Vehicle control device

Abstract

To prevent a backup power source from exceeding capacity thereof when performing cranking to restart an engine under idle-stop control.SOLUTION: An IDSECU 6 maintains an amount of current necessary for cranking to restart an engine under IDS control based on a monitoring result of a usage amount of current by a CPU 3b so as to prevent a backup power of a body ECU 2 from exceeding capacity. Concurrently, the CPU 3b executes automatic inhibition control for an output state of a power amplifier 3c which is on-vehicle equipment related to amusement so as to prevent the backup power of the body ECU 2 from exceeding capacity.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle control device that controls a vehicle equipped with an idling stop control means that stops an engine when a predetermined engine stop condition is met and restarts the engine when a predetermined engine restart condition is met. [Background technology]

[0002] A vehicle equipped with an idling stop control function starts the engine by turning on the ignition (IG) switch, and then executes idling stop control until the engine is stopped by turning off the IG switch. When the outside temperature, battery charge state, vehicle speed, etc. are in a state in which the engine can be stopped, the engine is automatically stopped when specified engine stop conditions are met, and the engine is automatically restarted when specified engine restart conditions are met. This process is repeated.

[0003] For this type of vehicle, as described in Patent Document 1, for example, an idling stop determination unit determines the start of an idling stop, and when the set volume of the electronic volume is equal to or greater than a predetermined control target value, the electronic volume is controlled to lower the set volume to below the control target value, and when the end of the idling stop is determined, the set volume of the electronic volume is controlled to return to the value before control. In this way, audio output is lowered to an appropriate level during idling stop, and distortion, noise, sound cuts, etc. in the audio output that are unpleasant to the user are suppressed even if a drop in power supply voltage occurs when the engine is restarted after the idling stop. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-244182 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, in a vehicle equipped with an idling stop control function, when restarting the engine after idling stop, it is necessary to secure a drive current for the starter motor for cranking. Therefore, normally, the backup voltage from the backup power supply is added to the battery voltage and the boosted voltage is supplied to the starter motor and other electronic devices. However, the backup power supply has a capacity limit, and if a situation arises in which an amount of current used exceeds this capacity, the output of the backup power supply is stopped to protect the backup power supply.

[0006] However, in the case of the control device that controls the electronic volume described above, if the set volume of the electronic volume is so loud, so-called a roar, when idling stop begins, it may take time to lower the set volume of the electronic volume below the control target value, and the set volume may not drop completely below the control target value when cranking to restart the engine, resulting in a situation where an amount of current used exceeds the capacity of the backup power supply. If this occurs, the output of the backup power supply will stop, and the stop of the output of the backup power supply may cause problems in the operation of electronic devices (vehicle loads) powered by the backup power supply.

[0007] An object of the present invention is to prevent the capacity of a backup power supply from being exceeded during cranking to restart the engine under idling stop control. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the vehicle control device of the present invention is a vehicle control device that controls a vehicle equipped with an idling stop control means that stops the engine when a predetermined engine stop condition is met and restarts the engine when a predetermined engine restart condition is met, and is characterized by comprising a monitoring unit that monitors the amount of current used by a battery mounted on the vehicle and a plurality of on-board loads that are supplied with power from a backup power source having a predetermined capacity, storing electricity boosted to a voltage higher than the voltage of the battery and suppressing voltage drop during cranking to restart the engine, and a suppression unit that, when the predetermined engine stop condition is met, suppresses the output state of an on-board load related to entertainment for the vehicle among the plurality of on-board loads based on the monitoring result of the amount of current used by the monitoring unit so as not to exceed the capacity of the backup power source.

[0009] With this configuration, when a specified engine stop condition is met, the suppression unit automatically controls the output state of the in-vehicle load related to vehicle entertainment among the multiple in-vehicle loads based on the monitoring results of the amount of current used by the monitoring unit so as not to exceed the capacity of the backup power source.As a result, the amount of cranking current required for cranking during idling stop control can be secured within a range that does not exceed the capacity of the backup power source, and the engine can be restarted smoothly during idling stop control without causing the backup power source to be stopped.

[0010] Furthermore, based on the monitoring results of the amount of current used by the monitoring unit, the control unit forcibly suppresses the output state of the vehicle loads related to vehicle entertainment among the multiple vehicle loads before the engine is actually stopped by the idling stop control, so that even if the engine is restarted in the shortest time possible after being stopped by the idling stop control, the output state of the vehicle loads related to vehicle entertainment can be reliably suppressed and the amount of cranking current required for cranking can be secured.

[0011] In addition, the suppression unit may be configured to transmit an engine restart permission signal to the idling stop control means when the cranking current amount can be secured when restarting the engine by suppressing the output state of the on-board load related to the vehicle's entertainment, and to transmit an engine restart prohibition signal to the idling stop control means when the cranking current amount cannot be secured when restarting the engine by suppressing the output state of the on-board load related to the vehicle's entertainment.

[0012] In this way, when the amount of cranking current for engine restart in the idling stop control can be secured by suppressing the output state of the vehicle load related to vehicle entertainment among the multiple vehicle loads, the control unit transmits an engine restart permission signal to the idling stop control means, so that the engine can be restarted smoothly. On the other hand, when the amount of cranking current for engine restart cannot be secured even by suppressing the output state of the vehicle load related to vehicle entertainment among the multiple vehicle loads, the suppression unit transmits an engine restart prohibition signal to the idling stop control means, so that the engine restart in the idling stop control is not performed until the amount of cranking current for engine restart can be secured, and it is possible to prevent the power supply from the backup power source from being stopped.

[0013] In addition, when suppressing the output state of the in-vehicle load related to the vehicle's entertainment, the suppression unit may perform a guard process to prevent the output of the in-vehicle load related to the entertainment from increasing beyond a predetermined state due to user operation.

[0014] In this way, when the output state of an in-vehicle load related to vehicle entertainment among multiple in-vehicle loads is suppressed, a guard process is performed to prevent the output of the in-vehicle load related to entertainment from increasing above a predetermined state due to user operation, thereby preventing the power supply from the backup power source from being stopped while allowing the user to change the output state of the in-vehicle load related to entertainment to suit their preferences. Effect of the Invention

[0015] According to the present invention, by ensuring that the capacity of the backup power supply is not exceeded during cranking to restart the engine under idle stop control, it is possible to ensure the amount of cranking current required for cranking within a range that does not exceed the capacity of the backup power supply, and this does not lead to a shutdown of the backup power supply, allowing the engine to be restarted smoothly under idle stop control. [Brief description of the drawings]

[0016] [Figure 1] 1 is a block diagram of an embodiment of a vehicle control device of the present invention; [Diagram 2] 2 is a flowchart illustrating the operation of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] An embodiment of a vehicle control device according to the present invention will be described in detail with reference to Fig. 1 and Fig. 2. Fig. 1 is a block diagram of a vehicle control device mounted on a vehicle equipped with an idling stop control function, and Fig. 2 is a flowchart.

[0018] In Fig. 1, reference numeral 1 denotes a 12V battery comprised of a lead storage battery or the like mounted on a vehicle to supply power to various components, and 2 denotes a body ECU (Electronic Control Unit) which controls door lock / unlock control, seat control, light control, etc. In addition to controlling these body systems, the body ECU 2 also controls the battery voltage of the battery 1 by adding a predetermined backup voltage supplied to a boost circuit 3a of an HCU (Human Machine Interface Control Unit) 3 called an HMI integrated control unit, and also supplies a similar backup voltage to the battery voltage of the battery 1 to a number of other ECUs 5a, 5b, etc. Here, the body ECU 2 corresponds to the "backup power source" in this invention.

[0019] In Fig. 1, 6 is an idling stop ECU (hereinafter, idling stop will be referred to as "IDS"), which has a function of judging whether or not the engine (not shown) can be stopped by IDS control based on information such as the outside air temperature from an outside air temperature sensor (not shown), the state of charge of the battery 1, and the vehicle speed from a vehicle speed sensor (not shown), and has an IDS control function of stopping the engine when it is judged that the engine can be stopped and restarting the engine when a predetermined engine stop condition is satisfied and a predetermined engine restart condition is satisfied, respectively. Here, when IDSECU6 ​​judges that the vehicle is in a condition in which the engine cannot be stopped by IDS control, IDS control is not executed.

[0020] Then, the IDSECU 6 transmits an IDS state signal to a CPU 3b of the HCU 3, which will be described later, indicating that the engine is to be stopped by IDS control, or that the engine has been stopped by IDS control, etc. The above-mentioned determination function by the IDSECU 6 corresponds to the "determination unit" in this invention, and the above-mentioned IDS control function by the IDSECU 6 corresponds to the "idling stop control means" in this invention.

[0021] More specifically, based on information from the engine ECU that controls the engine (engine information such as engine speed and coolant temperature) via a CAN (Controller Area Network) communication bus not shown in FIG. 1, as well as information such as the current of the battery 1, outside air temperature information from an outside air temperature sensor, vehicle speed information from a vehicle speed sensor, and foot brake master cylinder pressure, the IDSECU 6 determines that the IDS control engine stop condition (for example, the stop lamp is on and the vehicle speed is below a predetermined vehicle speed, etc.) is met if it detects that the driver has depressed the brake pedal in response to a red traffic light or the like and the brake fluid pressure in the master cylinder is equal to or greater than a predetermined depression pressure, and if the vehicle speed drops below the predetermined vehicle speed even if it has not come to a complete stop, it commands the above-mentioned engine ECU to stop the engine, and the engine ECU automatically stops the engine by throttling the fuel throttle, for example.

[0022] On the other hand, when the engine is stopped by IDS control, and the driver takes his foot off the brake pedal because a traffic light turns green, for example, and the IDSECU 6 detects that the master cylinder pressure has dropped to a predetermined release pressure, it determines that the IDS control engine restart conditions (for example, the stop lamps are off and the doors are closed) are met, sends an engine restart command to the engine ECU, supplies power from the battery 1 to the starter motor (not shown), starts the starter motor, and automatically restarts the stopped engine.

[0023] Returning to Fig. 1, in addition to the boost circuit 3a described above, the HCU 3 includes a CPU 3b and an audio power amplifier 3c, which is one of the vehicle loads related to entertainment. The CPU 3b has a function of monitoring the current consumption of the power amplifier 3c, which is supplied with power from the battery 1 mounted on the vehicle, or from the battery 1 and the body ECU 2, which is a backup power source. Furthermore, the CPU 3b receives an IDS status signal from the IDSECU 6, such as stopping the engine under IDS control, or that the engine has been stopped under IDS control. This monitoring function by the CPU 3b corresponds to the "monitoring unit" in this invention.

[0024] The power amplifier 3c is normally supplied with a battery voltage B1 from the battery 1 via the boost circuit 3a, and during cranking to restart the engine under IDS control, a boosted voltage is supplied by adding a backup voltage B2 from the body ECU 2 to the battery voltage B1 from the battery 1 in order to ensure the cranking current required to drive the starter motor, and an audio signal is output to the speaker 8.

[0025] At this time, in a normal driving state where IDS control is not executed, the power amplifier 3c outputs the playback sound from the speaker 8 at a volume that is the output state set by the user by operating a volume setting switch (not shown), while in an IDS control state, the CPU 3b performs control to forcibly suppress the output state of the power amplifier 3c as follows. Such a control function of the output state of the power amplifier 3c by the CPU 3b corresponds to the "suppression unit" in this invention.

[0026] The CPU 3b monitors the amount of current used by the battery 1 mounted on the vehicle, or the battery 1 and the power amplifier 3c supplied with power by the body ECU 2, which is a backup power source, and the IDSECU 6 determines whether or not the engine can be stopped by IDS control based on information such as the outside air temperature from the outside air temperature sensor, the state of charge of the battery 1, and the vehicle speed from the vehicle speed sensor.If the result of this determination is that the engine can be stopped, the IDSECU 6 stops the engine by IDS control, or sends an IDS status signal to the CPU 3b indicating that the engine has been stopped by IDS control.

[0027] Then, when the CPU 3b receives an IDS status signal from the IDSECU 6, the CPU 3b supplies to the power amplifier 3c a boosted voltage (B1+B2) obtained by adding the backup voltage B2 of the body ECU 2 to the battery voltage B1 of the battery 1 using the boost circuit 3a. In this state in which the boosted voltage (B1+B2) is being supplied, the CPU 3b determines, based on the amount of current used by the power amplifier 3c being monitored, whether or not an output suppression condition for the power amplifier 3c has been established, which indicates that the output state of the power amplifier 3c should be forcibly suppressed and controlled in order to ensure the amount of cranking current, which is the drive current of the starter motor required for cranking during IDS-controlled engine restart, within a range that does not exceed the capacity of the backup power source by the body ECU 2.

[0028] That is, when the CPU 3b judges that the cranking current required for cranking can be secured at the time of engine restart under IDS control within the range not exceeding the backup capacity of the body ECU 2, which is the backup power source, without compulsorily suppressing the output state of the power amplifier 3c, it does not perform control such as compulsorily suppressing the output state of the power amplifier 3c. On the other hand, when the CPU 3b judges that the cranking current required for cranking cannot be secured at the time of engine restart under IDS control unless the output state of the power amplifier 3c is compulsorily suppressed, the backup capacity of the body ECU 2, which is the backup power source, is exceeded, the function as a backup power source is stopped, and the amount of cranking current required for cranking cannot be secured at the time of engine restart under IDS control, the CPU 3b performs control such as compulsorily suppressing the output state of the power amplifier 3c, thereby securing the amount of cranking current required for cranking at the time of engine restart under IDS control within the range not exceeding the power source capacity of the backup by the body ECU 2, thereby enabling smooth engine restart under IDS control.

[0029] Here, until the suppression control of the output state of the power amplifier 3c by the CPU 3b is completed, an engine restart prohibition request is transmitted from the CPU 3b to the IDSECU 6, and the engine is not restarted, and when the suppression control of the output state of the power amplifier 3c is completed, the transmission of the engine restart prohibition request from the CPU 3b to the IDSECU 6 is stopped, and the engine is allowed to be restarted. Also, if the output state of the power amplifier 3c is changed by the user operating the volume setting switch until the suppression control of the output state of the power amplifier 3c by the CPU 3b is completed, a fluctuation in the amount of current used may occur, so the user's operation of changing the output state of the power amplifier 3c is invalidated, and the amount of cranking current required for cranking is ensured when the engine is restarted under IDS control.

[0030] Incidentally, when IDSECU6 ​​determines that the vehicle is in a state in which the engine can be stopped by IDS control, the output state of the power amplifier 3c is forcibly controlled before the engine is actually stopped by IDS control based on the monitoring results of the amount of current usage being monitored. Therefore, even in a case where the engine is restarted in the shortest time (e.g., 32 msec) after the engine is stopped by IDS control, suppression of the output state of the power amplifier 3c is started early and the amount of cranking current required for cranking is secured, so that the engine can be restarted smoothly under IDS control.

[0031] Since the drive current of the starter motor required for cranking during engine restart can be experimentally obtained in advance, the obtained drive current amount is stored in a memory or the like as the cranking current amount, and the amount of current available for cranking can be calculated by subtracting the current usage amount of the power amplifier 3c being monitored from the upper current upper limit value obtained by supplying a voltage boosted by adding the backup voltage B2 to the battery voltage B1. In this way, depending on whether the calculated available current amount exceeds the cranking current amount read from the memory, it is possible to determine whether the amount of cranking current required for cranking during engine restart under IDS control can be secured within a range that does not exceed the backup capacity of the body ECU 2, which is the backup power source.

[0032] Next, the process of suppressing the output state of the power amplifier 3c will be described with reference to the flowchart of FIG.

[0033] 2, when the IG (ignition) switch is turned on, the CPU 3b starts to control the output state of the power amplifier 3c. Then, when the CPU 3b determines that the output state of the power amplifier 3c is not in a state to be automatically lowered (step S1), it determines whether the engine is stopped by IDS control or whether an IDS state signal indicating that the engine has been stopped by IDS control has been received from the IDSECU 6 (step S2).

[0034] If the IDS state signal has not been received and the determination result of step S2 is NO, the process returns to step S1. If the IDS state signal has been received and the determination result of step S2 is YES, in a state in which the boosted voltage (B1+B2) is being supplied, based on the current usage amount of the power amplifier 3c being monitored, in order to ensure the amount of cranking current, which is the drive current of the starter motor required for cranking at the time of engine restart under IDS control, within a range that does not exceed the power supply capacity of the backup by the body ECU 2, when an output suppression condition of the power amplifier 3c is established, the output state of the power amplifier 3c should be forcibly suppressed in order to ensure the amount of cranking current, which is the drive current of the starter motor required for cranking at the time of engine restart under IDS control, if the output state of the power amplifier 3c is not forcibly suppressed, the amount of cranking current required for cranking at the time of engine restart under IDS control cannot be ensured. Therefore, the CPU 3b determines a value of the output state of the power amplifier 3c (output guard value) that can ensure the amount of cranking current required for cranking, and the output state of the power amplifier 3c is automatically suppressed to the determined output guard value, and a change in the output state of the power amplifier 3c based on a user operation is prohibited (step S3).

[0035] Next, it is determined whether the suppression process of the output state of the power amplifier 3c is incomplete (step S4), and if the result of this determination is NO, that is, the suppression process is completed, the process returns to step S1; if the result of the determination is YES, that is, the suppression process is not completed, an engine restart prohibition request is sent from the CPU 3b to the IDSECU6, and the IDS-controlled engine restart by the IDSECU6 ​​is prohibited (step S5), and it is determined whether the IG switch has been turned off (step S6), and if the IG switch remains on and the result of the determination in step S6 is NO, the process returns to step S1; if the IG switch is turned off and the result of the determination in step S6 is YES, the suppression process of the output state of the power amplifier 3c is terminated.

[0036] Therefore, according to the above-described embodiment, when the IDSECU6 ​​determines that the engine can be stopped under IDS control, the CPU3b automatically suppresses and controls the output state of the power amplifier 3c based on the results of monitoring the amount of current used by the CPU3b so as to ensure the amount of cranking current required for cranking during engine restart under IDS control while not exceeding the power supply capacity of the backup by the body ECU2. Therefore, the amount of cranking current required for cranking under IDS control can be ensured within a range that does not exceed the power supply capacity of the backup by the body ECU2, and the engine can be restarted smoothly under IDS control without causing the backup power supply by the body ECU2 to be stopped.

[0037] Furthermore, based on the results of monitoring the amount of current used by the CPU 3b, the IDSECU 6 forcibly suppresses the output state of the power amplifier 3c before the engine is actually stopped by IDS control, so that even if the engine is restarted in the shortest time possible after being stopped by IDS control, the output state of the power amplifier 3c can be reliably suppressed and controlled to ensure the amount of cranking current required for cranking.

[0038] Furthermore, when the amount of cranking current for engine restart under IDS control can be secured by suppressing control of the output state of the power amplifier 3c, a signal permitting engine restart under IDS control is sent by the CPU 3b to the IDSECU 6, so that engine restart under IDS control can be performed smoothly.

[0039] In addition, if the amount of cranking current required for engine restart under IDS control cannot be secured even when the output state of the power amplifier 3c is suppressed, the CPU 3b sends an engine restart prohibition signal to the IDSECU 6. This prevents engine restart under IDS control and prevents the backup power supply from being stopped by the body ECU 2.

[0040] The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention.

[0041] For example, in the above embodiment, the entertainment-related in-vehicle load for which the output state is suppressed is described as a power amplifier 3c, but the entertainment-related in-vehicle load is not limited to the power amplifier 3c and may be a light such as an illumination decorative lamp.

[0042] Furthermore, in the above-described embodiment, when the CPU 3b can ensure the amount of cranking current during IDS-controlled engine restart by suppressing control of the output state of the power amplifier 3c, and even if there is a fluctuation in the amount of current used due to a user's operation to change the output state of the power amplifier 3c, as long as the amount of cranking current during engine restart can be ensured, the user may not be prohibited from changing the output state of the power amplifier 3c by operating a volume setting switch, for example.

[0043] This prevents the backup power supply by the body ECU 2, which is the backup power source, from being stopped, while allowing the user to change the output state of the power amplifier 3c, making it possible to output sound from the speaker at a volume that suits the user's preferences.

[0044] In the above embodiment, a case has been described in which IDSECU6 ​​forcibly suppresses the output state of the power amplifier 3c before the engine is actually stopped by IDS control based on the monitoring results of the amount of current used being monitored, but the output state of entertainment-related in-vehicle loads such as the power amplifier 3c may also be suppressed at the timing when the engine is actually stopped by IDS control.

[0045] Further, the backup power source is not limited to the body ECU 2 described above, and other power sources may be used.

[0046] Furthermore, the present invention can be applied to a vehicle control device that controls a vehicle equipped with an idling stop control means that stops the engine when specified engine stop conditions are met and restarts the engine when specified engine restart conditions are met. [Explanation of symbols]

[0047] 1 ... Battery 2 …Body ECU (backup power supply) 3b...CPU (monitoring section, control section) 3c ... Power amplifier (vehicle load)

Claims

1. A vehicle control device for controlling a vehicle having an idling stop control means for stopping an engine when a predetermined engine stop condition is satisfied and restarting the engine when a predetermined engine restart condition is satisfied, a monitoring unit that monitors the amount of current used by a battery mounted on the vehicle and a plurality of on-board loads that are supplied with power from a backup power source having a predetermined capacity, storing power boosted to a voltage higher than the voltage of the battery and suppressing a voltage drop during cranking to restart the engine; a suppression unit that suppresses an output state of an in-vehicle load related to entertainment of the vehicle among the plurality of in-vehicle loads based on a monitoring result of the amount of current used by the monitoring unit when the predetermined engine stop condition is established, so as not to exceed a capacity of the backup power supply; A vehicle control device comprising:

2. The suppression portion is sending an engine restart permission signal to the idling stop control means when the cranking current amount for restarting the engine can be secured by suppressing the output state of the on-board load related to the entertainment of the vehicle; When the cranking current amount for restarting the engine cannot be secured due to the suppression of the output state of the in-vehicle load related to the entertainment of the vehicle, a restart prohibition signal for the engine is transmitted to the idling stop control means. The vehicle control device according to claim 1 .

3. The suppression portion is The vehicle control device according to claim 1 or 2, characterized in that, when suppressing the output state of the vehicle load related to the vehicle's entertainment, a guard processing is performed to prevent the output of the vehicle load related to the entertainment from becoming greater than a predetermined state due to user operation.

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