Vehicle power supply system

Abstract

A vehicle power supply system (1) is provided with a first power supply system (10) that supplies power from a first power supply (41) to a first load (11) related to travel control of a vehicle (V), and a second power supply system (20) that supplies power from a second power supply (42) to a second load (21) related to travel control of the vehicle (V), and is provided with: a system connection unit (SW3) that connects the first power supply system (10) to the second power supply system (20); the first power supply system (10) and the second power supply system (20) can be connected and disconnected; a second power supply connection unit (SW2) capable of connecting and disconnecting a second power supply (42) and a second load (21); and a control unit (211) that switches the second power supply connection unit (SW2) from the connection state to the disconnection state and switches the system connection unit (SW3) from the disconnection state to the connection state when an abnormality is detected in the second power supply (42).

Description

Technical Field

[0001] The present invention relates to a vehicle power supply system mounted on a vehicle. Background Art

[0002] As a technique of this kind, there is known a vehicle power supply system in which at least part of the functions of the control device 1A and the control device 1B are multiplexed and redundant to improve the reliability of the system (see, for example, Patent Document 1).

[0003] Conventionally, since both the power supply system including the control device 1A and the power supply system including the control device 1B require batteries, this is a major factor hindering cost reduction and miniaturization of the vehicle power supply system.

[0004] Since the vehicle power system is small and light, energy efficiency can be improved. In addition, since the cost of the vehicle power system is reduced, the popularization of the vehicle power system can be promoted, which contributes to the development of a sustainable transportation system.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent document 1: Japanese Patent Application Publication No. 2020-152139 (JP 2020-152139A). Summary of the invention

[0008] A vehicle power supply system according to one technical solution of the present invention is a vehicle power supply system comprising a first power supply system for supplying power from a first power supply to a first load related to driving control of a vehicle, and a second power supply system for supplying power from a second power supply to a second load related to driving control of the vehicle, the vehicle power supply system comprising: a system connection unit capable of connecting and disconnecting the first power supply system and the second power supply system; a second power supply connection unit capable of connecting and disconnecting the second power supply and the second load; and a control unit which switches the second power supply connection unit from a connected state to a disconnected state, and switches the system connection unit from a disconnected state to a connected state, when an abnormality is detected in the second power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The objects, features and advantages of the present invention will be further clarified through the following description of the embodiments in conjunction with the accompanying drawings.

[0010] Figure 1 It is a schematic diagram illustrating the configuration of a vehicle power supply system according to an embodiment of the invention.

[0011] Figure 2A is a schematic diagram illustrating a vehicle power supply system.

[0012] Figure 2Bis a schematic diagram illustrating a vehicle power supply system.

[0013] Figure 2C is a schematic diagram illustrating a vehicle power supply system.

[0014] Figure 2D is a schematic diagram illustrating a vehicle power supply system.

[0015] Figure 3 This is a flowchart illustrating the flow of switch switching control.

[0016] Figure 4 1 is a schematic diagram illustrating a configuration of a vehicle power supply system according to Modification 1.

[0017] Figure 5 1 is a schematic diagram illustrating a configuration of a vehicle power supply system according to a second modification.

[0018] Fig. 6A is a schematic diagram illustrating a vehicle power supply system.

[0019] Figure 6B is a schematic diagram illustrating a vehicle power supply system.

[0020] Figure 6C is a schematic diagram illustrating a vehicle power supply system.

[0021] Fig.6D is a schematic diagram illustrating a vehicle power supply system. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0023] <Outline>

[0024] A vehicle power supply system according to one embodiment of the present invention improves system reliability by duplexing and redundantly providing at least a portion of the functions of a first load as a first control device and a second load as a second control device, and achieves cost reduction and miniaturization by providing a battery in only one of the first power supply system having the first load and the second power supply system having the second load, compared to a vehicle power supply system in which batteries are respectively provided in the first power supply system and the second power supply system.

[0025] Such a vehicle power supply system will be described in detail below.

[0026] <Structure of vehicle power supply system>

[0027] Figure 1 1 is a schematic diagram illustrating a configuration of a vehicle power supply system 1 which is a vehicle power supply system mounted on a vehicle V, that is, according to an embodiment. Figure 1The operating states of the switches SW1, SW2, and SW3 included in show the normal operating states.

[0028] In the embodiment, the normal state refers to a state where the ignition (IG) switch (not shown) is turned on and the vehicle power supply system 1 does not have any abnormality described below. Figure 1 The switching state shown as an example is called a normal setting.

[0029] The vehicle power supply system 1 comprises: a first power supply system 10; a second power supply system 20 arranged in parallel with the first power supply system 10, a high-voltage power supply system 30 having a higher voltage than the first power supply system 10 and the second power supply system 20; and a system connection unit (switch SW3, more specifically, connection line L60 and switch SW3) capable of switching connection and disconnection between the first power supply system 10 and the second power supply system 20.

[0030] <First power supply system>

[0031] The power supply system that supplies power to the first load 11 is referred to as a first power supply system 10. The first power supply system 10 includes a first power supply 41, a first load 11, a switch SW1 as a first power supply connection portion capable of switching connection and disconnection between the first power supply 41 and the first load 11, and a first battery 12 connected to the first load 11 side of the switch SW1.

[0032] (First power source)

[0033] The first power supply 41 includes a DC-DC converter that converts a DC voltage (eg, 200 [V]) supplied from the high-voltage power supply system 30 into a voltage required by the first load 11. The first power supply 41 outputs a DC voltage (eg, 12 [V]) after the DC-DC conversion.

[0034] (Switch SW1)

[0035] The first power supply 41 and the first load 11 are connected via the power line L10. The switch SW1 is provided on the first power supply 41 side of the power line L10. The switch SW1 is a normally open (NO type) switch composed of, for example, a semiconductor switch. The normally open switch is in an off state when no switching control signal is input, and can switch the on / off state when a switching control signal is input. Therefore, it is configured so that a switching control signal to the on state is input to the switch SW1 in normal times, whereby the DC voltage after DC-DC conversion in the first power supply 41 is supplied to the first load 11 via the switch SW1 in the on state and the power line L10.

[0036] It should be noted that the switching of the switch SW1 is controlled by at least the power from the first power supply 41 of the first power supply system 10. In other words, normally, the ECU 111 described in detail later receives the power from the first power supply 41 of the first power supply system 10 to control the switching of the switch SW1. On the other hand, it can also be configured so that when the ECU 111 cannot receive the power supply from the first power supply 41, another control device (not shown) that operates by receiving the power from the high-voltage power supply 31 of the high-voltage power supply system 30 controls the switching of the switch SW1, thereby maintaining redundancy.

[0037] (First load)

[0038] The first load 11 includes a load that assumes functions related to the driving operation, stop operation, or driving control of the vehicle V for the automatic driving (AD) function. As an example, the first load 11 includes at least one of an auxiliary load for driving control for AD of the vehicle V such as an ECU (Electronic Control Unit), an auxiliary load for braking for AD of the vehicle V, an auxiliary load for steering for AD of the vehicle V, and an auxiliary load for obtaining external information for AD of the vehicle V such as LiDAR (Light Detection And Ranging) and a camera.

[0039] In the embodiment, as the first load 11, there is an ECU 111 for driving control for AD of the vehicle V, a brake control device 112 for controlling a brake device for braking of the vehicle V, a steering control device 113 for controlling a steering device for steering of the vehicle V, and an external information processing device 114 for processing input information for AD from a LiDAR or a camera for obtaining external information of the vehicle V.

[0040] In addition, the first load 11 includes emergency non-priority auxiliary loads 117 as auxiliary loads other than the above-mentioned AD auxiliary loads. For example, the emergency non-priority auxiliary loads 117 include headlights 117a, wiper devices 117b, power window devices 117c, and instruments 117d.

[0041] In addition, when the vehicle V includes an engine (not shown), the first load 11 may include a starter motor (not shown) for starting the engine.

[0042] (First Battery)

[0043] The first battery 12 includes a secondary battery that can be repeatedly charged and discharged. In the embodiment, the first battery 12 is composed of, for example, a lithium ion battery. Thus, the state of the first battery 12 can be easily and accurately estimated by known means and methods. The first battery 12 outputs power at a voltage of, for example, 12 [V].

[0044] The positive electrode of the first battery 12 is connected to a contact point C11 formed on the power line L10 on the first load 11 side relative to the switch SW1, and the negative electrode is connected to a ground line having a reference potential of the vehicle power supply system 1. It should be noted that, although not shown in the figure, since a charge and discharge control circuit for a secondary battery is provided in parallel, the first battery 12 is protected from overcharge and overdischarge.

[0045] <Second power supply system>

[0046] The power supply system that supplies power to the second load 21 is referred to as a second power supply system 20. The second power supply system 20 includes a second power supply 42, a second load 21, and a switch SW2 as a second power supply connection portion capable of switching connection and disconnection between the second power supply 42 and the second load 21.

[0047] The second power supply system 20 is different from the first power supply system 10 in that it does not include a secondary battery like the first battery 12 .

[0048] (Second power supply)

[0049] The second power supply 42 includes a DC-DC converter that converts a DC voltage (eg, 200 [V]) supplied from the high-voltage power supply system 30 into a voltage required by the second load 21. The second power supply 42 outputs a DC voltage (eg, 12 [V]) after the DC-DC conversion.

[0050] (Switch SW2)

[0051] The second power supply 42 and the second load 21 are connected via the power line L20. The switch SW2 is provided on the second power supply 42 side of the power line L20. The switch SW2 is the same as the switch SW1, and is a normally open (NO) switch composed of, for example, a semiconductor switch. Therefore, since it is configured so that a switching control signal to the on state is input to the switch SW2 in normal times, the DC voltage after the DC-DC conversion in the second power supply 42 is applied to the second load 21 via the switch SW2 in the on state and the power line L20.

[0052] It should be noted that the switching of the switch SW2 is controlled by using the power from the second power supply 42 of the second power supply system 20 and the high-voltage power supply 31 of the high-voltage power supply system 30. In other words, normally, the ECU 211 described in detail later receives the power from the second power supply 42 of the second power supply system 20 to control the switching of the switch SW2. On the other hand, when the ECU 211 cannot receive the power supply from the second power supply 42, another control device (not shown) that operates by receiving the power from the high-voltage power supply 31 of the high-voltage power supply system 30 controls the switching of the switch SW2, thereby maintaining redundancy.

[0053] (Second load)

[0054] The second load 21 includes a load that assumes functions related to the driving operation, stop operation, or driving control of the vehicle V for the advanced driving assistance system (ADAS) function. The second load 21 assumes functions related to executing the minimum risk strategy (MRM: Minimal Risk Maneuver), which is the minimum necessary driving operation, stop operation, and driving control for safely moving the vehicle V to the shoulder of the road and the like and stopping when an abnormality occurs in the first power supply system 10.

[0055] As an example, the second load 21 includes at least one of an auxiliary load such as an ECU for driving control for ADAS of the vehicle V, an auxiliary load such as a braking load for ADAS of the vehicle V, an auxiliary load such as a steering load for ADAS of the vehicle V, and an auxiliary load such as a LiDAR and a camera for obtaining external information for ADAS of the vehicle V.

[0056] In the embodiment, as the second load 21, there is an ECU 211 for driving control for ADAS of the vehicle V, a braking control device 212 for controlling a braking device for braking of the vehicle V, a steering control device 213 for controlling a steering device for steering of the vehicle V, and an external information processing device 214 for processing input information for ADAS from LiDAR and a camera for obtaining external information of the vehicle V.

[0057] A portion of the loads included in the second load 21 of the second power supply system 20 is a load having functions that overlap with a portion of the first load 11 of the first power supply system 10. Specifically, the ECU 211 of the second load 21 overlaps the functions of the ECU 111 of the first load 11, the brake control device 212 of the second load 21 overlaps the functions of the brake control device 112 of the first load 11, the steering control device 213 of the second load 21 overlaps the functions of the steering control device 113 of the first load 11, and the external information processing device 214 of the second load 21 overlaps the functions of the external information processing device 114 of the first load 11.

[0058] In this way, by duplicating a part of the functions between the second load 21 of the second power supply system 20 and the first load 11 of the first power supply system 10, even if an abnormality occurs in the first power supply system 10 or the second power supply system 20, the functions related to the MRM for performing the minimum necessary driving operation, stop operation, and driving control for safely moving the vehicle V to the shoulder of the road and the like and stopping can be multiplexed and redundant. That is, even if an abnormality occurs in either the first power supply system 10 or the second power supply system 20, and either the first load 11 or the second load 21 does not function, the MRM can be performed using the load of the other power supply system, thereby providing a vehicle power supply system 1 that ensures traffic safety.

[0059] <High-voltage power supply system>

[0060] The high-voltage power supply system 30 includes a high-voltage power supply 31 and a high-voltage load 32. The high-voltage power supply 31 and the high-voltage load 32 are connected via a power line L31 and a power line L32.

[0061] (High voltage power supply)

[0062] The high-voltage power supply 31 includes a secondary battery such as a lithium-ion battery. The high-voltage power supply 31 outputs a DC power having a higher voltage (e.g., 200 [V]) than the first battery 12. It should be noted that, although not shown in the figure, a charge and discharge control circuit for the secondary battery is provided in parallel with the high-voltage power supply 31 to protect the secondary battery constituting the high-voltage power supply 31 from overcharging and overdischarging.

[0063] The positive electrode side of the high-voltage power supply 31 is connected to a contact point C32 formed on the power line L31 , and the negative electrode side is connected to a ground line having a reference potential of the vehicle power supply system 1 .

[0064] (High voltage load)

[0065] The high-voltage load 32 operates at a voltage higher than the first load 11 and the second load 21 (eg, 200 [V]). In the embodiment, the high-voltage load 32 includes a drive unit 321 for driving the vehicle V and an air conditioner 322 for adjusting the temperature in the vehicle cabin.

[0066] The drive unit 321 includes a rotary electric machine MG that generates power for driving the vehicle V and a power control unit PCU that controls the rotary electric machine MG. The power control unit PCU includes a DC-DC converter, an inverter, and the like.

[0067] The drive unit 321 is connected to a contact point C31 formed on the power line L31. The drive unit 321 converts the DC power supplied from the high-voltage power source 31 via the power line L31 into three-phase AC power through the power control unit PCU, and supplies it to the rotary electric machine MG. Then, the rotary electric machine MG generates power to drive the vehicle V using the three-phase AC power. In addition, when the vehicle V is braked, the drive unit 321 generates three-phase AC power through the rotary electric machine MG, converts the three-phase AC power into DC power through the power control unit PCU, and charges the high-voltage power source 31 via the power line L31.

[0068] The air conditioner 322 is connected to the connection point C31 via the power line L32. The air conditioner 322 is operated by the direct current supplied from the high-voltage power supply 31.

[0069] <Connection between the high-voltage power supply system and the first power supply system and the second power supply system>

[0070] The high-voltage power supply system 30 and the first power supply system 10 and the high-voltage power supply system 30 and the second power supply system 20 are connected via the power line L50 and the power line L40 .

[0071] One end of the power line L50 is connected to the above-mentioned contact point C32 of the high-voltage power supply system 30 , and the other end is connected to a contact point C41 formed on the power line L40 .

[0072] One end of the power line L40 is connected to the input side of the first power source 41, and the other end is connected to the input side of the second power source 42. A contact point C41 formed on the power line L40 is connected to the positive electrode of the high voltage power source 31 via the power line L50.

[0073] Through the above connection, direct current power from the high voltage power source 31 is supplied to the first power source 41 and the second power source 42 via the power line L50 and the power line L40 .

[0074] <System connection section>

[0075] The connection line L60 and the switch SW3 as a system connection portion switch the connection state and the disconnection state between the first power supply system 10 and the second power supply system 20 .

[0076] One end of the connection line L60 is connected to a connection point C12 formed on the power line L10 of the first power supply system 10 , and the other end is connected to a connection point C21 formed on the power line L20 of the second power supply system 20 .

[0077] (Switch SW3)

[0078] A switch SW3 is provided on the connection line L60 so as to be able to switch between the connection state and the disconnection state of the connection line L60. The switch SW3 is a normally closed (NC type) switch composed of, for example, a semiconductor switch. The normally closed switch is in the on state when no switching control signal is input, and can switch between the on / off state when a switching control signal is input. Therefore, since the switching control signal to the disconnection state is input to the switch SW3 in the normal state, the connection line L60 is maintained in the disconnection state.

[0079] It should be noted that the switching of the switch SW3 is controlled by using the power from the first power supply 41 of the first power supply system 10 or the second power supply 42 of the second power supply system 20 and the high-voltage power supply 31 of the high-voltage power supply system 30. In other words, the ECU 111 that normally receives the power from the first power supply 41 of the first power supply system 10 or the ECU 211 that receives the power from the second power supply 42 of the second power supply system 20 controls the switching of the switch SW3. On the other hand, when the ECU 111 (or ECU 211) that performs the switching control cannot receive the power supply from the first power supply 41 (or the second power supply 42), another control device (not shown) that operates by receiving the power from the high-voltage power supply 31 of the high-voltage power supply system 30 controls the switching of the switch SW3, thereby maintaining redundancy.

[0080] <Operation when the vehicle power system is abnormal>

[0081] Next, the operation of the vehicle power supply system 1 when an abnormality occurs in the vehicle power supply system 1, that is, when the operation is different from the normal state, will be described. Specifically, the switching control of the switches SW1, SW2, and SW3 will be described.

[0082] (High voltage fault)

[0083] Figure 2A A high voltage failure is a state in which the first power supply 41 and the second power supply 42 do not receive power from the high voltage power supply system 30 due to some abnormality in the high voltage power supply 31 of the high voltage power supply system 30.

[0084] When the switch control signal is no longer input from the ECU 111 that has detected the high voltage fault, the switch SW1 disconnects the power line L10 between the first power source 41 and the first load 11. As described above, the switch SW1 is a normally open switch.

[0085] Similarly, when the switch control signal is no longer input from the ECU 211 that has detected the high voltage failure, the switch SW2 disconnects the power line L20 between the second power source 42 and the second load 21. As described above, the switch SW2 is a normally open switch.

[0086] When no switching control signal is input from the ECU 111 or ECU 211 (or other control device that operates by receiving power from the high voltage power supply 31) that detects a high voltage failure, the switch SW3 connects the connection line L60 between the first power supply system 10 and the second power supply system 20. As described above, the switch SW3 is a normally closed switch.

[0087] Set switches SW1, SW2, and SW3 to Figure 2A The switching state illustrated in the example is called the first setting at the time of failure. In the first setting at the time of failure, the first power supply 41 and the first load 11 are disconnected by the switch SW1 in the off state. In addition, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the off state. In addition, the first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the on state.

[0088] In addition, the first battery 12 connected to the power line L10 of the first power supply system 10 supplies the power required for the operation of the first load 11 to the first load 11, and supplies the power required for the operation of the second load 21 of the second power supply system 20 to the second load 21 via the connection line L60 serving as the system connection part and the switch SW3.

[0089] Because of this structure, even if the power supply from the high-voltage power supply system 30 to the first power supply system 10 and the second power supply system 20 is stopped due to a high-voltage failure, the vehicle power supply system 1 with redundancy can be realized in a manner that the functions related to the execution of the MRM are maintained by the functions of the first load 11 or the second load 21, and traffic safety is further improved. The MRM is the minimum necessary driving operation, stop operation, and driving control for the vehicle V to safely move to the shoulder of the road and stop. At this time, the power supply source to the first load 11 and the second load 21 is only the first battery 12 provided in the first power supply system 10. Compared with the case where the first power supply system 10 and the second power supply system 20 each have a battery, the number of batteries can be reduced, which contributes to the miniaturization and cost reduction of the vehicle power supply system.

[0090] It should be noted that Figure 2AThe switching states of switches SW1, SW2, and SW3 illustrated in the example are also applicable to a situation where, although 200 [V] of power is supplied from the high-voltage power supply system 30 to the first power supply 41 of the first power supply system 10 and the second power supply 42 of the second power supply system 20, due to some abnormality in both the first power supply 41 and the second power supply 42, the DC-DC converted 12 [V] voltage cannot be output from both the first power supply 41 and the second power supply 42.

[0091] (First load abnormality)

[0092] Figure 2B 1 is a schematic diagram of a vehicle power supply system for explaining an abnormality in the first load 11. A state in which the first load 11 is grounded or short-circuited due to some abnormality occurring in the first load 11 of the first power supply system 10 is referred to as a first load abnormality. In the following description, the first load abnormality is sometimes referred to as Gr1 grounding.

[0093] When the switch control signal is no longer input from the ECU 111 that has detected the abnormality of the first load, the switch SW1 disconnects the power line L10 between the first power source 41 and the first load 11. As described above, the switch SW1 is a normally open switch.

[0094] When the switching control signal is continuously input from the ECU 211 (or another control device that operates by receiving power from the high-voltage power supply 31), the switch SW2 maintains the connection of the power line L20 between the second power supply 42 and the second load 21. As described above, the switch SW2 is a normally open switch.

[0095] When the switch control signal is continuously input from the ECU 111 or ECU 211 (or other control device operated by receiving power from the high voltage power supply 31), the switch SW3 maintains the disconnection of the connection line L60 between the first power supply system 10 and the second power supply system 20. As described above, the switch SW3 is a normally closed switch.

[0096] Set switches SW1, SW2, and SW3 to Figure 2B The switching state illustrated in the example is called the second setting at the time of failure. In the second setting at the time of failure, the power supply from the first power supply 41 to the first load 11 that has been grounded or short-circuited is disconnected by the switch SW1 in the disconnected state. On the other hand, the power supply from the second power supply 42 to the second load 21 is maintained by the switch SW2 in the on state. In addition, the disconnection between the first power supply system 10 and the second power supply system 20 is maintained by the switch SW3 in the off state.

[0097] Because of this structure, even if the function of the first load 11 stops due to an abnormality in the first load, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the function related to the execution of MRM is maintained by the function of the second load 21, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0098] It should be noted that Figure 2B The switching states of the switches SW1, SW2, and SW3 illustrated in the figure can also be applied to a situation where, although 200 [V] of power is supplied from the high-voltage power supply system 30 to the first power supply 41 of the first power supply system 10, due to some abnormality in the first power supply 41, the voltage of 12 [V] after DC-DC conversion cannot be output from the first power supply 41 (also referred to as a first power supply abnormality) and a situation where some abnormality occurs in the first battery 12 or in a charge and discharge control circuit not shown in the figure and arranged in parallel with the first battery 12 (also referred to as a first battery abnormality).

[0099] (Second load abnormality)

[0100] Figure 2C Schematic diagram of the vehicle power supply system for explaining the abnormality of the second load 21. The state where the second load 21 is grounded or short-circuited due to some abnormality in the second load 21 of the second power supply system 20 is called the second load abnormality. In the following description, the second load abnormality is sometimes referred to as Gr2 grounding.

[0101] The switch SW1 maintains the connection of the power line L10 between the first power source 41 and the first load 11 when the switching control signal continues to be input from the ECU 111. As described above, the switch SW1 is a normally open switch.

[0102] When the switch control signal is no longer input from the ECU 211 (or other control device operated by receiving power from the high-voltage power supply 31) that detects the abnormality of the second load, the switch SW2 disconnects the power line L20 between the second power supply 42 and the second load 21. As described above, the switch SW2 is a normally open switch.

[0103] When the switch control signal is continuously input from the ECU 111 or ECU 211 (or other control device operated by receiving power from the high voltage power supply 31), the switch SW3 maintains the disconnection of the connection line L60 between the first power supply system 10 and the second power supply system 20. As described above, the switch SW3 is a normally closed switch.

[0104] Set switches SW1, SW2, and SW3 to Figure 2CThe switching state illustrated in the example is called the third setting at the time of failure. In the third setting at the time of failure, the power supply from the second power supply 42 to the second load 21 that is grounded or short-circuited is disconnected by the switch SW2 in the disconnected state. On the other hand, the power supply from the first power supply 41 to the first load 11 is maintained by the switch SW1 in the on state. In addition, the disconnection between the first power supply system 10 and the second power supply system 20 is maintained by the switch SW3 in the disconnected state.

[0105] Because of this structure, even if the function of the second load 21 stops due to an abnormality in the second load, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the function related to the execution of MRM is maintained by the function of the first load 11, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0106] (Second power supply abnormality)

[0107] Figure 2D This is a schematic diagram of the vehicle power supply system for explaining an abnormality in the second power supply 42. The situation where the DC-DC converted 12 [V] voltage cannot be output from the second power supply 42 due to an abnormality in the second power supply system 20 is called a second power supply abnormality.

[0108] The switch SW1 maintains the connection of the power line L10 between the first power source 41 and the first load 11 when the switching control signal continues to be input from the ECU 111. As described above, the switch SW1 is a normally open switch.

[0109] When the switch control signal is no longer input from the ECU 211 (or other control device operated by receiving power from the high-voltage power supply 31) that detects the abnormality of the second power supply, the switch SW2 disconnects the power line L20 between the second power supply 42 and the second load 21. As described above, the switch SW2 is a normally open switch.

[0110] When the switching control signal is no longer input from the ECU 111 or ECU 211 (or other control device that operates by receiving power from the high-voltage power supply 31) that detects the abnormality of the second power supply, the switch SW3 connects the connection line L60 between the first power supply system 10 and the second power supply system 20. As described above, the switch SW3 is a normally closed switch.

[0111] Set switches SW1, SW2, and SW3 to Figure 2DThe switching state illustrated in the example is called the fourth setting at the time of failure. In the fourth setting at the time of failure, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the off state. On the other hand, the power supply from the first power supply 41 to the first load 11 is maintained by the switch SW1 in the on state. In addition, the first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the on state.

[0112] The first power supply 41 supplies power required for the operation of the first load 11 to the first load 11 , and supplies power required for the operation of the second load 21 of the second power supply system 20 to the second load 21 via the connection line L60 as a system connection portion and the switch SW3 .

[0113] Because of this structure, even if the power supply in the second power supply system 20 is stopped due to an abnormality in the second power supply, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the functions related to the execution of MRM are maintained by the functions of the first load 11, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0114] <Explanation of the flow chart>

[0115] Figure 3 The flowchart is a flowchart for explaining the switching control process of the switches SW1, SW2 and SW3. The predetermined control device (ECU111 or ECU211 (or other control device operated by receiving power from the high voltage power supply 31)) executes according to a pre-prepared program. Figure 3 Switching control processing.

[0116] The control device repeats the operation with the ignition (IG) switch on. Figure 3 processing.

[0117] In step S10, the control device performs normal settings and proceeds to step S20. The normal settings correspond to Figure 1 2 and 3. The switching states of switches SW1, SW2 and SW3 are illustrated in FIG.

[0118] In step S20, the control device determines whether there is a high voltage fault. If a high voltage fault is detected, the control device determines step S20 as positive (S20: Yes) and proceeds to step S30. If no high voltage fault is detected, the control device determines step S20 as negative (S20: No) and proceeds to step S50.

[0119] In step S30, the control device performs the first setting when a fault occurs, and then proceeds to step S40. The first setting when a fault occurs corresponds to Figure 2A2 and 3. The switching states of switches SW1, SW2 and SW3 are illustrated in FIG.

[0120] In step S40, the control device determines whether FOF (Fail Operational Function) has ended. The control device, for example, sends a TOR (Take Over Request) while continuing the function through weakening control (MRM). When safety assurance is completed until the driving takeover is completed, the control device determines that step S40 is affirmative (S40: Yes) and ends. Figure 3 processing.

[0121] On the other hand, when FOF is not completed, the control device determines that step S40 is negative (S40: No) and waits for FOF to be completed.

[0122] In step S50, the control device determines whether Gr1 is grounded when step S20 is determined to be negative (S20: No). When the control device detects that the first load is abnormal, the control device determines that step S50 is positive (S50: Yes) and proceeds to step S60. When the control device does not detect that the first load is abnormal, the control device determines that step S50 is negative (S50: No) and proceeds to step S80.

[0123] In step S60, the control device performs the second setting in case of failure, and then proceeds to step S70. The second setting in case of failure corresponds to Figure 2B 2 and 3. The switching states of switches SW1, SW2 and SW3 are illustrated in FIG.

[0124] In step S70, the control device determines whether FOF is completed. For example, the control device continues the function by weakening control (MRM) while issuing TOR. When safety assurance is completed until the driving takeover is completed, the control device determines that step S70 is affirmative (S70: Yes) and ends. Figure 3 processing.

[0125] On the other hand, when FOF is not completed, the control device determines that step S70 is negative (S70: No), and waits for FOF to be completed.

[0126] In step S80 entered when the determination in step S50 is negative, the control device determines whether Gr2 is grounded. If the control device detects that the second load is abnormal, the determination in step S80 is positive (S80: Yes), and the process proceeds to step S90. If the control device does not detect that the second load is abnormal, the determination in step S80 is negative (S80: No), and the process proceeds to step S110.

[0127] In step S90, the control device performs the third setting in case of failure, and then proceeds to step S100. The third setting in case of failure corresponds to Figure 2C2 and 3. The switching states of switches SW1, SW2 and SW3 are illustrated in FIG.

[0128] In step S100, the control device determines whether FOF is completed. For example, the control device continues the function by weakening control (MRM) while issuing TOR. When safety assurance is completed until the driving takeover is completed, the control device determines that step S100 is affirmative (S100: Yes) and ends. Figure 3 processing.

[0129] On the other hand, when FOF is not completed, the control device determines that step S100 is negative (S100: No), and waits for FOF to be completed.

[0130] In step S110 entered when the determination in step S80 is negative, the control device determines whether the second power supply is abnormal. If the control device detects that the second power supply is abnormal, the determination in step S110 is positive (S110: Yes), and the process proceeds to step S120. If the control device does not detect that the second power supply is abnormal, the determination in step S110 is negative (S110: No), and the process proceeds to step S140.

[0131] In step S120, the control device performs the fourth setting in case of failure, and then proceeds to step S130. The fourth setting in case of failure corresponds to Figure 2D 2 and 3. The switching states of switches SW1, SW2 and SW3 are illustrated in FIG.

[0132] In step S130, the control device determines whether FOF is completed. For example, the control device continues the function by weakening control (MRM) while issuing TOR. When safety assurance until the driving takeover is completed is completed, the control device determines that S130 is affirmative (S130: Yes) and ends. Figure 3 processing.

[0133] On the other hand, when FOF is not completed, the control device determines that step S130 is negative (S130: No), and waits for FOF to be completed.

[0134] In step S140 entered when the determination of step S110 is negative, the control device determines whether the end operation has been performed. When the ignition (IG) switch is turned off, the control device determines that step S140 is positive (S140: Yes) and enters step S150. When the ignition (IG) switch is not turned off, the control device determines that step S140 is negative (S140: No) and returns to step S20.

[0135] In step S150, the control device performs IG disconnection setting, and ends Figure 3 When the IG is disconnected, the switching states of the switches SW1, SW2, and SW3 are the same as Figure 2AThat is, the first power supply 41 and the first load 11 are disconnected by the switch SW1 in the off state. In addition, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the off state. In addition, the first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the on state.

[0136] According to the above-described embodiment, the following effects are obtained.

[0137] (1) The vehicle power supply system 1 includes: a first power supply system 10 that supplies power from a first power supply 41 to a first load 11 related to the driving control of the vehicle V; a second power supply system 20 that supplies power from a second power supply 42 to a second load 21 related to the driving control of the vehicle V; a switch SW3 (more specifically, a connection line L60 and the switch SW3) that serves as a system connection unit and can connect and disconnect the first power supply system 10 and the second power supply system 20; a switch SW2 that serves as a second power supply connection unit and can connect and disconnect the second power supply 42 and the second load 21; and an ECU 211 that serves as a control unit and switches the switch SW2 from a connected state to a disconnected state and switches the system connection unit from a disconnected state to a connected state when an abnormality is detected in the second power supply 42. The ECU 211 outputs a switching control signal (a first control signal) for switching the switch SW3 between the connected state and the disconnected state, thereby switching the connection and disconnection between the first power supply system 10 and the second power supply system 20. In addition, the ECU 211 outputs a switching control signal (second control signal) for switching the connection state and disconnection state of the switch SW2 to the switch SW2, thereby switching the connection and disconnection between the second power supply 42 and the second load 21. The switch SW3 is a normally closed switch configured to maintain the connection state when the first control signal is not input. The switch SW2 is a normally open switch configured to maintain the disconnection state when the second control signal is not input. When the ECU 211 detects an abnormality in the second power supply 42, it stops the output of the first control signal and the second control signal.

[0138] Because of this configuration, the vehicle power supply system 1 having redundancy can be realized without having batteries in the first power supply system 10 and the second power supply system 20. That is, even if the power supply in the second power supply system 20 is stopped due to an abnormality in the second power supply 42, the function related to the execution of the MRM can be maintained by the function of the first load 11. Compared with the case where batteries are provided in the first power supply system 10 and the second power supply system 20, the vehicle power supply system 1 of the embodiment can reduce the number of batteries, which can contribute to the miniaturization and cost reduction of the system.

[0139] (2) In the vehicle power supply system 1 of (1) above, a switch SW1 as a first power supply connection portion capable of connecting and disconnecting the first power supply 41 and the first load 11 is further provided. The first power supply system 10 includes a first battery 12 capable of supplying power to the first load 11. When an abnormality is detected in the first power supply 41, the ECU 111 switches the switch SW1 from a connected state to a disconnected state. The ECU 211 outputs a switching control signal (third control signal) for switching the connected state and the disconnected state of the switch SW1 to the switch SW1, thereby switching the connection and disconnection between the first power supply 41 and the first load 11. The switch SW1 is a normally open switch configured to maintain a disconnected state when the third control signal is not input. When the ECU 211 detects an abnormality in the first power supply 41, it stops outputting the third control signal.

[0140] With this configuration, even if the power supply in the first power supply system 10 stops due to an abnormality in the first power supply 41 , the function related to the execution of the MRM can be maintained by the function of the first load 11 or the second load 21 .

[0141] (3) In the vehicle power supply system 1 of (2) above, the first load 11 includes an AD ECU 111 as a first control device related to the steering operation or braking operation of the vehicle V, a brake control device 112, a steering control device 113 and an external information processing device 114, and the second load 21 includes an ADAS ECU 211 as a second control device related to the driving assistance of the vehicle V, a brake control device 212, a steering control device 213 and an external information processing device 214.

[0142] Since the functions of the first load 11 and the second load 21 are overlapped in this way, even if one of the first load 11 and the second load 21 does not function, the function related to the execution of the MRM can be maintained by the function of the other load.

[0143] (4) In the vehicle power supply system 1 of (3) above, the first power supply 41 and the second power supply 42 respectively convert power from the high voltage power supply 31 of the second battery as driving power supplied to the vehicle V to generate power supplied to the first load 11 and the second load 21.

[0144] Based on the power supplied from a large-capacity high-voltage power supply 31 that supplies vehicle driving power that is larger than the power required by the auxiliary loads, the power supplied to the first load 11 and the second load 21 as auxiliary loads is generated. Because of this structure, the functions related to the execution of the MRM can be maintained without causing power shortage.

[0145] (5) In the vehicle power supply system 1 of the above (4), the switch SW3 as the system connection part is operated by the power supplied from the high-voltage power supply 31 and one of the first power supply system 10 or the second power supply system 20, and the switch SW2 as the second power supply connection part is operated by the power supplied from the high-voltage power supply 31 and one of the second power supply system 20.

[0146] With this configuration, the switches SW2 and SW3 can each be reliably switched based on the power from a plurality of power sources, thereby maintaining redundancy.

[0147] The above-described embodiment can be modified in various forms. Modifications will be described below.

[0148] (Variant 1)

[0149] The second power supply system 20 in the embodiment may include a capacitor (also referred to as a super capacitor) for preventing an instantaneous interruption of the power supplied to the second load 21 .

[0150] Figure 4 is a schematic diagram for explaining a vehicle power supply system 1 according to a first modification, and Figure 2D In the first variant, the fourth setting at the time of failure performed when the second power supply is abnormal sets the switches SW1, SW2, and SW3 to Figure 4 The switching state is illustrated in FIG.

[0151] exist Figure 4 In the embodiment, capacitor 22 is connected to contact C22 provided on switch SW2 side on power line L20 via switch 23. Switch 23 is set to an OFF state only when the ignition (IG) switch is OFF, and is always controlled to switch to an ON state when the ignition (IG) switch is ON.

[0152] Capacitor 22 is configured to be repeatedly charged and discharged, and has one electrode connected to a contact point C22 of power line L20 via switch 23 , and the other electrode connected to a ground line having a reference potential of vehicle power supply system 1 .

[0153] In the fourth setting at the time of failure, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the off state. On the other hand, the power supply from the first power supply 41 to the first load 11 is maintained by the switch SW1 in the on state. In addition, the first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the on state.

[0154] In the vehicle power supply system 1 of variant example 1, after an abnormality occurs in the second power supply 42 of the second power supply system 20, the capacitor 22 supplies power to the second load 21 to avoid a temporary interruption (also referred to as a momentary interruption) of power supplied to the second load 21 during the period from when the power from the first power supply system 10 is supplied to the second load 21 via the system connection part (connection line L60 and switch SW3).

[0155] According to the modification 1 described above, in addition to the effects obtained by the vehicle power supply system 1 of the embodiment (1), the following effects are obtained.

[0156] That is, in the vehicle power supply system 1 , the second power supply system 20 further includes the capacitor 22 capable of supplying power to the second load 21 during the transition time of the switch SW3 as the system connection portion from the disconnected state to the connected state.

[0157] Because of this structure, even if the power supply from the second power supply 42 to the second power supply system 20 is stopped due to an abnormality in the second power supply, power supply to the second load 21 will not be interrupted instantaneously, so the functions related to the execution of MRM can be stably maintained through the functions of the second load 21.

[0158] (Variant 2)

[0159] Emergency non-priority auxiliary machine load 117 included in first power supply system 10 in the embodiment may be excluded from first power supply system 10 and included as a third load in a newly-created third power supply system.

[0160] Figure 5 is a schematic diagram for explaining a vehicle power supply system 1 according to a second modification, and Figure 1 In the second variant, the setting performed in normal time is to set switches SW1, SW2, SW3, and SW4 to Figure 5 The switching state is illustrated in FIG.

[0161] In the second modification, the switching states of the switches SW1, SW2, SW3, and SW4 in the IG disconnection setting are as follows. That is, the first power supply 41 and the first load 11 are disconnected by the switch SW1 in the disconnected state. In addition, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the disconnected state. The first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the on state. In addition, the fourth power supply 82 described later and the third load 81 are connected by the switch SW4 in the on state.

[0162] Figure 5 The first power supply system 10 corresponds to Figure 1 The first power supply system 10. However, Figure 5The first power supply system 10 is similar to the first power supply system 10 in that the first power supply 41 supplies power at a voltage of DC 48 [V], the first load 11 operates at a voltage of DC 48 [V], the emergency non-priority auxiliary load 117 is omitted from the first load 11, and the first battery 12 outputs power at a voltage of DC 48 [V]. Figure 1 The first power supply system 10 is different.

[0163] Figure 5 The second power supply system 20, the high-voltage power supply system 30, and the connection line L60 and the switch SW3 as the system connection part correspond to Figure 1 The second power supply system 20, the high voltage power supply system 30, and the connection line L60 and the switch SW3 as the system connection part. However, Figure 5 The second power supply system 20 is similar to the second power supply system 20 in that the second power supply 42 supplies power at a voltage of 48 [V] DC and the second load 21 operates at a voltage of 48 [V] DC. Figure 1 The second power supply system 20 is different.

[0164] <Third power supply system>

[0165] The power supply system that supplies power to the third load 81 is referred to as a third power supply system 80. The third power supply system 80 includes a third power supply 43, a third load 81, and a fourth power supply 82, and the third power supply 43 and the third load 81 are connected by a power line L80.

[0166] (Third power source)

[0167] The third power supply 43 includes a DC-DC converter that converts a DC voltage (eg, 200 [V]) supplied from the high-voltage power supply system 30 into a voltage required by the third load 81. The third power supply 43 outputs a DC voltage (12 [V]) after the DC-DC conversion.

[0168] (Third load)

[0169] The third load 81 corresponds to Figure 1 The emergency non-priority auxiliary load 117 included in the first power supply system 10. In more detail, Figure 5 The headlight 817a, the wiper device 817b, the electric window device 817c, and the instrument 817d correspond to Figure 1 The third load 81 includes a headlamp 117a, a wiper device 117b, a power window device 117c, and instruments 117d. It should be noted that the third load 81 includes an ECU 811 for controlling each load.

[0170] (Fourth Power Source)

[0171] The fourth power supply 82 steps down the voltage of 48 V DC supplied from the first power supply system 10 to 12 V DC.

[0172] The fourth power supply 82 is connected to the first power supply system 10 via a power line L70. A diode 83 for preventing a reverse flow is inserted on the fourth power supply 82 side of the power line L70.

[0173] A switch SW4 is provided between the fourth power supply 82 and a contact point C81 provided on the power line L80. When the switch SW4 is on, the power output from the fourth power supply 82 is supplied to the third load 81. When the switch SW4 is off, the fourth power supply 82 is disconnected from the power line L80.

[0174] The switch SW4 is a normally closed (NC) switch composed of, for example, a semiconductor switch. The switch SW4 can switch between an on / off state when a switching control signal is input. Therefore, the switch SW4 is configured to switch between the fourth power supply 82 and the power line L80 by inputting a switching control signal to the switch SW4 in normal circumstances.

[0175] It should be noted that, for example, the switching of the switch SW4 is controlled by using the power from the third power supply 43 and the power from the fourth power supply 82. In other words, the ECU 811 that normally receives the power from the third power supply 43 of the third power supply system 80 performs the switching control of the switch SW4. On the other hand, when the ECU 811 that performs the switching control cannot receive the power supply from the third power supply 43, the switch SW4 is switched by another control device (not shown) that operates by receiving the power from the fourth power supply 82.

[0176] <Operation when the vehicle power system is abnormal>

[0177] Next, the operation of the vehicle power supply system 1 when an abnormality occurs in the vehicle power supply system 1, that is, when the operation is different from the normal state, will be described. Specifically, the switching control of the switches SW1, SW2, SW3, and SW4 will be described.

[0178] (High voltage fault)

[0179] Fig. 6A is a schematic diagram of a vehicle power supply system in the event of a high voltage fault. Switch SW1 and Figure 2A When the switching control signal is no longer input from the ECU 111 that detects the high voltage failure, the power line L10 between the first power source 41 and the first load 11 is disconnected. As described above, the switch SW1 is a normally open type switch.

[0180] Switch SW2 and Figure 2AWhen the switching control signal is no longer input from the ECU 211 that detects the high voltage failure, the power line L20 between the second power source 42 and the second load 21 is disconnected. As described above, the switch SW2 is a normally open switch.

[0181] Switch SW3 and Figure 2A When the switching control signal is no longer input from the ECU 111 or ECU 211 (or other control device that operates by receiving power from the high voltage power supply 31) that detects the high voltage failure, the connection line L60 between the first power supply system 10 and the second power supply system 20 is connected. As described above, the switch SW3 is a normally closed switch.

[0182] Even when the switch SW4 no longer receives a switching control signal from the ECU 811 that detects a high-voltage fault or cannot receive power from the third power supply 43 due to the high-voltage fault, the switch SW4 maintains the disconnection state between the fourth power supply 82 and the power line L80 by a switching control signal sent from another control device that operates by receiving power from the fourth power supply 82.

[0183] It should be noted that when the high-voltage fault is restored, the ECU811 that receives power from the third power supply 43 takes over the switching control of other control devices that operate by receiving power from the fourth power supply 82, and maintains the disconnected state of the switch SW4 (the disconnected state between the fourth power supply 82 and the power line L80).

[0184] In the second modification, the switches SW1, SW2, SW3, and SW4 are set to Fig. 6A The switching state illustrated in the example is called the first setting at the time of failure. In the first setting at the time of failure, the first power supply 41 and the first load 11 are disconnected by the switch SW1 in the disconnected state. In addition, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the disconnected state. In addition, the first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the conductive state. Furthermore, the fourth power supply 82 and the power line L80 are disconnected by the switch SW4 in the disconnected state.

[0185] Due to such a first fault setting, the first battery 12 connected to the power line L10 of the first power supply system 10 supplies the power required for the operation of the first load 11 to the first load 11, and supplies the power required for the operation of the second load 21 of the second power supply system 20 to the second load 21 via the connection line L60 serving as the system connection part and the switch SW3.

[0186] Because of this structure, even if the power supply from the high-voltage power supply system 30 to the first power supply system 10 and the second power supply system 20 is stopped due to a high-voltage failure, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the functions related to the execution of MRM are maintained by the functions of the first load 11 or the second load 21, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0187] It should be noted that in Fig. 6A The switching states of switches SW1, SW2, SW3, and SW4 illustrated in the figure can also be applied to a situation where, although 200 [V] of power is supplied from the high-voltage power supply system 30 to the first power supply 41 of the first power supply system 10 and the second power supply 42 of the second power supply system 20, some abnormality occurs in the first power supply 41 and the second power supply 42, and thus the 48 [V] voltage after DC-DC conversion cannot be output from the first power supply 41 and the second power supply 42.

[0188] (First load abnormality)

[0189] Figure 6B This is a schematic diagram of the vehicle power supply system for explaining an abnormality in the first load 11. A state in which the first load 11 of the first power supply system 10 is grounded or short-circuited due to some abnormality in the first load 11 is referred to as a first load abnormality (or Gr1 grounding).

[0190] Switch SW1 and Figure 2B When the switching control signal is no longer input from the ECU 111 that detects the abnormality of the first load, the power line L10 between the first power source 41 and the first load 11 is disconnected. As described above, the switch SW1 is a normally open switch.

[0191] Switch SW2 and Figure 2B When the switching control signal is continuously input from the ECU 211 (or other control device operated by receiving power from the high voltage power supply 31), the connection of the power line L20 between the second power supply 42 and the second load 21 is maintained. As described above, the switch SW2 is a normally open switch.

[0192] Switch SW3 and Figure 2B When the switching control signal is continuously input from ECU111 or ECU211 (or other control device operated by receiving power from high voltage power supply 31), the connection line L60 between the first power supply system 10 and the second power supply system 20 is maintained disconnected. As described above, switch SW3 is a normally closed switch.

[0193] The switch SW4 is a normally closed switch that maintains the disconnected state between the fourth power supply 82 and the power line L80 in accordance with a switching control signal issued from the ECU 811 that operates by receiving the power from the third power supply 43 .

[0194] In the second modification, the switches SW1, SW2, SW3, and SW4 are set to Figure 6B The switching state illustrated in the example is called the second setting at the time of failure. In the second setting at the time of failure, the power supply from the first power supply 41 to the first load 11 that has been grounded or short-circuited is disconnected by the switch SW1 in the disconnected state. On the other hand, the power supply from the second power supply 42 to the second load 21 is maintained by the switch SW2 in the conductive state. Furthermore, the disconnection between the first power supply system 10 and the second power supply system 20 is maintained by the switch SW3 in the disconnected state.

[0195] Because of this structure, even if the function of the first load 11 stops due to an abnormality in the first load, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the function related to the execution of MRM is maintained by the function of the second load 21, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0196] It should be noted that in Figure 6B The switching states of the switches SW1, SW2, SW3, and SW4 illustrated in the figure can also be applied to a situation where, although 200 [V] of power is supplied from the high-voltage power supply system 30 to the first power supply 41 of the first power supply system 10, due to some abnormality in the first power supply 41, the voltage of 48 [V] after DC-DC conversion cannot be output from the first power supply 41 (also referred to as a first power supply abnormality) and a situation where some abnormality occurs in the first battery 12 or in a charge and discharge control circuit not shown in the figure and arranged in parallel with the first battery 12 (also referred to as a first battery abnormality).

[0197] (Second load abnormality)

[0198] Figure 6C Schematic diagram of the vehicle power supply system for explaining an abnormality of the second load 21. A state in which the second load 21 is grounded or short-circuited due to an abnormality of some kind in the second load 21 of the second power supply system 20 is called a second load abnormality (or Gr2 grounding).

[0199] Switch SW1 and Figure 2C As in the case of , when the switching control signal continues to be input from the ECU 111, the connection of the power line L10 between the first power source 41 and the first load 11 is maintained. As described above, the switch SW1 is a normally open type switch.

[0200] Switch SW2 and Figure 2C When the switching control signal is no longer input from the ECU 211 (or other control device that operates by receiving power from the high-voltage power supply 31) that detects the abnormality of the second load, the power line L20 between the second power supply 42 and the second load 21 is disconnected. As described above, the switch SW2 is a normally open switch.

[0201] Switch SW3 and Figure 2C When the switching control signal is continuously input from ECU111 or ECU211 (or other control device operated by receiving power from high voltage power supply 31), the connection line L60 between the first power supply system 10 and the second power supply system 20 is maintained disconnected. As described above, switch SW3 is a normally closed switch.

[0202] The switch SW4 is a normally closed switch that maintains the disconnected state between the fourth power supply 82 and the power line L80 in accordance with a switching control signal issued from the ECU 811 that operates by receiving the power from the third power supply 43 .

[0203] In the second modification, the switches SW1, SW2, SW3, and SW4 are set to Figure 6C The switching state illustrated in the example is called the third setting at the time of failure. In the third setting at the time of failure, the power supply from the second power supply 42 to the second load 21 that has been grounded or short-circuited is disconnected by the switch SW2 in the disconnected state. On the other hand, the power supply from the first power supply 41 to the first load 11 is maintained by the switch SW1 in the on state. In addition, the disconnection between the first power supply system 10 and the second power supply system 20 is maintained by the switch SW3 in the disconnected state. In addition, the fourth power supply 82 and the power line L80 are disconnected by the switch SW4 in the disconnected state.

[0204] Because of this structure, even if the function of the second load 21 stops due to an abnormality in the second load, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the function related to the execution of MRM is maintained by the function of the first load 11, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0205] (Second power supply abnormality)

[0206] Fig.6D This is a schematic diagram for explaining the vehicle power supply system when the second power supply 42 is abnormal. The situation where the 48 [V] voltage after DC-DC conversion cannot be output from the second power supply 42 due to some abnormality in the second power supply system 20 is called second power supply abnormality.

[0207] Switch SW1 and Figure 2D As in the case of , when the switching control signal continues to be input from the ECU 111, the connection of the power line L10 between the first power source 41 and the first load 11 is maintained. As described above, the switch SW1 is a normally open type switch.

[0208] Switch SW2 and Figure 2D When the switching control signal is no longer input from the ECU 211 (or other control device that operates by receiving power from the high-voltage power supply 31) that detects the abnormality of the second power supply, the power line L20 between the second power supply 42 and the second load 21 is disconnected. As described above, the switch SW2 is a normally open switch.

[0209] Switch SW3 and Figure 2D When the switching control signal is no longer input from the ECU 111 or ECU 211 (or other control device that operates by receiving power from the high-voltage power supply 31) that detects the abnormality of the second power supply, the connection line L60 between the first power supply system 10 and the second power supply system 20 is connected. As described above, the switch SW3 is a normally closed switch.

[0210] The switch SW4 is a normally closed switch that maintains the disconnected state between the fourth power supply 82 and the power line L80 in accordance with a switching control signal issued from the ECU 811 that operates by receiving the power from the third power supply 43 .

[0211] In the second modification, the switches SW1, SW2, SW3, and SW4 are set to Fig.6D The switching state illustrated in the example is called the fourth setting at the time of failure. In the fourth setting at the time of failure, the second power supply 42 and the second load 21 are disconnected by the switch SW2 in the off state. On the other hand, the power supply from the first power supply 41 to the first load 11 is maintained by the switch SW1 in the on state. In addition, the first power supply system 10 and the second power supply system 20 are connected by the switch SW3 in the on state.

[0212] In addition, the first power supply 41 supplies the first load 11 with power required for the operation of the first load 11, and supplies the second load 21 with power required for the operation of the second load 21 of the second power supply system 20 via the connection line L60 as the system connection part and the switch SW3. In addition, the disconnection between the fourth power supply 82 and the power line L80 is maintained by the switch SW4 in the disconnected state.

[0213] Because of this structure, even if the power supply from the second power supply 42 to the second power supply system 20 is stopped due to an abnormality in the second power supply, it is possible to implement a redundant vehicle power supply system 1 in a manner in which the functions related to the execution of MRM are maintained by the functions of the first load 11, thereby further improving traffic safety. MRM is the minimum necessary driving operation, stopping operation, and driving control for safely moving the vehicle V to the shoulder of the road, etc. and stopping.

[0214] According to the second modification described above, in addition to the effects obtained by the vehicle power supply system 1 of the embodiment, the following effects are obtained.

[0215] (1) In the vehicle power supply system 1, the first power supply system 10 includes a first battery 12 capable of supplying power, and the vehicle power supply system 1 also includes: a third power supply system 80, which supplies power to a third load 81 that is not related to the driving control of the vehicle V; and a fourth power supply 82, which serves as a power supply unit and is arranged between the first power supply system 10 and the third power supply system 80, converts the power of the first power supply system 10 to generate power to be supplied to the third load 81.

[0216] Because of this configuration, even if a load not related to the driving control of the vehicle V is separated from the first load 11 as the third load 81 , the third load 81 can be operated using the power supplied from the first power supply system 10 without providing a new battery in the third power supply system 80 .

[0217] The vehicle power supply system 1 of the second modification can reduce the number of batteries compared to the case where the third power supply system 80 is also provided with batteries, and can contribute to the miniaturization and cost reduction of the system.

[0218] (2) In the vehicle power supply system 1 of (1) above, the fourth power supply 82 as the power supply unit converts the power from the first battery 12 to generate power to be supplied to the third load 81 .

[0219] Because of this configuration, there is no need to provide a new battery in the third power supply system 80, and the power supplied from the first battery 12 of the first power supply system 10 can be converted to generate the power required by the third load 81. For example, when the IG is disconnected, the power from the fourth power supply 82 is supplied to the third load 81 via the normally closed switch SW4.

[0220] The above description is merely an example, and the above embodiment and modified examples do not limit the present invention unless the features of the present invention are impaired. One or more of the above embodiment and modified examples can be arbitrarily combined, and the modified examples can be combined with each other.

[0221] According to the present invention, the number of batteries can be reduced without impairing the redundancy of the battery system.

[0222] The present invention has been described above in conjunction with preferred embodiments, but it should be understood by those skilled in the art that various modifications and changes can be made without departing from the scope of the claims.

Claims

1. A vehicle power supply system comprising a first power supply system (10) for supplying power from a first power supply (41) to a first load (11) related to driving control of a vehicle, and a second power supply system (20) for supplying power from a second power supply (42) to a second load (12) related to driving control of the vehicle, characterized in that: have: a system connection unit (SW3) capable of connecting and disconnecting the first power supply system (10) and the second power supply system (20); a second power connection portion (SW2) capable of connecting and disconnecting the second power source (42) and the second load (12); as well as A control unit switches the second power supply connection unit (SW2) from a connected state to a disconnected state and switches the system connection unit (SW3) from a disconnected state to a connected state when an abnormality of the second power supply is detected.

2. The vehicle power supply system according to claim 1, characterized in that: The control unit outputs a first control signal to the system connection unit (SW3) indicating connection or disconnection between the first power system (10) and the second power system (20), and outputs a second control signal to the second power connection unit (SW2) indicating connection or disconnection between the second power source (42) and the second load (12), The system connection unit (SW3) is configured to maintain the connection state when the first control signal is not input, The second power connection portion (SW2) is configured to maintain an open state when the second control signal is not input. The control unit stops outputting the first control signal and the second control signal when an abnormality of the second power supply is detected.

3. The vehicle power supply system according to claim 1, characterized in that: It also includes a first power supply connection unit (SW1) capable of connecting and disconnecting the first power supply (41) and the first load (11), The first power supply system (10) comprises a first battery (12) capable of supplying power to the first load (11). When the control unit detects an abnormality in the first power source (41), the control unit switches the first power source connection unit (SW1) from a connected state to a disconnected state.

4. The vehicle power supply system according to claim 3, characterized in that: The control unit outputs a third control signal to the first power connection unit (SW1) for instructing the first power source (41) to be connected or disconnected from the first load (11), The first power connection portion (SW1) is configured to maintain an open state when the third control signal is not input. When the control unit detects an abnormality in the first power supply (41), the control unit stops outputting the third control signal.

5. The vehicle power supply system according to claim 4, characterized in that: The first load (11) includes a first control device related to the steering operation or braking operation of the vehicle, The second load (12) includes a second control device related to driving assistance of the vehicle.

6. The vehicle power supply system according to claim 5, characterized in that: The first power source (41) and the second power source (42) respectively convert power from a second battery (31) that supplies driving power to the vehicle to generate power to be supplied to the first load (41) and the second load (42).

7. The vehicle power supply system according to claim 6, characterized in that: The system connection unit (SW3) is operated by power supplied from the second battery (31) and one of the first power supply system (10) or the second power supply system (20), The second power connection unit (SW2) is operated by power supplied from one of the second battery (31) and the second power supply system (20).

8. The vehicle power supply system according to claim 1, characterized in that: The second power supply system (20) further includes a capacitor (22) capable of supplying power to the second load (12) during a transition time from a disconnected state to a connected state of the system connection portion (SW3).

9. The vehicle power supply system according to claim 1, characterized in that: The first power supply system (10) comprises a first battery (12) capable of supplying power to the first load (11). The vehicle power supply system further comprises: a third power supply system (80) for supplying electric power to a third load (81) having no relation to driving control of the vehicle and having a driving voltage different from that of the first load (11); as well as A power supply unit (82) is provided between the first power supply system (10) and the third power supply system (80), and converts the power of the first power supply system (10) to generate power to be supplied to the third load (81).

10. The vehicle power supply system according to claim 9, characterized in that: The power supply unit (82) steps down the voltage from the first battery (12) to generate power to be supplied to the third load (81) having a lower driving voltage than the first load (11).

Images