Control device

Abstract

To provide a control device capable of supplying power from an auxiliary power system to an electric brake device when a main power system fails while suppressing power taken out from the auxiliary power system.SOLUTION: A control device controls a system comprising a first power supply system that supplies power to an electric brake device mounted on a vehicle, and a second power supply system that supplies power to the electric brake device when the first power supply system fails. When the vehicle is not performing an automatic parking function, an output voltage of the second power supply system is set to a first voltage, and when the vehicle is performing the automatic parking function, the output voltage of the second power supply system is set to a second voltage higher than the first voltage. If an abnormality occurs in the first power supply system while the vehicle is performing the automatic parking function, the output voltage of the second power supply system is set to the third voltage, which is higher than the second voltage. The second voltage is lower than the output voltage of the first power supply system and is a voltage at which the electric brake device can operate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a control device for a backup power supply system mounted on a vehicle.

Background Art

[0002] Patent Document 1 discloses a control device that, when the main power supply system fails during execution of the automatic parking function in a vehicle, supplies power to the electric brake device by an auxiliary power supply system to promptly brake and stop the vehicle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to stably supply power from the auxiliary power supply system to the electric brake device, it is conceivable to increase the capacity of the storage battery in the auxiliary power supply system, but the cost and weight increase. Also, it is conceivable to increase the charging voltage of the storage battery, but the life of the storage battery deteriorates. Further, it is conceivable to set the target output voltage of the auxiliary power supply system high in advance, but while the automatic parking function is not being executed, the output voltage of the auxiliary power supply system is always higher than the output voltage of the main power supply system, resulting in power being drawn from the auxiliary power supply system. Therefore, there is room for further consideration in the control of the auxiliary power supply system when the main power supply system fails during execution of the automatic parking function.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a control device that can supply power from an auxiliary power supply system to an electric brake device when the main power supply system fails while suppressing power draw from the auxiliary power supply system.

Means for Solving the Problems

[0006] One aspect of the disclosed technology for solving the above problems is a control device that controls a system including a first power supply system that supplies power to an electric brake device mounted on a vehicle and a second power supply system that supplies power to the electric brake device in the event of a failure of the first power supply system. When the vehicle is not executing the automatic parking function, the output voltage of the second power supply system is set to a first voltage. When the vehicle is executing the automatic parking function, the output voltage of the second power supply system is set to a second voltage higher than the first voltage. When an abnormality occurs in the first power supply system while the vehicle is executing the automatic parking function, the output voltage of the second power supply system is set to a third voltage higher than the second voltage. The second voltage is lower than the output voltage of the first power supply system and is a voltage at which the electric brake device can operate.

Advantages of the Invention

[0007] According to the control device of the present disclosure, power can be supplied from the second power supply system to the electric brake device in the event of a failure of the first power supply system while suppressing the extraction of power from the second power supply system.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0009] [First Embodiment] <Configuration> FIG. 1 is a schematic configuration diagram of a system including a control device 10 according to a first embodiment of the present disclosure and its peripheral parts. The system of the first embodiment illustrated in FIG. 1 includes a control device 10, a first power supply system 20, a second power supply system 30, an electric brake device 41, and an automatic parking control device 100. This system is mounted on vehicles such as, for example, an internal combustion engine vehicle, a hybrid electric vehicle (HEV), and a battery electric vehicle (BEV). In FIG. 1, power lines are indicated by solid lines and control signal lines are indicated by broken lines.

[0010] (Electric Brake Device) The electric brake device 41 is a device that brakes the vehicle based on a command from the automatic parking control device 100. The electric brake device 41 includes a brake actuator and a control unit that controls the brake actuator by an electrical control signal corresponding to a command from the automatic parking control device 100. The electric brake device 41 can receive power supply from the first power supply system 20 and the second power supply system 30.

[0011] (First Power Supply System) The first power supply system 20 is a main power supply system (auxiliary machine power supply, etc.) that supplies power to the electric brake device 41. The first power supply system 20 includes, as an example, a first battery 21, a second battery 23, and a first DC-DC converter (first DDC) 22 provided between them.

[0012] The first battery 21 is, for example, a lithium-ion battery charged by supply power from outside the vehicle or generated power by a generator (not shown) provided in the vehicle. The second battery 23 is, for example, a lead-acid battery having an output voltage lower than that of the first battery 21. The first DC-DC converter 22 transforms the output of the first battery 21 to a predetermined voltage. The output from the first DC-DC converter 22 and the output of the second battery 23 become the output of the first power supply system 20. Also, the output of the first DC-DC converter 22 is used for charging the second battery 23. The first power supply system 20 may also supply power to the control device 10, the automatic parking control device 100, and the like.

[0013] (Second power supply system) The second power supply system 30 is an auxiliary power supply system (such as a backup power supply) that supplies power to the electric brake device 41 as an auxiliary. The second power supply system 30 includes a second DC-DC converter (second DDC) 31, a capacitor 32 connected to the second DC-DC converter 31, and a first relay 33. The first relay 33 is provided so that it can short-circuit between the terminals of the capacitor 32 in the closed state to form a discharge path for the capacitor 32. The capacitor 32 is the power source of the second power supply system 30.

[0014] The second DC-DC converter 31 is a DC-DC converter capable of bidirectional voltage conversion output. Specifically, the second DC-DC converter 31 transforms the output of the capacitor 32 to a target output voltage described later to obtain the output of the second power supply system 30. Also, the second DC-DC converter 31 transforms the output of the first power supply system 20 supplied via a second relay 80 provided between the first power supply system 20 and the second power supply system 30 to a predetermined voltage and supplies it to the capacitor 32 to charge the capacitor 32.

[0015] A first rectifying element (diode) 50 is provided between the first power supply system 20 and the electric brake device 41. One end of the first rectifying element 50 connected to the first power supply system 20 side is the inflow side, and the other end connected to the electric brake device 41 side is the outflow side.

[0016] A third relay 71 and a second rectifying element (diode) 61 are provided in series between the second power supply system 30 and the electric brake device 41. One end of the second rectifying element 61 connected to the second power supply system 30 side is the inflow side, and the other end connected to the electric brake device 41 side is the outflow side.

[0017] (Control device) The control device 10 controls the power supply from the second power supply system 30 to the electric brake device 41. The control device 10 includes a fault detection unit 11 and a power supply system control unit 12. The control device 10 is typically an electronic control unit (ECU: Electronic Control Unit) including a processor, a memory, an input / output interface, and the like.

[0018] The fault detection unit 11 detects the presence or absence of a fault, which is one of the abnormal states in the first power supply system 20. The method for detecting a fault by the fault detection unit 11 is not particularly limited. In this embodiment, as an example, a fault is detected based on the output voltage of the first power supply system 20 measured by a voltage sensor (not shown).

[0019] The power supply system control unit 12 can acquire information indicating the execution state of the automatic parking function from the automatic parking control device 100. Also, the power supply system control unit 12 can acquire the detection result of a fault in the first power supply system 20 from the fault detection unit 11. Based on the execution state of the automatic parking function and the detection result of a fault in the first power supply system 20, the power supply system control unit 12 controls the first relay 33, the second relay 80, the third relay 71, and the second DC-DC converter 31 of the second power supply system 30, thereby setting the output voltage (target output voltage) of the second power supply system 30 and supplying backup power to the electric brake device 41.

[0020] (Automatic Parking Control Device) The automatic parking control device 100 is provided in the vehicle to realize the automatic parking function. When receiving a parking instruction from the user, the automatic parking control device 100 generates a command for controlling the driving force, braking force, steering angle, etc. of the vehicle based on information such as the vehicle and the information around the vehicle measured by various sensors provided in the vehicle, and outputs it to the control device of the engine or motor provided in the vehicle, the electric brake device 41, the steering control device, etc., to control the vehicle so that it can automatically park in a parking space.

[0021] Note that the mode of the automatic parking function realized by the automatic parking control device 100 is not limited. The mode of the automatic parking function includes, for example, a mode of parking in a parking space upon receiving an instruction from a user sitting in the driver's seat near the parking space, a remote parking mode of parking in a parking space upon receiving an instruction from a user who has gotten out of the vehicle near the parking space, an automatic valet parking mode of moving from the entrance of a parking lot to a parking space and parking in the parking space upon receiving an instruction from a user who has gotten out of the vehicle at the entrance of the parking lot, and the like.

[0022] <Control> Next, with further reference to FIG. 2, the control of the power supply system performed by the control device 10 during the execution of the automatic parking function will be described. FIG. 2 is a flowchart showing the processing procedure of the output voltage setting control of the second power supply system 30 executed by the control device 10 according to the first embodiment. The output voltage setting control illustrated in FIG. 2 is started when the charging of the integrated backup power supply is completed.

[0023] (Step S201) The power supply system control unit 12 sets the output voltage (target output voltage) of the second power supply system 30 to the first voltage V1. The first voltage V1 is a specified value and can be, for example, 10V. This setting of the output voltage can be performed by issuing a command (voltage indication value) corresponding to the output voltage to the second DC-DC converter 31. When the output voltage of the second power supply system 30 is set to the first voltage V1, the process proceeds to step S202.

[0024] (Step S202) The power supply system control unit 12 determines whether the automatic parking control device 100 has received a parking instruction from the user and is executing the automatic parking function. If the automatic parking function is being executed (step S202, Yes), the process proceeds to step S203. On the other hand, if the automatic parking function is not being executed (step S202, No), this output voltage setting control ends.

[0025] (Step S203) The power supply system control unit 12 sets the output voltage (target output voltage) of the second power supply system 30 to the second voltage V2. The second voltage V2 is a specified value higher than the first voltage V1 (V2 > V1), and can be, for example, 11V. This second voltage V2 is lower than the output voltage of the first power supply system 20 and is a voltage at which the electric brake device 41 can operate. When the output voltage of the second power supply system 30 is set to the second voltage V2, the process proceeds to step S204.

[0026] (Step S204) The fault detection unit 11 determines whether an abnormality such as a fault has occurred in the first power supply system 20. If an abnormality has occurred in the first power supply system 20 (step S204, yes), the process proceeds to step S205. On the other hand, if no abnormality has occurred in the first power supply system 20 (step S204, no), the process proceeds to step S207.

[0027] (Step S205) The power supply system control unit 12 of the control device 10 sets the output voltage (target output voltage) of the second power supply system 30 to the third voltage V3. The third voltage V3 is a specified value higher than the second voltage V2 (V3 > V2), and can be, for example, 12V. When the output voltage of the second power supply system 30 is set to the third voltage V3, the process proceeds to step S206.

[0028] (Step S206) The power supply system control unit 12 controls the second relay 80 and the third relay 71 to perform backup power supply for supplying power from the second power supply system 30 to the electric brake device 41. When backup power supply is provided to the electric brake device 41, this output voltage setting control ends.

[0029] (Step S207) The power supply system control unit 12 of the control device 10 determines whether the automatic parking function by the automatic parking control device 100 has been completed. If the automatic parking function has been completed (step S207, yes), this output voltage setting control ends. On the other hand, if the automatic parking function has not been completed (step S207, no), the process proceeds to step S204.

[0030] With the output voltage setting control of the first embodiment, even when the detection of a fault in the first power supply system 20 by the fault detection unit 11 is delayed, power can be supplied from the second power supply system 30 to the electric brake device 41. Therefore, it is possible to suppress the consumption of the cell capacity, prevent an increase in cost due to an increase in capacity or a complication of control, and achieve miniaturization.

[0031] [Second Embodiment] [Configuration] FIG. 3 is a schematic configuration diagram of a system including the control device 10 according to the second embodiment of the present disclosure and its peripheral parts. The system of the second embodiment illustrated in FIG. 3 has an additional configuration of a shift-by-wire (SBW) 42, a third rectifying element 62, and a fourth relay 72 compared to the system of the first embodiment illustrated in FIG. 1.

[0032] [Shift-by-Wire] The shift-by-wire (SBW) 42 is a device that can change the gear stage of a transmission (not shown) by an electric signal. The shift-by-wire (SBW) 42 includes a control unit that converts the driver's shift operation into an electrical control signal, and an actuator that changes the gear stage based on the control signal instructed by the control unit. The shift-by-wire (SBW) 42 can receive power supply from the first power supply system 20 and the second power supply system 30.

[0033] The second power supply system 30 is an auxiliary power supply system (such as a backup power supply) that supplies power to the electric brake device 41 and the shift-by-wire (SBW) 42. A fourth relay 72 and a third rectifying element (diode) 62 are provided in series between the second power supply system 30 and the shift-by-wire (SBW) 42. One end of the third rectifying element 62 connected to the second power supply system 30 side is the inflow side, and the other end connected to the shift-by-wire (SBW) 42 side is the outflow side.

[0034] In addition to controlling the power supply from the second power supply system 30 to the electric brake device 41, the control device 10 controls the power supply from the second power supply system 30 to the shift-by-wire (SBW) 42. Based on the execution state of the automatic parking function and the detection result of a fault in the first power supply system 20, the power supply system control unit 12 controls the first relay 33, the second relay 80, the third relay 71, the fourth relay 72, and the second DC-DC converter 31 of the second power supply system 30 to set the output voltage (target output voltage) of the second power supply system 30 and supply backup power to the electric brake device 41 and the shift-by-wire (SBW) 42.

[0035] When the automatic parking control device 100 receives a parking instruction from the user, it generates commands to control the driving force, braking force, steering angle, etc. of the vehicle based on information such as the vehicle and its surroundings measured by various sensors equipped on the vehicle, and outputs them to the control device of the engine or motor equipped on the vehicle, the electric brake device 41, the shift-by-wire (SBW) 42, the steering control device, etc., to control the vehicle so that it can automatically park in a parking space.

[0036] <Control> FIG. 4 is a flowchart showing the processing procedure of the voltage setting control of the second power supply system 30 executed by the control device 10 according to the second embodiment. The processing in steps S201 to S204 and S207 in FIG. 4 is the same as the processing in FIG. 2.

[0037] (Step S401) If it is determined in step S204 that an abnormality has occurred in the first power supply system 20, the power supply system control unit 12 controls the second relay 80 and the third relay 71 to perform backup power supply for supplying power from the second power supply system 30 to the electric brake device 41. When backup power supply is provided to the electric brake device 41, the processing proceeds to step S402.

[0038] (Step S402) The power supply system control unit 12 sets the output voltage (target output voltage) of the second power supply system 30 to the third voltage V3. The third voltage V3 is a specified value higher than the second voltage V2 (V3 > V2), and can be, for example, 12V. When the output voltage of the second power supply system 30 is set to the third voltage V3, the process proceeds to step S403.

[0039] (Step S403) The power supply system control unit 12 controls the second relay 80 and the fourth relay 72 to perform backup power supply that supplies power from the second power supply system 30 to the shift-by-wire (SBW) 42. When backup power supply is provided to the shift-by-wire (SBW) 42, this output voltage setting control ends.

[0040] By the output voltage setting control of this second embodiment, when a failure of the first power supply system 20 is detected by the failure detection unit 11, vehicle fixing by the shift-by-wire (SBW) 42 can be performed after controlling the electric brake device 41. Therefore, consumption of the cell capacity can be suppressed, cost increase due to capacity increase or control complexity can be prevented, and miniaturization becomes possible.

[0041] [Third Embodiment] [Configuration] FIG. 5 is a schematic configuration diagram of a system including the control device 10 according to the third embodiment of the present disclosure and its peripheral parts. The system of the third embodiment illustrated in FIG. 5 has an additional configuration of a fifth relay 34 compared to the system of the first embodiment illustrated in FIG. 1.

[0042] (Second Power Supply System) The second power supply system 30 is an auxiliary power supply system (such as a backup power supply) that supplies power to the electric brake device 41. The second power supply system 30 includes a second DC-DC converter (second DDC) 31, a capacitor 32 connected to the second DC-DC converter 31, a first relay 33, and a fifth relay 34. The first relay 33 is provided so as to be able to short-circuit between the terminals of the capacitor 32 in the closed state to form a discharge path for the capacitor 32. The fifth relay 34 is provided between the second DC-DC converter 31 and the connection point of the second relay 80 and the third relay 71. The capacitor 32 is the power source of the second power supply system 30.

[0043] The second DC-DC converter 31 is a DC-DC converter capable of voltage conversion output in both directions. Specifically, the second DC-DC converter 31 transforms the output of the capacitor 32 to a target output voltage described later and outputs it as the output of the second power supply system 30. Also, the second DC-DC converter 31 transforms the output of the first power supply system 20 supplied via the second relay 80 and the fifth relay 34 provided between the first power supply system 20 and the second power supply system 30 to a predetermined voltage and supplies it to the capacitor 32 to charge the capacitor 32.

[0044] (Control device) The power supply system control unit 12 can acquire information indicating the execution state of the automatic parking function from the automatic parking control device 100. Also, the power supply system control unit 12 can acquire the detection result of a fault in the first power supply system 20 from the fault detection unit 11. Based on the execution state of the automatic parking function and the detection result of a fault in the first power supply system 20, the power supply system control unit 12 controls the first relay 33, the second relay 80, the third relay 71, the fifth relay 34, and the second DC-DC converter 31 of the second power supply system 30, thereby setting the output voltage (target output voltage) of the second power supply system 30 and supplying backup power to the electric brake device 41.

[0045] <Control> FIG. 6 is a flowchart showing the processing procedure of voltage setting control for the second power supply system 30 executed by the control device 10 according to the third embodiment. In FIG. 6, the processing of steps S202, S204, and S206 to S207 is the same as the processing of FIG. 2.

[0046] (Step S601) The power supply system control unit 12 sets the output voltage (target output voltage) of the second DC-DC converter 31 to the first voltage V1 and sets the fifth relay 34 to the OFF state (open state). The first voltage V1 is a specified value and can be, for example, 10V. This setting of the output voltage can be performed by issuing a command (voltage indication value) corresponding to the output voltage to the second DC-DC converter 31. When the output voltage of the second DC-DC converter 31 is set to the first voltage V1 and the fifth relay 34 is set to the OFF state, the process proceeds to step S202.

[0047] (Step S202) The power supply system control unit 12 determines whether the automatic parking control device 100 has received a parking instruction from the user and is executing the automatic parking function. If the automatic parking function is being executed (step S202, yes), the process proceeds to step S602. On the other hand, if the automatic parking function is not being executed (step S202, no), this output voltage setting control ends.

[0048] (Step S602) The power supply system control unit 12 sets the output voltage (target output voltage) of the second DC-DC converter 31 to the second voltage V2 and sets the fifth relay 34 to the ON state (closed state). The second voltage V2 is a specified value higher than the first voltage V1 (V2 > V1) and can be, for example, 11V. This second voltage V2 is lower than the output voltage of the first power supply system 20 and is a voltage at which the electric brake device 41 can operate. When the output voltage of the second DC-DC converter 31 is set to the second voltage V2 and the fifth relay 34 is set to the ON state, the process proceeds to step S204.

[0049] (Step S204) The failure detection unit 11 determines whether an abnormality such as a failure has occurred in the first power supply system 20. If an abnormality has occurred in the first power supply system 20 (step S204, yes), the process proceeds to step S603. On the other hand, if no abnormality has occurred in the first power supply system 20 (step S204, no), the process proceeds to step S207.

[0050] (Step S603) The power supply system control unit 12 of the control device 10 sets the output voltage (target output voltage) of the second power supply system 30 to the third voltage V3 and sets the fifth relay 34 to the ON state (closed state). The third voltage V3 is a specified value higher than the second voltage V2 (V3 > V2) and can be, for example, 12V. When the output voltage of the second power supply system 30 is set to the third voltage V3 and the fifth relay 34 is set to the ON state, the process proceeds to step S206.

[0051] By the output voltage setting control of this third embodiment, when the automatic parking is not being executed, if the fifth relay 34 is simply turned ON, power that can operate the electric brake device 41 can be immediately supplied from the second power supply system 30. Therefore, the extraction of power from the capacitor 32 can be suppressed.

[0052] <Function and Effect> As described above, according to the control device 10 according to an embodiment of the present disclosure, even if the first power supply system 20 fails during the execution of the automatic parking (remote parking) function, the second power supply system 30 can maintain the operation of the electric brake device 41 and the shift-by-wire (SBW) 42. Therefore, the vehicle can be promptly braked and safely stopped.

[0053] Also, during the execution of the automatic parking function, by setting the output voltage of the second power supply system 30 to be lower than the output voltage of the first power supply system 20 and to a voltage value at which the electric brake device 41 can operate, while suppressing the extraction of power from the second power supply system 30, power can be supplied from the second power supply system 30 to the electric brake device 41 etc. when the first power supply system 20 fails.

[0054] In addition, in order to avoid voltage extraction from the second power supply system 30 when a voltage drop occurs in the first power supply system 20 during the execution of the automatic parking function, power supply from the first power supply system 20 to unnecessary functions such as lights, wipers, and defoggers may be cut off during the execution of the automatic parking function.

Industrial Applicability

[0055] The control device of the present disclosure can be used for controlling a backup power supply system for vehicles and the like.

Explanation of Reference Numerals

[0056] 10 Control device 11 Fault detection unit 12 Power supply system control unit 20 First power supply system 21, 23 Battery 22, 31 DCDC converter (DDC) 30 Second power supply system 32 Capacitor 33, 34, 71, 72, 80 Relay 41 Electric brake device 42 Shift-by-wire (SBW) 50, 61, 62 Rectifying element 100 Automatic parking control device

Claims

【Claim 1】 A control device for controlling a system comprising a first power supply system that supplies power to an electric brake device mounted on a vehicle and a second power supply system that supplies power to the electric brake device when the first power supply system fails, wherein: when the vehicle is not executing the automatic parking function, the output voltage of the second power supply system is set to a first voltage; when the vehicle is executing the automatic parking function, the output voltage of the second power supply system is set to a second voltage higher than the first voltage; when an abnormality occurs in the first power supply system while the vehicle is executing the automatic parking function, the output voltage of the second power supply system is set to a third voltage higher than the second voltage; the second voltage is lower than the output voltage of the first power supply system and is a voltage at which the electric brake device can operate.

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