Control device, control method, and control program

Abstract

To provide a control device and the like capable of effectively utilizing battery power in a secondary power supply system.SOLUTION: A control device that controls a power supply from a battery to a predetermined load via an electric circuit includes: an acquisition unit that acquires a battery status; and a startup control unit capable of transmitting the status of starting and stopping the control device and controlling the electric circuit based on the status of the battery acquired by the acquisition unit. When the battery is in the status where it is possible to supply the power to a predetermined load after starting the control device, the startup control unit controls maintaining an electrical connection between the battery and the predetermined load and stops one part of the functions of the control device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a control device that controls power supply from a battery to a predetermined load or the like. [Background technology]

[0002] Patent Document 1 discloses a configuration in which a power supply configuration is provided independently for a primary power supply system and a secondary power supply system in order to increase the reliability of the power supply of the vehicle platform in an autonomous driving vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-123145 Summary of the Invention [Problem to be solved by the invention]

[0004] A vehicle equipped with an automatic driving system such as that described in Patent Document 1 has a problem in that when the automatic driving function is not used, such as when the vehicle is parked, the electric power (energy) is simply stored in the battery of the secondary power supply system, and the electric power is not effectively utilized. To address this problem, a method of supplying the electric power of the battery of the secondary power supply system to the load of the primary power supply system while the vehicle is parked is considered, but there is room for further study in order to suppress losses related to the supply and effectively utilize the electric power.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and has an object to provide a control device and the like that can effectively utilize the power of a battery in a secondary power supply system. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the disclosed technology is a control device that controls the supply of power from a battery to a specified load via an electric circuit, and includes an acquisition unit that acquires the state of the battery, and a startup control unit that is capable of transitioning between starting and stopping the control device and controls the electric circuit based on the state of the battery acquired by the acquisition unit, and when the state of the battery is such that power can be supplied to the specified load after the control device is started, the startup control unit controls the electric circuit to maintain an electrical connection between the battery and the specified load, and stops some of the functions of the control device. Effect of the Invention

[0007] According to the control device disclosed herein, when power is supplied from a battery of a secondary power system to a load of a primary power system, the electrical circuit between the battery and the load is kept electrically connected to the battery while some of the functions of the control device are stopped, thereby enabling effective use of the battery power. [Brief description of the drawings]

[0008] [Figure 1] A functional block diagram of a multi-battery system including a control device according to a first embodiment of the present disclosure and its peripheral parts. [Figure 2A] 1 is a flowchart showing a process of power supply control performed by a control device according to a first embodiment; [Figure 2B] 1 is a flowchart showing a process of power supply control performed by a control device according to a first embodiment; [Diagram 3] FIG. 1 is an operation timing diagram of each component in power supply control performed by a control device according to a first embodiment; [Figure 4] A functional block diagram of a multi-battery system including a control device according to a second embodiment of the present disclosure and its peripheral parts. [Figure 5A] 11 is a flowchart showing a process of power supply control performed by a control device according to a second embodiment. [Figure 5B] 11 is a flowchart showing a process of power supply control performed by a control device according to a second embodiment. [Figure 5C]11 is a flowchart showing a process of power supply control performed by a control device according to a second embodiment. [Figure 6] FIG. 11 is an operation timing diagram of each component in the power supply control performed by the control device according to the second embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The control device of the present disclosure latches up an electric circuit provided between a load and a battery so that the load and the battery can be maintained in an electrically connected state. When the battery has available power to supply, the latch-up is activated to maintain the state in which power is supplied from the battery to the load, while the control device is placed in a sleep state in which power consumption is low, thereby suppressing a decrease in the available power to be supplied from the battery to the load and making effective use of power. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0010] <First embodiment> [composition] Fig. 1 is a functional block diagram of a multi-battery system 100 including a control device 110 according to a first embodiment of the present disclosure and its peripheral parts. The functional blocks illustrated in Fig. 1 include the multi-battery system 100, a first battery 410, an electronic system 420, and a plurality of loads 310, 320, and 330. These configurations can be mounted on, for example, a vehicle.

[0011] The first battery 410 is a power supply source (primary power supply system) that supplies power to the electronic system 420 and the multiple loads 310, 320, and 330. The first battery 410 is, for example, a secondary battery such as a lithium ion battery that is configured to be chargeable and dischargeable. In the case of a vehicle, the first battery 410 can be, for example, an auxiliary battery used to supply power to on-board devices that are not involved in driving the vehicle.

[0012] The electronic system 420 is a predetermined device (load) that is driven by receiving power from the first battery 410. If the electronic system 420 is a vehicle, it can be exemplified by on-board devices (such as an air conditioner and lighting devices) that are not involved in driving the vehicle. The number of electronic systems 420 is not limited to that shown in FIG.

[0013] The multiple loads 310, 320, and 330 are predetermined devices that are driven by power supplied from the first battery 410, which is a primary power supply system, and from the multi-battery system 100, which is a secondary power supply system. The number of the multiple loads 310, 320, and 330 is not limited to that shown in Fig. 1. Examples of the multiple loads 310, 320, and 330 include loads to be backed up that require a redundant power supply configuration using the multi-battery system 100 (for example, an automatic driving system for a vehicle).

[0014] The multi-battery system 100 is a power supply system (secondary power supply system) for supplying backup power to the multiple loads 310, 320, and 330 in place of the first battery 410 when an abnormality occurs in the power supply from the first battery 410 to the multiple loads 310, 320, and 330 due to a power failure of the first battery 410 or the like. The multi-battery system 100 illustrated in FIG. 1 includes a control device 110, a second battery 120, a DC-DC converter 130, a monitoring circuit 140, a latch circuit 150, and multiple relays 161 to 165.

[0015] The second battery 120 is, for example, a secondary battery such as a lithium ion battery configured to be chargeable and dischargeable, or a capacitor. The second battery 120 is connected to the DCDC converter 130 and the relay 161 so as to be able to charge the power of the first battery 410 and to be able to discharge the power stored in the second battery 120 to the first battery 410 and the electronic system 420. The second battery 120 is also connected to a plurality of loads 310, 320, and 330 via the relays 161, 163 to 165 so as to be able to supply the power stored in the second battery 120. The second battery 120 is a power source that supplies power for operating (activating) the control device 110, the DCDC converter 130, the monitoring circuit 140, the latch circuit 150, and the plurality of relays 161 to 165.

[0016] The DCDC converter 130 is configured to input the power of the first battery 410, convert it to a power of a predetermined voltage, and output it to the second battery 120, or input the power of the second battery 120, convert it to a power of a predetermined voltage, and output it to the first battery 410 or the electronic system 420, based on an instruction from the control device 110 or another electronic control device (ECU) (not shown). This DCDC converter 130 constitutes a part of an electric circuit that connects the first battery 410 and the electronic system 420 (primary power supply system) to the second battery 120 (secondary power supply system).

[0017] The monitoring circuit 140 is configured to monitor the state of the second battery 120. Examples of the state of the second battery 120 include physical quantities such as voltage, current, and temperature. The monitoring circuit 140 may be configured only with a detection element such as a sensor that measures the physical quantity, or may be configured as an integrated circuit (IC) that further includes a processor and memory that calculates the value detected by the detection element.

[0018] The relay 161 is a switch element that can switch an electrical connection between the DCDC converter 130 and the second battery 120. The relay 161 is provided to switch an electrical connection between the DCDC converter 130 and the second battery 120, and is inserted between the DCDC converter 130 and the second battery 120 in the example of FIG. 1. The relay 161 may be inserted between the second battery 120 and ground (GND). The relay 161 may be an excitation type mechanical relay or a semiconductor relay using a field effect transistor (e.g., MOSFET). The relay 161 constitutes a part of an electric circuit that connects the first battery 410 and the electronic system 420 (primary power supply system) to the second battery 120 (secondary power supply system).

[0019] The latch circuit 150 is configured to hold the operation state of the DCDC converter 130 and the operation state of the relay 161 based on an instruction from the control device 110. More specifically, when a predetermined instruction is given from the control device 110 in response to the reception of a power supply instruction, the latch circuit 150 latches up the DCDC converter 130 in a chargeable / dischargeable operation state and latches up the relay 161 in a conductive state so as to hold at least an electrically connected state between the second battery 120, the first battery 410, and the electronic system 420. This latch-up control maintains a state in which power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420 (or a plurality of loads 310, 320, and 330). Note that a well-known circuit configuration can be used for the latch circuit 150.

[0020] The multiple relays 162 to 165 are switch elements that can switch between an electrical conductive / cut-off state based on an instruction from the control device 110 or another electronic control device (ECU) (not shown). The relay 162 is inserted between the first battery 410 and the multiple loads 310, 320, and 330. The relay 163 is inserted between the relay 161 and the relay 162. The relay 164 is inserted between the relay 162 and the load 320. The relay 165 is inserted between the relay 162 and the load 330. The number of the multiple relays 164 and 165 that connect the loads 320 and 330 to the multi-battery system 100 is not limited to that shown in FIG. 1, and increases or decreases according to the number of loads connected to the multi-battery system 100.

[0021] The control device 110 is configured to control the monitoring circuit 140 and the latch circuit 150 to effectively utilize the power of the second battery 120. The control device 110 has a function (acquisition unit) of acquiring the state of the second battery 120 via the monitoring circuit 140. The control device 110 also has a function (acquisition unit) of accepting a predetermined power supply request from the outside of the multi-battery system 100. For example, in the case of a vehicle, this power supply request is transmitted at the start of a service from a load (for example, the electronic system 420) that consumes power from the first battery 410 while the vehicle is parked. The control device 110 has a function (start-up control unit) of instructing the latch circuit 150 based on the state of the second battery 120 and appropriately controlling the DCDC converter 130 and the relay 161 when there is a power supply request. Furthermore, the control device 110 has a function (start-up control unit) capable of suitably transitioning between a wake-up state in which all functions are activated, and a sleep state in which only some functions (for example, a function for accepting a power supply request) are activated and the remaining functions are stopped in order to reduce power consumption. This function (start-up control unit) can also instruct the monitoring circuit 140 to transition between a wake-up state in which all functions are activated, and a sleep state in which all functions are stopped. The detailed control of the control device 110 will be described later.

[0022] A part or all of the configuration of the control device 110 can be typically configured as a microcomputer including a processor, a memory, an input / output interface, etc. This microcomputer can realize a part or all of the various functions described above by the processor reading and executing a program stored in the memory.

[0023] [control] Next, with further reference to Fig. 2A, Fig. 2B, and Fig. 3, the control performed by the control device 110 according to the first embodiment when the multi-battery system 100 is mounted on a vehicle will be described. Fig. 2A and Fig. 2B are flowcharts explaining the processing procedure of the power supply control performed by the control device 110. The processing of Fig. 2A and the processing of Fig. 2B are connected by connectors V and W. Fig. 3 is a timing chart of the power supply control performed by the control device 110 according to the first embodiment.

[0024] 2A and 2B is started when a predetermined state occurs in which there is no possibility of using the power of the second battery 120 provided redundantly as a backup power source, such as when the vehicle ignition is turned off (IG-OFF), and is repeatedly performed until the predetermined state is released. Note that when the power supply control is started, both the control device 110 and the monitoring circuit 140 are in a sleep state.

[0025] (Step S201) The control device 110 determines whether or not there is a power supply request in a sleep state in which some functions (e.g., functions other than the reception unit) are stopped. This power supply request is transmitted and received using an in-vehicle network such as a CAN. If the control device 110 determines that there is a power supply request (step S201, Yes), the process proceeds to step S202.

[0026] (Step S202) The control device 110 transitions from a sleep state to a wake-up state in which all functions are activated. The control device 110 also transitions the monitoring circuit 140 from the sleep state to the wake-up state. When the control device 110 and the monitoring circuit 140 wake up, the process proceeds to step S203.

[0027] (Step S203) The control device 110 acquires the state of the second battery 120 monitored by the woken up monitoring circuit 140. When the state of the second battery 120 is acquired by the control device 110, the process proceeds to step S204.

[0028] (Step S204) The control device 110 judges whether or not power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420, etc., based on the state of the second battery 120. This judgment is made in order to prevent deterioration of the second battery 120. Therefore, the control device 110 can judge whether or not power can be supplied based on the power required by the load and the amount of power stored in the first battery 410, etc., taking into consideration the lower limit of the amount of power stored in the second battery 120, etc. If the control device 110 judges that power can be supplied (Yes in step S204), the process proceeds to step S207, and if the control device 110 judges that power cannot be supplied (No in step S204), the process proceeds to step S205.

[0029] (Step S205) The control device 110 responds with a refusal to the power supply request because it cannot supply power from the second battery 120 to the first battery 410 and the electronic system 420. For example, the control device 110 returns an ACK to the load or system that has transmitted the power supply request, indicating that power supply is not possible. When the control device 110 responds with a refusal to the power supply request, the process proceeds to step S206.

[0030] (Step S206) The control device 110 transitions from the wake-up state to a sleep state in which some functions (for example, functions other than the reception unit) are stopped. The control device 110 also transitions the monitoring circuit 140 in the wake-up state to a sleep state. When the control device 110 and the monitoring circuit 140 go to sleep, the process proceeds to step S201.

[0031] (Step S207) The control device 110 controls the latch circuit 150 to hold the DCDC converter (DDC) 130 in a charging / discharging state and to hold the relay 161 in a conducting state (latch-up operation). This starts power supply from the second battery 120 to the first battery 410 and the electronic system 420, and maintains the power supply state. When the DCDC converter (DDC) 130 and the relay 161 are held in their operating states, the process proceeds to step S208.

[0032] (Step S208) The control device 110 transitions from the wake-up state to a partial sleep state in which functions other than a specific function are stopped. This specific function is a clock function that will be performed in the following steps. The control device 110 also transitions the monitoring circuit 140 from the wake-up state to a sleep state. When the control device 110 goes into partial sleep and the monitoring circuit 140 goes into sleep, the process proceeds to step S209.

[0033] (Step S209) After the control device 110 has transitioned to a partial sleep state, the control device 110 starts measuring time. The time can be measured by using a predetermined counter. When the control device 110 starts measuring time, the process proceeds to step S210.

[0034] (Step S210) The control device 110 judges whether or not a predetermined time has elapsed since the start of timing. This judgment is made in order to prevent over-discharging of the second battery 120. Therefore, the predetermined time is appropriately set based on the capacity, the drain current, and the like of the second battery 120. If the control device 110 judges that the predetermined time has elapsed (Yes in step S210), the process proceeds to step S211.

[0035] (Step S211) The control device 110 transitions from the partial sleep state to a partial wake-up state in which the functions stopped during the partial sleep state are restarted. The control device 110 also transitions the monitoring circuit 140 from the sleep state to the wake-up state. When the control device 110 partially wakes up and the monitoring circuit 140 wakes up, the process proceeds to step S212.

[0036] (Step S212) The control device 110 acquires the state of the second battery 120 monitored by the woken up monitoring circuit 140. When the state of the second battery 120 is acquired by the control device 110, the process proceeds to step S213.

[0037] (Step S213) The control device 110 judges whether or not power can be supplied from the second battery 120 to the first battery 410, the electronic system 420, etc., based on the state of the second battery 120. This judgment is made to prevent deterioration and over-discharge of the second battery 120. If the control device 110 judges that power can be supplied (Yes in step S213), the process proceeds to step S208, and if the control device 110 judges that power cannot be supplied (No in step S213), the process proceeds to step S214.

[0038] By repeating the above-mentioned processes from step S208 to step S213, the state of the second battery 120 can be periodically checked at a predetermined time interval. Therefore, the control device 110 can grasp in advance the signs of deterioration or over-discharge of the second battery 120. In addition, in this loop process, the power supply request may be checked again together with the check of the state of the second battery 120. In this case, the control device 110 may wake up and control the latch circuit 150 again (such as changing the voltage command value of the DCDC converter 130) only if the power value specified by the power supply request has changed since the previous process.

[0039] (Step S214) The control device 110 transitions from the partial wake-up state to a wake-up state in which all functions are activated. When the control device 110 wakes up, the process proceeds to step S215.

[0040] (Step S215) The control device 110 controls the latch circuit 150 to hold the DCDC converter (DDC) 130 in a non-operating state where charging and discharging are not performed, and to hold the relay 161 in an operating state in a cutoff state (latch-up release). This ends the power supply from the second battery 120 to the first battery 410 and the electronic system 420. When the DCDC converter (DDC) 130 and the relay 161 are held in their operating states, the process proceeds to step S205.

[0041] According to the above-mentioned power supply control, when there is power available to the second battery 120, the latch circuit 150 latches up to keep the electric circuit (the DC-DC converter 130 and the relay 161) connecting the second battery 120 to the first battery 410 and the electronic system 420 electrically connected. As a result, as shown in FIG. 3, even if the control device 110 and the monitoring circuit 140 are put into sleep mode, the power supply from the second battery 120 to the first battery 410 and the electronic system 420 is continued. Therefore, the power of the second battery 120, the consumption of which is suppressed by the sleep mode of the control device 110 and the monitoring circuit 140, which consume more power than the electric circuit, can be effectively used for supplying power to a load.

[0042] <Second embodiment> [composition] Fig. 4 is a functional block diagram of a multi-battery system 200 including a control device 210 according to a second embodiment of the present disclosure and its peripheral parts. The functional block illustrated in Fig. 4 includes the multi-battery system 200, a first battery 410, an electronic system 420, and a plurality of loads 310, 320, and 330. This configuration can be mounted on, for example, a vehicle.

[0043] The first battery 410, the electronic system 420, and the multiple loads 310, 320, and 330 in the second embodiment are similar to those in the first embodiment, and are denoted by the same reference numerals and will not be described.

[0044] The multi-battery system 200 is a power supply system (secondary power supply system) for backing up and supplying power to the multiple loads 310, 320, and 330 in place of the first battery 410 when an abnormality occurs in the power supply from the first battery 410 to the multiple loads 310, 320, and 330 due to a power failure of the first battery 410 or the like. The multi-battery system 200 illustrated in FIG. 4 includes a control device 210 including a first control device 211 and a second control device 212, a second battery 120, a DC-DC converter 130, a monitoring circuit 140, a latch circuit 250 including a first latch circuit 251 and a second latch circuit 252, and multiple relays 161 to 165.

[0045] The second battery 120, the DCDC converter 130, the monitoring circuit 140, and the multiple relays 161 to 165 in the multi-battery system 200 of the second embodiment are similar to those in the multi-battery system 100 of the first embodiment described above, and the same reference symbols are used and some of the descriptions are omitted.

[0046] The first latch circuit 251 is configured to hold the operating state of the DCDC converter 130 based on an instruction from the first control device 211. More specifically, when a predetermined instruction is given from the first control device 211, the first latch circuit 251 latches up the DCDC converter 130 in an operating state in which charging and discharging are possible.

[0047] The second latch circuit 252 is configured to hold the operating state of the relay 161 based on an instruction from the second control device 212. More specifically, when a predetermined instruction is received from the second control device 212, the second latch circuit 252 latches up the relay 161 in a conductive state.

[0048] The latch-up control of the first latch circuit 251 and the second latch circuit 252 maintains at least an electrically connected state between the second battery 120 and the first battery 410 and the electronic system 420, and maintains a state in which power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420 (or the multiple loads 310, 320, and 330). Note that a well-known circuit configuration can be used for the first latch circuit 251 and the second latch circuit 252.

[0049] The first control device 211 is configured to control the first latch circuit 251 to effectively utilize the power of the second battery 120. The first control device 211 has a function (first control unit) of controlling the first latch circuit 251 based on an instruction from the second control device 212 to suitably control the operation state of the DCDC converter 130. The first control device 211 can suitably transition between a wake-up state in which all functions are activated and a sleep state in which only some functions (for example, a function that receives an instruction from the second control device 212) are activated and the remaining functions are stopped in order to reduce power consumption based on an instruction from the second control device 212. The detailed control of the first control device 211 will be described later.

[0050] The second control device 212 is configured to control the monitoring circuit 140 and the second latch circuit 252 in order to effectively utilize the power of the second battery 120. The second control device 212 has a function (acquisition unit) of acquiring the state of the second battery 120 via the monitoring circuit 140. The second control device 212 also has a function (acquisition unit) of accepting a predetermined power supply request from the outside of the multi-battery system 200. In the case of a vehicle, for example, this power supply request is transmitted at the start of a service from a load (for example, the electronic system 420) that consumes power from the first battery 410 while the vehicle is parked. The second control device 212 has a function (second control unit) of controlling the second latch circuit 252 based on the state of the second battery 120 when there is a power supply request, and appropriately controlling the operating state of the relay 161. Furthermore, the second control device 212 has a function (start-up control unit) capable of suitably transitioning between a wake-up state in which all functions are activated and a sleep state in which only some functions (for example, a function for receiving a power supply request) are activated and the remaining functions are stopped in order to reduce power consumption. This function can also instruct the first control device 211 to transition between a wake-up state in which all functions are activated and a sleep state in which some functions are stopped. This function can also instruct the monitoring circuit 140 to transition between a wake-up state in which all functions are activated and a sleep state in which all functions are stopped. Detailed control of the second control device 212 will be described later.

[0051] The function (reception unit) of the second control device 212 to receive a predetermined power supply request from outside the multi-battery system 200 may be included in the first control device 211. In this case, the first control device 211 that receives the power supply request will appropriately transition the wake-up state / sleep state of the second control device 212. The first control device 211 may also have a function (acquisition unit) of the second control device 212 to obtain the state of the second battery 120.

[0052] A part or all of the configuration of the first control device 211 may be typically configured as a microcomputer (main microcomputer) including a processor, a memory, an input / output interface, etc. A part or all of the configuration of the second control device 212 may be typically configured as a microcomputer (sub-microcomputer) including a processor, a memory, an input / output interface, etc. These microcomputers can respectively realize a part or all of the various functions described above by the processor reading and executing a program stored in the memory.

[0053] [control] Next, with further reference to Fig. 5A, Fig. 5B, Fig. 5C, and Fig. 6, the control performed by the control device 210 according to the second embodiment when the multi-battery system 200 is mounted on a vehicle will be described. Fig. 5A, Fig. 5B, and Fig. 5C are flowcharts for explaining the processing procedure of the power supply control performed by the control device 210. The processes in Fig. 5A, Fig. 5B, and Fig. 5C are connected by connectors X, Y, and Z. Fig. 6 is a timing chart of the power supply control performed by the control device 210 according to the second embodiment.

[0054] The power supply control shown in Figures 5A, 5B, and 5C is started when a predetermined state occurs in which there is no possibility of using the power of the second battery 120 provided redundantly as a backup power source, such as when the ignition of the vehicle is turned off (IG-OFF), and is repeatedly performed until the predetermined state is released. Note that, at the time when the power supply control is started, the first control device 211, the second control device 212, and the monitoring circuit 140 are all in a sleep state.

[0055] (Step S501) The second control device 212 determines whether or not a power supply request has been made in a sleep state in which some functions (e.g., functions other than the reception unit) are stopped. This power supply request is transmitted and received using an in-vehicle network such as a CAN. If the second control device 212 determines that a power supply request has been made (step S501, Yes), the process proceeds to step S502.

[0056] (Step S502) The second control device 212 transitions from a sleep state to a wake-up state in which all functions are activated. The second control device 212 also transitions the monitoring circuit 140 from the sleep state to the wake-up state. When the second control device 212 and the monitoring circuit 140 wake up, the process proceeds to step S503.

[0057] (Step S503) The second control device 212 acquires the state of the second battery 120 monitored by the woken up monitoring circuit 140. When the state of the second battery 120 is acquired by the second control device 212, the process proceeds to step S504.

[0058] (Step S504) The second control device 212 judges whether or not power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420, etc., based on the state of the second battery 120. This judgment is made to prevent deterioration of the second battery 120. Therefore, the second control device 212 can judge whether or not power can be supplied based on the power required by the load and the amount of power stored in the first battery 410, etc., taking into consideration the lower limit of the amount of power stored in the second battery 120, etc. If the second control device 212 judges that power can be supplied (step S504, Yes), the process proceeds to step S507, and if the second control device 212 judges that power cannot be supplied (step S504, No), the process proceeds to step S505.

[0059] (Step S505) The second control device 212 cannot supply power from the second battery 120 to the first battery 410 and the electronic system 420, and so responds with a refusal to the power supply request. For example, the second control device 212 returns an ACK to the load or system that has transmitted the power supply request, indicating that power supply is not possible. When the second control device 212 responds with a refusal to the power supply request, the process proceeds to step S506.

[0060] (Step S506) The second control device 212 transitions from the wake-up state to a sleep state in which some functions (for example, functions other than the reception unit) are stopped. The second control device 212 also transitions the monitoring circuit 140 in the wake-up state to a sleep state. When the second control device 212 and the monitoring circuit 140 go to sleep, the process proceeds to step S501.

[0061] (Step S507) The first control device 211 transitions from the sleep state to a wake-up state in which all functions are activated. This transition is performed based on an instruction from the second control device 212 that has determined in step S504 that power supply is possible. When the first control device 211 wakes up, the process proceeds to step S508.

[0062] (Step S508) The first control device 211 controls the first latch circuit 251 to hold the DCDC converter (DDC) 130 in a charging / discharging state (latch-up operation). The second control device 212 controls the second latch circuit 252 to hold the relay 161 in a conducting state (latch-up operation). This starts power supply from the second battery 120 to the first battery 410 and the electronic system 420, and maintains the power supply state. When the DCDC converter (DDC) 130 and the relay 161 are held in their operating states, the process proceeds to step S509.

[0063] (Step S509) The first control device 211 transitions from the wake-up state to a sleep state in which some functions are stopped. The second control device 212 transitions from the wake-up state to a partial sleep state in which functions other than a specific function are stopped. This specific function is a timing function to be performed in the following steps. Furthermore, the second control device 212 transitions the monitoring circuit 140 in the wake-up state to a sleep state. When the first control device 211 and the monitoring circuit 140 go to sleep and the second control device 212 goes to partial sleep, the process proceeds to step S510.

[0064] (Step S510) The second control device 212 starts measuring time after transitioning to a partial sleep state. The measurement of time can be performed by using a predetermined counter. When the second control device 212 starts measuring time, the process proceeds to step S511.

[0065] (Step S511) The second control device 212 judges whether a predetermined time has elapsed since the start of timing. This judgment is made in order to prevent over-discharging of the second battery 120. Therefore, the predetermined time is appropriately set based on the capacity, the drain current, and the like of the second battery 120. If the second control device 212 judges that the predetermined time has elapsed (Yes in step S511), the process proceeds to step S512.

[0066] (Step S512) The second control device 212 transitions the partial sleep state to a partial wake-up state in which the functions stopped during the partial sleep state are restarted. The second control device 212 also transitions the monitoring circuit 140 from the sleep state to the wake-up state. When the second control device 212 partially wakes up and the monitoring circuit 140 wakes up, the process proceeds to step S513.

[0067] (Step S513) The second control device 212 acquires the state of the second battery 120 monitored by the woken up monitoring circuit 140. When the state of the second battery 120 is acquired by the second control device 212, the process proceeds to step S514.

[0068] (Step S514) The second control device 212 judges whether or not power can be supplied from the second battery 120 to the first battery 410, the electronic system 420, etc., based on the state of the second battery 120. This judgment is made to prevent deterioration and over-discharge of the second battery 120. If the second control device 212 judges that power can be supplied (step S514, Yes), the process proceeds to step S509, and if the second control device 212 judges that power cannot be supplied (step S514, No), the process proceeds to step S515.

[0069] By repeating the above-mentioned processes from step S509 to step S514, the state of the second battery 120 can be periodically checked at a predetermined time interval. Therefore, the second control device 212 can grasp in advance the signs of deterioration of the second battery 120 or the signs of over-discharge. In this loop process, the power supply request may be checked again together with the state of the second battery 120. In this case, the first control device 211 may wake up and control the first latch circuit 251 again (such as changing the voltage command value of the DCDC converter 130) only if the power value specified by the power supply request has changed since the previous process.

[0070] (Step S515) The first control device 211 transitions from a sleep state to a wake-up state in which all functions are activated. The second control device 212 transitions from a partial wake-up state to a wake-up state in which all functions are activated. When the first control device 211 and the second control device 212 wake up, the process proceeds to step S516.

[0071] (Step S516) The first control device 211 controls the first latch circuit 251 to hold the DCDC converter (DDC) 130 in a non-operating state where charging and discharging are not performed (latch-up operation). The second control device 212 controls the second latch circuit 252 to hold the relay 161 in an interrupted state (latch-up release). This ends the power supply from the second battery 120 to the first battery 410 and the electronic system 420. When the DCDC converter (DDC) 130 and the relay 161 are held in their respective operating states, the process proceeds to step S517.

[0072] (Step S517) The first control device 211 transitions from the wake-up state to a sleep state in which some functions are stopped. When the first control device 211 goes to sleep, the process proceeds to step S505.

[0073] According to the above-mentioned power supply control, when there is power that can be supplied to the second battery 120, the electric circuit (the DC-DC converter 130 and the relay 161) that connects the second battery 120 to the first battery 410 and the electronic system 420 is kept in an electrically connected state by the latch-up operation in cooperation between the first latch circuit 251 and the second latch circuit 252. As a result, as illustrated in FIG. 6, even if the first control device 211, the second control device 212, and the monitoring circuit 140 are put into sleep mode, the power supply from the second battery 120 to the first battery 410 and the electronic system 420 is continued. Therefore, the power of the second battery 120, the consumption of which is suppressed by the sleep of the first control device 211, the second control device 212, and the monitoring circuit 140, which consume more power than the electric circuit, can be effectively used for power supply. Moreover, since the temporary startup for checking the state of the second battery 120 is only required for the second control device 212, power consumption can be further reduced compared to the first embodiment.

[0074] In addition, the multi-battery system 200 is configured to individually control the DCDC converter 130 and the relay 161 using the first control device 211 and the second control device 212. With this configuration, even if an abnormality occurs in the first control device 211 and the output voltage of the DCDC converter 130 becomes high and unintended charging of the second battery 120 is started, the normal second control device 212 can prevent charging of the second battery 120 by shutting off the relay 161. Also, even if an abnormality occurs in the second control device 212 and the relay 161 cannot be shut off, the normal first control device 211 can control the output voltage of the DCDC converter 130, so that overcharging of the second battery 120 can be prevented.

[0075] <Actions and Effects> As described above, according to the control device of each embodiment of the present disclosure, after starting up the control device in a predetermined situation, if the state of the battery of the secondary power supply system is such that it is capable of supplying power to a specified load, etc., the control device controls an electrical circuit between the battery and the specified load so as to maintain an electrical connection between the battery and the specified load, and stops some functions of the control device, etc.

[0076] This control makes it possible to suppress the power consumption of the control device while maintaining the power supply state from the battery to the specified load, etc. Therefore, the power that would have been consumed by some of the functions of the stopped control device can be added to the power supply to the specified load, etc., thereby realizing effective use of the power of the battery of the secondary power supply system.

[0077] The above describes one embodiment of the disclosed technology. However, the present disclosure can be understood as not only a control device, but also a control method executed by a control device having a processor and a memory, a control program for executing the control method, a computer-readable non-transitory storage medium storing the control program, and a vehicle equipped with a control device. [Industrial Applicability]

[0078] The control device and the like of the present disclosure can be used in a system that employs a redundant power supply configuration. [Explanation of symbols]

[0079] 100, 200 Multi-battery system 110, 210~212 Control device 120 Second Battery 130 DC-DC Converter 140 Monitoring circuit 150, 250~252 Latch circuit 161~165 Relay 310, 320, 330 Load 410 First Battery 420 Electronic Systems

Claims

1. A control device that controls power supply from a battery of a primary power supply system and a battery of a secondary power supply system to a predetermined load via an electric circuit, an acquisition unit for acquiring a state of a battery of the secondary power supply system; a start-up control unit that is capable of transitioning between start and stop states of the control device and controls the electric circuit based on the state of the battery of the secondary power supply system acquired by the acquisition unit; The control device, wherein the startup control unit controls the electrical circuit to maintain an electrical connection between the battery of the secondary power supply system and the specified load when the state of the battery of the secondary power supply system is capable of supplying power to the specified load after starting up the control device, and stops some of the functions of the control device.

2. 2. The control device according to claim 1, wherein, when a state of the battery of the secondary power supply system is not in a state capable of supplying power to the specified load after starting up the control device, the startup control unit controls the electric circuit to maintain a state in which the battery of the secondary power supply system and the specified load are electrically disconnected, and stops the control device.

3. The control device according to claim 1 , wherein the start-up control unit starts up the control device when a request for power supply is received from the predetermined load.

4. 2. The control device according to claim 1, wherein the activation control unit periodically activates the partial function of the control device while the partial function of the control device is stopped to determine a state of a battery of the secondary power supply system.

5. 2. The control device according to claim 1, wherein the electrical circuit includes a DC-DC converter that controls charging and discharging between a battery of the primary power supply system and a battery of the secondary power supply system, and a relay for disconnecting the battery of the secondary power supply system from the DC-DC converter.

6. 6. The control device according to claim 5, wherein the startup control unit maintains an electrically connected state between the battery of the secondary power supply system and the predetermined load by maintaining the DC-DC converter in a charge / discharge state and maintaining the relay in a conductive state.

7. The startup control unit includes a first control unit that controls the DC-DC converter and a second control unit that controls the relay, The control device according to claim 5, wherein one of the first control unit and the second control unit is equipped with the acquisition unit and the startup control unit, and the other control unit transitions the startup and shutdown states of the control device in accordance with control by the one control unit.

8. 8. The control device according to claim 7, wherein while the battery of the secondary power supply system and the specified load are maintained in an electrically connected state, the one control unit repeatedly starts and stops at predetermined time intervals to determine the state of the battery of the secondary power supply system.

9. The control device is mounted on a vehicle, 9. The control device according to claim 1, wherein the start-up control unit executes control of the electric circuit and start-up and stop state transitions based on a state of a battery of the secondary power supply system during a period from when an ignition of the vehicle is turned off to when it is turned on.

10. A control method executed by a control device that controls power supply from a battery of a primary power supply system and a battery of a secondary power supply system to a predetermined load via an electric circuit, comprising: obtaining a state of a battery of the secondary power supply system after starting up the control device; determining whether or not a state of the battery of the secondary power supply system is in a state in which power can be supplied to the predetermined load; controlling the electric circuit so that the battery of the secondary power supply system and the predetermined load are kept electrically connected when the battery of the secondary power supply system is in a state in which power can be supplied to the predetermined load; and controlling the electrical circuit so as to maintain a state in which the battery of the secondary power supply system and the specified load are electrically connected, and then stopping a function of a part of the control device.

11. A control program to be executed by a computer of a control device that controls power supply from a battery of a primary power supply system and a battery of a secondary power supply system to a predetermined load via an electric circuit, comprising: obtaining a state of a battery of the secondary power supply system after starting up the control device; determining whether or not a state of the battery of the secondary power supply system is in a state in which power can be supplied to the predetermined load; controlling the electric circuit so that the battery of the secondary power supply system and the predetermined load are kept electrically connected when the battery of the secondary power supply system is in a state in which power can be supplied to the predetermined load; and a step of controlling the electrical circuit so as to maintain a state in which the battery of the secondary power supply system and the specified load are electrically connected, and then stopping a function of a part of the control device.

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