In-vehicle system and ecu

Abstract

To provide a technique for easily suppressing wasteful power consumption of an ECU.SOLUTION: The on-vehicle system 1 includes a ECU12 mounted in the vehicle, and an on-vehicle management device 20 communicable with the ECU12. An on-vehicle management device 20 switches a relay 13 for switching a power supply state to a ECU12 to an ON state when a start condition is satisfied, and transmits a start instruction signal to the ECU12. When the relay 13 is switched to the ON state, the ECU12 is supplied with power and is switched from the power-off state to the activated state. The ECU12 maintains the start state when receiving the start instruction signal within a determination time after switching to the start state, and transmits a cutoff permitting signal to the on-vehicle management device 20 when not receiving the start instruction signal within the determination time. When receiving the cutoff permission signal, the on-vehicle management device 20 switches the relay 13 to the OFF state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an in-vehicle system and an ECU. [Background technology]

[0002] Patent Document 1 discloses a configuration in which a switch is provided between a battery and an ECU. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-192108 Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration of Patent Document 1, the ECU can be switched between a power-off state and a power-on state by switching the on / off state of the switch. However, with the configuration of Patent Document 1, even if the switch is accidentally switched to the on state, the ECU switches to the power-on state, which raises concerns about the ECU wasting power.

[0005] The present disclosure provides a technique that makes it easy to reduce unnecessary power consumption in an ECU. [Means for solving the problem]

[0006] The in-vehicle system of the present disclosure includes: An ECU installed in a vehicle; an in-vehicle management device capable of communicating with the ECU; the in-vehicle management device switches a relay for switching a power supply state to the ECU to an ON state when a startup condition is satisfied, and transmits a startup instruction signal to the ECU; When the relay is switched to the on state, the ECU receives power supply and switches from a power-off state to an activated state, and when the activation instruction signal is received within a determination time after switching to the activated state, the ECU maintains the activated state, while when the activation instruction signal is not received within the determination time, the ECU transmits a cutoff permission signal to the in-vehicle management device; When the on-board management device receives the cutoff permission signal, the on-board management device switches the relay to an OFF state.

[0007] The ECU of the present disclosure is When power is supplied, the device switches to an activated state, and if a startup instruction signal is received from the vehicle-mounted management device within a determination time after switching to the activated state, the device maintains the activated state, but if the startup instruction signal is not received within the determination time, the device switches to a sleep state. [Effects of the Invention]

[0008] According to the technology of the present disclosure, it is easy to reduce unnecessary power consumption of the ECU. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an in-vehicle system according to the first embodiment. [Figure 2] FIG. 2 is a flowchart showing the flow of processing performed by the vehicle-mounted management device of the first embodiment. [Figure 3] FIG. 3 is a flowchart showing the flow of processing performed by the ECU of the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Description of the embodiments of the present disclosure] First, embodiments of the present disclosure will be listed and described.

[0011] [1] An ECU installed in a vehicle; an in-vehicle management device capable of communicating with the ECU; the in-vehicle management device switches a relay for switching a power supply state to the ECU to an ON state when a startup condition is satisfied, and transmits a startup instruction signal to the ECU; When the relay is switched to the on state, the ECU receives power supply and switches from a power-off state to an activated state, and when the activation instruction signal is received within a determination time after switching to the activated state, the ECU maintains the activated state, while when the activation instruction signal is not received within the determination time, the ECU transmits a cutoff permission signal to the in-vehicle management device; When the on-board management device receives the cutoff permission signal, the on-board management device switches the relay to an off state. In-vehicle systems.

[0012] The above-mentioned in-vehicle system can supply power to the ECU by switching the relay to an ON state when a startup condition is met, thereby switching the ECU from a power-off state to an activated state. The in-vehicle management device can maintain the ECU in an activated state by sending a startup instruction signal to the ECU that has switched to the activated state. In contrast, if the relay is erroneously switched to an ON state, the in-vehicle management device does not send a startup instruction signal to the ECU. In this case, after the ECU switches to the activated state, the in-vehicle management device sends a cut-off permission signal to the in-vehicle management device after a determination time has elapsed. As a result, the in-vehicle management device switches the relay to an OFF state, and the ECU enters a power-off state. Therefore, the above-mentioned in-vehicle system can switch the ECU to a power-off state when the relay is erroneously switched to an ON state, thereby reducing unnecessary power consumption by the ECU.

[0013] [2] If the ECU does not receive the activation instruction signal within the determination time, the ECU transmits the shutdown permission signal to the vehicle management device and then transitions to a sleep state. The in-vehicle system described in [1].

[0014] In some cases, a relay that has been erroneously switched on may not return to its off state. Even in such a case, the ECU transitions to a sleep state, which consumes less power, thereby reducing power consumption.

[0015] [3] When the on-board management device receives the cutoff permission signal, the on-board management device switches the relay to the off state on the condition that it is determined that the relay can be switched to the off state based on the vehicle state. An in-vehicle system according to [1] or [2].

[0016] Even in such a case, the ECU may erroneously transmit a cutoff permission signal. In this case, the vehicle management device switches the relay to the off state only when it determines that the relay can be switched to the off state based on the vehicle state, so it is easy to avoid switching the relay to the off state in a situation where it should not be switched to the off state.

[0017] [4] The vehicle-mounted management device has a first control unit that controls the relay and a second control unit that communicates with the ECU, The first control unit and the second control unit are configured to be able to operate independently of each other. An in-vehicle system according to any one of [1] to [3].

[0018] In the above-mentioned in-vehicle system, even if the first control unit fails, the second control unit can transition the ECU into a sleep state, and even if the second control unit fails, the first control unit can switch the relay to an off state.

[0019] [5] When power is supplied, the device switches to an activated state, and if a startup instruction signal is received from the vehicle management device within a determination time after switching to the activated state, the device maintains the activated state, but if the startup instruction signal is not received within the determination time, the device switches to a sleep state. ECU.

[0020] Even if the ECU switches to the active state due to the relay being erroneously switched on, the ECU switches to the sleep state by not receiving the activation instruction signal, thereby reducing unnecessary power consumption by the ECU.

[0021] [Details of the embodiments of the present disclosure] First Embodiment <1-1. Configuration of In-Vehicle System 1> 1 is a system mounted on a vehicle. The vehicle system 1 includes a power supply unit 10, a power line 11, an ECU 12, a relay 13, a bus 14, and an on-board management device 20.

[0022] The power supply unit 10 includes, for example, a battery. The power supply unit 10 may include, for example, a low-voltage battery, or may include a high-voltage battery and a DC-DC converter that steps down the output voltage of the high-voltage battery.

[0023] The power path 11 is an electrical path that supplies power from the power supply unit 10 to the ECU 12 .

[0024] The ECU 12 is an electronic control unit. The ECU 12 is electrically connected to the power path 11.

[0025] The relay 13 may be configured as a mechanical switch or a semiconductor switch. The relay 13 is provided between the power supply unit 10 and the ECU 12 in the power path 11. The relay 13 switches the state of power supply to the ECU 12. Specifically, when the relay 13 is in the ON state, it allows power to be supplied from the power supply unit 10 to the ECU 12, and when the relay 13 is in the OFF state, it cuts off the power supply from the power supply unit 10 to the ECU 12. In other words, when the relay 13 is in the ON state, power is supplied to the ECU 12, and when the relay 13 is in the OFF state, the power supply to the ECU 12 is cut off.

[0026] The in-vehicle management device 20 is a device that manages the power supply state of the ECU 12. The in-vehicle management device 20 includes a communication unit 21, a state determination unit 22, a first control unit 23, and a second control unit 24.

[0027] The communication unit 21 is configured by, for example, a communication interface. The communication unit 21 is a communication interface that enables the in-vehicle management device 20 to communicate with the ECU 12 via the bus 14. The communication unit 21 is, for example, a transceiver, and more specifically, a CAN transceiver.

[0028] The state determination unit 22, the first control unit 23, and the second control unit 24 can operate independently of each other. For example, the state determination unit 22, the first control unit 23, and the second control unit 24 are configured as separate control circuits each including a microcomputer.

[0029] The state determination unit 22 determines the vehicle state based on various information input thereto. The state determination unit 22 transmits state information indicating the determined vehicle state to the first control unit 23 and the second control unit 24.

[0030] The first control unit 23 determines whether the activation condition is met based on the state information received from the state determination unit 22, and switches the relay 13 to the ON state if it is determined that the activation condition is met. The first control unit 23 stores, for example, a table indicating the correspondence between the vehicle state and the ON / OFF state of its own control object (e.g., the relay 13). The first control unit 23 determines the control object to be turned ON based on this table and the vehicle state. Determining the control object to be turned ON in this way corresponds to determining that the activation condition for the control object is met.

[0031] The second control unit 24 is capable of communicating with the ECU 12 via the bus 14. The second control unit 24 determines whether or not a start condition is met based on the state information received from the state determination unit 22, and when it determines that the start condition is met, it transmits a start instruction signal to the ECU 12 via the bus 14. The second control unit 24 determines whether or not the start condition is met, for example, in the same manner as the first control unit 23 described above. The second control unit 24 transmits the activation instruction signal at the timing when the ECU 12 switches to the activated state and becomes able to receive signals.

[0032] When the relay 13 is in the off state, the ECU 12 is not supplied with power and is therefore in a power-off state. When the relay 13 is switched to the on state, the ECU 12 receives power from the power path 11 and switches to a power-on state. When the relay 13 is switched to the on state, the ECU 12 transitions between an active state and a sleep state. The sleep state consumes less power than the active state. When the relay 13 is switched to the on state, the ECU 12 switches to the active state. If the ECU 12 receives a start-up instruction signal within a predetermined determination time, the ECU 12 maintains the active state. However, if the ECU 12 does not receive the start-up instruction signal within the determination time, the ECU 12 transmits a cut-off permission signal to the second control unit 24. If the ECU 12 does not receive the start-up instruction signal within the determination time, the ECU 12 transmits the cut-off permission signal to the second control unit 24 and then transitions to the sleep state.

[0033] When the second control unit 24 receives the cut-off permission signal, it transmits the cut-off permission signal to the state determination unit 22. When the state determination unit 22 receives the cut-off permission signal, it transmits the cut-off permission signal to the first control unit 23. When the first control unit 23 receives the cut-off permission signal, it determines whether or not the relay 13 can be switched to the off state based on the state information. When the relay 13 should be switched to the off state based on, for example, the above-mentioned table and the vehicle state, the first control unit 23 determines that the relay 13 can be switched to the off state. When the first control unit 23 determines that the relay 13 can be switched to the off state, it switches the relay 13 to the off state.

[0034] <1-2. Example of Operation of In-Vehicle Management Device 20> The in-vehicle management device 20 performs the processing shown in Fig. 2, for example. In step S11, the in-vehicle management device 20 determines whether a predetermined activation condition is met. If the in-vehicle management device 20 determines that the activation condition is not met, it determines in step S14 whether a shutdown permission signal has been received. If the in-vehicle management device 20 determines that a shutdown permission signal has not been received, it returns to the processing of step S11. In other words, the in-vehicle management device 20 repeats the processing of step S11 and step S14 until the activation condition is met or the shutdown permission signal is received.

[0035] If the in-vehicle management device 20 determines in step S11 that the activation condition is met, the in-vehicle management device 20 switches the relay 13 to the ON state in step S12, and transmits an activation instruction signal to the ECU 12 in step S13. Thereafter, the process shown in FIG. 2 ends.

[0036] If the vehicle management device 20 determines in step S14 that it has received the cutoff permission signal, it determines in step S15 whether or not it is in a state where cutoff is possible. If the vehicle management device 20 determines that it is not in a state where cutoff is possible, it ends the processing shown in Fig. 2 without switching the relay 13 to the off state. If the vehicle management device 20 determines that it is in a state where cutoff is possible, it switches the relay 13 to the off state in step S16 and ends the processing shown in Fig. 2. The vehicle management device 20 repeatedly executes the processing shown in Fig. 2 by restarting it immediately after completing the processing shown in Fig. 2.

[0037] <1-3. Example of ECU12 operation> When receiving power supply from the power path 11, the ECU 12 starts, for example, the process shown in FIG. 3. In step S21, the ECU 12 determines whether the state has been switched to the activated state. The ECU 12 repeats the process of step S21 until the state has been switched to the activated state. If the ECU 12 determines that the state has been switched to the activated state, in step S22, the ECU 12 determines whether a start instruction signal has been received. If the ECU 12 determines that the start instruction signal has not been received, in step S24, the ECU 12 determines whether a determination time has elapsed since the state was switched to the activated state. If the ECU 12 determines that the determination time has not elapsed, the ECU 12 returns to the process of step S22. That is, the ECU 12 repeats the process of step S22 and step S24 until the start instruction signal is received or the determination time has elapsed. If the ECU 12 determines that the start instruction signal has been received, the ECU 12 ends the process shown in FIG. 3 while maintaining the activated state in step S23. If the ECU 12 determines that the determination time has elapsed, it transmits a cutoff permission signal to the vehicle management device 20 in step S25, and transitions to a sleep state in step S26. Thereafter, the ECU 12 ends the process shown in FIG.

[0038] <1-4. Examples of the Actions and Effects of the In-Vehicle System 1> The in-vehicle system 1 includes an ECU 12 mounted on a vehicle and an in-vehicle management device 20 capable of communicating with the ECU 12. When a start-up condition is met, the in-vehicle management device 20 switches a relay 13, which switches the state of power supply to the ECU 12, to an on state and transmits a start-up instruction signal to the ECU 12. When the relay 13 switches to the on state, the ECU 12 receives power and switches from a power-off state to an activated state. If the ECU 12 receives a start-up instruction signal within a determination time after switching to the activated state, the ECU 12 maintains the activated state, but if the ECU 12 does not receive the start-up instruction signal within the determination time, it transmits a shut-off permission signal to the in-vehicle management device 20. When the in-vehicle management device 20 receives the shut-off permission signal, it switches the relay 13 to an off state.

[0039] When a start condition is satisfied, the in-vehicle system 1 supplies power to the ECU 12 by switching the relay 13 to an ON state, thereby switching the ECU 12 from a power-off state to an activated state. The in-vehicle management device 20 can maintain the ECU 12 in the activated state by transmitting a start instruction signal to the ECU 12 that has switched to the activated state. In contrast, if the relay 13 is erroneously switched to an ON state, the in-vehicle management device 20 does not transmit a start instruction signal to the ECU 12. In this case, the ECU 12 transmits a cutoff permission signal to the in-vehicle management device 20 after a determination time has elapsed since the ECU 12 switched to the activated state. As a result, the in-vehicle management device 20 switches the relay 13 to an OFF state, and the ECU 12 enters a power-off state. Therefore, when the relay 13 is erroneously switched to an ON state, the in-vehicle system 1 can switch the ECU 12 to a power-off state, thereby reducing unnecessary power consumption by the ECU 12.

[0040] If the ECU 12 does not receive the activation instruction signal within the determination time, it transmits a shutoff permission signal to the in-vehicle management device 20 and then transitions to a sleep state. It may also occur that the relay 13, which has been erroneously switched to the on state, does not return to the off state. For example, if an on-failure occurs in which the relay 13 is stuck in the on state, the relay 13 does not return to the off state. Even in such a case, the ECU 12 transitions to a sleep state with lower power consumption, thereby reducing power consumption.

[0041] When the on-board management device 20 receives the cut-off permission signal, the on-board management device 20 switches the relay 13 to the off state on the condition that it is determined based on the vehicle state that the relay 13 can be switched to the off state. It is possible that the cut-off permission signal is erroneously transmitted from the ECU 12. Even in this case, the on-board management device 20 switches the relay 13 to the off state on the condition that it is determined based on the vehicle state that the relay 13 can be switched to the off state, making it easy to avoid switching the relay 13 to the off state in a situation where it should not be switched to the off state.

[0042] The in-vehicle management device 20 has a first control unit 23 that controls the relay 13 and a second control unit 24 that communicates with the ECU 12, and the first control unit 23 and the second control unit 24 are configured to be able to operate independently of each other. With this configuration, even if the first control unit 23 fails, the in-vehicle system 1 can cause the second control unit 24 to transition the ECU 12 to a sleep state, and even if the second control unit 24 fails, the first control unit 23 can switch the relay 13 to an off state.

[0043] <Other embodiments> The present disclosure is not limited to the embodiments described above and in the drawings. For example, any combination of features of the above-described or following embodiments is possible within a range that does not contradict. Furthermore, any feature of the above-described or following embodiments may be omitted unless explicitly stated as essential. Furthermore, the above-described embodiment may be modified as follows.

[0044] The ECU does not need to transition to a sleep state after transmitting the cutoff permission signal.

[0045] The on-board management device 20 may switch the relay to the OFF state when it receives the cutoff permission signal, regardless of the vehicle state.

[0046] The state determination unit, the first control unit, and the second control unit do not have to be able to operate independently of each other. For example, the state determination unit, the first control unit, and the second control unit may be configured by a control circuit including a single microcomputer.

[0047] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is not limited to the embodiments disclosed herein, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0048] 1. In-vehicle systems 10...Power supply section 11…Power line 12...ECU 13...Relay 14...Bus 20…In-vehicle management device 21…Communications Department 22...Status determination unit 23...First control section 24...Second control section

Claims

1. An ECU mounted on a vehicle; an in-vehicle management device capable of communicating with the ECU; the in-vehicle management device switches a relay for switching a power supply state to the ECU to an ON state when a startup condition is satisfied, and transmits a startup instruction signal to the ECU; When the relay is switched to the on state, the ECU receives power supply and switches from a power-off state to an activated state, and when the activation instruction signal is received within a determination time after switching to the activated state, the ECU maintains the activated state, while when the activation instruction signal is not received within the determination time, the ECU transmits a cutoff permission signal to the in-vehicle management device; When the on-board management device receives the cutoff permission signal, the on-board management device switches the relay to an off state. In-vehicle systems.

2. If the ECU does not receive the activation instruction signal within the determination time, the ECU transmits the shutdown permission signal to the vehicle management device and then transitions to a sleep state. The in-vehicle system according to claim 1 .

3. When the on-board management device receives the cutoff permission signal, the on-board management device switches the relay to the off state on the condition that it is determined that the relay can be switched to the off state based on the vehicle state.

3. The in-vehicle system according to claim 1.

4. the in-vehicle management device has a first control unit that controls the relay and a second control unit that communicates with the ECU; The first control unit and the second control unit are configured to be able to operate independently of each other.

3. The in-vehicle system according to claim 1.

5. When power is supplied, the device switches to an activated state, and if a startup instruction signal is received from the vehicle management device within a determination time after switching to the activated state, the device maintains the activated state, but if the startup instruction signal is not received within the determination time, the device switches to a sleep state. ECU.

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