JP2016156312A - Power generation voltage control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly perform in-traveling eco-run control without causing the deterioration of the drivability of a driver accompanied by a change of a power generation voltage of an alternator, and without causing a restart failure of an engine, related to a power generation voltage control device for a vehicle.SOLUTION: A power generation voltage control device for a vehicle which controls a power generation voltage of an alternator so that the power generation voltage reaches a prescribed target voltage at an engine restart at in-traveling eco-run control comprises control means which controls an indication value of the power generation voltage with respect to the alternator becomes smaller than a maximum value of a change speed at which it is determined that the change speed up to the target voltage does not affect the drivability of a driver after an execution condition of the in-traveling eco-run control is established, and that a time necessary for reaching the target voltage from a start of an engine automatic stop at the in-traveling eco-run control becomes shorter than a time minimally necessary for a start of the engine restart from the start of the engine automatic stop.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an apparatus for controlling a generated voltage of an alternator.

  2. Description of the Related Art Conventionally, there is known an eco-run system that performs eco-run control for automatically stopping a vehicle engine when a predetermined stop condition is satisfied and automatically restarting the vehicle engine when a predetermined restart condition is satisfied (for example, Patent Document 1). The eco-run system is not limited to one that performs eco-run control only while the vehicle is stopped (hereinafter referred to as parked eco-run control), but when the vehicle is traveling (for example, the vehicle speed drops below a predetermined vehicle speed). In some cases (hereinafter referred to as running eco-run control). If the eco-run control is executed while the vehicle is traveling at a high vehicle speed, the fuel consumption can be enhanced because the engine can be stopped and the fuel consumption can be suppressed while the vehicle is traveling.

JP 2007-218230 A

  By the way, during execution of the above-described eco-run control, it is conceivable to reduce the indicated value of the power generation voltage of the alternator mounted on the vehicle to a target voltage lower than the normal value. According to such a configuration, the engine load can be reduced when the indicated value of the generated voltage of the alternator is a small value at the restart after the engine is automatically stopped by the eco-run control. It can be prevented. However, after the start of execution of eco-run control, an excessive change (that is, a high-speed and large amount of change) when the indicated value of the generated voltage of the alternator is reduced to the target voltage will cause the vehicle to stop when the eco-run control is executed while the vehicle is stopped. However, when the running eco-run control is executed, the engine load is drastically reduced due to the large change speed of the generated voltage instruction value immediately before the execution. For this reason, in the configuration in which the indicated value of the generated voltage of the alternator is decreased at an excessive change rate, there is a possibility that the driver may feel idle and the drivability is deteriorated as the engine load rapidly decreases. .

  On the other hand, if the indicated value of the generated voltage of the alternator is gradually changed, the above-described deterioration in drivability can be suppressed. However, with such a gradual change in the generated voltage, it takes a long time for the indicated value of the generated voltage to reach the target voltage. There is a high possibility that the engine will be restarted before the target voltage is reached. For this reason, with such a gradual change in the generated voltage, an engine restart request may occur when the generated voltage of the alternator is not sufficiently lowered. As a result, there is a high possibility that the restart failure will occur. turn into.

  The present invention has been made in view of the above-mentioned points, and is suitable for an eco-run during running without causing deterioration of the drivability of the driver accompanying changes in the power generation voltage of the alternator and without causing poor restart of the engine. An object of the present invention is to provide a vehicular power generation voltage control apparatus capable of executing control.

  One aspect of the present invention is mounted on a vehicle that executes eco-run control during travel that automatically stops and restarts the engine during travel of the vehicle. A power generation voltage control device for a vehicle that controls a power generation voltage of an alternator so as to be a predetermined target voltage, and after an execution condition of the running eco-run control is satisfied, an indication value of the power generation voltage for the alternator is The target speed is changed from the start of the engine automatic stop in the running eco-run control so that the speed of change up to the target voltage is smaller than the maximum value of the speed of change determined not to affect the drivability of the driver. The time required to reach the voltage is shorter than the minimum required time from the start of the engine automatic stop to the start of engine restart. So that a generated voltage control device for a vehicle including control means for controlling.

  ADVANTAGE OF THE INVENTION According to this invention, eco-run control during driving | running | working can be performed appropriately, without causing the deterioration of a driver's drivability accompanying the change of the electric power generation voltage of an alternator, and causing the restart failure of an engine.

1 is a configuration diagram of a vehicular power generation voltage control apparatus according to an embodiment of the present invention. FIG. It is a flowchart of an example of the control routine performed in the vehicular power generation voltage control apparatus of the present embodiment. It is an operation | movement timing chart of an example in the vehicle generated voltage control apparatus of a present Example. It is an operation | movement timing chart of an example in the vehicle generated voltage control apparatus of a present Example.

  Hereinafter, specific embodiments of a vehicular generated voltage control apparatus according to the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration diagram of a vehicular generated voltage control apparatus 10 according to an embodiment of the present invention. The vehicle power generation voltage control device 10 of this embodiment includes an alternator (vehicle power generation device) 12 mounted on a vehicle, and controls an output voltage (power generation voltage) to be output to the alternator 12. The alternator 12 is a device that can generate electricity by rotation of an engine (internal combustion engine) mounted on a vehicle.

  In the present embodiment, the vehicle on which the alternator 12 is mounted is a vehicle capable of executing eco-run control (that is, idling stop control). The eco-run control is an engine that is a power source when a predetermined stop condition (for example, accelerator pedal off, brake pedal on, vehicle speed is reduced to a predetermined vehicle speed or lower, engine load is a predetermined value or lower, etc.) is satisfied. The engine is automatically restarted when a predetermined restart condition (for example, accelerator pedal on, brake pedal off, engine load increases, etc.) is satisfied. is there.

  In addition, the eco-run control executed by the vehicle in the present embodiment performs the engine automatic stop if other stop conditions are satisfied even during traveling of the vehicle before the vehicle stops (for example, when the vehicle speed is a predetermined vehicle speed or less), and thereafter At least the running eco-run control for restarting the engine if the restart condition is satisfied is included. The eco-run control may include a stop-time eco-run control in which the engine is automatically stopped if another stop condition is satisfied while the vehicle is stopped and the engine is restarted if the restart condition is subsequently satisfied. The running eco-run control allows the engine to be automatically stopped while the vehicle is running before the vehicle is stopped. Therefore, compared to the stopped eco-run control in which the engine is automatically stopped after the vehicle is stopped, the fuel efficiency of the vehicle is further improved. Can be planned.

  The vehicular power generation voltage control apparatus 10 includes an electronic control unit (hereinafter referred to as ECU) 14 that controls the power generation of the alternator 12. The ECU 14 is mainly composed of a microcomputer. The ECU 14 is connected to the alternator 12 and instructs the alternator 12 to generate power. The alternator 12 generates power in accordance with a power generation voltage instruction from the ECU 14.

  The ECU 14 has an idling stop permission determination unit 20. The idling stop permission determination unit 20 is input with information indicating a traveling state, information indicating a vehicle state, and information indicating a surrounding environment from a sensor or another ECU. The traveling state is a traveling state of the host vehicle, for example, a state indicated by a vehicle speed, an engine speed, an acceleration, and the like. The vehicle state is various states other than the traveling state in the host vehicle, such as a battery state (for example, remaining capacity), an electric load state, and the like. The surrounding environment is a state where the host vehicle is placed, and indicates, for example, the temperature, the position, the presence or absence of front and rear vehicles, and the like. The idling stop permission determination unit 20 determines whether or not the host vehicle is currently in a state in which the running eco-run control can be performed based on the traveling state, the vehicle state, and the surrounding environment.

  The ECU 14 has a generated voltage calculation unit 22. The power generation voltage calculation unit 22 receives information indicating the traveling state, information indicating the vehicle state, and information indicating the surrounding environment. The generated voltage calculation unit 22 calculates an instruction value of the generated voltage that should be output to the alternator 12 based on the traveling state, the vehicle state, and the surrounding environment. Note that the calculated power generation voltage instruction value varies depending on the state of the power generation voltage. For example, the power generation voltage instruction value increases as the current consumption of the in-vehicle electric load increases, and increases when the battery voltage decreases. Is set as follows. Further, the generated voltage instruction value can change frequently in response to the change in the state.

  The ECU 14 has a differential voltage calculation unit 24. The generated voltage calculation unit 22 is connected to the differential voltage calculation unit 24. Information indicating the power generation voltage instruction value calculated by the power generation voltage calculation unit 22 is input to the differential voltage calculation unit 24, and the engine is automatically stopped by the running eco-run control (that is, the engine is restarted from the automatic stop). ), Information indicating a target voltage (target voltage) is input as the power generation voltage of the alternator 12. The target voltage may be set to a predetermined value in advance. The differential voltage calculation unit 24 calculates a differential voltage between the generated voltage command value from the generated voltage calculation unit 22 and the target voltage value (that is, the differential voltage of the current generated voltage command value with respect to the target voltage).

  The ECU 14 has a maximum change speed calculation unit 26. The maximum change speed calculation unit 26 receives information indicating the traveling state, information indicating the vehicle state, and information indicating the surrounding environment. The maximum change speed calculation unit 26 can determine that the drivability of the alternator 12 does not affect the drivability of the driver based on the traveling state, the vehicle state, and the surrounding environment. A maximum value (hereinafter referred to as a maximum change rate) of a change rate (that is, a change amount per unit time) that decreases with the calculation is calculated.

  There is a correlation between the change rate of the generated voltage of the alternator 12 and the acceleration or jerk of the vehicle. The maximum change rate of the generated voltage calculated as described above varies depending on the traveling state, the vehicle state, and the surrounding environment. For example, the maximum change rate of the generated voltage is set so that the value thereof increases as the acceleration of the vehicle increases. The maximum change rate of the generated voltage is based on the current vehicle acceleration and the change in vehicle acceleration with respect to the change rate of the generated voltage, so that the change in vehicle acceleration from the current vehicle acceleration does not affect the drivability of the driver. It is set within a range not exceeding the maximum value (threshold value) of vehicle acceleration change that can be determined.

  The ECU 14 has a change time calculation unit 28. The change time calculation unit 28 is connected to the differential voltage calculation unit 24 and the maximum change rate calculation unit 26. Information indicating the difference voltage of the current generated voltage instruction value with respect to the target voltage calculated by the difference voltage calculation unit 24 is input to the change time calculation unit 28 and the maximum change rate calculated by the maximum change rate calculation unit 26 is input. The information shown is input. The change time calculation unit 28 is a time required to reduce (change) the generated voltage of the alternator 12 by the difference voltage of the current generated voltage instruction value with respect to the target voltage at the maximum change rate (hereinafter referred to as a difference voltage change time). ) Is calculated.

  The ECU 14 has a restart time calculation unit 30. The idling stop permission determination unit 20 is connected to the restart time calculation unit 30. Information indicating whether or not the host vehicle determined by the idling stop permission determination unit 20 is in a state where the running eco-run control can be executed is input to the restart time calculation unit 30. When it is determined that the host vehicle is currently in a state where the running eco-run control can be executed, the restart time calculation unit 30 starts the running eco-run control (that is, starts the engine automatic stop) and then runs the running eco-run. A minimum required time (hereinafter referred to as a restart required time) until the end of control (that is, the start of engine restart) is calculated. The time required for restart may be determined in advance from the hardware configuration of the vehicle in executing the eco-run control during traveling, and may be determined depending on the traveling state of the vehicle, the vehicle state, and the surrounding environment. It may be calculated based on this.

  The ECU 14 has a time comparison unit 32. The time comparison unit 32 is connected to the change time calculation unit 28 and the restart time calculation unit 30. Information indicating the differential voltage change time calculated by the change time calculation unit 28 is input to the time comparison unit 32, and information indicating the restart required time calculated by the restart time calculation unit 30 is input to the time comparison unit 32. The time comparison unit 32 compares the difference voltage change time and the restart required time to obtain a magnitude relationship.

  The ECU 14 has a generated voltage recalculation unit 34. The power generation voltage recalculation unit 34 is connected to the time comparison unit 32 and the power generation voltage calculation unit 22. Information indicating the result of comparison by the time comparison unit 32 is input to the generated voltage recalculation unit 34. The generated voltage recalculation unit 34 recalculates the generated voltage instruction value to be output to the alternator 12 based on the comparison result in the time comparison unit 32, and calculates the recalculated generated voltage instruction value as the generated voltage. Feedback to the unit 22.

  The indicated value of the generated voltage of the alternator 12 calculated by the generated voltage calculation unit 22 or the generated voltage recalculation unit 34 of the ECU 14 is supplied to the alternator 12. The alternator 12 generates power in accordance with the indicated value of the generated voltage from the ECU 14.

  Next, with reference to FIGS. 2 to 4, the operation of the vehicular power generation voltage control apparatus 10 according to the present embodiment will be described.

  FIG. 2 shows a flowchart of an example of a control routine executed in the vehicular power generation voltage control apparatus 10 of this embodiment. FIG. 3 shows an example timing chart realized in the vehicular power generation voltage control apparatus 10 of the present embodiment. FIG. 4 shows an example timing chart realized in the vehicle power generation voltage control apparatus 10 of the present embodiment.

  In the vehicular power generation voltage control apparatus 10 of the present embodiment, the ECU 14 executes the control routine shown in FIG. 2 when the ignition switch of the vehicle is turned on (specifically, when the vehicle is switched from off to on). Start.

  First, the ECU 14 uses the generated voltage calculation unit 22 to calculate the instruction value Vco of the generated voltage that should be output to the alternator 12 at present (step 100). The calculation value Vco of the generated voltage is calculated based on the running state of the vehicle, the vehicle state, and the surrounding environment that are input from sensors, other ECUs, and the like. Next, the ECU 14 calculates a difference voltage ΔV between the generated voltage instruction value Vco and the target voltage V0 in the difference voltage calculation unit 24 (step 102). This difference voltage ΔV is a voltage that represents the difference between the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22 and the target voltage V0 that is the target as the generated voltage of the alternator 12 during automatic engine stop.

  Then, the ECU 14 determines whether or not the difference voltage ΔV between the generated voltage instruction value Vco calculated in step 102 and the target voltage V0 is not substantially zero, that is, whether or not the generated voltage instruction value Vco and the target voltage V0 are significantly different. A determination is made (step 104). If the difference voltage ΔV is substantially zero, it takes a long time without affecting the driver's drivability to change the generated voltage of the alternator 12 from the indicated value Vco to the target voltage V0. Therefore, there is not much problem even if the alternator 12 is caused to generate power with the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22. Therefore, if the ECU 14 determines in step 104 that the differential voltage ΔV is substantially zero, next, the ECU 14 causes the alternator 12 to generate power using the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22 in step 100. Therefore, a power generation instruction is given to the alternator 12 (step 106). In this case, the alternator 12 performs power generation according to the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22.

  On the other hand, if the ECU 14 determines in step 104 that the differential voltage ΔV is not substantially zero, the ECU 14 next calculates a maximum change rate SPDmax in the maximum change rate calculator 26 (step 108). This maximum change speed SPDmax is the maximum value of the change speed at which the power generation voltage of the alternator 12 can be determined not to affect the drivability of the driver and decreases with time. The calculation of the maximum change speed SPDmax is performed based on the running state of the vehicle, the vehicle state, and the surrounding environment input from sensors, other ECUs, and the like.

  Next, the ECU 14 calculates the difference voltage change time T1 in the change time calculation unit 28 (step 110). This difference voltage change time T1 is a time required to change the generated voltage of the alternator 12 by the difference voltage ΔV from the current generated voltage instruction value Vco to the target voltage V0 at the maximum change rate SPDmax. The difference voltage change time T1 is calculated by calculating the maximum change rate SPDmax calculated by the maximum change rate calculating unit 26 and the difference voltage ΔV between the generated voltage command value Vco calculated by the difference voltage calculating unit 24 and the target voltage V0. Based on.

  The ECU 14 automatically stops the engine in the idling stop permission determination unit 20 as to whether or not the host vehicle is currently in a state where the running eco-run control (idling stop control) can be executed. It is determined whether or not a predetermined stop condition is satisfied (step 112). This determination is made based on the running state of the vehicle, the vehicle state, and the surrounding environment that are input from sensors, other ECUs, and the like.

  If the ECU 14 determines in step 112 that the host vehicle is not currently in a state where it can execute the running eco-run control, the ECU 14 then uses the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22 in step 100. In order to generate power from the alternator 12, a power generation instruction is issued to the alternator 12 (step 106). In this case, the alternator 12 performs power generation according to the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22.

  On the other hand, if the ECU 14 determines in step 112 that the host vehicle is currently in a state where the running eco-run control can be performed, the restart time calculation unit 30 calculates the restart required time T2. (Step 114). This restart required time T2 is the minimum necessary time from the start of the running eco-run control (that is, the start of the automatic engine stop) to the end of the running eco-run control (ie, the start of the engine restart). . This restart required time T2 may be determined in advance, or may be calculated based on the current running state of the vehicle, the vehicle state, and the surrounding environment.

  Next, the ECU 14 uses the time comparison unit 32 to calculate the differential voltage change time T1 calculated by the change time calculation unit 28 in step 110 and the required restart time T2 calculated by the restart time calculation unit 30 in step 114. To determine whether or not the differential voltage change time T1 is longer than the restart required time T2 (step 116).

  If the ECU 14 determines in step 116 that the difference voltage change time T1 is not longer than the restart required time T2, the ECU 14 then uses the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22 in step 100. In order to generate power from the alternator 12, a power generation instruction is issued to the alternator 12 (step 106). This is because, when T1 ≦ T2 is satisfied, the power generation voltage of the alternator 12 changes from the current instruction value Vco calculated by the power generation voltage calculation unit 22 after the automatic stop of the engine by the running eco-run control is started. When the speed SPDmax is reduced (changed), the target voltage V0 can be reached within the above-described restart required time T2 (that is, up to the shortest timing at which the engine is restarted). This is because there is no need to reduce the indicated value Vco of the generated voltage before the automatic stop is started. In this case, the alternator 12 performs power generation according to the generated voltage instruction value Vco calculated by the generated voltage calculation unit 22.

  On the other hand, if the ECU 14 determines that the differential voltage change time T1 is longer than the restart required time T2 in step 116, the generated voltage recalculation unit 34 causes the alternator 12 to output the indicated value Vco of the generated voltage. 'Is recalculated (step 118). The recalculated command value Vco 'of the generated voltage is the command value Vco that can reach the target voltage V0 within the restart required time T2 if the command value Vco' is reduced from the command value Vco 'at the maximum change speed SPDmax. Preferably, it may be the maximum value among the indicated values Vco.

  When the generated voltage recalculation unit 34 recalculates the generated voltage instruction value Vco ′ in step 118, the ECU 14 then changes the generated voltage instruction value Vco to the recalculated generated voltage instruction value Vco ′. In order to cause the alternator 12 to generate power at the indicated value Vco while decreasing (changing) at the maximum change speed SPDmax, a power generation instruction is issued to the alternator 12 (step 106). In this case, the alternator 12 performs power generation in accordance with the power generation voltage instruction value Vco that is calculated by the power generation voltage recalculation unit 34 and is reduced at the maximum change rate SPDmax.

  In addition, as a method of lowering the command value Vco of the generated voltage at the maximum change speed SPDmax, the command value Vco may be lowered linearly with the passage of time, or the driver may be trained with the passage of time. The instruction value Vco may be decreased stepwise within a range that does not affect the drivability of the device.

  Further, in order to reduce the indicated value Vco of the generated voltage of the alternator 12 to the target voltage V0 via the indicated value Vco ′ of the generated voltage recalculated as described above, as shown in FIG. After the decrease starts at time ta, the running eco-run control (automatic engine stop) is started at the time tb when the command value Vco reaches the recalculated command value Vco ', and the command value Vco is maximized. It is good also as reducing to target voltage V0 with change speed SPDmax. Alternatively, as shown in FIG. 4, after the instruction value Vco starts decreasing at time ta, the instruction value Vco stops decreasing at time tb when the instruction value Vco reaches the recalculated instruction value Vco ′. Thereafter, the running eco-run control (automatic engine stop) is started at a time point tc when a predetermined time has elapsed, and the indicated value Vco may be decreased to the target voltage V0 at the maximum change speed SPDmax.

  The ECU 14 continuously performs the processing after each step 100 as long as the ignition switch of the vehicle is turned on. Then, the ECU 14 ends the execution of the control routine shown in FIG. 2 when the ignition switch of the vehicle is turned off (specifically, when the vehicle is switched from on to off).

  Thus, in the vehicle power generation voltage control apparatus 10 of the present embodiment, in principle, the power generation voltage instruction value Vco of the alternator 12 is calculated based on the vehicle running state, the vehicle state, and the surrounding environment. Can be set to Further, when there is a differential voltage ΔV between the current value of the indicated value Vco of the generated voltage of the alternator 12 and the target voltage V0 during the automatic engine stop, the indicated value Vco is changed by the differential voltage ΔV at the maximum change rate SPDmax. When the difference voltage change time T1 required for the engine is longer than the minimum required restart time T2 from the start of the engine automatic stop to the start of the engine restart in the running eco-run control, the indicated value of the generated voltage of the alternator 12 Vco can be set as follows.

  That is, the indicated value Vco is first changed from the current value based on the running state of the vehicle, the vehicle state, and the surrounding environment to the instructed value Vco ′ at the maximum change speed SPDmax, and thereafter, the running eco-run control (engine (Automatic stop) can be started, and the command value Vco ′ can be changed at the maximum change speed SPDmax from the target value Vco ′ to the target voltage V0 that is the target during the automatic engine stop.

  In such a configuration, the generated voltage of the alternator 12 has a change amount per unit time from the current value to the target voltage smaller than the maximum change speed SPDmax, and the target voltage from the start of the engine automatic stop in the running eco-run control. The time required to reach the time is controlled to be shorter than the restart required time T2.

  According to this configuration, since the generated voltage of the alternator 12 is changed in advance so that the differential pressure with respect to the target voltage becomes small before the running eco-run control is started (before the engine automatic stop is started), the running eco-run control is executed. In the middle, it is possible to avoid an excessive change (that is, a high speed and a large amount of change) when the generated voltage of the alternator 12 is changed to the target voltage. For this reason, it is possible to prevent the driver from feeling idle during a rapid change in the engine load during the execution of the eco-run control during traveling, and it is possible to prevent the drivability from being deteriorated.

  Moreover, according to said structure, the electric power generation voltage of the alternator 12 can be reduced to a target voltage at least by the start point of engine restart after the start of the engine automatic stop in the running eco-run control. That is, it is possible to avoid that the engine restart is allowed before the generated voltage of the alternator 12 reaches the target voltage. For this reason, since the engine can be restarted after the power generation voltage of the alternator 12 is sufficiently lowered, it is possible to avoid the occurrence of a restart failure of the engine.

  Therefore, according to the vehicle power generation voltage control apparatus 10 of the present embodiment, the driver drivability is not deteriorated due to the change in the power generation voltage of the alternator 12, and the engine restart failure is not appropriately caused. It is possible to execute eco-run control during traveling.

  In this embodiment, the timing for changing the power generation voltage of the alternator 12 in advance so that the differential pressure from the target voltage becomes small before the start of the running eco-run control (before the start of the engine automatic stop) is the running eco-run control. This is after a predetermined stop condition for automatically stopping the engine is established. For this reason, it is not necessary to change the power generation voltage of the alternator 12 in advance so that the differential pressure from the target voltage becomes small before the predetermined stop condition in the running eco-run control is satisfied, so that the power generation voltage of the alternator 12 is normally used. Sometimes it can be prevented from being excessively suppressed.

  In the above embodiment, the target voltage that is the target as the power generation voltage of the alternator 12 during the automatic stop of the engine by the eco-run control during traveling (that is, when the engine is restarted from the automatic stop) is within the scope of the claims. The ECU 14 corresponds to the “predetermined target voltage” described above and the “control means” described in the claims.

  By the way, in the above embodiment, the indicated value Vco of the generated voltage of the alternator 12 calculated based on the running state of the vehicle, the vehicle state, and the surrounding environment is the target voltage V0 during the automatic engine stop in the running eco-run control. Assuming a higher value, the indicated value Vco of the generated voltage is reduced to the target voltage V0 side. However, the present invention is not limited to this, as long as the generated voltage of the alternator 12 is changed in advance so that the differential pressure from the target voltage is reduced. That is, when the indicated value Vco of the generated voltage of the alternator 12 calculated based on the running state of the vehicle, the vehicle state, and the surrounding environment is lower than the target voltage V0 during the engine automatic stop in the running eco-run control, The generated voltage instruction value Vco may be increased toward the target voltage V0.

  Further, in the above-described embodiment, the required restart time T2 is from the start of the running eco-run control (that is, the start of the engine automatic stop) to the end of the running eco-run control (ie, the start of the engine restart). However, it is also possible to learn and update the restart required time T2 as vehicle user information. According to such a modification, the restart required time T2 can be lengthened, so that the power generation voltage of the alternator 12 from the target voltage in advance before the start of the running eco-run control (before the start of the engine automatic stop) is increased. It is possible to reduce the frequency of change so as to decrease, and to reduce the fuel efficiency effect by the eco-run control during traveling as much as possible.

DESCRIPTION OF SYMBOLS 10 Vehicle power generation voltage control apparatus 12 Alternator 14 Electronic control unit (ECU)

Claims (1)

The vehicle is mounted on a vehicle that executes eco-run control during traveling that automatically stops and restarts the engine while the vehicle is traveling, so that a predetermined target voltage is obtained when the engine is restarted in the eco-run control during travel. A vehicle power generation voltage control device for controlling the power generation voltage of the alternator,
After the execution condition of the running eco-run control is established, the indicated value of the generated voltage for the alternator is changed to a change speed at which the change speed to the target voltage is determined not to affect the drivability of the driver. The time required to reach the target voltage from the start of the engine automatic stop in the traveling eco-run control to be smaller than the maximum value is the minimum from the start of the engine automatic stop to the start of engine restart. A vehicular power generation voltage control device comprising a control means for controlling so as to be shorter than a limited necessary time.

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