Electronic control unit

Abstract

To provide an electronic control device capable of determining the presence or absence of an abnormality in a power supply line with an optimally simplified configuration.SOLUTION: A boost circuit 13 boosts a power supply voltage VB supplied from an external power source through a plurality of power supplying lines 19. A power source voltage monitor 11a detects a power source voltage VB supplied to the plurality of power supplying lines 19. A microcomputer 11 operates the boost circuit 13 in different states and determines the presence of abnormality in the power supplying line 19 when the amount of change in the power source voltage VB detected by the power source voltage monitor 11a exceeds a predetermined abnormality determination threshold value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an electronic control device for detecting an abnormality in a power supply line.

Background Art

[0002] Conventionally, a control device for detecting an abnormality in a power line has been proposed (see, for example, Patent Document 1). According to the control device described in Patent Document 1, a first power line and a second power line connected to an external power supply, and a current inspection unit for detecting a disconnection of the first power line are provided, and the second power line becomes automatically usable when the first power line is disconnected. According to the configuration described in this Patent Document 1, by providing a first current inspection unit in a first power supply line that supplies a power supply voltage to the control device, it is possible to detect a disconnection of the first power supply line.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technology described in the background art section, in order to detect a disconnection of the power supply line, it is necessary to add a current inspection unit composed of other circuits of the booster circuit, such as a shunt resistor, a comparator, etc., and it becomes necessary to provide a current inspection unit.

[0005] An object of the present disclosure is to provide an electronic control device capable of determining the presence or absence of an abnormality in a power supply line with a configuration as simple as possible.

Means for Solving the Problems

[0006] According to claim 1, the booster circuit boosts the power supply voltage supplied from a plurality of power supply lines, and the power supply voltage monitor detects the power supply voltage supplied to the plurality of power supply lines. Booster circuitOnly the following was operated. A predetermined first state at that time and Unlike the first state, the boost circuit is not activated. A predetermined second state Between that time and that time, The abnormality detection unit determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage detected by the power supply voltage monitor exceeds a predetermined abnormality detection threshold. According to claim 2, in a single driving cycle, between a first state in which the boost circuit is operated when the power is turned on and a second state in which it is operated during the shutdown process, which is different from the first state, the abnormality determination unit determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage detected by the power supply voltage monitor exceeds a predetermined abnormality determination threshold. Therefore, Claim 1 or 2 According to the description, a boost circuit can be used to determine whether or not there is an abnormality. As a result, a current testing unit for determining the presence or absence of abnormalities becomes unnecessary, and the presence or absence of abnormalities in the power supply line can be determined with the simplest possible configuration. [Brief explanation of the drawing]

[0007] [Figure 1] Electrical configuration diagram of the electronic control device in the first embodiment [Figure 2] Flowchart illustrating the processing content in the first embodiment [Figure 3] Flowchart illustrating the processing content in the second embodiment [Figure 4] Time chart showing the change in signals or states of each part in the second embodiment [Figure 5] Flowchart illustrating the processing details in the third embodiment [Figure 6] Time chart showing the change in signals or states of each part in the third embodiment [Figure 7] Flowchart illustrating the processing content in the fourth embodiment [Figure 8] Time chart showing the change in signals or states of each part in the fourth embodiment [Modes for carrying out the invention]

[0008] Several embodiments of the electronic control device will be described below with reference to the drawings. In the embodiments described below, the same or similar reference numerals may be used for components that are the same or similar in each embodiment, and their descriptions may be omitted.

[0009] (First Embodiment) The first embodiment will be described with reference to Figures 1 and 2. The electronic control device 10 shown in Figure 1 comprises a microcontroller 11, a voltage divider circuit 12, a boost circuit 13, a drive circuit 14, and a drive circuit 15.

[0010] The electronic control unit 10 is supplied with a power supply voltage VB from an external power supply 18 through multiple power supply lines 19. The power supply lines 19 supply the power supply voltage VB to the electronic control unit 10 through the harness and the power input terminals of the electronic control unit 10. Multiple power supply lines 19 are connected between the external power supply 18 and the electronic control unit 10, taking into account the effects of some disconnections D (see Figure 1) caused by aging.

[0011] The voltage divider circuit 12 is configured, for example, by connecting voltage divider resistors 12a and 12b in series between the power supply voltage VB and ground nodes, thereby dividing the power supply voltage VB. The microcontroller 11 is equipped with a power supply voltage monitor 11a, which monitors the power supply voltage VB divided by the voltage divider circuit 12. The microcontroller 11 is equipped with non-volatile and volatile memory 11b to store various programs and data.

[0012] The boost circuit 13 generates a boosted voltage Vbo by boosting the power supply voltage VB. The boost circuit 13 comprises a coil 21, a switch 22, a diode 23, a smoothing capacitor 24, a capacitor 25, a shunt resistor 26, and a control circuit 27 in the illustrated configuration.

[0013] Switch 22 is an n-channel field-effect transistor. Smoothing capacitor 24 is connected between the power supply voltage VB and the ground node. Between the power supply voltage VB and the ground node, in order from the power supply node side of VB, coil 21, the drain-source connection of switch 22, and shunt resistor 26 are connected in series. The anode of diode 23 is connected to the common connection point of the drains of coil 21 and switch 22.

[0014] A capacitor 25 is connected to the cathode of the diode 23. A control circuit 27 is connected to the gate terminal of the switch 22. The control circuit 27 controls the on / off of the switch 22 according to the control signal from the microcomputer 11. The boost voltage monitor 27a monitors the boost voltage Vbo stored in the capacitor 25 of the boost circuit 13, and the microcomputer 11 receives this monitoring result. The boost current monitor 27b monitors the voltage at the connection point between the switch 22 and the shunt resistor 26, and the microcomputer 11 receives this monitoring result.

[0015] The control circuit 27 charges the capacitor 25 by repeatedly performing the on / off control of the switch 22. Normally, the control circuit 27 sets the boost operation mode to the normal mode M1. In this case, the control circuit 27 controls the voltage applied to the gate terminal of the switch 22 so as to obtain a predetermined boost current value Io, and sets the voltage at which the charging of the capacitor 25 is completed to the charging completion voltage Vo, and repeatedly performs the on / off control of the switch 22.

[0016] Specifically, when the control circuit 27 turns on the switch 22, current flows through the path of the coil 21, the switch 22, and the shunt resistor 26. When the value of the boost current monitor 27b exceeds the predetermined boost current value Io, the control circuit 27 turns off the switch 22. Then, a back electromotive force is generated in the coil 21, and the back electromotive voltage of this coil 21 is charged to the capacitor 25. The control circuit 27 monitors the boost voltage Vbo by the boost voltage monitor 27a, and repeatedly performs the on / off control of the switch 22 until the charging completion voltage Vo is reached. Thereby, in the normal mode M1, the boost voltage Vbo stored in the capacitor 25 is charged until it reaches the charging completion voltage Vo.

[0017] The drive circuit 14 is connected to the supply node of the boost voltage Vbo, uses the boost voltage Vbo as a power source, and drives the external load 16. The drive circuit 14 is controlled by receiving a control signal from the microcomputer 11. The drive circuit 15 is connected to the supply node of the power supply voltage VB, uses the power supply voltage VB as a power source, and drives the external load 17. The drive circuit 15 is controlled by receiving a control signal from the microcomputer 11.

[0018] Figure 2 shows the processing details of the abnormality determination of the power supply line 19 by the electronic control unit 10. The user may drive the vehicle regularly, such as once a day or several times a day, or once a week, or may drive it irregularly. The abnormality determination process shown in Figure 2 is executed when the electronic control unit 10 performs the shutdown process at the timing when the user turns off the ignition switch after driving the vehicle.

[0019] When the ignition switch is turned off, the electronic control unit 10 performs a shutdown process. When performing the shutdown process, the electronic control unit 10 executes an abnormality diagnosis of the power supply line 19. First, in step S101, the electronic control unit 10 stops all loads including the boost circuit 13. Thereby, the factors causing the drop of the power supply voltage VB can be narrowed down in the subsequent steps.

[0020] Next, in step S104, the microcomputer 11 monitors the power supply voltage VB when all loads are stopped by the power supply voltage monitor 11a. Let this monitoring result be voltage V1. Next, in step S106, the microcomputer 11 commands the control circuit 27 to operate only the boost circuit 13 for boosting. When the boost circuit 13 operates, power is consumed, so the power supply voltage VB drops. In step S108, the microcomputer 11 monitors the power supply voltage VB at this time by the power supply voltage monitor 11a. Let the monitoring result at this time be voltage V2.

[0021] In step S109, the microcomputer 11 stops the operation of the boost circuit 13 through the control circuit 27. The microcomputer 11 calculates the voltage drop amount V1 - V2 of the power supply voltage VB during the boosting operation of the boost circuit 13 in step S111. When the voltage drop amount V1 - V2 exceeds a predetermined abnormality determination threshold value, the microcomputer 11 determines that there is an abnormality in the power supply line 19 in step S112. When the voltage drop amount V1 - V2 does not exceed the predetermined abnormality determination threshold value, the microcomputer 11 ends the test process.

[0022] When some of the power supply lines 19 deteriorate and break D occurs, the combined resistance of the multiple power supply lines 19 increases. As the combined resistance increases, the drop in the power supply voltage VB V1-V2 also increases in proportion to the increase in the combined resistance. By setting a predetermined abnormality detection threshold to an appropriate predetermined value, the degree of deterioration of the power supply lines 19 and the extent of the break D can be determined.

[0023] According to this embodiment, the microcontroller 11 determines that there is an abnormality in the power supply line 19 when the change in the power supply voltage VB (= drop V1-V2) between when only the boost circuit 13 is operating and when the boost circuit 13 is not operating exceeds a predetermined abnormality determination threshold. This eliminates the need for a current test unit for abnormality diagnosis other than the configuration of the boost circuit 13, and allows for the determination of whether or not there is an abnormality in the power supply line 19 with the simplest possible configuration. The boost operation state when only the boost circuit 13 is operating corresponds to the first state, and the boost operation state when the boost circuit 13 is not operating corresponds to the second state.

[0024] (Second Embodiment) The second embodiment will be described with reference to Figures 3 and 4. The electrical configuration of the electronic control unit 10 is the same as in the first embodiment, so its description will be omitted. Figure 3 shows a flowchart in which the processes of steps S102, S103, S105, S107, and S110 are inserted into the flowchart of Figure 2 described in the first embodiment, thereby expanding the processing content. Figure 4 shows a timing chart during the execution of the processes shown in Figure 3.

[0025] The timings t101 to t112 shown in Figure 4 represent the timings for executing steps S101 to S112 in Figure 3, respectively. During the period prior to timing t101 in Figure 4, the electronic control unit 10 performs vehicle control, including boosting the voltage using the boost circuit 13 and driving external loads 16 and 17 using the drive circuits 14 and 15. As a result, the power supply voltage VB fluctuates in accordance with the load fluctuations.

[0026] Similar to the embodiment described above, the electronic control unit 10 performs a shutdown process when the vehicle's ignition switch is turned off. When the electronic control unit 10 performs the shutdown process, in step S101, it stops the boosting operation of the boost circuit 13 and also stops all loads that use the power supply voltage VB. Therefore, the fluctuation of the power supply voltage VB stops during the period from timing t101 in Figure 4 onwards.

[0027] Next, in step S102 of Figure 3, the microcontroller 11 operates the drive circuit 14 to discharge the boosted voltage Vbo. After timing t102 in Figure 4, the drop slope of the boosted voltage Vbo increases and the boosted voltage Vbo drops significantly, but the power supply voltage VB remains largely unchanged.

[0028] In step S103, the microcontroller 11 changes the boost operation mode from normal mode M1 to abnormal detection mode M2. Details of abnormal detection mode M2 ​​will be described later. During this time, the microcontroller 11 operates the drive circuit 14 to continuously discharge the boosted voltage Vbo.

[0029] Next, in step S104, the microcontroller 11 monitors the power supply voltage VB when the boost operation by the boost circuit 13 is stopped using the power supply voltage monitor 11a. The monitoring result of the power supply voltage VB at timing t104 in Figure 4 is denoted as voltage V1.

[0030] Next, in step S105 of Figure 3, the microcontroller 11 stops the drive circuit 14 that was operated in step S102. Refer to the fact that the control state of the drive circuit 14 changes from on to off at timing t105 in Figure 4.

[0031] Next, in step S106 of Figure 3, the microcontroller 11 commands the control circuit 27 to operate the boost circuit 13 in a boosting operation. The microcontroller 11 operates the boost circuit 13 in abnormality detection mode M2. The microcontroller 11 operates the boost circuit 13 in a boosting operation until it reaches an abnormality detection charge completion voltage Vo2, which is greater than the charge completion voltage Vo of the boost voltage Vbo of the boost circuit 13 during normal vehicle control. Furthermore, the microcontroller 11 operates the boost circuit 13 in a boosting operation using an abnormality detection boost current value Io2, which is greater than the boost current value Io during normal vehicle control. The boost current value Io2 indicates the amplitude of the boost pulse that the control circuit 27 applies to the switch 22 during boost control.

[0032] Here, we show a configuration in which both the charge completion voltage Vo2 and the boost current value Io2 are set to be greater than the charge completion voltage Vo and boost current value Io under normal vehicle control conditions, but this is not the only configuration. For example, only the charge completion voltage Vo2 or only the boost current value Io2 may be set to be greater than the values ​​under normal vehicle control conditions. This allows the boost circuit 13 to operate with different settings under conditions more suitable for abnormal diagnosis than under normal vehicle control conditions in abnormal detection mode M2. As a result, the reliability of abnormal diagnosis can be further improved.

[0033] As shown in Figure 4 from timing t106 onwards, when the boost circuit 13 operates, it consumes power, so the power supply voltage VB drops and the boosted voltage Vbo gradually increases. Next, in step S107 in Figure 3, the microcontroller 11 operates the drive circuit 15, increasing the amount of drop in the power supply voltage VB. As shown in Figure 4 from timing t107 onwards, the power supply voltage VB drops further. Next, in step S108, the microcontroller 11 monitors the power supply voltage VB with the power supply voltage monitor 11a. The monitoring result of the power supply voltage VB at timing t108 in Figure 4 is denoted as voltage V2.

[0034] In step S109 in Figure 3, the microcontroller 11 stops the boost operation of the boost circuit 13 via the control circuit 27. At timing t109 in Figure 4, the output of the boost pulse of the boost circuit 13 is stopped.

[0035] The microcontroller 11 stops the operation of the drive circuit 15 in step S110 in Figure 3. At timing t110 in Figure 4, the control state of the drive circuit 15 transitions from on to off.

[0036] In step S111 of Figure 3, the microcontroller 11 calculates the voltage drop V1-V2 of the power supply voltage VB during operation of the boost circuit 13. See timing t111 in Figure 4. If the voltage drop V1-V2 exceeds a predetermined abnormality threshold, the microcontroller 11 determines in step S112 that there is an abnormality in the power supply line 19. See timing t112 in Figure 4. In step S111 of Figure 3, if the voltage drop V1-V2 does not exceed the predetermined abnormality threshold, the microcontroller 11 terminates the abnormality determination process.

[0037] <Summary of this embodiment> According to this embodiment, when the microcontroller 11 determines an abnormality in the power supply line 19, in abnormality detection mode M2, it uses an abnormality detection boost current value Io2, which is larger than the boost current value Io used during normal vehicle control, to boost the voltage of the boost circuit 13. In abnormality detection mode M2, the boost circuit 13 consumes a larger current than during normal vehicle control when boosting the voltage. As a result, the drop in the power supply voltage VB V1-V2 when an abnormality occurs in the power supply line 19 can be increased, making it easier to detect abnormalities in the power supply line 19.

[0038] Furthermore, according to this embodiment, when the microcontroller 11 determines an abnormality in the power supply line 19, in abnormality detection mode M2, it uses a charge completion voltage Vo2 that is higher than the charge completion voltage Vo of the boost circuit 13 during normal vehicle control to boost the voltage of the boost circuit 13. By making the charge completion voltage Vo2 in abnormality detection mode M2 ​​higher than the charge completion voltage Vo during normal vehicle control, the microcontroller 11 can extend the boost operation time of the boost circuit 13. As a result, the time during which the power supply voltage VB experiences a voltage drop can be extended. Consequently, a longer time can be secured for determining whether or not there is an abnormality in the power supply line 19.

[0039] When the microcontroller 11 determines whether there is an abnormality in the power supply line 19 by the boost operation of the boost circuit 13, it is desirable to maximize the boost voltage range that the boost circuit 13 increases. In this embodiment, when the microcontroller 11 determines an abnormality in the power supply line 19, the drive circuit 14 connected to the boost circuit 13 is operated in advance to discharge the boost voltage Vbo of the boost circuit 13 from the normal charge completion voltage Vo before the boost circuit 13 is operated.

[0040] The microcontroller 11 pre-activates the drive circuit 14 to discharge the boosted voltage Vbo of the boost circuit 13, thereby intentionally creating a state where the boosted voltage Vbo is significantly lower than the normal charge completion voltage Vo. By activating the drive circuit 14, the microcontroller 11 can quickly create this low boosted voltage Vbo state, minimizing the waiting time before diagnosis can begin.

[0041] In this embodiment, the drive circuit 15 connected to multiple power supply lines 19 is operated while the boost circuit 13 is performing its boost operation. The drive circuit 15 consumes a large current, which increases the voltage drop of the power supply voltage VB and makes it easier to detect abnormalities in the power supply lines 19.

[0042] (Third embodiment) The third embodiment will be described with reference to Figures 5 and 6. The difference between the third embodiment and the first embodiment is that the presence or absence of abnormality in the power supply line 19 is determined using the moving average value of the power supply voltage VB drop. The differences from the first or second embodiment will be described, and the descriptions of other parts will be omitted as necessary.

[0043] Figure 5 shows a flowchart illustrating the process executed when, for example, the electronic control unit 10 is shut down, and Figure 6 shows a timing chart representing the moving average value of the drop amount V1-V2, which changes with each execution of the process shown in Figure 5. The processing content of steps S101, S102, S104, S105, S107, and S108 shown in Figure 5 is the same as in the first embodiment.

[0044] In steps S104 and S107, the microcontroller 11 obtains voltages V1 and V2, which are the voltages V1 and V2 obtained by monitoring the power supply voltage VB. In step Sa, it stores the voltage drop amounts V1-V2 in the non-volatile memory 11b. In step Sb, the microcontroller 11 reads past voltage drop amounts V1-V2 from the non-volatile memory 11b, and in step Sc, it calculates the moving average value of the voltage drop amounts V1-V2. At this time, the microcontroller 11 reads a predetermined number of voltage drop amounts V1-V2 from the memory 11b going back in time and calculates the average value.

[0045] In S111a, the microcontroller 11 determines whether the moving average value of the drop amounts V1-V2 exceeds the abnormality detection threshold C. If the moving average value exceeds the abnormality detection threshold C in S111a, the microcontroller 11 determines that there is an abnormality in the power supply line 19.

[0046] In other words, by executing the process shown in Figure 5 each time the electronic control unit 10 shuts down, the microcontroller 11 can store the drop amounts V1-V2 in the non-volatile memory 11b and read their changes using a moving average value. Figure 6 shows that the abnormality detection process shown in Figure 5 is executed at each timing t301, t302, t303...t311.

[0047] If the vehicle's internal maintenance is performed well and the power supply line 19 has not deteriorated significantly, the voltage drop V1-V2 of the power supply voltage VB will not be large. For example, see timings t301...t304 shown in Figure 6. Therefore, even if the microcontroller 11 calculates the average value of past voltage drops V1-V2, it will not be very large and will not exceed the abnormality detection threshold C.

[0048] However, as the power supply line 19 deteriorates, the drop in power supply voltage VB V1-V2 also gradually increases, and when the average value over a predetermined number of past cycles is calculated, it gradually increases compared to before. For example, see timings t305...t310 shown in Figure 6. Furthermore, if the deterioration of the power supply line 19 progresses further and, for example, a break D occurs, the drop in power supply voltage VB V1-V2 increases, and the moving average value exceeds the abnormality detection threshold C. Then, the microcontroller 11 determines that there is an abnormality in the power supply line 19 at timing t311, when the moving average value of the drop V1-V2 exceeds the abnormality detection threshold C.

[0049] According to this embodiment, the microcontroller 11 determines that there is an abnormality in the power supply line 19 when the moving average value of the drop amount V1-V2 of the power supply voltage VB when the boost circuit 13 is operated to boost the voltage exceeds a predetermined abnormality determination threshold C. As a result, the same effects as in the previous embodiment can be obtained, and the robustness of the diagnosis can be improved.

[0050] In this embodiment, the presence or absence of an abnormality in the power supply line 19 is determined each time the electronic control unit 10 performs a shutdown process. If one cycle of turning the user's ignition switch on and off is considered one driving cycle, the moving average value of the power supply voltage VB drop V1-V2 can be calculated from at least the second driving cycle, and the presence or absence of an abnormality in the power supply line 19 can be determined.

[0051] (Fourth Embodiment) A fourth embodiment will be described with reference to Figures 7 and 8. Figure 7 shows a flowchart of the abnormality detection process for the power supply line 19, and Figure 8 shows an example of a timing chart.

[0052] At timing t401 in Figure 8, when the ignition switch is turned on by user operation, the electronic control unit 10 is powered on via the power supply line 19. In step S106a in Figure 7, the microcontroller 11 operates only the boost circuit 13 when the vehicle starts up. From timing t402 onward in Figure 8, the control circuit 27 of the microcontroller 11 gradually increases the boost voltage Vbo of the boost circuit 13 from its initial value of zero.

[0053] When powered on, the control circuit 27 increases the boosted voltage Vbo using the boosted current value Io, which is used for normal vehicle control in normal mode M1, as the amplitude of the boost pulse, and increases the boosted voltage Vbo to the charge completion voltage Vo. The microcontroller 11 generates the boosted voltage Vbo by operating only the boost circuit 13 without operating the drive circuits 14 and 15 or driving the external loads 16 and 17.

[0054] As shown in Figure 8, when the microcontroller 11 operates only the boost circuit 13 without operating the drive circuits 14 and 15, the power supply voltage VB remains approximately constant. At timing t403 in Figure 8, even if the boost voltage Vbo is still increasing to the charge completion voltage Vo, the microcontroller 11 can detect a relatively constant voltage V2a by detecting the power supply voltage VB with the power supply voltage monitor 11a.

[0055] At timing t404, which occurs during vehicle operation after timing t403, the microcontroller 11 drives external loads 16 and 17 using drive circuits 14 and 15, respectively. At this time, the power supply voltage VB fluctuates significantly. For example, consider the case where a break D occurs in some of the power supply lines 19 at timing t404 during vehicle operation.

[0056] Even if a break D occurs in some of the power supply lines 19, the power supply voltage VB is supplied to the electronic control unit 10 through the other power supply lines 19. Subsequently, when the ignition switch is turned off by user operation, the microcontroller 11 performs a shutdown process.

[0057] Subsequently, during the shutdown process, the microcontroller 11 operates only the boost circuit 13 via the control circuit 27 in step S106b of Figure 7. Then, in step S108b of Figure 7, the microcontroller 11 monitors the power supply voltage VB as voltage V2b using the power supply voltage monitor 11a. See timing t405 in Figure 8.

[0058] In step S111 of Figure 7, the microcontroller 11 determines whether the drop in the power supply voltage VB, V2a-V2b, exceeds the abnormality detection threshold. If the microcontroller 11 determines that the drop in V2a-V2b exceeds the abnormality detection threshold, it determines that there is an abnormality in the power supply line 19 in step S112 of Figure 7. Refer to the abnormality detection result of the power supply line 19 at timing t406 in Figure 8.

[0059] According to this embodiment, the microcontroller 11 determines the power supply voltage VB detected when it operates the boost circuit 13 during power-on and shutdown processes as voltage V2a and voltage V2b, respectively. Here, the boost operation state of the boost circuit 13 during power-on corresponds to a predetermined first state, and the boost operation state of the boost circuit 13 during shutdown processes corresponds to a predetermined second state. The microcontroller 11 determines that there is an abnormality in the power supply line 19 when this voltage drop V2a-V2b exceeds a predetermined abnormality determination threshold. Therefore, it is possible to determine whether or not there is an abnormality in the power supply line 19 using the boost circuit 13, achieving the same effect as in the previously described embodiment.

[0060] <Comparative Example> For example, the microcontroller 11 could monitor the power supply voltage VB after each shutdown process of a driving cycle and determine the amount of voltage drop VB between two shutdown processes of driving cycles.

[0061] At this time, the microcontroller 11 determines that there is an abnormality in the power supply line 19 if the amount of the drop exceeds a predetermined abnormality detection threshold. In this method, if the microcontroller 11 determines that there is an abnormality in the power supply line 19 in the second driving cycle, it can display a warning on a display (not shown) or notify the user through the speaker when the power is turned on in the third driving cycle.

[0062] <Effects of this embodiment> In this embodiment, the microcontroller 11 can calculate the drop in the power supply voltage VB, V2a-V2b, detected by the power supply voltage monitor 11a at power-on and shutdown during one driving cycle. Therefore, the microcontroller 11 can determine whether or not there is an abnormality in the power supply line 19 within one driving cycle, and can display a warning on a display (not shown) or notify the user of the warning through the speaker at power-on during the second driving cycle. Therefore, the time until a warning is issued can be shortened compared to the technology of the comparative example.

[0063] (Other embodiments) This disclosure is not limited to the embodiments described above, and can be modified or expanded as shown below, for example. The electronic control unit 10 can be started not only when the vehicle is started in response to the user's operation of the ignition switch or the like, but also automatically at a predetermined timing using the soak timer built into the electronic control unit 10. The predetermined timing here is, for example, a predetermined period of time after the last vehicle start, such as a certain number of hours or a certain number of days.

[0064] Thus, the system may be configured to perform a check for abnormalities in the power supply line 19 each time it is activated by the soak timer. The electronic control unit 10 may also perform the same processing as in the above embodiment when it is activated by the soak timer. That is, the microcontroller 11 monitors the power supply voltage VB when the boost circuit 13 is at its initial boost voltage Vbo = zero using the power supply voltage monitor 11a and sets it to voltage V1. The microcontroller 11 then monitors the power supply voltage VB when it is approximately constant after the boost circuit 13 has been activated as voltage V2, and detects the difference between the power supply voltage drop V1-V2. If this drop V1-V2 exceeds the abnormality detection threshold, it is determined that there is an abnormality in the power supply line 19.

[0065] When the electronic control unit 10 is started by the soak timer, the time required for shutdown can be shortened compared to when the power is turned on based on the user's ignition switch operation. Therefore, when started by the soak timer, the shutdown process can be shortened compared to the shutdown process during normal vehicle control. As a result, the current consumption required for abnormality detection processing of the power supply line 19 can be reduced. By using the soak timer to synchronize the timing of the diagnosis, robust diagnosis that is not affected by driving conditions becomes possible.

[0066] This case includes the invention described in the claims, as well as the following inventions: [1] A boost circuit (13) that increases the power supply voltage supplied from an external power source through multiple power supply lines, A power supply voltage monitor (11a) for detecting the power supply voltage supplied to the plurality of power supply lines, An abnormality determination unit (11) determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage detected by the power supply voltage monitor exceeds a predetermined abnormality determination threshold when the boost circuit is operated in a predetermined first state and when it is operated in a predetermined second state different from the first state, An electronic control device equipped with the following features.

[0067] [2] The abnormality determination unit determines that there is an abnormality in the power supply line when the amount of change in the power supply voltage between when only the boost circuit is operated and when the boost circuit is not operated exceeds a predetermined threshold [1].

[0068] [3] An electronic control device [1] or [2] comprising an abnormality detection mode in which, when the abnormality determination unit determines an abnormality in the power supply line, the control circuit uses an abnormality detection boost current value that is larger than the boost current value used during normal vehicle control to boost the boost circuit.

[0069] [4] An electronic control device according to any one of [1] to [3], wherein when the abnormality determination unit determines an abnormality in the power supply line, the control circuit has an abnormality detection mode in which it uses an abnormality determination charge completion voltage that is greater than the charge completion voltage of the boost circuit during normal vehicle control to boost the boost circuit.

[0070] [5] An electronic control device according to any one of the items [1] to [4], wherein when the abnormality determination unit determines an abnormality in the power supply line, it operates a circuit connected to the boost circuit in advance to discharge the boosted voltage of the boost circuit before operating the boost circuit.

[0071] [6] An electronic control device according to any one of [1] to [5], wherein when the abnormality determination unit determines an abnormality in the power supply line, the circuit connected to the plurality of power supply lines is operated while the boost circuit is performing a boost operation.

[0072] [7] The abnormality determination unit determines that there is an abnormality in the power supply line when the moving average value of the amount of drop in the power supply voltage when the boost circuit is operated to boost the voltage exceeds a predetermined abnormality determination threshold, according to any one of the electronic control devices described in [1] to [6].

[0073] [8] The abnormality determination unit determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage between the time the boost circuit is boosted during power-on and shut-off in a single driving cycle exceeds the abnormality determination threshold, as described in any of [1] to [7].

[0074] [9] The abnormality determination unit determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage when the boost circuit is boosted each time it is started by the soak timer exceeds the abnormality determination threshold. [1] to [8]

[0075] The electronic control unit 10 and its method described herein may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. Alternatively, the electronic control unit 10 and its method described herein may be implemented by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits.

[0076] Alternatively, the electronic control device 10 and the method described herein may be implemented by one or more dedicated computers comprising a combination of a processor and memory programmed to perform one or more functions and a processor comprising one or more hardware logic circuits.

[0077] Furthermore, computer programs may be stored on a computer-readable, non-transitional tangible recording medium as instructions executed by a computer. In other words, the means and / or functions provided by a processor, etc., can be provided by software recorded in a physical memory device and the computer that executes it, by software alone, by hardware alone, or by a combination thereof. For example, some or all of the functions of a processor may be implemented as hardware. Embodiments of implementing a certain function as hardware include embodiments that use one or more ICs, etc.

[0078] This disclosure has been written in accordance with embodiments, but it is understood that this disclosure is not limited to such embodiments. This disclosure also includes various modifications and variations within the scope of equivalents. In addition, various combinations and forms, as well as other combinations and forms that include only one, more, or fewer of those elements, fall within the scope and idea of ​​this disclosure. [Explanation of Symbols]

[0079] In the diagram, 11 represents the microcontroller (anomaly detection unit), 11a represents the power supply voltage monitor, 13 represents the boost circuit, 19 represents multiple power supply lines, and 27 represents the control circuit.

Claims

1. A boost circuit (13) that increases the power supply voltage supplied from an external power supply (18) through multiple power supply lines (19), A power supply voltage monitor (11a) for detecting the power supply voltage supplied to the plurality of power supply lines, An abnormality determination unit (11) determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage detected by the power supply voltage monitor exceeds a predetermined abnormality determination threshold between a predetermined first state in which only the boost circuit is operated and a predetermined second state in which the boost circuit is not operated, which differs from the first state. An electronic control device equipped with the following features.

2. A boost circuit (13) that increases the power supply voltage supplied from an external power supply (18) through multiple power supply lines (19), A power supply voltage monitor (11a) for detecting the power supply voltage supplied to the plurality of power supply lines, An abnormality determination unit (11) determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage detected by the power supply voltage monitor exceeds a predetermined abnormality determination threshold between a first state in which the boost circuit is operated when the power is turned on and a second state in which it is operated during the shutdown process, which is different from the first state, during a single driving cycle. An electronic control device equipped with the following features.

3. The electronic control device according to claim 1 or 2, further comprising an abnormality detection mode in which, when the abnormality determination unit determines an abnormality in the power supply line, the control circuit uses an abnormality detection boost current value that is larger than the boost current value used during normal vehicle control to boost the boost circuit.

4. The electronic control device according to claim 1 or 2, wherein when the abnormality determination unit determines an abnormality in the power supply line, the control circuit has an abnormality detection mode that causes the boost circuit to increase the voltage using an abnormality detection voltage that is greater than the charge completion voltage of the boost circuit during normal vehicle control.

5. The electronic control device according to claim 1 or 2, wherein when the abnormality determination unit determines an abnormality in the power supply line, it pre-operates a circuit connected to the boost circuit to discharge the boosted voltage of the boost circuit before operating the boost circuit.

6. The electronic control device according to claim 1 or 2, wherein when the abnormality determination unit determines an abnormality in the power supply line, it operates the circuits connected to the plurality of power supply lines while the boost circuit is performing a boost operation.

7. The predetermined abnormality determination threshold indicates a predetermined abnormality determination threshold with respect to the moving average value of the power supply voltage drop, The electronic control device according to claim 1 or 2, wherein the abnormality determination unit determines that there is an abnormality in the power supply line when the moving average value of the amount of drop in the power supply voltage when the boost circuit is operated to boost the voltage exceeds the abnormality determination threshold.

8. The electronic control device according to claim 1 or 2, wherein the abnormality determination unit determines that there is an abnormality in the power supply line if the amount of change in the power supply voltage when the boost circuit is boosted each time it is started by the soak timer exceeds the predetermined abnormality determination threshold.

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