact state of the switch 31. The switch 31 includes a lever 31a1 and a contact 31b.

[0023] FIG. 4(A) corresponds to the "normal time" when the under cover 101 is attached to the vehicle 100. As shown in FIG. 4(A), in the normal time, the lever 31a1 of the switch 31 fixed to the vehicle body member is pressed by the under cover 101 and is in contact with the contact 31b. The switch 31 is in an on state (closed state) when the lever 31a1 contacts the contact 31b in this way.

[0024] On the other hand, FIG. 4(B) shows the state where the under cover 101 is released (removed) from the vehicle 100 during "work". When the pressing force disappears due to the opening of the under cover 101, the lever 31a1 used as a leaf spring operates to separate from the contact 31b by its own restoring force as shown in FIG. 4(B). As a result, the switch 31 becomes an off state (open state).

[0025] As described above, in the first implementation example shown in FIG. 4, the switch 31 functions as a normally closed switch. That is, the "change in contact state" realized by this example is a change from the on state to the off state. Therefore, in the example shown in FIG. 4, the interlock device 30 outputs an interlock signal S in response to the change in the contact state of the switch 31 from the on state to the off state in conjunction with the opening (removal) of the under cover 101.

[0026] Note that the first implementation example is similarly applicable to an example in which the switch 31 is attached to a member on the floor 103 side located below and in the vicinity of the closed lid 104a in the vehicle 100 having the hatch 104. That is, in this example, the lever 31a1 comes into contact with / separates from the lid 104a instead of the under cover 101. Further, in an example where the switch 31 is attached to the under cover 101 or the lid 104a, the vehicle body member or the member on the floor 103 side corresponds to the member that comes into contact with / separates from the lever 31a1.

[0027] 1-2-2-2. Second Implementation Example (Normally Open) FIG. 5 is a diagram for explaining another example of a configuration that causes a change in the contact state of the switch 31. In the second implementation example, the switch 31 has a lever 31a2 instead of the lever 31a1. The lever 31a2 is used as a leaf spring and is configured to have a restoring force that acts to press the lever 31a2 against the contact point 31b. FIG. 5 corresponds to a view of the switch 31 fixed to the vehicle body member in the vicinity of the under cover 101 from the side of the battery pack 10 along the vehicle up and down direction. That is, in FIG. 5, the under cover 101 is located on the back side of the paper with respect to the switch 31.

[0028] Figure 5(A) corresponds to the "normal time" when the under cover 101 is attached to the vehicle 100. As shown in Figure 5(A), normally, a clip 105 is interposed between the lever 31a2 and the switch body 31c. The clip 105 is fixed to the under cover 101, for example. By this clip 105, the position of the lever 31a2 is regulated so that the lever 31a2 does not contact the contact point 31b by the above-mentioned restoring force. Therefore, normally, that is, when the under cover 101 is not opened by the operator, the switch 31 is in the off state (open state).

[0029] On the other hand, Figure 5(B) shows the state where the under cover 101 is opened (removed) from the vehicle 100 during "operation". The clip 105 fixed to the under cover 101 will be removed from the switch 31 when the under cover 101 is opened. As a result, since the regulation by the clip 105 is eliminated, the lever 31a2 operates to contact the contact point 31b by its own restoring force as shown in Figure 5(B). As a result, the switch 31 is in the on state (closed state).

[0030] As described above, in the second implementation example shown in Figure 5, the switch 31 functions as a normally open type switch. That is, the "change in the contact state" realized by this example is a change from the off state to the on state. Therefore, in the example shown in Figure 5, the interlock device 30 outputs an interlock signal S in response to the change in the contact state of the switch 31 from the off state to the on state in conjunction with the opening (removal) of the under cover 101.

[0031] Note that the second implementation example is similarly applicable to the example where the switch 31 is attached to a member on the floor 103 side, which is located below and in the vicinity of the lid 104a with the hatch 104 in the closed state in the vehicle 100. That is, in this example, the clip 105 is provided on the lid 104a side instead of the under cover 101. Further, in the example where the switch 31 is attached to the under cover 101 or the lid 104a, the clip 105 is provided on the vehicle body member or the member on the floor 103 side.

[0032] 2. Effects As described above, according to the vehicle power supply system 1 according to the present embodiment, when a cover member such as the under cover 101 is opened by an operator for work on the battery pack 10, an interlock signal S is output in response to a change in the contact state of the switch 31 linked to the opening, and the SMR 12 is turned off. That is, the high-voltage circuit connected to the high-voltage battery 11 is interrupted. As a result, it is possible to more reliably prevent an operator who starts work on the battery pack from touching parts to which a high voltage is applied around the battery pack. In other words, it is possible to surely ensure the safety when the operator touches high-voltage components such as the high-voltage wirings 23 and 24 and the high-voltage connectors 25 and 26 during work.

[0033] Furthermore, generally speaking, the switch 31 included in the interlock device 30 may be either a normally closed type as illustrated in FIG. 4 or a normally open type as illustrated in FIG. 5. Moreover, in the case of the normally closed type example, if a failure occurs in which the switch 31 is fixed in the on state, there may be a problem that the high-voltage circuit is not interrupted in conjunction with the opening of the cover member such as the under cover 101. In this regard, in the case of the normally open type, even if the switch 31 is fixed in the off state, only the off state is maintained after the cover member is opened and no current flows through the high-voltage circuit, and the operator can work safely. Thus, by adopting the normally open type switch 31, the possibility of problems caused by fixation can be extremely reduced.

[0034] Also, when the battery pack is mounted under the vehicle outside the vehicle compartment as in the example of the vehicle 100 shown in FIG. 2, an operator may be required to perform work on the battery pack above his / her head, for example, in a situation where there is no operation manual during rescue. In such a case, workability is poor, and the operator is likely to accidentally touch parts to which a high voltage is applied. Regarding this point, according to the example where the cover member is the under cover 101, even in such a severe working environment, since the high voltage circuit is cut off just by the operator opening the under cover 101, the work can be performed safely.

[0035] Also, although not shown in FIGS. 2 and 3, there may be high voltage components around the hatch 104. Therefore, by adopting a configuration that outputs an interlock signal S according to a change in the contact state that occurs in conjunction with the opening of the lid 104a of the hatch 104, even when the hatch 104 is used for work on the battery pack 10, it is possible to more reliably prevent an operator who starts work on the battery pack from touching parts to which a high voltage is applied around the battery pack.

Description of Reference Numerals

[0036] 1 Vehicle power supply system, 10 Battery pack, 11 High voltage battery, 20 High voltage equipment, 23, 24 High voltage wiring, 25, 26 High voltage connectors, 30 Interlock device, 31 Switch, 31a1, 31a2 Levers, 31b Contacts, 32 Interlock wire, 100 Vehicle, 101 Under cover, 103 Floor, 104 Hatch, 104a Lid of the hatch, 105 Clip

Claims

1. A vehicle power supply system applied to a vehicle comprising a cover member that shields a battery pack and is opened by an operator during work on the battery pack, a high-voltage battery included in the battery pack that supplies power to high-voltage devices, a relay included in the battery pack that switches electrical connection / interruption between the high-voltage battery and the high-voltage devices, an interlock device including a switch whose contact state changes in conjunction with the opening of the cover member, and outputs an interlock signal indicating that the opening has been performed in response to the change in the contact state, an electronic control unit that controls the relay to perform the electrical interruption in response to the reception of the interlock signal, and comprising A vehicle power supply system characterized by the above.

2. The vehicle power supply system according to claim 1, wherein the switch has a contact that is in an off state when the opening is not performed by the operator and is in an on state in response to the opening, and the interlock device outputs the interlock signal in response to the contact being in the on state. A vehicle power supply system characterized by the above.

3. The vehicle power supply system according to claim 1 or 2, wherein the battery pack is mounted below the vehicle outside the vehicle compartment, and the cover member is a cover that covers the entire battery pack from below. A vehicle power supply system characterized by the above.

4. The vehicle power supply system according to claim 1 or 2, wherein the cover member includes a hatch for working on the battery pack, and the change in the contact state occurs in conjunction with the opening of the lid of the hatch. A vehicle power supply system characterized by the above.

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