JP2009234437A - Vehicular control device, electric vehicle, and method for detecting trouble of vehicular control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular control device capable of reliably detecting a trouble of a switch and a method for detecting the trouble, and an electric vehicle having the vehicular control device. <P>SOLUTION: When a trouble determination signal is input from a signal generation circuit for detecting a trouble after shifted to a sleep mode (YES in a step S14), a CPU restarts the trouble determination signal as a starting signal (step S15), writes the result of determination indicating that a second switch is in trouble (step 16) in a memory as information on trouble occurrence (step S17), and furthermore transmits information on trouble occurrence from a radio communication means to a cellular phone possessed by a user such as a person in a vehicle wirelessly (step S18). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle control device that supplies power from a power supply source to a microcomputer that controls a system in the vehicle via the power supply line by turning on a switch provided in the power supply line, and a failure detection method therefor The present invention also relates to an electric vehicle including the vehicle control device.

  Conventionally, in an electronic control device (vehicle control device) mounted on a vehicle, a power supply relay (switch) is turned on due to at least one of a key switch and an ignition switch being turned on. Supply power. In addition, the vehicle control device is configured to supply power until the microcomputer completes a predetermined process (stop process for the system in the vehicle) and stops operating even when the key switch or the ignition switch is turned off. It has a power supply self-holding function that keeps the relay on and continues to supply power to the microcomputer (see Patent Document 1).

  In this case, in the vehicle control device, the power supply holding time from the start of the system stop process due to the key switch or the ignition switch being turned off to the stop of the operation of the microcomputer is set at regular intervals. The counter value in the flash ROM is counted up, and then, when the key switch or the ignition switch is turned on, if the counter value is smaller than the first determination value, it is determined that the power supply self-holding function is abnormal, On the other hand, if the counter value is larger than the second determination value, a failure detection process for the power supply relay is performed in which it is determined that the power cut-off function for stopping the power supply by turning off the power supply relay is abnormal.

JP 2006-347441 A

  The counter value used for the failure detection process described above corresponds to the power holding time from the start of the system stop process due to the key switch or ignition switch being turned off until the microcomputer stops operating. When the required time (stop processing time) changes, the counter value also changes according to the change in the stop processing time. As a result, when the stop processing time becomes long and the counter value becomes large, it is determined that the power shut-off function is normal but abnormal. That is, there is a possibility that a failure of the power supply relay (switch) is erroneously detected.

  The present invention has been made in consideration of such problems, and is capable of reliably detecting a switch failure, a failure detection method thereof, and an electric vehicle including the vehicle control device. The purpose is to provide.

The vehicle control device according to the present invention includes:
A power supply source, a microcomputer for controlling a system in the vehicle, a start signal generation circuit having a capacitor, the power supply source, the microcomputer, and the start signal generation circuit are connected via a switch and the switch A power supply line for supplying power from the power supply source to the microcomputer and the activation signal generation circuit through the switch, a discharge means for discharging the charge accumulated in the capacitor, and turning on the switch. And a shut-off means for controlling the switch to switch from to off,
The start signal generation circuit generates a start signal when the voltage of the capacitor becomes equal to or higher than a predetermined voltage, and outputs the start signal to the microcomputer. To stop the generation of the start signal when the charge accumulated in the capacitor is discharged,
The blocking means controls the switch to switch the switch from on to off when the generation of the activation signal is stopped;
The microcomputer stops the operation of the microcomputer after the stop process and the discharge of the electric charge by the discharging means are completed, and starts when the start signal is input in the stopped state. It is characterized in that it is determined that is malfunctioning.

Further, a failure detection method for a vehicle control device according to the present invention includes:
When power is supplied from the power supply source to the microcomputer and the start signal generation circuit via the power supply line by turning on the switch,
During the stop process for the system in the vehicle by the microcomputer, the discharge means discharges the charge accumulated in the capacitor of the start signal generation circuit to stop the start signal generation by the start signal generation circuit,
Controlling the switch so that the switch is switched from on to off by a shut-off means when the generation of the activation signal is stopped;
The microcomputer stops operating after completion of the stopping process and the discharging of the electric charge by the discharging means, and the voltage of the capacitor becomes a predetermined voltage or more in the stopped state, and the starting signal generating circuit starts the starting When a signal is generated and output to the microcomputer, the microcomputer is activated to determine that the switch has failed.

  According to these inventions, after the stop processing for the system in the microcomputer and the discharge of the electric charge accumulated in the capacitor by the discharging means are completed, the microcomputer stops the operation (sleep mode). If the start signal is input to the microcomputer in the stopped state after the transition to (1), the microcomputer restarts based on the start signal and determines that the switch is faulty.

  That is, when the switch has failed before the stop process and the discharge, power is supplied from the power supply source to the microcomputer and the start signal generation circuit via the switch. Even when the electric charge accumulated in the capacitor by the discharging means is discharged once during the stop process, the power supply causes the capacitor to be supplied to the capacitor during the time when the microcomputer is stopped (sleep mode). The charge is accumulated again. As a result, when the voltage of the capacitor becomes equal to or higher than the predetermined voltage due to the re-accumulation of the charge, the activation signal generation circuit generates the activation signal and outputs it to the microcomputer.

  Therefore, the microcomputer can reliably detect that the switch has failed by restarting based on the input of the start signal from the start signal generation circuit during the time period of the sleep mode. it can.

  The activation signal generation circuit further includes a resistor connected to the power supply line, and the power is supplied from the power supply line to the capacitor via the resistor, and the voltage of the capacitor is The activation signal is generated when the voltage exceeds the predetermined voltage.

  As a result, during the sleep mode time period, the voltage of the capacitor tends toward the predetermined voltage relatively slowly based on the time constant determined by the resistance value of the resistor and the capacitance of the capacitor. To rise. In other words, the provision of the resistor makes it possible to moderate the time change of the voltage (delay the rise of the voltage), so that the failure of the switch can be detected with higher accuracy. In addition, since the activation signal generation circuit that generates the activation signal can be configured easily and simply, the cost of the vehicle control device can be reduced.

  Furthermore, it is preferable that the microcomputer warns the outside of the switch failure when it is determined that the switch has failed.

  Thus, when the vehicle is stopped, a user such as a passenger of the vehicle is notified of the presence or absence of the failure of the switch, and the user is prompted to repair the vehicle equipped with the vehicle control device. It becomes possible. That is, since the switch failure detection process is performed by the vehicle control device, it is not necessary for the user to confirm the occurrence of the switch failure.

  Here, the vehicle control device further includes storage means for storing a determination result relating to the failure of the switch determined by the microcomputer, and the storage means is built in the microcomputer and the power It is preferable that the memory is supplied with power from a supply source, or is a non-volatile memory arranged outside the microcomputer.

  Thereby, even if the operation of the microcomputer is stopped due to the stop of the power supply, the determination result stored in the storage means is not erased. As a result, it is possible to read out the determination result from the storage means after the operation is stopped and determine whether or not the switch is out of order.

  In this case, the microcomputer refers to the determination result stored in the storage means at the next start-up, and determines that the determination result is a determination result indicating a failure of the switch. It is preferable to warn the outside of the failure.

  Accordingly, when the vehicle is started next time, the user can be notified of the failure of the switch, and the user can be prompted to repair the vehicle equipped with the vehicle control device. That is, since the failure detection process of the switch is performed by the vehicle control device, it is unnecessary to confirm the occurrence of the switch failure by the user, and if the switch is broken, the next start of the vehicle is performed. Occasionally, the occurrence of the failure is notified to the user, so that when the vehicle is stopped, the user can immediately leave the vehicle even during the stop process for the system of the vehicle. Become.

  Furthermore, it is preferable that the switch is a power supply self-holding switch that switches from off to on by an on command from the microcomputer, and switches from on to off by an off command from the microcomputer.

  The vehicle control device further includes a communication unit for communicating with an external communication device, and the microcomputer relates to the failure of the switch when the microcomputer determines that the switch is broken. The determination result is preferably transmitted to the communication device via the communication unit.

  As a result, if the user has the communication device, the determination result can be immediately notified to the user.

  Here, the electric vehicle according to the present invention includes the vehicle control device, the power supply source is a power storage device that supplies power to the electrical equipment mounted on the vehicle, and the system is configured to drive the vehicle. It is the vehicle drive system provided with the electric power source for operation.

  Accordingly, when another electronic circuit is connected to the switch, power is supplied from the power storage device to the other electronic circuit via the switch when the electric vehicle is stopped due to the failure of the switch. As a result, it is possible to reliably prevent the voltage of the power storage device from decreasing.

  In addition, the vehicle control device includes storage means for storing a determination result relating to the failure of the switch determined by the microcomputer, and start means for periodically starting the microcomputer when the electric vehicle is stopped. The microcomputer further determines whether the determination result stored in the storage means indicates a failure of the switch when the microcomputer is activated by the activation means, and indicates the failure. Preferably, the vehicle drive system is controlled so that the power storage device is charged from the vehicle drive power source when it is determined.

  Thereby, when the electric vehicle is stopped due to the failure of the switch, power is supplied from the power storage device to the microcomputer and the activation signal generation circuit via the switch, and the voltage of the power storage device is reduced. In addition, by charging the power storage device from the vehicle driving power source, it is possible to effectively suppress a voltage drop of the power storage device.

  In this case, the power source for driving the vehicle is a fuel cell, the vehicle driving system is a fuel cell system including the fuel cell, and the microcomputer is activated by the starting means when the fuel is started. It is preferable to control the fuel cell system so as to perform a scavenging process in the gas flow path of the battery.

  In the fuel cell system, the power in the system needs to be covered by its own power generation function, so that the amount of power that can be used when power generation is stopped (when the electric vehicle is stopped) is limited. Therefore, when the electric vehicle is stopped, the scavenging process can be performed efficiently by performing the scavenging process in accordance with the regular activation by the activation unit. Further, by sharing the starting means for starting the microcomputer for charging the power storage device from the vehicle driving power source and starting the microcomputer for performing the scavenging process, For this process, it is not necessary to separately provide a starting means. Further, by performing a failure detection process of the switch after the fuel cell system is stopped (sleep mode time period), the failure of the switch can be prevented regardless of the length of the start processing time and the stop processing time of the fuel cell system. It can be detected efficiently.

  Further, when the outside air temperature is lower than a predetermined temperature, the microcomputer may control the fuel cell system so as to perform a scavenging process in the gas flow path of the fuel cell during a stop process for the fuel cell system. preferable.

  When the power generation is stopped, the water generated by the power generation remains in the gas flow path, so that the remaining water freezes in an environment below freezing point and hinders the supply and discharge of the reaction gas (hydrogen, air). There is a risk that the starting performance of the fuel cell at a low temperature is lowered. Therefore, by performing the scavenging process during the stop process of the electric vehicle, the scavenging process can be performed efficiently and the starting performance of the fuel cell can be maintained even at a low temperature.

  Further, by performing the scavenging process at the time of the stop process, the time required for the system stop process by the microcomputer becomes longer. Even in this case, the fuel cell system is stopped after the stop (time period of the sleep mode). Since the switch failure detection process is performed, the switch failure can be detected efficiently regardless of the length of time required for the scavenging process and the system stop process.

  According to the present invention, after the stop processing for the system in the microcomputer and the discharge of the electric charge accumulated in the capacitor by the discharging means are completed, the microcomputer stops the operation (after entering the sleep mode). If there is an input of a start signal to the microcomputer in the stopped state, the microcomputer restarts based on the start signal and determines that the switch is faulty.

  That is, when the switch has failed before the stop process and the discharge, power is supplied from the power supply source to the microcomputer and the start signal generation circuit through the switch. Even if the charge accumulated in the capacitor by the discharge means during the stop process is discharged once, the charge is supplied to the capacitor by the power supply during a time period when the operation of the microcomputer is stopped (sleep mode). Is accumulated again. As a result, when the voltage of the capacitor becomes equal to or higher than a predetermined voltage due to the re-accumulation of the charge, the activation signal generation circuit generates the activation signal and outputs it to the microcomputer.

  Therefore, the microcomputer can reliably detect that the switch has failed by restarting based on the input of the start signal from the start signal generation circuit during the time period of the sleep mode. it can.

  FIG. 1 is a circuit diagram of a vehicle control apparatus 10 according to this embodiment.

  The vehicle control device 10 controls a system in the vehicle {for example, a fuel cell system (vehicle drive system) 52 of a fuel cell vehicle (electric vehicle) 50 shown in FIG. And a battery (power supply source, power storage device) 16 connected to the terminals 14a and 14d of the control unit 12, and a first switch 18 for connecting the positive electrode of the battery 16 and the terminal 14b of the control unit 12. Note that the terminal 14c of the control unit 12 and the negative electrode of the battery 16 are each grounded.

  The first switch 18 is a key switch or an ignition switch of the vehicle, and is turned on or off due to an operation of a passenger of the vehicle. The battery 16 is a 12V battery mounted on the vehicle, for example.

  In the control unit 12, a CPU (microcomputer) 20, a diode 22, a second switch 24, a failure detection signal generation circuit (startup signal generation circuit) 26, a capacitor 28, and an OR circuit 30 are arranged. Has been.

  The CPU 20 is connected to the positive electrode of the battery 16 via the first switch 18 and the terminal 14b, is connected to the positive electrode of the battery 16 via the terminal 14d and the diode 22, and is further connected to the battery via the terminal 14a and the second switch 24. 16 positive electrodes are connected.

  The OR circuit (blocking means) 30 has one input terminal connected to the terminal 14 b and the CPU 20, the other input terminal connected to the CPU 20, and an output terminal connected to the second switch 24. In this case, when a DC voltage is applied from the battery 16 to the OR circuit 30 and the CPU 20 via the first switch 18 and the terminal 14b by turning on the first switch 18, the OR circuit 30 uses the DC voltage as a self-holding request signal. (ON command) Output to the second switch 24 as S2. The OR circuit 30 also outputs a self-holding command signal S3 from the CPU 20 to the second switch 24 as a self-holding request signal S2.

  The second switch 24 switches from OFF to ON due to the input of the self-holding request signal S2 from the OR circuit 30, while it switches from ON to OFF due to the stop (OFF command) of the self-holding request signal S2. A power supply self-holding switch (a power supply relay as a power supply self-holding circuit) that switches. In this case, when the second switch 24 is turned on, the battery 16 is connected to the CPU 20 and the failure detection signal generation circuit 26 via the terminal 14a and the second switch 24, and the power input terminal Vcc of the CPU 20 and the failure detection signal generation are generated. A DC voltage is applied to the input side (resistor 32 side) of the circuit 26. That is, the DC voltage is an input voltage for supplying power from the battery 16 to the CPU 20 and the failure detection signal generation circuit 26. Accordingly, a line including the terminal 14a and the second switch 24 from the positive electrode side of the battery 16 to the CPU 20 is a power supply line (main power line) 21 for the CPU 20, and in FIG. It is indicated by.

  The CPU 20 receives a DC voltage from the battery 16 via the first switch 18 and the terminal 14b when the first switch 18 is turned on (the activation signal S1 is supplied), and the terminal from the battery 16 when the second switch 24 is turned on. It starts when a DC voltage is applied to the power input terminal Vcc via 14a and the second switch 24. Further, the CPU 20 outputs a self-holding command signal S3 to the OR circuit 30 at the time of activation. Further, when the DC voltage is no longer applied due to the first switch 18 being turned off, the CPU 20 regards the start signal S1 (DC voltage) that has become substantially 0 level as the system stop request signal S5 and executes the system stop process for the system. Then, the operation is stopped {transition to the low power consumption mode (sleep mode)}. In this case, since the supply of the activation signal S1 to one input terminal of the OR circuit 30 is stopped, the output of the self-holding command signal S3 from the CPU 20 to the OR circuit 30 is stopped, so that the OR circuit 30 transfers to the second switch 24. The output of the self-holding request signal S2 is also stopped, and the second switch 24 is switched from on to off. As a result, power supply from the battery 16 to the CPU 20 is stopped.

  When the second switch 24 is turned on, power is supplied not only to the CPU 20 and the failure detection signal generation circuit 26 but also to other electronic circuits in the control unit 12. The capacitor 28 is connected in parallel to the battery 16, the CPU 20, and the failure detection signal generation circuit 26 between the second switch 24, the CPU 20, and the failure detection signal generation circuit 26.

  The failure detection signal generation circuit 26 includes a resistor 32 connected to the second switch 24 and the power input terminal Vcc of the CPU 20, a capacitor 34 connected to the resistor 32, a capacitor 34 side of the resistor 32, and a second one. A diode 36 connected between the switch 24 and a Schmitt trigger gate 38 connected between the capacitor 34 and the diode 36 and the CPU 20.

  In this case, when power is supplied from the battery 16 to the failure detection signal generation circuit 26 via the second switch 24 when the second switch 24 is turned on, the voltage of the capacitor 34 is changed to the resistor 32 as time passes. Gradually increases based on the time constant determined by the resistance value and the capacitance of the capacitor 34. Since the voltage of the capacitor 34 is an input voltage of the Schmitt trigger gate 38, when the voltage value of the input voltage becomes equal to or higher than the upper threshold (predetermined voltage) Vth (see FIG. 3) of the Schmitt trigger gate 38, the Schmitt trigger gate 38 is The failure determination signal S4 is generated and output to the CPU 20. The Schmitt trigger gate 38 malfunctions when the voltage value becomes lower than the lower threshold (the voltage of the capacitor 34 at approximately 0 level) due to the OFF of the second switch 24 or the discharge of the charge accumulated in the capacitor 34 described later. The generation of the determination signal S4 is stopped.

  During the system stop process, the CPU 20 outputs a discharge command signal S8 to the transistor (discharge means) 48 connected in parallel with the capacitor 34 to turn on the transistor 48, and the closed circuit constituted by the capacitor 34 and the transistor 48 is turned on. The electric charge accumulated in the capacitor 34 is discharged by the circuit. As a result, when the voltage value of the capacitor 34 becomes equal to or lower than the lower limit threshold, the Schmitt trigger gate 38 stops generating the failure determination signal S4.

  By the way, when the output of the discharge command signal S8 from the CPU 20 to the transistor 48 is stopped due to the transition of the CPU 20 to the sleep mode, the transistor 48 is switched from on to off, and the failure detection signal generation circuit is switched from the power supply line 21. By supplying power to the capacitor 26, charges are accumulated again in the capacitor 34, and the voltage of the capacitor 34 starts to rise again (see FIG. 3). In this case, the vehicle control device 10 turns off the second switch 24 before the voltage value of the capacitor 34 reaches the upper limit threshold value Vth, and stops the power supply to the failure detection signal generation circuit 26. The generation of the failure determination signal S4 in the sleep mode time zone is stopped.

  When the CPU 20 shifts to the sleep mode and is in the stop state, if there is an input of the failure determination signal S4 from the failure detection signal generation circuit 26, the CPU 20 restarts using the failure determination signal S4 as the start signal, and the second It is determined that a failure has occurred in the switch 24 (a failure that does not switch from on to off even when an off command is issued, and the second switch 24 is welded and turned on). As a failure occurrence information, it is stored in the memory 40 built in the CPU 20, and a notification signal S9 indicating the failure occurrence information is transmitted wirelessly from the antenna 47 of the wireless communication means 45 via the terminal 14f. Is transmitted to a mobile phone (communication device) 49 possessed by.

  Since the memory 40 is always supplied with power from the battery 16 via the terminal 14d, even if the power supply from the battery 16 to the CPU 20 is stopped when the second switch 24 is switched from ON to OFF by the OFF command, The failure occurrence information stored in the memory 40 is not erased.

  The vehicle control device 10 according to this embodiment is configured as described above. Next, a failure detection process (failure detection method) of the vehicle control device 10 performed when the vehicle is stopped will be described with reference to FIG. This will be described with reference to the flowchart of FIG. 3 and the time charts of FIGS. FIG. 3 shows a case where the second switch 24 performs a normal operation (operation that switches from on to off due to an off command), while FIG. 4 shows that the second switch 24 operates abnormally ( This shows the case of performing an operation when the switch is not switched from ON to OFF even when an OFF command is issued. 2 is a failure detection process applicable to both the normal operation and the abnormal operation.

  First, the case where the second switch 24 performs a normal operation will be described with reference to FIGS.

  At time t1, when the first switch 18 is turned off due to the operation of the vehicle occupant (step S10), the application of the DC voltage from the battery 16 to the OR circuit 30 and the CPU 20 (supply of the start signal S1) is stopped. To do. The CPU 20 regards the start signal S1 that has become substantially 0 level as the system stop request signal S5, and executes the system stop process for the system (step S11). At time t2 during the system stop process, the CPU 48 performs a discharge command signal. S8 is output. Thereby, the transistor 48 is turned on, and the electric charge accumulated in the capacitor 34 is discharged by the closed circuit of the transistor 48 and the capacitor 34 (step S12). As a result, the voltage of the capacitor 34 is caused by the capacitance of the capacitor 34. According to the determined time constant, it gradually decreases with time.

  At time t3, the voltage value of the capacitor 34 becomes equal to or lower than the lower threshold of the Schmitt trigger gate 38, the output of the failure determination signal S4 from the Schmitt trigger gate 38 to the CPU 20 is stopped, and the CPU 20 performs the system stop process. Completion and operation stop (transition to sleep mode) (step S13). As a result, the output of the discharge command signal S8 to the transistor 48 is stopped, the transistor 48 is turned from on to off, and electric power is supplied to the capacitor 34 from the power supply line 21 to the failure detection signal generation circuit 26. Accumulated again, the voltage on the capacitor 34 rises again.

  However, the supply of the activation signal S1 to one input terminal of the OR circuit 30 is stopped and the output of the self-holding command signal S3 from the CPU 20 in the stopped state to the OR circuit 30 is also stopped. The output of the self-holding request signal S2 to 24 is stopped, and at time t4, the second switch 24 is switched from on to off. As a result, the power supply from the battery 16 to the CPU 20 and the failure detection signal generation circuit 26 is stopped, and the electric charge accumulated in the capacitor 34 is discharged again. Therefore, the voltage value of the capacitor 34 is set to the upper threshold value Vth. Gradually falls to level 0 without reaching. Therefore, when the second switch 24 is normal, the failure determination signal S4 is not input to the CPU 20 in the sleep mode time zone (NO in step S14).

  Time t5 indicates the time when the voltage value of the capacitor 34 reaches the upper limit threshold Vth when the second switch 24 is not turned off. Further, the input voltage (DC voltage) supplied to the power input terminal Vcc of the CPU 20 gradually decreases with time from the time t4, but this is a time constant determined by the capacitance of the capacitor 28. Due to the gradual decline according to.

  When the vehicle is started, the following processing is performed and the operation of the CPU 20 is started.

  First, when the first switch 18 is turned on due to the operation of the vehicle occupant, a DC voltage is applied from the battery 16 to the OR circuit 30 and the CPU 20 (the activation signal S1 is supplied), and the OR circuit 30 is activated. The signal S1 is output to the second switch 24 as a self-holding request signal S2. As a result, the second switch 24 is switched from OFF to ON due to the input of the self-holding request signal S2, whereby the CPU 20 and the failure detection signal generation circuit are connected from the battery 16 via the terminal 14a and the second switch 24. Power is supplied to the CPU 26, and the CPU 20 starts the startup process due to the input of the startup signal S1 and the power supply. Further, the CPU 20 outputs a self-holding command signal S3 to the OR circuit 30 during the startup process. Further, the failure detection signal generation circuit 26 outputs a failure determination signal S4 from the Schmitt trigger gate 38 to the CPU 20 when the voltage of the capacitor 34 reaches the upper limit threshold Vth due to the power supply.

  Next, the case where the second switch 24 performs an abnormal operation will be described with reference to FIGS. Even if the output of the self-holding request signal S2 is stopped (even if there is an off command), the abnormal operation continues to hold the second switch 24 on without being switched from on to off (power supply self-holding state). To continue to maintain). In this case, the CPU 20 performs the same processing as in the normal operation (see FIG. 3) until immediately before the sleep mode in step S13 (before time t3 in FIG. 4), so here, after step S13 and at time t3 The subsequent processing will be described.

  When the CPU 20 shifts to the sleep mode (step S13), if the second switch is out of order, power is continuously supplied from the battery 16 to the failure detection signal generation circuit 26 via the power supply line 21. Therefore, even during the sleep mode time period, electric charges are accumulated in the capacitor 34 due to the power supply, and as a result, the voltage value of the capacitor 34 gradually increases toward the upper limit threshold Vth. When the voltage value reaches the upper threshold value Vth at time t5, the Schmitt trigger gate 38 generates a failure determination signal S4 and outputs the failure determination signal S4 to the CPU 20, and the CPU 20 restarts with the input failure determination signal S4 as a start signal. (YES in step S14, step S15). As a result, the CPU 20 determines that the second switch 24 has failed due to the input of the failure determination signal S4 at time t6 after the activation process (step S16), and that the second switch 24 has failed. Is written in the memory 40 as failure occurrence information (step S17).

  Further, after writing the failure occurrence information in the memory 40, the CPU 20 sends a notification signal S9 indicating a failure of the second switch 24 wirelessly via the terminal 14f and the antenna 47 of the wireless communication means 45 such as a vehicle passenger. The data is transmitted to the mobile phone 49 possessed by the user (step S18). Then, after the above-described failure determination process is completed, the CPU 20 performs an operation stop process, and again shifts to the sleep mode at time t7 (step S19).

  In the time period from time t6 to time t7, the CPU 20 outputs a self-holding command signal S3 to the OR circuit 30, and the OR circuit 30 uses the self-holding command signal S3 as a self-holding request signal S2 for the second time. Output to the switch 24.

  As described above, according to the above-described embodiment, after the system stop process in the CPU 20 and the discharge of the charge accumulated in the capacitor 34 when the transistor 48 is turned on are completed, the CPU 20 stops operating ( If the failure determination signal S4 is input to the CPU 20 in the stopped state after the transition to the sleep mode), the CPU 20 restarts with the failure determination signal S4 as the activation signal, and the second switch 24 fails (second switch 24). Even if there is an off command due to welding, it is determined that the failure does not switch from on to off.

  That is, when the second switch 24 has failed before the system stop process and the discharge, power is supplied from the battery 16 to the CPU 20 and the failure detection signal generation circuit 26 via the second switch 24. Therefore, even if the charge accumulated in the capacitor 34 is once discharged by turning on the transistor 48 during the system stop processing, the charge is supplied to the capacitor 34 by the power supply in the time mode of the sleep mode of the CPU 20. Is accumulated again. As a result, when the voltage value of the capacitor 34 becomes equal to or higher than the upper limit threshold Vth due to the re-accumulation of the charge, the failure detection signal generation circuit 26 generates a failure determination signal S4 and outputs it to the CPU 20. .

  Accordingly, the CPU 20 restarts based on the input of the failure determination signal S4 from the failure detection signal generation circuit 26 during the sleep mode time period, thereby reliably detecting that the second switch 24 is failed. be able to.

  By the way, in the technique described in Patent Document 1, the counter value in the flash ROM is counted up every certain time within the power holding time from the start of the system stop process to the stop of the operation of the microcomputer, and then the key switch or When the ignition switch is turned on, it is determined whether or not the power self-holding function and the power shut-off function are abnormal based on the counter value, so that the microcomputer is restarted after entering the sleep mode. It is impossible to detect a failure of the power supply relay in the sleep mode time zone.

  On the other hand, in this embodiment, as described above, if the failure determination signal S4 is input to the CPU 20, it is determined that the CPU 20 in the stopped state is activated and the second switch 24 has failed. The failure of the second switch 24 in the sleep mode time zone can also be reliably detected.

  The failure detection signal generation circuit 26 includes a resistor 32, a capacitor 34, and a Schmitt trigger gate 38. Power is supplied to the capacitor 34 via the resistor 32, and the voltage value of the capacitor 34 has an upper threshold value. Since the failure determination signal S4 is generated when Vth becomes equal to or higher than Vth, the voltage value of the capacitor 34 is relatively gentle based on the time constant determined by the resistance value of the resistor 32 and the capacitance of the capacitor 34. It rises toward the upper threshold value Vth. That is, by providing the resistor 32, the time change of the voltage value can be moderated (the increase of the voltage value is delayed), so that the failure of the second switch 24 can be detected with higher accuracy. It becomes. In addition, since the failure detection signal generation circuit 26 that generates the failure determination signal S4 can be easily and simply configured, the cost of the vehicle control device 10 can be reduced.

  In addition, when it is determined that the second switch 24 is malfunctioning, the user is alerted (notified) to the user such as a vehicle occupant by sound or screen display of the malfunction of the second switch 24. It is also possible to prompt repair of the vehicle on which the vehicle control device 10 is mounted. That is, if power is continuously supplied from the battery 16 to the control unit 12 due to the failure of the second switch 24, the output voltage (DC voltage) of the battery 16 may decrease and the battery may run out. By giving the warning to the user, it is possible to reliably prevent the battery from being generated and the battery 16 from being deteriorated due to the battery being discharged. That is, since the vehicle control device 10 performs the failure detection process of the second switch 24, it is not necessary for the user to confirm the occurrence of the failure of the second switch 24.

  Further, since the failure occurrence information is stored in the memory 40, the failure occurrence information stored in the memory 40 is not erased even if the operation of the CPU 20 is stopped due to the stop of the power supply. As a result, the failure occurrence information can be read from the memory 40 after the operation is stopped, and it can be determined whether or not the second switch 24 is broken.

  Therefore, when the CPU 20 determines that the information stored in the memory 40 is the failure occurrence information at the next start-up, the failure of the second switch 24 is notified to the user such as a vehicle passenger by sound or screen display. By giving warning (notification), it is possible to prompt the user to repair the vehicle on which the vehicle control device 10 is mounted. That is, since the failure detection processing of the second switch 24 is performed by the vehicle control device 10, it is unnecessary to confirm the occurrence of the failure of the second switch 24 by the user, and if the second switch 24 is broken, Since the occurrence of the failure is notified to the user at the next start of the vehicle, the user can immediately leave the vehicle even during the system stop process when the vehicle is stopped. It becomes.

  Specifically, when the CPU 20 determines that the second switch 24 has failed, the user possesses a notification signal S9 indicating failure determination information via the terminal 14f, the wireless communication unit 45, and the antenna 47. By transmitting it to the mobile phone 49, it is possible to promptly notify the user of the failure determination information and prompt the repair of the vehicle.

  The vehicle control device 10 according to this embodiment is not limited to the above description, and can be changed to various configurations.

  That is, as shown in FIG. 5, a nonvolatile memory 42 may be arranged outside the CPU 20 instead of the memory 40 (see FIG. 1).

  Thereby, when failure occurrence information is stored in the memory 42, even if the operation of the CPU 20 is stopped due to the stop of the power supply to the CPU 20, the failure occurrence information stored in the memory 42 is not erased. Accordingly, even in this case, the same effect as the memory 40 described above can be obtained.

  6 and 7 show a case where the vehicle control device 10 is applied to control the fuel cell system 52 in the fuel cell vehicle 50. FIG.

  In the control unit 12, power is always supplied from the battery 16 via the terminal 14 e, and when the fuel cell vehicle 50 is stopped, the start signal S 6 is output to the CPU 20 periodically (intermittently) and the OR circuit 30. The periodic activation means 44 for outputting the self-holding request signal S7 is arranged. Therefore, by providing the control unit 12 with the periodic activation means 44 having the above-described alarm clock function, the second switch 24 can perform self-holding according to the self-holding request signal S7 even when the fuel cell vehicle 50 is stopped. Switching from OFF to ON due to the input of the request signal S2, and as a result, it is possible to supply power from the battery 16 to the power input terminal Vcc of the CPU 20 via the terminal 14a and the second switch 24.

  The fuel cell vehicle 50 has a current (electric power) from the fuel cell system 52 in addition to the fuel cell system 52 as a hybrid power supply system including the fuel cell 54, the temperature sensor 62, the air compressor 60 and the battery 66. It further includes a traveling motor 58 supplied through the inverter 56, a downverter 68 that steps down the voltages of the fuel cell 54 and the battery 66, and an auxiliary machine (electric equipment) 64 that receives power supply from the battery 16. In this case, the voltage stepped down by the downverter 68 is supplied to the battery 16 and stored, or is supplied to the auxiliary machine 64.

  The fuel cell 54 has, for example, a stack structure in which cells formed by sandwiching a solid polymer electrolyte membrane between an anode electrode and a cathode electrode from both sides are stacked, and hydrogen (fuel gas) as a reaction gas and air (oxidant) The generated current generated by the electrochemical reaction of gas) is supplied to the inverter 56 and / or the battery 66 side. The temperature sensor 62 measures the temperature of the fuel cell 54 and outputs the measured temperature (measured value) to the control unit 12.

  The CPU 20 periodically inputs the measurement input from the temperature sensor 62 when the fuel cell vehicle 50 is stopped (when the power generation of the fuel cell 54 is stopped) while the fuel cell vehicle 50 is started by the start signal S6 and is receiving power supply. When the measured value is compared with the predetermined threshold temperature and it is determined that the measured value is lower than the threshold temperature, the air compressor 60 is driven to stop the anode in the fuel cell 54 when power generation is stopped. In addition, a scavenging process is performed on the cathode and the flow path of the reaction gas.

  That is, even when the power generation of the fuel cell 54 is stopped, the water generated by the power generation remains in the gas flow path of the fuel cell 54. Therefore, in the environment below freezing point, the remaining water freezes. As a result, supply and discharge of the reaction gas (hydrogen, air) may be hindered, and the starting performance of the fuel cell 54 at low temperatures may be deteriorated. .

  Therefore, in this embodiment, the temperature of the fuel cell 54 is measured by the temperature sensor 62 in a state in which the CPU 20 is periodically (intermittently) activated by the periodic activation unit 44 and the second switch 24 is turned on. When the measured temperature is lower than the threshold temperature, the air compressor 60 is driven to perform a scavenging process on the fuel cell 54 that is not generating power. That is, in the fuel cell system 52, since the power in the fuel cell system 52 needs to be covered by its own power generation function, the amount of power that can be used when power generation is stopped (when the fuel cell vehicle 50 is stopped) is limited. is there. Therefore, when the fuel cell vehicle 50 is stopped, the scavenging process can be efficiently performed by performing the scavenging process in accordance with the periodic activation by the periodic activation means 44, and the fuel cell 54 can be operated at low temperatures. The starting performance can be maintained.

  The scavenging process performed in the fuel cell 54 is known (see, for example, Japanese Patent Application Laid-Open No. 2005-302515), and thus detailed description thereof is omitted in this specification.

  6 and 7, when the CPU 20 determines that the outside air temperature is lower than the threshold temperature during the system stop process for the fuel cell system 52, the CPU 20 drives the air compressor 60 and the anode in the fuel cell 54. In addition, a scavenging process may be performed on the cathode and the flow path of the reaction gas.

  That is, as described above, in the fuel cell system 52, the power in the fuel cell system 52 needs to be covered by its own power generation function, and the amount of power that can be used when power generation is stopped (when the fuel cell vehicle 50 is stopped). Therefore, by performing the scavenging process during the operation of the fuel cell vehicle 50, the scavenging process can be performed efficiently and the starting performance of the fuel cell 54 can be maintained even at low temperatures. It becomes possible.

  Further, by performing the above-described scavenging process at the time of the system stop process, the time required for the system stop process in the CPU 20 becomes longer, but since the failure detection process of the second switch 24 is performed during the sleep mode time zone, The failure of the second switch 24 can be detected efficiently regardless of the length of time required for the scavenging process and the system stop process.

  Note that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the contents described in this specification.

It is a circuit diagram of a control device for vehicles concerning one embodiment of this invention. It is a flowchart which shows the failure detection process of the control apparatus for vehicles. It is a time chart at the time of normal operation of the 2nd switch. It is a time chart at the time of abnormal operation of the 2nd switch. It is a circuit diagram of the control apparatus for vehicles provided with the non-volatile memory. It is a circuit diagram of the control apparatus for vehicles provided with the periodical starting means. FIG. 7 is a block diagram of a fuel cell vehicle to which the vehicle control device of FIG. 6 is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Vehicle control apparatus 12 ... Control unit 14a-14f ... Terminal 16, 66 ... Battery 18 ... 1st switch 20 ... CPU
DESCRIPTION OF SYMBOLS 21 ... Power supply line 22, 36 ... Diode 24 ... 2nd switch 26 ... Fault detection signal generation circuit 28 ... Capacitor 30 ... OR circuit 32 ... Resistor 34 ... Capacitor 38 ... Schmitt trigger gate 40, 42 ... Memory 44 ... Periodic Starting means 45 ... Wireless communication means 47 ... Antenna 48 ... Transistor 49 ... Mobile phone 50 ... Fuel cell vehicle 52 ... Fuel cell system 54 ... Fuel cell 56 ... Inverter 58 ... Motor 60 ... Air compressor 62 ... Temperature sensor 64 ... Auxiliary machine 68 ... Downverter

Claims (14)

A power supply,
A microcomputer for controlling the system in the vehicle;
A start signal generation circuit having a capacitor;
The power supply source is connected to the microcomputer and the activation signal generation circuit via a switch, and power is supplied from the power supply source to the microcomputer and the activation signal generation circuit via the switch when the switch is turned on. Power supply line to perform,
Discharging means for discharging the charge accumulated in the capacitor;
Shut-off means for controlling the switch to switch the switch from on to off;
With
The start signal generation circuit generates a start signal when the voltage of the capacitor becomes equal to or higher than a predetermined voltage, and outputs the start signal to the microcomputer. On the other hand, the discharge means is used during a stop process for the system in the microcomputer. To stop the generation of the start signal when the charge accumulated in the capacitor is discharged,
The blocking means controls the switch to switch the switch from on to off when the generation of the activation signal is stopped;
The microcomputer stops the operation of the microcomputer after the stop process and the discharge of the electric charge by the discharging means are completed, and starts when the start signal is input in the stopped state. It is determined that the vehicle is out of order. The vehicle control device according to claim 1,
The activation signal generation circuit further includes a resistor connected to the power supply line, and the power is supplied from the power supply line to the capacitor via the resistor, and a voltage of the capacitor is set to the predetermined voltage The vehicle control device, wherein the start signal is generated when the voltage exceeds a voltage. The vehicle control device according to claim 1 or 2,
When the microcomputer determines that the switch has failed, the microcomputer warns the outside of the switch failure. The vehicle control device according to any one of claims 1 to 3,
The vehicle control device further comprising storage means for storing a determination result relating to the failure of the switch determined by the microcomputer. The vehicle control device according to claim 4,
The vehicle control device, wherein the storage means is a memory built in the microcomputer and supplied with power from the power supply source. The vehicle control device according to claim 4,
The vehicle control device, wherein the storage means is a non-volatile memory arranged outside the microcomputer. The vehicle control device according to any one of claims 4 to 6,
The microcomputer refers to the determination result stored in the storage means at the next start-up, and determines that the failure of the switch is external when the determination result is a determination result indicating the failure of the switch. A vehicle control device characterized by warning the vehicle. The vehicle control device according to any one of claims 1 to 7,
The switch is a power supply self-holding switch that switches from off to on by an on command from the microcomputer, and switches from on to off by an off command from the microcomputer through the shut-off means. Vehicle control device. The vehicle control device according to any one of claims 1 to 8,
It further has a communication means for communicating with an external communication device,
When the microcomputer determines that the switch has failed, the microcomputer transmits a determination result relating to the switch failure to the communication device via the communication unit. A vehicle control device according to any one of claims 1 to 9, comprising:
The power supply source is a power storage device that supplies power to electrical equipment mounted on the vehicle,
The electric system according to claim 1, wherein the system is a vehicle drive system including a vehicle drive power source. The electric vehicle according to claim 10, wherein
The vehicle control device further includes storage means for storing a determination result relating to the failure of the switch determined by the microcomputer, and start means for periodically starting the microcomputer when the electric vehicle is stopped. And
When the microcomputer is activated by the activation unit, the microcomputer determines whether or not the determination result stored in the storage unit indicates a failure of the switch, and determines that it indicates the failure. Sometimes, the electric vehicle is controlled so as to charge the power storage device from the electric power source for driving the vehicle. The electric vehicle according to claim 11, wherein
The vehicle driving power source is a fuel cell,
The vehicle drive system is a fuel cell system including the fuel cell,
The electric vehicle, wherein the microcomputer controls the fuel cell system to perform a scavenging process in a gas flow path of the fuel cell when the microcomputer is activated by the activation means. The electric vehicle according to claim 12, wherein
When the outside air temperature is lower than a predetermined temperature, the microcomputer controls the fuel cell system so as to perform a scavenging process in the gas flow path of the fuel cell during a stop process for the fuel cell system. Electric vehicle to do. When power is supplied from the power supply source to the microcomputer and the start signal generation circuit via the power supply line by turning on the switch,
During the stop process for the system in the vehicle by the microcomputer, the discharge means discharges the charge accumulated in the capacitor of the start signal generation circuit to stop the start signal generation by the start signal generation circuit,
Controlling the switch so that the switch is switched from on to off by a shut-off means when the generation of the activation signal is stopped;
The microcomputer stops operating after completion of the stopping process and the discharging of the electric charge by the discharging means, and the voltage of the capacitor becomes a predetermined voltage or more in the stopped state, and the starting signal generating circuit starts the starting A failure detection method for a vehicle control device, wherein when the signal is generated and output to the microcomputer, the microcomputer is activated to determine that the switch is broken.

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