Control device, control method, and recording medium

Abstract

This invention provides a control device, a control method, and a recording medium. The control device controls the power supply from a storage battery to a predetermined load via a circuit, and includes: an acquisition unit that acquires the state of the storage battery; a start control unit capable of executing start and stop state transitions of the control device, and controlling the circuit based on the state of the storage battery acquired by the acquisition unit; the start control unit, after starting the control device, if the state of the storage battery is such that it can supply power to the predetermined load, controls the circuit in a manner that maintains the electrical connection between the storage battery and the predetermined load, and stops a portion of the functions of the control device.

Description

Technical Field

[0001] This disclosure relates to a control device for controlling the power supply from a storage battery to a predetermined load, etc. Background Technology

[0002] Japanese Patent Application Publication No. 2021-123145 discloses a structure in which the power supply structure is set up independently in the primary power supply system and the secondary power supply system in order to improve the reliability of the power supply of the vehicle platform in vehicles performing autonomous driving. Summary of the Invention

[0003] Vehicles equipped with an autonomous driving system as described in Japanese Patent Application Publication No. 2021-123145, when not using the autonomous driving function and when the vehicle is parked, only have electricity (energy) stored in the battery of the secondary power system. There is a problem that this electricity cannot be effectively utilized. To address this problem, methods such as supplying the power from the secondary power system battery to the load of the primary power system when the vehicle is parked can be considered. Further research is warranted to minimize supply-related losses and to utilize the electricity effectively.

[0004] This disclosure was made in view of the aforementioned issues. The object of this disclosure is to provide a control device, etc., that can effectively utilize the power of a battery in a secondary power supply system.

[0005] To address the aforementioned issues, one aspect of this disclosure is a control device that controls the power supply from a battery to a predetermined load via a circuit, and includes an acquisition unit for obtaining the battery's state and a start-up control unit. The start-up control unit is capable of executing start-up and stop state transitions of the control device. The start-up control unit controls the circuit based on the battery state obtained by the acquisition unit. After starting the control device, if the battery state is such that it can supply power to the predetermined load, the start-up control unit controls the circuit in a manner that maintains the electrical connection between the battery and the predetermined load, and disables a portion of the control device's functions.

[0006] When the control device of this disclosure supplies power from the battery of the secondary power supply system to the load of the primary power supply system, it maintains the circuit between the battery and the load in a state that electrically connects the battery and the load, while simultaneously stopping some functions of the control device. Therefore, the power of the battery can be utilized effectively. Attached Figure Description

[0007] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which the same symbols denote the same elements, wherein:

[0008] Figure 1 A functional block diagram of a multi-battery system and its peripheral portion that includes the control device according to the first embodiment of this disclosure;

[0009] Figure 2A A flowchart illustrating the power supply control process performed by the control device according to the first embodiment;

[0010] Figure 2B A flowchart illustrating the power supply control process performed by the control device according to the first embodiment;

[0011] Figure 3 A timing diagram of the operation of each structure in the power supply control of the control device according to the first embodiment;

[0012] Figure 4 A functional block diagram of a multi-battery system and its peripheral portion that includes the control device according to the second embodiment of this disclosure;

[0013] Figure 5A A flowchart illustrating the power supply control process performed by the control device according to the second embodiment;

[0014] Figure 5B A flowchart illustrating the power supply control process performed by the control device according to the second embodiment;

[0015] Figure 5C A flowchart illustrating the power supply control process performed by the control device according to the second embodiment;

[0016] Figure 6 This is a timing diagram of the operation of each structure in the power supply control of the control device according to the second embodiment. Detailed Implementation

[0017] The control device disclosed herein latches up the circuit between the load and the battery to maintain the electrical connection between the load and the battery. When there is available power in the battery, the latch operates, placing the control device into a low-power-consumption sleep state while maintaining power supply from the battery to the load. This suppresses the reduction of available power from the battery to the load, thereby enabling efficient power utilization.

[0018] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0019] First Implementation Method

[0020] structure

[0021] Figure 1This is a functional block diagram of a multi-battery system 100 and its peripheral components, including the control device 110 involved in the first embodiment of this disclosure. Figure 1 The functional blocks illustrated herein structurally include a multi-battery system 100, a first battery 410, an electronic system 420, and multiple loads 310, 320, and 330. These structures can be mounted, for example, on a vehicle.

[0022] The first battery 410 is a power supply source (primary power system) that supplies power to the electronic system 420 and multiple loads 310, 320, and 330. This first battery 410 is, for example, a secondary battery such as a lithium-ion battery capable of charging and discharging. In the case of a vehicle, the first battery 410 could be an auxiliary battery used to supply power to onboard equipment unrelated to the vehicle's drive.

[0023] Electronic system 420 is a predetermined device (load) that receives power from the first battery 410 and drives it. Regarding electronic system 420, if it is a vehicle, examples of in-vehicle equipment (air conditioning, lighting equipment, etc.) unrelated to the vehicle's drive can be given. The number of electronic systems 420 is not limited. Figure 1 The quantity shown.

[0024] Multiple loads 310, 320, and 330 are predetermined devices that receive power from a first battery 410, which serves as a primary power supply system, and from a multi-battery system 100, which serves as a secondary power supply system. The number of multiple loads 310, 320, and 330 is not limited. Figure 1 The quantities shown. As these multiple loads 310, 320 and 330, it is possible to exemplify loads that require the use of the redundant power structure of the multi-battery system 100 (e.g., autonomous driving systems, etc., if it is a vehicle).

[0025] The multi-battery system 100 is a power supply system (secondary power supply system) used to replace the first battery 410 and provide backup power to the multiple loads 310, 320 and 330 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 other reasons. Figure 1 The multi-battery system 100 illustrated includes a control device 110, a second battery 120, a DC-DC converter 130, a monitoring circuit 140, a latching circuit 150, and multiple relays 161 to 165.

[0026] The second battery 120 is configured as a rechargeable lithium-ion battery or capacitor. This second battery 120 is connected to the DC-DC converter 130 and the relay 161 in a manner that allows it to charge the first battery 410 and discharge its stored power to the first battery 410 and the electronic system 420. Furthermore, the second battery 120 is connected to multiple loads 310, 320, and 330 via relays 161, 163, and 165 in a manner that allows it to supply its stored power. The second battery 120 is a power source that supplies power to operate (start) the control device 110, the DC-DC converter 130, the monitoring circuit 140, the latching circuit 150, and the multiple relays 161 to 165.

[0027] The DC-DC converter 130 is configured to, based on instructions from the control device 110 or other electronic control unit (ECU) not shown, input power from the first battery 410 and convert it into power of a predetermined voltage for output to the second battery 120, or input power from the second battery 120 and convert it into power of a predetermined voltage for output to the first battery 410 or the electronic system 420. This DC-DC converter 130 forms part of a circuit that connects the first battery 410 and the electronic system 420 (primary power system) and the second battery 120 (secondary power system).

[0028] The monitoring circuit 140 is a structure for monitoring the state of the second battery 120. The state of the second battery 120 can be exemplified by physical quantities such as voltage, current, and temperature. The monitoring circuit 140 may also be composed, for example, of only detection elements such as sensors that measure physical quantities. The monitoring circuit 140 may also be configured to include an integrated circuit (IC) that further includes a processor and a memory for calculating the values ​​detected by the detection elements.

[0029] Relay 161 is a switching element capable of switching between on and off states of electrical circuitry. Relay 161 is provided for switching the electrical connection between the DC-DC converter 130 and the second battery 120. Figure 1 In the example, relay 161 is inserted between DC-DC converter 130 and second battery 120. Alternatively, relay 161 can also be inserted between second battery 120 and ground (GND). For this relay 161, an excitation-type mechanical relay or a semiconductor relay using a field-effect transistor (e.g., MOSFET) can be used. Relay 161 forms part of the circuit that connects first battery 410 and electronic system 420 (primary power system) and second battery 120 (secondary power system).

[0030] The latching circuit 150 is a structure used to maintain the operating state of the DC-DC converter 130 and the operating state of the relay 161 based on an instruction from the control device 110. More specifically, when a predetermined instruction is issued from the control device 110 in response to the acceptance of a power supply instruction, the latching circuit 150 latches the DC-DC converter 130 in a charge-dischargeable operating state and latches the relay 161 in a conducting state, maintaining at least the second battery 120, the first battery 410, and the electronic system 420 electrically connected. Through this latching control, a state in which power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420 (or multiple loads 310, 320, and 330) is maintained. In addition, a known circuit structure can be used in this latching circuit 150.

[0031] Multiple relays 162 to 165 are switching elements capable of switching the on / off state of electricity based on instructions from control device 110 or other electronic control devices (ECUs) not shown. Relay 162 is inserted between the first battery 410 and multiple loads 310, 320, and 330. Relay 163 is inserted between relay 161 and relay 162. Relay 164 is inserted between relay 162 and load 320. Relay 165 is inserted between relay 162 and load 330. The number of multiple relays 164 and 165 connecting loads 320 and 330 to the multi-battery system 100 is not limited to [specific number missing]. Figure 1 The number shown. The number of multiple relays 164 and 165 that connect loads 320 and 330 to the multi-battery system 100 increases or decreases depending on the number of loads connected to the multi-battery system 100.

[0032] The control device 110 is configured to control the monitoring circuit 140 and the latching circuit 150 to effectively utilize the power of the second battery 120. The control device 110 has the function of obtaining the state of the second battery 120 via the monitoring circuit 140 (obtaining unit). Furthermore, the control device 110 has the function of accepting predetermined power supply requests from outside the multi-battery system 100 (accepting unit). This power supply request, for example in the case of a vehicle, is sent from a load (e.g., electronic system 420) that consumes power from the first battery 410 when the vehicle is parked, at the start of service. Then, the control device 110 has the function of, upon receiving a power supply request, instructing the latching circuit 150 based on the state of the second battery 120, and appropriately controlling the DC-DC converter 130 and the relay 161 (starting control unit). Furthermore, the control device 110 has a function (start control unit) capable of appropriately switching between an awake state where all functions are operational and a sleep state where only a portion of functions (e.g., the function that accepts power supply requests) are operational to suppress power consumption, while the remaining functions are stopped. This function (start control unit) can also instruct the monitoring circuit 140 to switch between the awake state where all functions are operational and the sleep state where all functions are stopped. Detailed control of the control device 110 will be described below.

[0033] Furthermore, part or all of the structure of the control device 110 can be configured as a microcomputer, typically including a processor, memory, and input / output interfaces. This microcomputer can read and execute programs stored in memory via the processor to achieve some or all of the aforementioned various functions.

[0034] control

[0035] Next, further reference Figure 2A , Figure 2B as well as Figure 3 The control performed by the control device 110 in the first embodiment when the multi-battery system 100 is mounted on a vehicle will be described. Figure 2A as well as Figure 2B A flowchart illustrating the processing sequence of power supply control performed by control device 110. Figure 2A processing and Figure 2B The processing is achieved by connecting the symbols V and W. Figure 3 This is a timing diagram of the power supply control performed by the control device 110 according to the first embodiment.

[0036] Figure 2A as well as Figure 2BThe power supply control shown begins when, for example, the vehicle's ignition switch is turned off (IG-OFF), and the possibility of using the power of the second battery 120, which is redundantly provided as a backup power source, is zero. Figure 2A as well as Figure 2B The power supply control shown is repeatedly implemented until the predetermined state is lifted. In addition, it is set that at the time when the power supply control is started, both the control device 110 and the monitoring circuit 140 are in a sleep state.

[0037] Step S201

[0038] While in a sleep state where some functions (e.g., functions other than the receiving unit) are disabled, the control device 110 determines whether there is a power supply request. This power supply request may be transmitted or received using a vehicle network such as CAN. If the control device 110 determines that there is a power supply request (step S201, yes), the process proceeds to step S202.

[0039] Step S202

[0040] The control device 110 transitions from a sleep state to a wake-up state, enabling all functions to operate. Furthermore, the control device 110 wakes up the monitoring circuit 140, which was in a sleep state. When the control device 110 and the monitoring circuit 140 are awakened, the process proceeds to step S203.

[0041] Step S203

[0042] The control device 110 obtains the status of the second battery 120 as monitored by the wake-up monitoring circuit 140. When the control device 110 obtains the status of the second battery 120, the process proceeds to step S204.

[0043] Step S204

[0044] The control device 110 determines whether power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420, based on the state of the second battery 120. This determination is made to prevent deterioration of the second battery 120. Therefore, the control device 110 can determine whether power supply can be performed based on factors such as the lower limit of the second battery 120's capacity and the power requested by the load, the capacity of the first battery 410, etc. If the control device 110 determines that power supply can be performed (step S204, Yes), the process proceeds to step S207. If the control device 110 determines that power supply cannot be performed (step S204, No), the process proceeds to step S205.

[0045] Step S205

[0046] Since power cannot be supplied from the second battery 120 to the first battery 410 and the electronic system 420, the control device 110 responds to the power supply request by rejecting it. For example, the control device 110 replies with an ACK indicating that power supply cannot be provided to the load or system that sent the power supply request. When the control device 110 rejects the power supply request, the process proceeds to step S206.

[0047] Step S206

[0048] The control device 110 transitions from an active state to a sleep state, which disables some functions (e.g., functions other than the receiving unit). Furthermore, the control device 110 transitions the active monitoring circuit 140 to a sleep state. When both the control device 110 and the monitoring circuit 140 are in sleep mode, the process proceeds to step S201.

[0049] Step S207

[0050] The control device 110 controls the latching circuit 150 to keep the DC-DC converter (DDC) 130 in a charging / discharging state and to keep the relay 161 in a conducting state (lock-up operation). This initiates and maintains power supply from the second battery 120 to the first battery 410 and the electronic system 420. While the DC-DC converter (DDC) 130 and the relay 161 remain in their respective operating states, the process proceeds to step S208.

[0051] Step S208

[0052] The control device 110 transitions from a wake-up state to a partially sleep state, where a specific function is stopped except for a timing function implemented in subsequent steps. Additionally, the control device 110 transitions the monitoring circuit 140 from a wake-up state to a sleep state. When both the control device 110 and the monitoring circuit 140 are in sleep mode, the process proceeds to step S209.

[0053] Step S209

[0054] After the control device 110 enters a partial sleep state, it begins measuring the time. The time measurement can be performed using a predetermined counter. If timing is started by the control device 110, the process proceeds to step S210.

[0055] Step S210

[0056] The control device 110 determines whether a predetermined time has elapsed since the start of timing. This determination is made to prevent over-discharge of the second battery 120. Therefore, the predetermined time is appropriately set based on the capacity of the second battery 120, the outflow current, etc. If the control device 110 determines that the predetermined time has elapsed (step S210, Yes), the process proceeds to step S211.

[0057] Step S211

[0058] The control device 110 transitions from a partially dormant state to a partially awakened state, resuming functions that had stopped due to the partial dormancy. Furthermore, the control device 110 awakens the monitoring circuit 140, which was in a dormant state. When the control device 110 is partially awakened and the monitoring circuit 140 is also awakened, the process proceeds to step S212.

[0059] Step S212

[0060] The control device 110 obtains the status of the second battery 120 as monitored by the wake-up monitoring circuit 140. When the control device 110 obtains the status of the second battery 120, the process proceeds to step S213.

[0061] Step S213

[0062] Based on the state of the second battery 120, the control device 110 determines whether power can be supplied from the second battery 120 to the first battery 410 and the electronic system 420, etc. This determination is made to prevent the second battery 120 from deteriorating or over-discharging. If the control device 110 determines that power supply can be provided (step S213, Yes), the process proceeds to step S208. If the control device 110 determines that power supply cannot be provided (step S213, No), the process proceeds to step S214.

[0063] By repeating steps S208 to S213, the state of the second battery 120 can be periodically checked at predetermined time intervals. Therefore, the control device 110 can anticipate signs of deterioration and over-discharge in the second battery 120. Furthermore, in this cyclic process, the power supply request can be re-checked along with the check of the second battery 120's state. In this case, it can be configured such that the control device 110 is activated only if the power value indicated by the power supply request changes since the last processing, and the latch circuit 150 (changes in the voltage indication value of the DC-DC converter 130, etc.) is controlled again.

[0064] Step S214

[0065] The control device 110 transitions from a partially awakened state to a fully awakened state where all functions are operational. When the control device 110 is awakened, the process proceeds to step S215.

[0066] Step S215

[0067] The control device 110 controls the latching circuit 150 to keep the DC-DC converter (DDC) 130 in a non-operating state where it is not charging or discharging, and to keep the relay 161 in the off state (lockout released). This terminates the power supply from the second battery 120 to the first battery 410 and the electronic system 420, etc. When the DC-DC converter (DDC) 130 and the relay 161 remain in their respective operating states, the process proceeds to step S205.

[0068] According to the aforementioned power supply control, when there is sufficient power to be supplied in the second battery 120, the latching circuit 150 maintains the electrical connection of the circuit (DC-DC converter 130 and relay 161) connecting the second battery 120, the first battery 410, and the electronic system 420 through its latching operation. Thus, as... Figure 3 As illustrated, even when the control device 110 and monitoring circuit 140 are in sleep mode, the power supply from the second battery 120 to the first battery 410 and electronic system 420 continues. Therefore, the power consumed by the second battery 120, which is suppressed by the sleep mode of the control device 110 and monitoring circuit 140 (which consume more power than the circuit), can be effectively utilized to supply power to loads, etc.

[0069] Second Implementation Method

[0070] structure

[0071] Figure 4 This is a functional block diagram of a multi-battery system 200 and its peripheral components, including the control device 210 involved in the second embodiment of this disclosure. Figure 4 The illustrated functional blocks structurally include a multi-battery system 200, a first battery 410, an electronic system 420, and multiple loads 310, 320, and 330. These structures can be mounted on, for example, a vehicle.

[0072] The first battery 410, electronic system 420, and multiple loads 310, 320, and 330 in this second embodiment are the same as those in the first embodiment described above. The first battery 410, electronic system 420, and multiple loads 310, 320, and 330 in this second embodiment are labeled with the same reference numerals. Furthermore, descriptions are omitted.

[0073] The multi-battery system 200 is a power supply system (secondary power supply system) used to replace the first battery 410 and provide backup power to the multiple loads 310, 320 and 330 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 other reasons. Figure 4 The multi-battery system 200 illustrated includes a control device 210 consisting of 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 latching circuit 250 including a first latching circuit 251 and a second latching circuit 252, and a plurality of relays 161 to 165.

[0074] The second battery 120, DC-DC converter 130, monitoring circuit 140, and multiple relays 161 to 165 in the multi-battery system 200 of this second embodiment are the same as those in the multi-battery system 100 of the first embodiment described above. The second battery 120, DC-DC converter 130, monitoring circuit 140, and multiple relays 161 to 165 are marked with the same reference numerals. Descriptions of parts related to the second battery 120, DC-DC converter 130, monitoring circuit 140, and multiple relays 161 to 165 are omitted.

[0075] The first latch circuit 251 is a structure for maintaining the operating state of the DC-DC converter 130 based on an instruction from the first control device 211. More specifically, when a predetermined instruction is issued from the first control device 211, the first latch circuit 251 latches the DC-DC converter 130 into a charging and discharging operating state.

[0076] The second latching circuit 252 is a structure for maintaining the operating state of the relay 161 based on an instruction from the second control device 212. More specifically, when a predetermined instruction is issued from the second control device 212, the second latching circuit 252 latches the relay 161 into an on state.

[0077] By controlling the latching of the first latching circuit 251 and the second latching circuit 252, the second battery 120, the first battery 410, and the electronic system 420 can be kept electrically connected. Furthermore, the ability to supply power from the second battery 120 to the first battery 410 and the electronic system 420 (or multiple loads 310, 320, and 330) can be maintained. Moreover, known circuit structures can be used in the first latching circuit 251 and the second latching circuit 252.

[0078] The first control device 211 is a structure used to control the first latch circuit 251 in order to effectively utilize the power of the second battery 120. This first control device 211 has the function of controlling the first latch circuit 251 based on instructions from the second control device 212, and appropriately controlling the operating state of the DC-DC converter 130 (first control unit). Furthermore, the first control device 211 can appropriately switch between a wake-up state (where all functions are activated) and a sleep state (where only some functions are activated to suppress power consumption, e.g., functions that receive instructions from the second control device 212) and the remaining functions are stopped, based on instructions from the second control device 212. Detailed control of this first control device 211 will be described below.

[0079] The second control device 212 is a structure used to control the monitoring circuit 140 and the second latching circuit 252 in order to effectively utilize the power of the second battery 120. This second control device 212 has the function of obtaining the state of the second battery 120 via the monitoring circuit 140 (obtaining unit). Furthermore, the second control device 212 has the function of accepting predetermined power supply requests from outside the multi-battery system 200 (accepting unit). Such power supply requests are sent, for example, in the case of a vehicle, when parked, from loads that consume power from the first battery 410 (e.g., electronic system 420), etc., at the start of service. Moreover, the second control device 212 has the function of controlling the second latching circuit 252 based on the state of the second battery 120 when a power supply request is received, and appropriately controlling the operating state of the relay 161 (second control unit). Furthermore, the second control device 212 has a function (start-up control unit) capable of appropriately switching between an awake state where all functions are operational and a sleep state where only a portion of functions (e.g., the function that accepts power supply requests) are operational to suppress power consumption, while the remaining functions are stopped. This function can also instruct the first control device 211 to switch between an awake state where all functions are operational and a sleep state where some functions are stopped. Additionally, this function can also instruct the monitoring circuit 140 to switch between an awake state where all functions are operational and a sleep state where all functions are stopped. Detailed control of this second control device 212 will be described below.

[0080] Furthermore, the function (acceptance unit) of the second control device 212 to accept predetermined power supply requests from outside the multi-battery system 200 can also be possessed by the first control device 211. In this case, the first control device 211, having accepted the power supply request, appropriately changes the wake-up state / sleep state of the second control device 212. Additionally, the function (acquisition unit) of the second control device 212 to obtain the status of the second battery 120 can also be possessed by the first control device 211.

[0081] The structure of the first control device 211 described above may be part or all of a microcomputer (host) typically including a processor, memory, and input / output interfaces. Similarly, the structure of the second control device 212 may be part or all of a microcomputer (subcomputer) typically including a processor, memory, and input / output interfaces. These microcomputers can read and execute programs stored in memory to perform part or all of the various functions described above.

[0082] control

[0083] Next, further reference Figure 5A , Figure 5B , Figure 5C ,as well as Figure 6 The control performed by the control device 210 in the second embodiment, in the case where the multi-battery system 200 is mounted on a vehicle, will be described. Figure 5A , Figure 5B ,as well as Figure 5C A flowchart illustrating the processing sequence of power supply control performed by control device 210. Figure 5A , Figure 5B ,as well as Figure 5C The various processes are connected by the connecting symbols X, Y, and Z. Figure 6 This is a timing diagram of the power supply control performed by the control device 210 according to the second embodiment.

[0084] Figure 5A , Figure 5B ,as well as Figure 5C The power supply control shown begins when, for example, the vehicle's ignition switch is turned off (IG-OFF), and the possibility of using the power of the second battery 120, which is redundantly provided as a backup power source, is zero. Figure 5A , Figure 5B ,as well as Figure 5C The power supply control shown is repeatedly implemented until the predetermined state is lifted. In addition, it is assumed 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 dormant state.

[0085] Step S501

[0086] The second control device 212 determines whether there is a power supply request while in a sleep state where some functions (e.g., functions other than the receiving unit) are stopped. This power supply request is transmitted and received using an in-vehicle network such as CAN. If the second control device 212 determines that there is a power supply request (step S501, Yes), the process proceeds to step S502.

[0087] Step S502

[0088] The second control device 212 transitions from a sleep state to a wake-up state, enabling all functions to operate. Furthermore, the second control device 212 wakes up the monitoring circuit 140, which was in a sleep state. When the second control device 212 and the monitoring circuit 140 are awakened, the process proceeds to step S503.

[0089] Step S503

[0090] The second control device 212 acquires the status of the second battery 120 as monitored by the awakened monitoring circuit 140. When the status of the second battery 120 is acquired by the second control device 212, the process proceeds to step S504.

[0091] Step S504

[0092] The second control device 212 determines whether power supply from the second battery 120 to the first battery 410 and electronic system 420 is possible based on the state of the second battery 120. This determination is made to prevent deterioration of the second battery 120. Therefore, the second control device 212 can determine whether power supply is possible based on factors such as the lower limit of the second battery 120's capacity and the power requested by the load, the capacity of the first battery 410, etc. If the second control device 212 determines that power supply is possible (step S504, Yes), the process proceeds to step S507. If the second control device 212 determines that power supply is not possible (step S504, No), the process proceeds to step S505.

[0093] Step S505

[0094] Since power cannot be supplied from the second battery 120 to the first battery 410 and the electronic system 420, the second control device 212 responds to the power supply request by rejecting it. For example, the second control device 212 replies with an ACK indicating that power supply cannot be provided to the load or system that sent the power supply request. When the second control device 212 rejects the power supply request, the process proceeds to step S506.

[0095] Step S506

[0096] The second control device 212 transitions from an active state to a sleep state, which disables some functions (e.g., functions other than the receiving unit). Furthermore, the second control device 212 transitions the active monitoring circuit 140 to a sleep state. When both the second control device 212 and the monitoring circuit 140 are in sleep mode, the process proceeds to step S501.

[0097] Step S507

[0098] The first control device 211 transitions from a dormant state to a wake-up state, enabling all functions to operate. This transition is based on an instruction from the second control device 212, which was determined in step S504 above to be capable of providing power. When the first control device 211 wakes up, the process proceeds to step S508.

[0099] Step S508

[0100] The first control device 211 controls the first latch circuit 251 to keep the DC-DC converter (DDC) 130 in a charging / discharging state (lock-up operation). Furthermore, the second control device 212 controls the second latch circuit 252 to keep the relay 161 in a conducting state (lock-up operation). This initiates power supply from the second battery 120 to the first battery 410 and the electronic system 420, etc. This power supply is then maintained. While the DC-DC converter (DDC) 130 and the relay 161 remain in their respective operating states, the process proceeds to step S509.

[0101] Step S509

[0102] The first control device 211 transitions from a wake-up state to a sleep state that disables some functions. Furthermore, the second control device 212 transitions from a wake-up state to a partial sleep state that disables functions other than a specific one. This specific function refers to the timing function implemented in subsequent steps. Additionally, the second control device 212 transitions the wake-up monitoring circuit 140 to a sleep state. When the first control device 211 and monitoring circuit 140 are in sleep mode, and the second control device 212 is partially in sleep mode, the process proceeds to step S510.

[0103] Step S510

[0104] After the second control device 212 transitions to a partial sleep state, it begins measuring the time. The time measurement can be performed using a predetermined counter. If timing is started via the second control device 212, the process proceeds to step S511.

[0105] Step S511

[0106] The second control device 212 determines whether a predetermined time has elapsed since the start of timing. This determination is made to prevent over-discharge of the second battery 120. Therefore, the predetermined time is appropriately set based on the capacity of the second battery 120, the outflow current, etc. If the second control device 212 determines that the predetermined time has elapsed (step S511, yes), the process proceeds to step S512.

[0107] Step S512

[0108] The second control device 212 transitions from a partially dormant state to a partially awakened state that restarts functions that were stopped due to the partial dormancy. Furthermore, the second control device 212 awakens the monitoring circuit 140, which was in a dormant state. When the second control device 212 is partially awakened and the monitoring circuit 140 is also awakened, the process proceeds to step S513.

[0109] Step S513

[0110] The second control device 212 acquires the status of the second battery 120 as monitored by the awakened monitoring circuit 140. When the status of the second battery 120 is acquired by the second control device 212, the process proceeds to step S514.

[0111] Step S514

[0112] The second control device 212 determines whether power supply from the second battery 120 to the first battery 410 and the electronic system 420 is possible based on the state of the second battery 120. This determination is made to prevent deterioration and over-discharge of the second battery 120. If the second control device 212 determines that power supply is possible (step S514, Yes), the process proceeds to step S509. If the second control device 212 determines that power supply is not possible (step S514, No), the process proceeds to step S515.

[0113] By repeating steps S509 to S514, the state of the second battery 120 can be periodically checked at predetermined time intervals. Therefore, the second control device 212 can anticipate signs of deterioration and over-discharge in the second battery 120. Furthermore, in this cyclic process, the power supply request can be re-checked along with the check of the second battery 120's state. In this case, it can be configured such that the first control device 211 is activated only if the power value indicated by the power supply request changes since the last processing, and the first latch circuit 251 (changes in the voltage indication value of the DC-DC converter 130, etc.) is controlled again.

[0114] Step S515

[0115] The first control device 211 transitions from a dormant state to a wake-up state that enables all functions. Furthermore, the second control device 212 transitions from a partially awakened state to a wake-up state that enables all functions. When both the first control device 211 and the second control device 212 are awakened, the process proceeds to step S516.

[0116] Step S516

[0117] The first control device 211 controls the first latch circuit 251 to keep the DC-DC converter (DDC) 130 in a non-operational state (locked-up operation) where it does not charge or discharge. Furthermore, the second control device 212 controls the second latch circuit 252 to keep the relay 161 in an off state (locked-up release). This terminates the power supply from the second battery 120 to the first battery 410 and the electronic system 420, etc. When the DC-DC converter (DDC) 130 and the relay 161 remain in their respective operating states, the process proceeds to step S517.

[0118] Step S517

[0119] The first control device 211 transitions from a wake-up state to a sleep state that disables some functions. When the first control device 211 is in sleep mode, the process proceeds to step S505.

[0120] According to the aforementioned power supply control, when there is sufficient power to be supplied in the second battery 120, the circuits (DC-CDC converter 130 and relay 161) connecting the second battery 120, the first battery 410, and the electronic system 420, etc., are kept electrically connected through the coordinated latching operation of the first latching circuit 251 and the second latching circuit 252. Thus, as... Figure 6As illustrated, even when the first control device 211, the second control device 212, and the monitoring circuit 140 are in sleep mode, power supply from the second battery 120 to the first battery 410 and the electronic system 420 continues. Therefore, the power consumed by the second battery 120, which is suppressed by the sleep mode of the first control device 211, the second control device 212, and the monitoring circuit 140 (which consume more power than the circuit), can be effectively utilized for power supply. Furthermore, since the temporary start-up for checking the state of the second battery 120 is performed solely by the second control device 212, power consumption can be further suppressed compared to the first embodiment.

[0121] Furthermore, the multi-battery system 200 employs a structure that uses a first control device 211 and a second control device 212 to independently control the DC-DC converter 130 and the relay 161. With this structure, for example, even if an malfunction occurs in the first control device 211, causing the output voltage of the DC-DC converter 130 to rise and unintentionally initiating charging of the second battery 120, the relay 161 can be deactivated using the normal second control device 212, thereby preventing charging of the second battery 120. Furthermore, for example, even if an malfunction occurs in the second control device 212 and the relay 161 fails to deactivate, the output voltage of the DC-DC converter 130 can still be controlled by the normal first control device 211, thus preventing overcharging of the second battery 120.

[0122] Function / Effect

[0123] As described above, in a predetermined state, after the control device is started, and the battery of the secondary power system is in a state where it can supply power to a predetermined load, the control device controls the circuit between the battery and the predetermined load in such a way that the battery and the predetermined load are electrically connected, and stops some functions of the control device.

[0124] This control allows for the maintenance of power supply from the battery to predetermined loads, while simultaneously suppressing power consumption by the control device. Therefore, power that would otherwise be consumed by a portion of the control device's functions can be added to the power supply to predetermined loads. Consequently, efficient utilization of the battery power in the secondary power system can be achieved.

[0125] The above describes one embodiment of the technology disclosed herein. This disclosure can be viewed not only as a control device, but also as a control method executed by a control device equipped with a processor and 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 the control device, etc.

[0126] The control device and the like disclosed herein can utilize systems employing redundant power supply structures.

Claims

1. A control device for controlling the supply of power from a storage battery to a predetermined load via a circuit, comprising: The acquisition unit acquires the state of the battery; as well as The start-up control unit is capable of executing the start-up and stop state transitions of the control device, controlling the circuit based on the state of the battery obtained by the acquisition unit, and, after starting the control device, controlling the circuit while maintaining the electrical connection between the battery and the predetermined load if the battery is in a state capable of supplying power to the predetermined load, and disabling a portion of the functions of the control device. The circuit includes a DC-DC converter and a relay. The DC-DC converter controls the charging and discharging of the battery. The relay is used to disconnect the battery from the DC-DC converter. The starting control unit includes a first control unit for controlling the DC-DC converter and a second control unit for controlling the relay. The control unit of one of the first control unit and the second control unit includes the acquisition unit and the start control unit, and the control unit of the other control unit changes the start and stop states of the control device according to the control implemented by the control unit of the first control unit.

2. The control device as claimed in claim 1, wherein, When the starting control unit starts the control device and the battery is not in a state where it can supply power to the predetermined load, it controls the circuit in a way that keeps the battery and the predetermined load electrically disconnected, and stops the control device.

3. The control device as described in claim 1, wherein, The start-up control unit starts the control device when it receives a power supply request from the predetermined load.

4. The control device as claimed in claim 1, wherein, During the period when the starting control unit stops the partial function of the control device, it periodically starts the partial function of the control device and judges the state of the battery.

5. The control device as claimed in claim 1, wherein, The starting control unit maintains the electrical connection between the battery and the predetermined load by keeping the DC-DC converter in a charging / discharging state and keeping the relay in a conducting state.

6. The control device as claimed in claim 1, wherein, While maintaining the state of electrically connecting the battery and the predetermined load, the control unit of one party repeatedly starts and stops at predetermined intervals and judges the state of the battery.

7. The control device according to any one of claims 1 to 6, wherein, The control device is mounted on the vehicle. The starting control unit performs circuit control based on the state of the battery and transitions between starting and stopping states from the time the ignition switch of the vehicle is turned off until it is turned on.

8. A control method, performed by the control device of claim 1, which controls the power supply from a storage battery to a predetermined load via a circuit. The control method includes the following steps: The step of obtaining the state of the battery after the control device is started; The step of determining whether the state of the battery is such that it can supply power to the predetermined load; The step of controlling the circuit while maintaining electrical connection between the battery and the predetermined load, provided that the battery is in a state capable of supplying power to the predetermined load; and The step of stopping a portion of the function of the control device after the circuit has been controlled in a manner that maintains the electrical connection between the battery and the predetermined load.

9. A recording medium recording a control program, said control program being executed by a computer of the control device of claim 1, which controls the power supply from a storage battery to a predetermined load via circuitry. The control procedure includes the following steps: The step of obtaining the state of the battery after the control device is started; The step of determining whether the state of the battery is such that it can supply power to the predetermined load; The step of controlling the circuit while maintaining electrical connection between the battery and the predetermined load, provided that the battery is in a state capable of supplying power to the predetermined load; and The step of stopping a portion of the function of the control device after the circuit has been controlled in a manner that maintains the electrical connection between the battery and the predetermined load.

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