JP5598430B2 - Power supply control system, power supply control device, and power supply control method - Google Patents

Description

  The present invention relates to a power supply control system, a power supply control apparatus, and a power supply control method that can individually switch supply / cutoff of power from a power supply to a plurality of electronic devices that communicate via a common communication line.

  Conventionally, a vehicle is equipped with a plurality of electronic devices such as an ECU (Electronic Control Unit), and each electronic device operates cooperatively while exchanging information via a network such as a CAN (Controller Area Network). The control related to the traveling of the vehicle, the control related to the comfort of the vehicle interior, and the like are realized. Each electronic device is connected to a power source such as a vehicle battery or an alternator via a power line, and is operated by power supplied from the power source. In recent years, since the number of electronic devices mounted on vehicles has increased, power saving has been demanded.

  In Patent Document 1, a control power source that generates a second power source from a first power source in response to an input of a first start signal by a switch input or a second start signal from a communication line, and a first start signal When activated in response to the first activation mode, it operates in the first operation mode. When activated in response to the second activation signal, it operates in the second operation mode. There has been proposed an electronic control device having a device control circuit that outputs a shutdown signal for stopping the generation of. This electronic control device can stop the power supply to the control circuit even when activated in response to a signal input via the communication line.

JP 2007-133729 A

  As in the electronic control device described in Patent Document 1, the power consumption can be reduced by stopping the power supply from the power source. However, in a system in which a plurality of electronic devices communicate via a network, each electronic device transmits data periodically and does not receive data from another device for a predetermined period of time. There is a configuration in which it is determined that occurrence has occurred. The electronic device that has been determined that an abnormality has occurred performs a special operation in the event of an abnormality such as stopping processing or issuing a warning. In the system having such a configuration, when the power supply to some of the plurality of electronic devices connected to the network is stopped, the power supply is stopped for the electronic devices that are not stopped. Since data from the electronic device is not received, it is determined that an abnormality has occurred. Since the electronic device that is determined to have an abnormality performs a special operation at the time of the abnormality, the normal operation expected as the system may not be performed.

  Therefore, in the case of the system having the above-described configuration, it is necessary to stop power supply to the electronic devices all at once for all the electronic devices connected via the network, and it is possible to stop all the electronic devices. Since the possible conditions are limited, there is a problem that a sufficient power consumption reduction effect cannot be obtained. Or, when the power supply to some electronic devices is stopped, the processing of each electronic device is changed so as to exclude this electronic device from the judgment target of occurrence of abnormality based on the presence or absence of received data. Although it is possible to stop power supply to some electronic devices by taking measures, there is a problem that processing cannot be easily performed because it is necessary to change the processing contents of all electronic devices connected to the network. is there.

  The present invention has been made in view of such circumstances, and an object of the present invention is to individually switch power supply / cutoff to each electronic device for a plurality of electronic devices connected to the network. It is an object to provide a power control system, a power control device, and a power control method.

  A power supply control system according to the present invention includes a communication unit that is connected to a common communication line, periodically transmits data to the communication line, and receives data periodically transmitted from another device. A plurality of electronic devices having detection means for detecting a communication abnormality when periodic data from the device is not received for a predetermined period, and control for individually switching power supply / interruption from the power source to each electronic device In a power supply control system comprising a power supply control device having a switch control means, the switch control means of the power supply control device cuts off power to the electronic device for a period shorter than the predetermined period. It is characterized by that.

  Further, in the power supply control system according to the present invention, the switching control means repeatedly performs power cutoff for a predetermined cutoff period and supply of power for a predetermined return period. The total of the return periods is shorter than the predetermined period.

  The power supply control system according to the present invention is characterized in that the return period is longer than a period in which the electronic device can perform at least one data transmission from the start of power supply.

  Further, the power supply control device according to the present invention includes a switching control unit that performs control for individually switching supply / cutoff of power from the power supply to each electronic device for a plurality of electronic devices connected to a common communication line. In the power supply control device provided, the switching control means cuts off the power to the electronic device for a time shorter than a period of detecting a communication abnormality when the electronic device does not receive data from another device. It is characterized by being.

  Further, the power supply control method according to the present invention includes a communication unit that is connected to a common communication line, periodically transmits data to the communication line, and receives data periodically transmitted from other devices, and For a plurality of electronic devices having detection means for detecting a communication abnormality when periodic data from other devices is not received over a predetermined period, supply / cutoff of power from the power source to each electronic device is individually performed. In the power supply control method for switching, the power to the electronic device is cut off for a period shorter than the predetermined period.

  In the present invention, for a plurality of electronic devices connected to a common communication line, the power supply control device individually switches supply / cutoff of power from the power supply to each electronic device. However, in order to prevent the periodic data transmission by the electronic device from being cut off due to the power interruption, the power supply control device only supplies power to the electronic device for a period shorter than a predetermined period for detecting an abnormality when there is no data reception. Shut off. After the elapse of this period, the power supply control device controls switching so that electric power is supplied to the electronic device, whereby the operation of the electronic device is started and periodic data transmission is performed. Therefore, the other electronic device can receive data from the electronic device whose power is temporarily interrupted before detecting the abnormality.

  Moreover, in this invention, a power supply control apparatus performs repeatedly the interruption | blocking of the electric power over the interruption | blocking period, and the electric power supply over a return period. At this time, the sum of the interruption period and the return period is shorter than a predetermined period during which the electronic device detects an abnormality. Thereby, before another electronic device detects an abnormality, it is possible to restore the electronic device from which power was cut off, to perform data transmission, and to reduce power consumption while repeating cut-off and restoration. Can do.

  In the present invention, the return period for returning the electronic device after power interruption is longer than the period during which the electronic device that has started supplying power can perform at least one data transmission. Accordingly, since the restored electronic device can perform data transmission at least once, data from the electronic device can be received by other electronic devices before the abnormality is detected.

  In the case of the present invention, the power to the electronic device is cut off for a period shorter than a predetermined period in which an abnormality is detected when there is no data reception, so that the other communication line is connected to the common communication line. Since it is possible to individually switch power supply / interruption to the electronic device without the abnormality being detected by the electronic device, it is possible to more effectively reduce the power consumption of the entire system.

It is a block diagram which shows the structure of the power supply control system which concerns on this invention. It is a block diagram which shows the structure of a power switch apparatus and a power supply control apparatus. It is a block diagram which shows the structure of ECU. It is a schematic diagram for demonstrating the intermittent control which a power supply control apparatus performs. It is a flowchart which shows the procedure of the process which a power supply control apparatus performs. It is a block diagram which shows the structure of the power supply control system which concerns on a modification. It is a block diagram which shows the structure of ECU which concerns on a modification.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. FIG. 1 is a block diagram showing a configuration of a power supply control system according to the present invention. In the figure, reference numeral 1 denotes a power supply device such as a battery and an alternator mounted on the vehicle. A power supply device 1 mounted on a vehicle is connected to a power switch device 2, a power supply control device 3, ECUs 5a and 5b and the like mounted on the vehicle via a power line 7, and supplies power to these devices. . The ECUs 6 a and 6 b mounted on the vehicle are not directly connected to the power supply device 1 but are connected to the power switch device 2 via individual power lines, and the power supply device is connected via the power switch device 2. Power from 1 is supplied. The power switch device 2 can individually switch the supply / cutoff of power to the ECUs 6 a and 6 b in accordance with a control signal given from the power control device 3. The ECUs 5 a, 5 b and 6 a, 6 b are connected by a common communication line 8 and can communicate with each other via the communication line 8.

  FIG. 2 is a block diagram showing configurations of the power switch device 2 and the power control device 3. The power switch device 2 includes a switching unit 21 having a plurality of switches arranged in the power supply path from the power device 1 to each of the ECUs 6a and 6b, and an input unit 22 to which a control signal from the power control device 3 is input. The switch of the switching unit 21 can be switched on / off according to a control signal input to the input unit 22. For example, the switching unit 21 of the power switch device 2 has N switches, and the power control device 3 outputs an N-bit control signal. The power switch device 2 associates a switch with each bit of the control signal. It can be configured to switch on / off.

  The power supply control device 3 includes a control unit 31, an output unit 32, an input unit 33, a storage unit 34, a power supply circuit 35, and the like. The control unit 31 is an arithmetic circuit such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), and relates to power control by reading and executing a program stored in advance in a ROM (Read Only Memory) or the like. Various processes are performed. The output unit 32 outputs a control signal to the power switch device 2 according to the control of the control unit 31, and is an interface circuit or an output buffer.

  The input unit 33 receives various vehicle information from other devices mounted on the vehicle (for example, the state of an ignition switch or accessory switch for starting the vehicle engine, the traveling speed of the vehicle, the position of the shift lever, the operating state of the brake, etc. Etc.) and the inputted vehicle information is given to the control unit 31. The control unit 31 individually determines whether or not to supply power to the ECUs 6 a and 6 b based on the vehicle information given from the input unit 33, and outputs a control signal to the power switch device 2. The input unit 33 may be configured to acquire vehicle information from another device by performing communication via the communication line 8.

  The storage unit 34 includes a data rewritable memory element such as an EEPROM (Electrically Erasable Programmable ROM) or a flash memory, and stores various data necessary for the control of the control unit 31. The power supply circuit 35 is connected to the vehicle power supply device 1 via the power line 7 and supplies the power from the power supply device 1 to each part in the power supply control device 3 by appropriately adjusting the voltage value / current value. .

  FIG. 3 is a block diagram showing the configuration of the ECU 6a. The other ECUs 5a, 5b, and 6b have substantially the same configuration as that of the ECU 6a, and are not shown. The ECU 6a includes a control unit 61, a communication unit 62, a power supply circuit 63, and the like. The control unit 61 is an arithmetic circuit such as a CPU or MPU, and performs various processes related to vehicle control by reading and executing a program stored in advance in a ROM or the like. The communication unit 62 is connected to the communication line 8 and communicates with other ECUs 5a, 5b, 6b and the like mounted on the vehicle using a protocol such as CAN or LIN. The power supply circuit 63 is connected to a power line, and supplies the power supplied via the power line by appropriately adjusting the voltage value / current value to each part in the ECU 6a.

  In the power supply control system according to the present embodiment, a plurality of ECUs 5a, 5b and 6a, 6b, etc. share information by communicating via the communication line 8, and operate in a coordinated manner so that the vehicle can travel safely. Various control processes are implemented to prevent crimes and improve comfort in the vehicle. However, it is not always necessary that all the ECUs 5a, 5b and 6a, 6b mounted on the vehicle are in operation. For example, the ECU for the keyless entry, smart entry or security system of the vehicle does not need to operate while the vehicle is running. For example, when the engine of the vehicle is stopped, ABS (Anti-lock Brake System) etc. The ECU related to the travel control does not need to operate. Therefore, in the power supply control system according to the present embodiment, it is necessary to determine whether the ECUs 6a, 6b, etc. need to operate based on the vehicle information input to the input unit 33 by the power supply control device 3, respectively. By stopping the power supply to the ECUs 6a, 6b, etc. that are determined to be absent, the power consumption of the entire vehicle is reduced.

  On the other hand, when an abnormality such as a failure occurs in any of the plurality of ECUs 5a, 5b and 6a, 6b connected to the common communication line 8, the data from the ECU cannot be received. Therefore, there is a possibility that other ECUs cannot perform normal processing. Since safety is important in vehicles, it is necessary for other ECUs to detect a failure of one of the ECUs as soon as possible and to deal with the abnormality. Therefore, in the power supply control system according to the present embodiment, the plurality of ECUs 5a, 5b and 6a, 6b connected to the common communication line 8 are within a predetermined cycle (which may be different for each ECU). In addition, at least once data transmission is performed and whether or not there is an abnormality is determined according to whether or not data periodically transmitted from another ECU is received.

  Here, when the power supply control device 3 determines that the power supply to the ECU 6a is stopped and outputs a control signal to the power supply switch device 2, the power supply device 1 supplies power to the ECU 6a by the switching unit 21 of the power supply switch device 2. A switch provided in the route is turned off. As a result, the power supply to the ECU 6a is stopped (the power supply is cut off), and the operation of the ECU 6a is stopped. Therefore, the periodical data transmission by the ECU 6a is not performed during the period when the power supply is cut off. Since the other ECUs 5a, 5b and 6b cannot receive data to be transmitted periodically from the ECU 6a whose power is cut off, the ECU 5a determines that an abnormality has occurred in the ECU 6a, and shifts to a process when the abnormality occurs.

  Therefore, the power supply control device 3 according to the present embodiment intermittently powers off the ECUs 6a and 6b, thereby preventing the other ECUs 5a and 5b from proceeding to processing when an abnormality occurs. FIG. 4 is a schematic diagram for explaining intermittent control performed by the power supply control device 3, and shows data transmission of the ECU 6a and power control for the ECU 6a as a timing chart. As shown in the upper part of FIG. 4, the ECU 6a periodically transmits data, and the other ECUs 5a, 5b, and 6b operate normally depending on whether or not the periodic data from the ECU 6a is received. Determine whether it is operating.

  For example, when the processing of the ECU 6a is stopped for some reason and the periodic data transmission is stopped, the other ECUs 5a, 5b, and 6b receive a predetermined time from the last data reception from the ECU 6a (communication interruption determination time≈transmission of the ECU 6a). When the communication interruption is detected after the (period) elapses and data is not received from the ECU 6a even after a predetermined time (standby time) has elapsed, it is determined that an abnormality has occurred in the ECU 6a. That is, the other ECUs 5a, 5b, and 6b determine the abnormality of the ECU 6a after a predetermined abnormality determination time (= communication interruption determination time + standby time) has elapsed since the last data reception from the ECU 6a. In other words, the ECU 6a may perform data transmission at least once within the abnormality determination time by the other ECUs 5a, 5b, and 6b.

  As shown in the middle part of FIG. 4, when the condition for shutting off the power supply of the ECU 6 a is established, the power supply control device 3 shuts off the power supply of the ECU 6 a for a predetermined time (cutoff time T1), and then the predetermined time (return time T2). The power supply of the ECU 6a is repeatedly conducted over the range. The return time T2 is set to be longer than the time required from the start of power supply to the ECU 6a until the end of at least one data transmission. Further, the total time of the shut-off time T1 and the return time T2, that is, the power control cycle for the ECU 6a is determined to be shorter than the above-described abnormality determination time, and the shut-off time T1 is determined therefrom.

  The power supply control device 3 stores in advance a shut-off time T1 and a return time T2 for performing intermittent control in the storage unit 34 for each ECU 6a, 6b to be controlled. When the power supply control device 3 repeatedly performs the power shutdown for the cutoff time T1 and the power conduction for the return time T2, as shown in the lower part of FIG. 4, at least 1 within the abnormality determination time of the other ECUs 5a, 5b and 6b. Since the ECU 6a can perform data transmission once, the other ECUs 5a, 5b, and 6b can continue to perform normal processing.

  FIG. 5 is a flowchart showing a procedure of processing performed by the power supply control device 3. In the illustrated process, a cutoff flag in which one of ON / OFF values is set is used. This flag is used as a variable in a storage area such as a register in the control unit 31 of the power supply control device 3 or the storage unit 34. Secured. The initial value of the cutoff flag is off. Similarly, a cutoff timer is used in the illustrated process, but this may be provided in the control unit 31. The illustrated process is performed individually for each of the ECUs 6a and 6b to be controlled, and the same process is repeated for each controlled object. Below, it demonstrates as a process with respect to ECU6a.

  First, the control unit 31 of the power supply control device 3 determines whether or not a condition for stopping the power supply of the ECU 6a (cutting off the power supply) is established based on the vehicle information input from another device by the input unit 33. Is determined (step S1). When the interruption condition is satisfied (S1: YES), the control unit 31 further determines whether or not the value of the interruption flag is set to OFF (step S2). When the value of the shutoff flag is set to off (S2: YES), the control unit 31 sets the value of the shutoff flag to on (step S3), starts counting by the shutoff timer (step S4), The process proceeds to step S5. When the value of the cutoff flag is set to ON (S2: NO), the control unit 31 continues to count the cutoff timer and advances the process to step S5.

  Next, the control unit 31 determines whether or not the value of the cutoff timer is equal to or longer than the cutoff time T1 (step S5). When the value of the shut-off timer is less than the shut-off time T1 (S5: NO), the control unit 31 outputs a control signal for turning off the switch related to power supply to the ECU 6a to the power switch device 2, thereby turning off the power of the ECU 6a. (Step S6), the interruption timer is continuously counted, and the process returns to step S1. The ECU 6a whose power is cut off stops its operation.

  When the value of the cutoff timer is equal to or greater than the cutoff time T1 (S5: YES), the control unit 31 further determines whether or not the value of the cutoff timer is equal to or greater than the total time of the cutoff time T1 and the return time T2 (step S7). When the value of the cutoff timer is less than the total time of the cutoff time T1 and the return time T2 (S7: NO), the control unit 31 outputs a control signal for turning on the switch relating to the power supply to the ECU 6a to the power switch device 2. By doing so, power supply conduction of ECU6a is performed (step S8), time-measurement of the interruption | blocking timer is continued, and a process is returned to step S1. The ECU 6a to which the power is turned on starts (returns) the operation and transmits data.

  When the value of the cutoff timer is equal to or greater than the total time of the cutoff time T1 and the return time T2 (S7: YES), the control unit 31 clears (sets to 0) the value of the cutoff timer (step S9) and supplies power to the ECU 6a. Blocking is performed (step S6), and the process returns to step S1. The ECU 6a whose power is cut off stops its operation.

  If the shut-off condition is not satisfied in step S1 (S1: NO), the control unit 31 sets the value of the shut-off flag to off (step S10), and stops counting the shut-off timer (step S11). Thereafter, the control unit 31 outputs a control signal for turning on the switch relating to the power supply to the ECU 6a to the power switch device 2, thereby conducting the power supply of the ECU 6a (step S12), and the process returns to step S1. The ECU 6a to which the power is turned on starts its operation.

  The power supply control system having the above configuration is configured such that the power supply control device 3 shuts off the power supply of the ECUs 6a and 6b only for a time shorter than the time when the other ECUs 5a and 5b determine abnormality. Therefore, it is possible to individually switch the power supply / cutoff of the ECUs 6a and 6b without detecting an abnormality in the ECU 6a. Therefore, the power supply to the ECUs 6a and 6b can be stopped to reduce the power consumption of the entire system. it can. Further, the power supply control device 3 repeats the power interruption for the interruption time T1 and the power restoration for the restoration time T2, and the sum of the interruption time T1 and the restoration time T2 is made shorter than the abnormality determination time by the other ECUs 5a and 5b. Thus, before the other ECUs 5a and 5b detect the abnormality, the ECUs 6a and 6b that cut off the electric power can be restored, the ECUs 6a and 6b can transmit data, and the consumption is repeated while the interruption and restoration are repeated. Electric power can be reduced. The return time T2 is set to a period longer than the period during which the ECUs 6a and 6b that have started supplying power can perform at least one data transmission, so that the restored ECUs 6a and 6b perform at least one data transmission. Therefore, the data from the ECUs 6a and 6b can be received by the other ECUs 5a and 5b before the abnormality is detected.

  In the present embodiment, the power switch device 2 and the power control device 3 are separate devices. However, the present invention is not limited to this, and these may be a single device, and further to the following modifications. As shown, the functions of the power switch device 2 and the power control device 3 may be mounted on any ECU.

(Modification)
FIG. 6 is a block diagram illustrating a configuration of a power supply control system according to a modification. The power control system according to the modification has a configuration in which the functions of the power switch device 2 and the power control device 3 shown in FIG. 1 are mounted on an ECU 103 such as a body ECU, for example. For this reason, the ECU 103 performs control processing as an ECU such as vehicle door lock control or light lighting control, and also performs power supply / cutoff switching control processing from the power supply device 1 to the ECUs 6a and 6b as described above. Do.

  FIG. 7 is a block diagram showing a configuration of the ECU 103 according to the modification. The ECU 103 according to the modification includes a switching unit 21 similar to the power switch device 2, a control unit 31, an input unit 33, a storage unit 34, and a power circuit 35 similar to the power control device 3. However, the switching unit 21 of the ECU 103 is directly controlled to turn on / off each switch by a control signal output from the control unit 31. The control unit 31 of the ECU 103 performs control processing such as door lock control or light lighting control in addition to intermittent power control processing performed by the control unit 31 of the power control device 3.

DESCRIPTION OF SYMBOLS 1 Power supply device 2 Power switch device 3 Power supply control device 5a, 5b ECU
6a, 6b ECU (electronic device)
7 power line 8 communication line 21 switching unit 22 input unit 31 control unit (switching control means)
32 Output unit 33 Input unit 34 Storage unit 35 Power supply circuit 61 Control unit (detection means)
62 Communication part (communication means)
63 Power supply circuit 103 ECU

Claims (5)

A communication means connected to a common communication line, periodically transmitting data to the communication line and receiving data periodically transmitted from another device, and periodic data from the other device for a predetermined period A plurality of electronic devices having detection means for detecting a communication abnormality when not received over a power supply, and a power supply control device having switching control means for performing control for individually switching supply / cutoff of power from the power supply to each electronic device, In a power supply control system comprising:
The power supply control system, wherein the switching control means of the power supply control device cuts off power to the electronic device for a period shorter than the predetermined period. The switching control means is configured to repeatedly cut off power over a predetermined cut-off period and supply power over a predetermined return period,
The power supply control system according to claim 1, wherein a total of the blocking period and the return period is shorter than the predetermined period. The power supply control system according to claim 2, wherein the return period is longer than a period in which the electronic device can perform data transmission at least once from the start of power supply. In a power supply control device comprising a switching control means for performing control for individually switching supply / cutoff of power from a power supply to each electronic device for a plurality of electronic devices connected to a common communication line,
The switching control means cuts off power to the electronic device for a time shorter than a period of detecting a communication abnormality when the electronic device does not receive data from another device. Power supply control device. A communication means connected to a common communication line, periodically transmitting data to the communication line and receiving data periodically transmitted from another device, and periodic data from the other device for a predetermined period In the power supply control method for individually switching the supply / cutoff of power from the power supply to each electronic device for a plurality of electronic devices having detection means for detecting a communication abnormality when not received over
The power supply control method, wherein power to the electronic device is cut off for a period shorter than the predetermined period.

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