JP2010098477A - Electronic control device and method for controlling the electronic control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic control device which reduces consumption of power when entering a sleep state. <P>SOLUTION: The electronic control device includes: a sleep state switching means; a recording means; and a failure determining means. The sleep state switching means determines whether or not the device can enter a sleep state by communicating with the other electronic control devices, and enters the sleep state when it is possible. The recording means records a communication state with the other electronic control devices after a connection is made with a network. The failure determining means determines whether or not there is a failure in the communication with the other electronic control devices. When the failure determining means determines a failure and a communication record exists in the recording means, the sleep state switching means sets the sleep state after a first predetermined time has elapsed. When the failure determining means determines a failure and no communication records exist in the recording means, the sleep state switching means sets the sleep state after a second predetermined time has elapsed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic control device and a control method for the electronic control device, and more particularly, to an electronic control device having an operation state that consumes less power than a normal state, and a control method for the electronic control device.

Conventionally, a plurality of ECUs (Electronic Control Units) that can be switched between a normal state and a sleep state that consumes less power than the normal state are connected to a network, and each ECU (node) communicates with each other so that the self can There is an ECU that determines whether it is possible to transition to the sleep state and, if possible, transitions to the sleep state. For example, in the apparatus described in Patent Document 1, each ECU mounted on a vehicle transmits a frame indicating whether or not to allow transition to a sleep state to other ECUs via a network. Each ECU refers to a frame transmitted from another ECU and determines whether or not it can sleep. Specifically, each ECU transmits a frame in which a value indicating whether or not the other ECU sleeps is set at a bit position predetermined for each ECU to the other ECU. Each ECU refers to a value set in a predetermined bit position indicating whether or not to allow sleep in a frame transmitted from another ECU, and only when all ECUs are allowed to sleep, Transition own operation state to sleep state. As a result, the operating states can be matched when the operating states must be matched among the ECUs. Further, when power is supplied from a battery or the like, power consumption can be reduced by putting each ECU in a sleep state.
JP 2004-254043 A

  However, the technique described in Patent Document 1 has the following problems. That is, in general, there may be a mixture of ECUs that perform communication with each other when the vehicle ignition is OFF and ECUs that do not perform communication with each other on the same network. For example, when there is only one ECU that performs mutual communication on the same network, the ECU that performs mutual communication waits until a signal indicating whether sleep is possible or not is received from another ECU when the ignition of the vehicle is OFF. . In this case, since the other ECUs do not communicate with each other and do not transmit a sleep enable / disable signal, the ECUs that perform the mutual communication wait for a predetermined time and then transition themselves to the sleep state. Therefore, there is a problem that it takes time to transition to the sleep state and consumes unnecessary power.

  Therefore, an object of the present invention is to provide an electronic control device that consumes less power when transitioning to a sleep state.

  The present invention employs the following configuration in order to solve the above problems. That is, the first invention is an electronic control device that communicates with another electronic control device connected to the network by being connected to the network, the sleep state switching means, the recording means, An abnormality determination means. When the sleep state switching means determines whether it is possible to switch its own operation state to a sleep state with less power consumption than the normal state by communicating with the other electronic control device. The own operation state is switched to the sleep state. The recording unit records a communication state with the other electronic control device after being connected to the network. The abnormality determination unit determines whether or not there is an abnormality in communication with the other electronic control device. The sleep state switching means determines that the abnormality determination means determines that there is an abnormality, and the recording means records a communication state with the other electronic control device after the first predetermined time has elapsed. Switch to the sleep state. Further, the sleep state switching means is determined when the abnormality determining means determines that there is an abnormality and the recording means does not record the communication state with the other electronic control device or when the abnormality determining means is abnormal. When it is determined that there is none, the mode is switched to the sleep state after the elapse of a second predetermined time shorter than the first predetermined time.

  According to the present invention, when switching to the sleep state, the electronic control device determines a communication state with another electronic control device and determines whether or not there is a communication record with the other electronic control device. The sleep state switching means determines that it is in an abnormal state only when communication with another electronic control device is impossible and there is a communication record with another electronic control device. Switch to sleep after a certain amount of time. In addition, the sleep state switching means cannot communicate with other electronic control devices and there is no communication record with other electronic control devices, or communication with other electronic control devices is not possible. If it is possible, it is determined that the state is normal, and the state is switched to the sleep state after a second predetermined time shorter than the first predetermined time. As a result, when there is only one electronic control device on the same network that communicates with each other when switching to the sleep state, unnecessary waiting time can be reduced when switching to the sleep state, and power consumption is reduced. can do. That is, the electronic control device changes the time until switching to the sleep state depending on whether it is in a normal state or an abnormal state. In an abnormal state, the electronic control device switches to the sleep state after a relatively long predetermined time has elapsed. On the other hand, the electronic control device quickly switches to the sleep state in the normal state. Here, when the ignition of the vehicle is ON, if there is only one electronic control device that performs mutual communication on the same network, there is no other electronic control device that can communicate with the electronic control device, so the sleep When switching to a state, the abnormality determination means for determining an abnormality in communication with another electronic control device always determines that there is a communication abnormality. However, it is possible to determine whether or not the other electronic control device exists by recording the communication state with the other electronic control device after being connected to the network by the recording means. When there is no other electronic control device, it is natural that communication with the other electronic control device cannot be performed, and therefore it can be determined that the state is normal. For this reason, it can switch to a sleep state promptly. Therefore, from the above, power consumption can be reduced at the time of transition to the sleep state.

  In the present invention, the electronic control device may be mounted on a vehicle, and the sleep state switching means may determine whether or not the sleep state can be switched when the vehicle is powered off.

  According to this configuration, unnecessary power consumption by the electronic control device can be reduced when the ignition of the vehicle is OFF.

  A second invention is a control method of an electronic control device that communicates with another electronic control device connected to the network by being connected to the network, and includes a sleep state switching step, a recording step, And an abnormality determination step. In the sleep state switching step, it is determined whether or not it is possible to switch its own operation state to a sleep state that consumes less power than the normal state by communicating with the other electronic control device. The own operation state is switched to the sleep state. In the recording step, the communication state with the other electronic control device after being connected to the network is recorded. In the abnormality determination step, it is determined whether or not there is an abnormality in communication with the other electronic control device. In the sleep state switching step, when it is determined that there is an abnormality in the abnormality determination step and there is a record of the communication state with the other electronic control device in the recording step, after the first predetermined time has elapsed. Switch to the sleep state. In the sleep state switching step, if it is determined that there is an abnormality in the abnormality determination step and there is no record of the communication state with the other electronic control device in the recording step, or if there is an abnormality in the abnormality determination step. When it is determined that there is none, the sleep mode is switched to after the second predetermined time shorter than the first predetermined time has elapsed.

  According to the present invention, when switching the electronic control device to the sleep state, it is determined whether there is a communication abnormality between the other electronic control device and itself and whether there is a communication record with the other electronic control device. . Thereby, when there is only one electronic control device that performs mutual communication on the same network, an unnecessary standby time can be reduced at the time of transition to the sleep state, and power consumption can be reduced.

  According to this invention, when switching to the sleep state, the electronic control device determines whether there is a communication abnormality between the other electronic control device and itself, and determines whether there is a communication record with the other electronic control device. can do. As a result, when there is only one electronic control device that communicates with another electronic control device on the same network, unnecessary waiting time can be reduced at the time of transition to the sleep state, thereby reducing power consumption. can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, an in-vehicle ECU network in which a plurality of electronic control devices installed in a vehicle are connected to each other via a network is assumed. First, an in-vehicle ECU network to which an electronic control device according to the present invention is connected will be described.

  FIG. 1 is a diagram illustrating a state in which a plurality of electronic control devices are connected to a network configured by communication lines. As shown in FIG. 1, in an in-vehicle ECU system 1, an engine ECU 10, a brake ECU 11, a steering ECU 12, a meter ECU 13, a door ECU 14, and an indoor lighting control ECU 15 are connected to each other via a communication line 16. Each ECU is for controlling each part of the vehicle. For example, the steering ECU 12 controls the steering. Each ECU controls the vehicle by communicating with other ECUs via a network when the vehicle is powered on (when the ignition is on). Note that the detailed operation of each ECU and the control of the vehicle by mutual communication between the ECUs are not the essence of the present invention, and thus the description thereof is omitted. Moreover, although each ECU is connected by the communication line 16, in other embodiment, you may connect by radio | wireless.

  Here, the engine ECU 10, the brake ECU 11, and the steering ECU 12 are for controlling the running of the vehicle, and do not operate when the ignition is OFF. On the other hand, the meter ECU 13, the door ECU 14, and the room lighting control ECU 15 operate even when the ignition is OFF, because the passenger opens and closes the door and the like. However, when the ignition is OFF, the engine is not operating and power is not generated. Therefore, when these ECUs operate normally, the battery power is consumed. For this reason, the ECU (meter ECU 13, door ECU 14 and indoor lighting control ECU 15) that operates even when the ignition is OFF has the following two operating states. That is, the two operating states are a normal state and a sleep state that consumes less power than the normal state. The ECU in the sleep state is in a communicable state, and immediately transitions to the normal state (wakes up) when requested by another ECU. An ECU capable of communicating even when these ignitions are OFF is referred to as an NM (Network Management) compatible ECU. On the other hand, an ECU that cannot communicate when the ignition is OFF is referred to as an NM non-compliant ECU. As shown in FIG. 1, the meter ECU 13, the door ECU 14, and the room lighting control ECU 15 are NM compatible ECUs, and the engine ECU 10, the brake ECU 11 and the steering ECU 12 are NM non-compliant ECUs.

  Each NM-compatible ECU determines whether or not it can transition to the sleep state when the ignition is OFF. Since each NM-compatible ECU may depend on other ECUs (operate in cooperation), it cannot transition to the sleep state only by its own judgment. That is, each NM corresponding ECU determines that it can transition to the sleep state only when all other ECUs can transition to the sleep state. Therefore, each NM-compatible ECU determines whether or not it can transition to the sleep state by communicating with another ECU in determining whether or not it can transition to the sleep state. Specifically, each NM-compatible ECU determines whether sleep is possible or not by transmitting and receiving NM frames to and from each other via a network.

  Each NM-adaptive ECU changes itself to the sleep state as follows. That is, each NM-compatible ECU stores information indicating whether or not the NM-compatible ECU can sleep in a predetermined bit position of the NM frame. For example, each NM-compatible ECU stores “10” (hexadecimal notation) if sleep is possible and “00” (hexadecimal notation) if sleep is not possible in a predetermined bit position of the NM frame. Then, each NM-compatible ECU transmits an NM frame storing information on whether or not it can sleep to other NM-compatible ECUs via the communication line 16. Next, the NM compatible ECU that has received the NM frame from the NM compatible ECU other than itself refers to the NM frame received via the communication line 16 and is in a state in which the NM compatible ECU other than the self can sleep. If the self is in a sleepable state, the self is shifted to the sleep state. In other embodiments, as described in the background art, information indicating whether each NM-compatible ECU permits sleep to NM-compatible ECUs other than itself is predetermined for each NM-compatible ECU. The NM frame may be transmitted by storing in the bit position. In this case, the NM corresponding ECU that has received the NM frame refers to the information stored in the predetermined bit position to determine whether another NM corresponding ECU permits the transition to its own sleep state. Judging. When all other NM-compatible ECUs permit the transition to the sleep state, the NM-compatible ECU shifts itself to the sleep state.

  Next, the operation of the electronic control device according to the present embodiment will be described with reference to FIG. FIG. 2 is a flowchart showing an operation for transition to the sleep state of the electronic control device according to the present embodiment. The processing shown in this flowchart is executed by each NM corresponding ECU.

  In step S101, the NM-compatible ECU connected to the communication line 16 records that the NM frame has been received from another NM-compatible ECU. Specifically, when an NM-compatible ECU receives an NM frame, the NM-compatible ECU records the fact that the NM frame has been received and the name of the ECU that has transmitted the NM frame in its own recording means. The recording means is, for example, a nonvolatile memory. Each NM-compatible ECU is connected to the communication line 16 when a vehicle is manufactured at a factory, for example, and starts transmission of an NM frame to other NM-compatible ECUs when the ignition is turned on. Each NM-compatible ECU records reception of NM frames from other NM-compatible ECUs. Even when the ignition is turned off, the NM-compatible ECU holds the reception record of the NM frame until the active reception record is erased. Next, the process of step S102 is executed.

  In step S102, it is determined whether the ignition of the vehicle has been turned off. While the ignition is ON (when the determination result is No), the NM-compatible ECU operates in the normal state and does not transition to the sleep state. Therefore, the determination in step S102 is repeatedly performed until the ignition is turned OFF. When the ignition is turned off (when the determination result is Yes), the process of step S103 is executed.

  In step S103, it is determined whether or not the transition to the sleep state is possible. When the ignition of the vehicle is turned off, the NM compatible ECU determines whether or not it can transition to the sleep state by transmitting and receiving NM frames to and from other NM compatible ECUs. When transition to the sleep state is possible (when the determination result is Yes), the process of step S104 is executed. When the transition to the sleep state is impossible (when the determination result is No), the process of step S103 is repeatedly executed.

  In step S104, the NM-compatible ECU transitions to a sleep standby state. The sleep standby state is a standby state until the NM-compatible ECU transitions to the sleep state. When the ignition of the vehicle is turned off, the NM compatible ECU determines whether or not it can transition to the sleep state by transmitting and receiving NM frames to and from other NM compatible ECUs. When the NM-compatible ECU determines that sleep is possible, the NM-compatible ECU does not immediately transition to the sleep state but transitions to the sleep standby state. Next, the process of step S105 is performed.

  In step S105, it is determined whether the NM-compatible ECU (self and other NM-compatible ECUs) and the communication line 16 are in a failure state. The determination as to whether or not a failure has occurred is performed by transmitting and receiving NM frames. The NM-compatible ECU transmits an NM frame and determines whether there is a response from another NM-compatible ECU. When there is a response, the NM-compatible ECU performs transmission and reception normally, and therefore determines that the NM-compatible ECU (self and other NM-compatible ECUs) and the communication line 16 are in a normal state. If there is no response, the NM-compatible ECU determines that either transmission or reception is abnormal, and at least one of the NM-compatible ECU (self and other NM-compatible ECU) or the communication line 16 is in a failure state. Is determined. When it determines with a normal state (when a determination result is No), the process of step S106 is performed. When it is determined as a failure state (when the determination result is Yes), the process of step S107 is executed.

  Note that the determination in step S105 may be performed as follows. That is, as described above, the NM-compatible ECU determines whether it is possible to shift to the sleep state by transmitting / receiving the NM frame to / from another NM-compatible ECU in step S103. In the determination of whether or not the transition to the sleep state is possible, if the NM-compatible ECU cannot transmit and receive NM frames with other NM-compatible ECUs, the NM-compatible ECU (self and other NM-compatible ECUs) or the communication line 16 It can be determined that it is a failure state. Therefore, the NM-compatible ECU stores the failure state in the determination of whether or not the sleep state can be changed (processing in step S103), and in step S105, the failure state is referred to by referring to the stored state. A determination may be made.

  In step S106, since the NM-compatible ECU is in a normal state, it transitions to a sleep state. Here, the NM-compatible ECU does not immediately transition to the sleep state, but transitions to the sleep state after a predetermined short time has elapsed. For example, the NM-compatible ECU transitions to the sleep state after 1.5 seconds after transitioning to the sleep standby state. In this way, frequent transition to the sleep state can be prevented by making a transition to the sleep state after a predetermined short period of time without immediately transitioning to the sleep state. In step S106, the NM-compatible ECU may immediately transition to the sleep state.

  In step S107, the NM corresponding ECU determines whether or not an NM frame has been received from the connected network. If an NM frame has been received (when the determination result is Yes), the process of step S108 is executed next. If no NM frame has been received (if the determination result is No), then the process of step S106 is executed. In step S107, the NM-compatible ECU refers to the reception record of the NM frame recorded in the recording unit in step S101. If there is a reception record, it determines that the NM frame has been received, and there is no reception record. Determines that no NM frame has been received. If no NM frame has been received, it can be seen that there has been no other NM-compatible ECU on the same network in the past. FIG. 3 is an explanatory diagram showing a case where only one NM-compatible ECU is connected in one network. As shown in FIG. 3, the door ECU 14 is an NM-compatible ECU, and only one door ECU 14 is connected in the same network. Since the door ECU 14 shown in FIG. 3 does not receive NM frames from other NM-compatible ECUs after being connected to the communication line 16, there is no NM frame reception record. Therefore, if the determination result in step S107 is No, it is natural that there is no response from other NM-compatible ECUs in the determination of the failure state in step S105, and the NM-compatible ECU is in a normal state. The process of S106 is executed.

  On the other hand, if an NM frame has been received, it can be seen that another NM-compatible ECU has existed on the same network in the past (state shown in FIG. 1). Therefore, if the determination result is Yes in step S107, there is no response from the other NM-compatible ECUs even though other NM-compatible ECUs existed on the same network in the past. It can also be seen that the communication line 16 is in a faulty state. Therefore, in this case, the process of step S108 is executed next.

  In step S108, the NM-compatible ECU (self or another NM-compatible ECU) or the communication line 16 is in a failure state, and thus transitions to a sleep state after a predetermined time has elapsed. Since the NM-compatible ECU cannot communicate with other NM-compatible ECUs, it cannot grasp the state of the other NM-compatible ECUs. In such a case, if the NM-compatible ECU immediately transitions to the sleep state, an unexpected problem (for example, that the other NM-compatible ECU is in the sleep state) depends on its own operation. There is a possibility that a problem such as a problem of disturbing the control to be shifted to wakes up and waking up may occur. Therefore, the NM-compatible ECU does not immediately transition to the sleep state, but transitions to the sleep state after a predetermined long time (a time longer than the standby time in step S106) has elapsed. For example, the NM-compatible ECU transitions to the sleep state after 60 seconds have elapsed since the transition to the sleep standby state.

  As described above, when it is determined in step S105 that the failure state has occurred, it is determined whether or not the determination of the failure state in step S105 is correct by determining whether or not an NM frame has been received in the past (step S107). It is possible to judge whether it is an error. Thereby, unnecessary power consumption can be suppressed in the transition to the sleep state. For example, when there is only one NM-compatible ECU on the same network as shown in FIG. 3, it is always determined as a failure state in the determination of the failure state in step S105. When the process of step S107 is not executed, the NM-compatible ECU waits for 60 seconds and transitions to the sleep state despite being in the normal state. Accordingly, by determining whether or not the determination of the failure state is correct in step S107, unnecessary standby time can be reduced and power consumption can be reduced.

  Note that the process of step S107 may be executed between step S104 and step S105. FIG. 4 is a flowchart showing a modification of the process shown in FIG. In FIG. 4, the same step numbers are assigned to the same processes as in FIG. As shown in FIG. 4, after the processing from step S101 to step S104 is executed, the processing of step S107 is executed. If the determination result in step S107 is Yes (if an NM frame has been received), the process of step S105 is executed to determine the failure state. If the determination result in step S107 is No (when no NM frame has been received), there is no other NM compatible ECU in the first place, and it is not necessary to determine the failure state of the other NM compatible ECU. The process proceeds to step S106 without performing the process in step S105.

  As described above, in the present invention, power consumption can be reduced at the time of transition to the sleep state, and for example, it can be used as an electronic control device mounted on a vehicle.

The figure which showed a mode that several electronic control units were connected to the network comprised by the communication line The flowchart which shows the operation | movement for the transition to the sleep state of the electronic control apparatus which concerns on this embodiment. Explanatory drawing showing a case where only one NM-compatible ECU is connected in one network The flowchart which showed the modification of the process shown by FIG.

Explanation of symbols

1 On-vehicle ECU system 10 Engine ECU
11 Brake ECU
12 Steering ECU
13 Meter ECU
14 Door ECU
15 Indoor lighting control ECU
16 communication line

Claims (3)

An electronic control device that communicates with another electronic control device connected to the network by being connected to the network,
It is determined whether or not it is possible to switch its own operating state to a sleep state that consumes less power than the normal state by communicating with the other electronic control unit. Sleep state switching means for switching to the sleep state;
Recording means for recording a communication state with the other electronic control device after being connected to the network;
An abnormality determining means for determining whether there is an abnormality in communication with the other electronic control device;
The sleep state switching means includes
When the abnormality determining means determines that there is an abnormality and there is a record of the communication state with the other electronic control device in the recording means, the sleep state is switched to after the first predetermined time,
When the abnormality determining means determines that there is an abnormality and there is no record of the communication state with the other electronic control device in the recording means, or when the abnormality determining means determines that there is no abnormality, An electronic control device, wherein the electronic control device switches to the sleep state after a second predetermined time shorter than one predetermined time. The electronic control device is mounted on a vehicle,
The electronic control device according to claim 1, wherein the sleep state switching unit determines whether or not it is possible to switch to the sleep state when the vehicle is powered off. A control method of an electronic control device that communicates with another electronic control device connected to the network by being connected to the network,
It is determined whether it is possible to switch its operation state to a sleep state that consumes less power than the normal state by communicating with the other electronic control device, and if it is determined that it is possible, A sleep state switching step for switching to the sleep state;
A recording step of recording a communication state with the other electronic control device after being connected to the network;
An abnormality determination step for determining whether there is an abnormality in communication with the other electronic control device,
In the sleep state switching step,
When it is determined that there is an abnormality in the abnormality determination step and there is a record of a communication state with the other electronic control device in the recording step, the sleep state is switched to after the first predetermined time has elapsed,
When it is determined that there is an abnormality in the abnormality determination step and there is no record of the communication state with the other electronic control device in the recording step, or when it is determined that there is no abnormality in the abnormality determination step, A control method for an electronic control device, wherein a switch is made to the sleep state after elapse of a second predetermined time shorter than the first predetermined time.

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