JP2006316671A - Control device of generator for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve energy regeneration efficiency at a time of vehicle braking without sacrificing regeneration of braking energy when braking energy at a time of vehicle braking is regenerated by voltage control of a generator in a vehicle provided with an automatic stop control means automatically stopping the engine when an engine stop condition is established at a time of vehicle stop. <P>SOLUTION: A voltage control part 11 controlling output voltage of the generator 20 driven by the engine and supplying electric power to a battery 21 and a vehicular electric load 22 to Hi voltage if a predetermined vehicle deceleration condition is detected and to Lo voltage if the predetermined vehicle deceleration is not detected, and an automatic stop estimation part 14 estimating whether a navigation stop condition is established or not based on road environment information acquired by a navigation device 35 when predetermined deceleration condition is detected are provided. Output voltage of the generator is controlled to Hi voltage until engine automatic stop is performed if establishment of engine stop condition is estimated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control device for a vehicular generator that controls a dynamo that is driven by an engine and can supply power to an on-vehicle battery and an electric load for the vehicle.

  As a control device for such a vehicle generator, while the power generation voltage of the generator during vehicle travel was conventionally controlled to be constant, the power generation voltage of the generator is increased when the vehicle is in a deceleration state, When the vehicle is not in a decelerating state (that is, in a non-decelerating state), a configuration is known in which control is performed to reduce the generated voltage (see, for example, Patent Document 1).

  By controlling the power generation voltage of the generator in this way, the amount of power generated by the generator increases when the vehicle is decelerated, and the charging of the battery is promoted, while the amount of power generated by the generator decreases when the vehicle is not decelerated. And charging to the battery is suppressed. Thereby, the regeneration of the braking energy at the time of vehicle braking can be achieved, and as a result, the fuel consumption characteristics of the engine can be improved.

  In recent years, there has been a strong demand for further improvement of the fuel consumption characteristics of automobiles due to the further increase in environmental problems. A so-called fuel cutoff control is known in which fuel supply is cut off (cut) in a predetermined deceleration region that is not required. In such fuel shut-off control, fuel cut is performed when the vehicle enters the predetermined deceleration region, but when the engine speed decreases to a predetermined fuel return speed (usually set near the idle speed), so-called fuel cut-off control is performed. In order to avoid engine stalls, fuel supply is usually resumed.

  In a vehicle equipped with an engine for performing such fuel cutoff control, when performing voltage control for regenerating braking energy during vehicle deceleration as described above for the output voltage of the generator, as shown in FIG. When entering the deceleration state, the power generation voltage of the generator is changed from the Lo voltage in the non-deceleration state (a relatively low power generation voltage that suppresses charging of the battery) to the Hi voltage (a relatively high power generation voltage that promotes charging of the battery). (See the broken line of the solid line in FIG. 3) However, when the vehicle speed decreases until the engine speed reaches the fuel return speed, the engine stall is also avoided as shown by the broken line in FIG. Therefore, conventionally, it is common to control the power generation voltage of the generator so as to decrease from the Hi voltage to the Lo voltage.

  That is, in this prior art, when the vehicle speed decreases until the engine speed reaches the fuel return speed, regardless of whether the engine is subsequently idled or stopped, Is switched from the Hi voltage to the Lo voltage, and regeneration of braking energy during vehicle braking is suppressed. That is, the regeneration of the braking energy is suppressed by an amount corresponding to the region Ed surrounded by the broken line and the broken line in FIG.

By the way, in recent years, as disclosed in, for example, Patent Document 2, when the engine stop condition is satisfied in a state where the vehicle is stopped and the engine is rotating, the engine is automatically stopped. An engine control system with a stop function is being developed.
JP-A-5-137275 JP-A-10-299531

  However, in the prior art, when the vehicle speed decreases until the engine speed reaches the fuel return speed, the braking at the time of vehicle braking is performed regardless of whether the engine is idled or stopped thereafter. Since the regeneration of energy is suppressed, in the engine control system having the idle stop function, the regeneration of braking energy is suppressed even when the engine stop condition is satisfied and the engine is automatically stopped. .

  That is, in the above-described prior art, even when the engine is automatically stopped when the engine stop condition is satisfied, the braking energy is equivalent to the area Ed surrounded by the broken line and the broken line in FIG. Regeneration has to be sacrificed, and there is a problem that the energy regeneration efficiency at the time of vehicle braking is lowered accordingly.

  In view of this, the present invention provides a vehicle equipped with automatic stop control means for automatically stopping the engine when the engine stop condition is satisfied when the vehicle is stopped. The purpose of this is to increase the energy regeneration efficiency during vehicle braking as much as possible without sacrificing the regeneration of braking energy as much as possible.

  For this reason, the control device for a vehicular generator according to the invention of claim 1 of the present application (the first invention) is a navigation device capable of obtaining road environment information related to the road environment of the traveling road in the traveling direction of the host vehicle. It is equipped with a vehicle having an automatic stop control means for automatically stopping the engine when the engine stop condition is satisfied when the vehicle is stopped, and can be driven by the engine to supply electric power to the on-vehicle battery and the vehicle electric load. A control device for a vehicular generator that controls a generator, an operating state detecting means for detecting a driving state of the vehicle, a first voltage for promoting charging of the battery, and a second voltage for suppressing charging of the battery The output voltage of the generator can be controlled at the same time, and when a predetermined deceleration state is detected for the driving state of the vehicle, the generator output voltage is controlled to the first voltage, and the predetermined deceleration state is detected. If not, voltage control means for controlling the output voltage of the generator to the second voltage, and the road environment information obtained by the navigation device when a predetermined deceleration state is detected for the driving state of the vehicle And automatic stop prediction means for predicting whether or not the engine stop condition is satisfied based on the above. When the automatic stop prediction unit predicts that the engine stop condition is satisfied, the output voltage of the generator is controlled to the first voltage until the automatic stop of the engine is performed by the automatic stop control unit. It is characterized by that.

  The invention according to claim 2 of the present application (the second invention) is characterized in that, in the first invention, when a predetermined deceleration state is detected for the driving state of the vehicle, the fuel supply to the engine is stopped and the engine When the rotational speed decreases to a preset fuel return engine rotational speed, a deceleration fuel supply control means for starting fuel supply to the engine is provided in the vehicle, and the voltage control means is provided by an automatic stop prediction means. When the engine stop condition is predicted to be satisfied and the engine speed has decreased to the fuel return engine speed, the output voltage of the generator is set lower than the first voltage and higher than the second voltage. It is characterized by controlling to 3 voltages.

  Further, the invention of claim 3 of the present application (third invention) is that, in the second invention, the voltage control at the third voltage is continued until the engine automatic stop by the automatic stop control means is performed. It is a feature.

According to the first invention of the present application, when a predetermined deceleration state is detected for the driving state of the vehicle, the output voltage of the generator is controlled to the first voltage that promotes charging of the battery, and the predetermined deceleration state is achieved. When the engine is not detected, the output voltage of the generator is controlled to the second voltage that suppresses the charging of the battery, so that the braking energy is regenerated during braking of the vehicle, thereby improving the fuel efficiency characteristics of the engine. be able to.
In addition, when a predetermined deceleration state is detected for the driving state of the vehicle, based on road environment information related to the road environment of the traveling path in the traveling direction of the host vehicle obtained by the navigation device equipped on the vehicle, Whether or not the engine stop condition is satisfied is predicted by the automatic stop prediction means, and when the engine stop condition is predicted to be satisfied, the output voltage of the generator is output until the engine is automatically stopped by the automatic stop control means. Is controlled to the first voltage. Therefore, when it is predicted that the engine stop condition is not satisfied, the output voltage control of the generator is reliably performed according to the deceleration state of the vehicle, while when the engine stop condition is predicted to be satisfied. Until the engine is automatically stopped by the automatic stop control means, the output voltage of the generator is controlled to the first voltage, so that regeneration of braking energy is not sacrificed and braking during vehicle braking is performed. Higher regeneration efficiency can be obtained for energy regeneration.

In addition, according to the second invention of the present application, basically, the same operational effects as the first invention can be achieved. In particular, the vehicle is provided with a deceleration fuel supply control means, and when a predetermined deceleration state is detected with respect to the driving state of the vehicle, the fuel supply to the engine is stopped, and a fuel return engine in which the engine speed is preset. Since the fuel supply to the engine is started when the engine speed decreases, the fuel consumption characteristics can be further improved, and so-called engine stall can be avoided.
In particular, when the engine stop condition is predicted to be satisfied by the automatic stop predicting means and the engine speed has decreased to the fuel return engine speed, the voltage control means sets the output voltage of the generator to the first. Since the third voltage is controlled to be lower than the second voltage and higher than the second voltage, when the engine speed is reduced to the fuel return engine speed and the engine stall is more likely to occur, the output voltage of the generator is set higher than the first voltage. By controlling the output voltage to a third voltage lower than the second voltage, the output voltage of the generator is lowered below the first voltage to reduce the engine load accordingly, and the risk of engine stall is more effectively suppressed. In addition, it is possible to ensure a certain regenerative efficiency improvement effect for the regeneration of braking energy during vehicle braking.

  Furthermore, according to the third invention of the present application, basically the same function and effect as those of the second invention can be achieved. In particular, by continuing the voltage control with the third voltage until the engine is automatically stopped by the automatic stop control means, the risk of engine stall can be more effectively suppressed until the engine is automatically stopped, and vehicle braking is performed. A certain regeneration efficiency improvement effect can be ensured for the regeneration of braking energy at the time, which can contribute to the improvement of the fuel consumption characteristics of the vehicle.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a block diagram schematically showing the configuration of the vehicle engine control system according to the present embodiment. This engine control system has an automatic stop control function for automatically stopping the engine when an engine stop condition is satisfied when the vehicle is stopped.

  As shown in FIG. 1, the engine control system includes a control unit 10 (engine control unit) configured, for example, with a microcomputer as a main part, and an on-vehicle generator 20 (so-called “so-called”) with respect to the engine control unit 10. , An alternator) is connected so as to be able to send and receive signals. A vehicle-mounted battery 21 and various vehicle electrical loads 22 are electrically connected to the generator 20.

  The generator 20 is driven by a vehicle engine (not shown) and can supply power to the battery 21 and the vehicle electrical load 22, and the structure and operation thereof are the same as those well known in the art. Is. The battery 21 is, for example, a so-called lead battery using sulfuric acid as an electrolytic solution, and this is the same as a conventionally known battery.

  The engine control unit 10 is connected to a fuel injection valve 26 for injecting and supplying fuel to the engine and an ignition plug 27 for igniting an air-fuel mixture in the engine combustion chamber so as to be able to exchange signals. These fuel injection valve 26 and spark plug 27 are the same as those conventionally known.

  Further, the engine control unit 10 is connected to various sensors and devices for detecting the driving state of the vehicle, the road environment of the traveling road in the traveling direction of the vehicle, and the like. That is, an engine speed sensor 31 that detects the engine speed, an accelerator position sensor 32 (throttle position sensor) that detects the accelerator position (for example, the throttle valve position of the engine intake passage), and the vehicle speed of the host vehicle A vehicle speed sensor 33 for detecting the vehicle brake and a brake switch 34 for detecting the presence or absence of a vehicle braking operation by the brake device are connected to the engine control unit 10 so as to be able to send and receive signals. These sensors and switches are all the same as those conventionally known.

  From the accelerator opening detected by the accelerator opening sensor 32 and the vehicle speed detected by the vehicle speed sensor 33, it is possible to know whether or not the driving state of the vehicle is a deceleration state. That is, when the accelerator opening is zero and the vehicle speed is not zero, it can be determined that the driving state of the vehicle is a deceleration state. On the other hand, when the above conditions are not satisfied with respect to the accelerator opening and the vehicle speed, it can be determined that the driving state of the vehicle is not a deceleration state (non-deceleration state).

  Furthermore, a so-called navigation device 35 is connected to the engine control unit 10 so as to be able to exchange signals. The navigation device 35 is also similar to a conventionally known device, and includes, for example, a display (display) unit 35a and an information processing unit 35b, and receives a signal from an artificial satellite with a satellite receiving antenna (not shown). Thus, the current position of the host vehicle can be calculated, and the current position of the host vehicle and the traveling direction of the host vehicle can be displayed on the map of the display unit 35a. It is also possible to receive road environment information such as accident information, traffic regulation information or traffic jam information transmitted from a so-called beacon installed on the side of the road. Furthermore, the distance to the intersection in the traveling direction of the vehicle can be calculated based on the current position of the vehicle and the map information. In this way, the navigation device 35 can obtain road environment information related to the road environment of the travel path in the traveling direction of the host vehicle, and all the above information is transmitted to the engine control unit 10.

More preferably, the control unit 10 includes therein a voltage control unit 11, a deceleration fuel injection control unit 12, a deceleration state detection unit 13, an automatic stop prediction unit 14, and an automatic stop control unit 15.
The voltage control unit 11 controls the output voltage of the generator 20, and basically a first voltage (Hi voltage) that promotes charging of the battery 21 and a second voltage that suppresses charging of the battery 21. The output voltage of the generator 20 can be controlled to a voltage (Lo voltage). In particular, as shown by a solid broken line in FIG. 3, when a predetermined deceleration state is detected for the driving state of the vehicle. The output voltage of the generator 20 is controlled to the Hi voltage, and when the predetermined deceleration state is not detected, the output voltage of the generator 20 is controlled to the Lo voltage. The generator 20 is specifically connected to the voltage control unit 11 so as to be able to send and receive signals.

In the present embodiment, the Hi voltage that promotes charging of the battery 21 and the Lo voltage that suppresses charging of the battery 21 are set to 14 volts and 12.5 volts, for example.
In the control state at the Lo voltage, the output voltage of the generator 20 is equal to or lower than the voltage of the battery 21, the charging from the generator 20 to the battery 21 is not performed, and there is a power supply request from the vehicle electrical load 22. In this case, the electric discharge from the battery 21 to the vehicle electrical load 22 is expected instead of the generator 20.

  In this way, when a predetermined deceleration state is detected for the driving state of the vehicle, the output voltage of the generator 20 is controlled to a Hi voltage that promotes charging of the battery 21, and the predetermined deceleration state is not detected. In this case, by controlling the output voltage of the generator 20 to the Lo voltage that suppresses the charging of the battery 21, it is possible to regenerate braking energy during vehicle braking and thus improve the fuel consumption characteristics of the engine.

As will be described later, in the present embodiment, a third voltage (Mid voltage: 13 for example) is used between the Hi voltage and the Lo voltage in order to accelerate charging of the battery 21 to a certain extent, although not as much as when the Hi voltage. Volt) is set, and the voltage control unit 11 can control the output voltage of the generator 20 to any one of the Hi, Mid, and Lo.
The voltage control to the Hi, Mid, and Lo voltages as described above is performed, for example, by controlling the output voltage of the generator 20 by duty-controlling the current flowing in the so-called field coil of the generator 20 by the voltage control unit 11. Done. That is, as the field coil current increases, the output voltage increases.

  The deceleration fuel injection control unit 12 controls the fuel injection valve 26 when the vehicle is in a decelerating state, thereby controlling the injection amount and injection timing of fuel supplied to the engine. In the present embodiment, when a predetermined deceleration state is detected for the driving state of the vehicle, the fuel supply to the engine is stopped (that is, the fuel injection amount by the fuel injection valve 26 is controlled to be zero). At the same time, when the engine speed decreases to a preset fuel return engine speed, a control signal is output to the fuel injection valve 26 so as to start fuel supply to the engine.

  As described above, when a predetermined deceleration state is detected for the driving state of the vehicle, the fuel supply to the engine is stopped, and when the engine speed is reduced to a preset fuel return engine speed, the fuel supply to the engine is stopped. By being started, the fuel consumption characteristics can be further improved and so-called engine stall can be avoided. The fuel return engine speed is set slightly higher than the so-called idle speed.

  The deceleration state detection unit 13 detects whether or not the driving state of the vehicle is a predetermined deceleration state based on the accelerator opening detected by the accelerator opening sensor 32 and the vehicle speed detected by the vehicle speed sensor 33. It is. In the deceleration state detection unit 13, as described above, when the accelerator opening is zero and the vehicle speed is not zero, it is determined that the driving state of the vehicle is in a deceleration state. When the above condition is not satisfied, it is determined that the driving state of the vehicle is not a deceleration state (non-deceleration state). The detection signal of the deceleration state detection unit 13 is transmitted to at least the voltage control unit 11, the deceleration fuel injection control unit 12, and the automatic stop prediction unit 14.

  The automatic stop control unit 15 automatically stops the engine when a predetermined engine stop condition is satisfied when the vehicle is stopped. In this embodiment, the brake switch 34 detects the vehicle braking operation by the brake device ( That the brake switch 34 is ON), the accelerator opening detected by the accelerator opening sensor 32 is fully closed, and the vehicle speed detected by the vehicle speed sensor 33 is zero (0: zero). An engine stop condition is set, and the engine is automatically stopped when this condition is satisfied. The engine automatic stop mechanism is the same as that conventionally known.

Furthermore, the automatic stop prediction unit 14 determines that the engine stop condition is based on the road environment information obtained by the navigation device 35 when the deceleration state detection unit 13 detects a predetermined deceleration state for the driving state of the vehicle. It is predicted whether or not it will be established.
Specifically, based on accident information, traffic regulation information or traffic jam information obtained by the navigation device 35, and road environment information such as the distance to the intersection in the traveling direction of the vehicle, the vehicle will soon stop and the engine will stop. It is predicted whether or not (that is, whether or not the engine automatic stop condition is satisfied). The prediction signal from the automatic stop prediction unit 14 is transmitted to at least the voltage control unit 11.

  In this case, the range to be predicted is, for example, a preset distance from the vehicle position, and it is predicted whether or not the engine automatic stop condition is satisfied within the predicted range. This prediction range is, for example, a region where road environments such as an urban area and a suburb are different from each other based on map information, and the prediction range is wider in a suburb than in an urban area, for example, according to the classification situation. You may make it change according to various conditions, such as setting.

When predicting the establishment of the engine automatic stop condition, other various road environment information can be used without being limited to the above road environment information as long as the prediction accuracy can be maintained or improved. .
For example, if the destination is clear in advance, whether to pass a railroad crossing, whether to make a right turn at an intersection, or if available, traffic light display information (red, blue, yellow ) And its switching timing are also useful information.

  In this embodiment, in a vehicle having an automatic engine stop function that automatically stops the engine when the engine stop condition is satisfied when the vehicle is stopped, the generator is controlled by voltage control to regenerate braking energy during vehicle braking. In this case, it is predicted that the engine stop condition is satisfied by the automatic stop prediction unit 14 so that the energy regeneration efficiency at the time of vehicle braking can be increased as much as possible without sacrificing the regeneration of braking energy as much as possible. The output voltage of the generator 20 is set to the Hi voltage until the engine is automatically stopped by the automatic stop control unit 15.

  That is, conventionally, as shown in FIG. 3, when the vehicle is decelerated, the output voltage of the generator 20 is controlled to the Hi voltage and the regeneration of the braking energy is promoted. As shown, when the vehicle speed decreases until the engine speed reaches the fuel return speed, regardless of whether the engine is idled or stopped, The output voltage of the generator 20 is controlled to the Lo voltage, and the regeneration of braking energy is suppressed even when the engine stop condition is satisfied and the engine is automatically stopped. That is, conventionally, even when the engine is automatically stopped when the engine stop condition is satisfied, regeneration of the braking energy is performed by an amount corresponding to the area Ed surrounded by the broken line and the broken line in FIG. It must be sacrificed, and the energy regeneration efficiency at the time of vehicle braking was lowered accordingly.

On the other hand, in this embodiment, when the automatic stop prediction unit 14 predicts that the engine stop condition is satisfied, the automatic stop control unit 15 does not stop the engine until the automatic stop of the engine 20 is performed. Since the output voltage is controlled to the Hi voltage, the energy regeneration efficiency during vehicle braking can be further increased without sacrificing the regeneration of braking energy as much as possible.
That is, in the present embodiment, when a predetermined deceleration state is detected with respect to the driving state of the vehicle, the navigation device 35 obtains the road environment information related to the road environment of the traveling path in the traveling direction of the own vehicle. Whether or not the engine stop condition is satisfied is predicted by the automatic stop prediction unit 14, and if it is predicted that the engine stop condition is satisfied, power generation is performed until the automatic stop control unit 15 performs automatic engine stop. The output voltage of the machine 20 is controlled to the Hi voltage.

  Therefore, when it is predicted that the engine stop condition is not satisfied, the output voltage control of the generator 20 is reliably performed according to the deceleration state of the vehicle, while the engine stop condition is predicted to be satisfied. Until the engine is automatically stopped by the automatic stop control unit 15, the output voltage of the generator 20 is controlled to the Hi voltage, so that regeneration of the braking energy is not sacrificed and the vehicle braking is not performed. A higher regeneration efficiency can be obtained for the regeneration of the braking energy. That is, in the diagram showing the power generation voltage in FIG. 3, the amount of power generation is increased by an amount corresponding to the area of the area Ed surrounded by the solid line and the broken line, and the regeneration efficiency of braking energy during vehicle braking is further increased. Can do it.

  When the automatic stop prediction unit 14 predicts that the engine stop condition is satisfied and the engine speed has decreased to the fuel return engine speed, the output voltage of the generator 20 is set to the Hi Instead of controlling the voltage, the voltage may be controlled to a third voltage (Mid voltage) lower than the Hi voltage and higher than the Lo voltage.

  Thereby, when the engine speed is reduced to the fuel return engine speed and the engine stall is more likely to occur, the output voltage of the generator 20 is controlled to a Mid voltage lower than the Hi voltage and higher than the Lo voltage. By reducing the output voltage of the generator 20 below the Hi voltage, the engine load can be reduced accordingly, the risk of engine stall can be more effectively suppressed, and the regeneration of braking energy during vehicle braking is constant. The effect of improving the regeneration efficiency can be ensured.

  In this case, in particular, it is preferable to continue the voltage control with the Mid voltage until the automatic stop control unit 15 automatically stops the engine. As a result, the risk of engine stall can be more effectively suppressed until the engine is automatically stopped, and a certain regeneration efficiency improvement effect is ensured for the regeneration of braking energy during vehicle braking, improving the fuel efficiency characteristics of the vehicle. Can contribute.

The operation of the vehicle engine control system configured as described above will be described with reference to the flowchart of FIG.
When the control starts, first, various detection signals and measurement signals are read in step S1. That is, the engine speed, the accelerator opening, the vehicle speed, the ON / OFF state of the brake switch 34 are read, and the road environment information related to the road environment of the traveling path in the traveling direction of the own vehicle is further read from the navigation device 35. The navigation information that is included is read.

  Next, in step S2, the automatic stop control unit 15 determines whether or not an engine automatic stop condition (the brake switch 34 is ON, the accelerator opening is fully closed, and the vehicle speed is zero) is satisfied. If the determination result is YES, in step S14, the fuel injection supply by the fuel injection valve 26 is stopped (so-called fuel cut) and the ignition operation of the spark plug 27 is also stopped (ignition cut), thereby causing the engine to rotate. Stops. Therefore, the power generation voltage of the generator 20 becomes zero (step S15).

On the other hand, if the determination result in step S2 is NO (the engine automatic stop condition is not satisfied), in step S3, the deceleration state detection unit 13 causes the vehicle operating state to be a predetermined deceleration based on the accelerator opening and the vehicle speed. It is determined whether or not it is a state. In this embodiment, if the vehicle speed is equal to or higher than a predetermined value and the accelerator opening is fully closed, it is determined that the vehicle is in a predetermined deceleration state. If the determination result is NO, the vehicle is not in a predetermined deceleration state, and thus the generated voltage (output voltage) of the generator 20 is controlled to the Lo voltage in step S4.
If the decision result in the step S3 is YES, that is, if the vehicle is in a predetermined deceleration state, the fuel cut (step S5) is executed and the output voltage of the generator 20 is controlled to the Hi voltage (step S6). ).

  Next, in step S7, it is determined whether the automatic stop prediction unit 14 has predicted an automatic stop of the engine. If this determination result is NO, that is, if an automatic engine stop is not predicted, it is further determined in step S8 whether or not the engine speed is equal to or lower than the fuel return speed, and if this determination result is YES Then, the output voltage of the generator 20 is controlled to the Lo voltage (step S9), the fuel cut is released, and the fuel injection supply is resumed (fuel return: step S10).

  On the other hand, if the determination result in step S7 is YES, that is, if an automatic engine stop is predicted, it is further determined in step S11 whether or not the engine speed is equal to or lower than the fuel return speed. When the determination result is YES, the output voltage of the generator 20 is controlled to the Hi voltage or the Mid voltage (step S12), the fuel cut is released, and the fuel injection supply is resumed (fuel return: step S13).

  Further, even when the vehicle is in a predetermined deceleration state (step S3: YES), when the engine speed is not reduced until it becomes equal to or lower than the fuel return speed, that is, when the determination result in step S8 is NO, If the determination result in step S11 is NO, the process returns to step S1 and the subsequent steps are repeatedly executed.

As described above, according to the present embodiment, basically, the Hi voltage that promotes charging of the output voltage of the generator 20 to the battery when a predetermined deceleration state is detected for the driving state of the vehicle. When the predetermined deceleration state is not detected, the output voltage of the generator 20 is controlled to the Lo voltage that suppresses the charging of the battery, thereby regenerating braking energy during vehicle braking, As a result, the fuel efficiency characteristics of the engine can be improved.
Further, when a predetermined deceleration state is detected with respect to the driving state of the vehicle, based on the road environment information related to the road environment of the traveling path in the traveling direction of the host vehicle obtained by the navigation device 35 equipped on the vehicle. If the engine stop condition is predicted and the engine stop condition is predicted to be satisfied, the output voltage of the generator 20 is set to the Hi voltage or the Mid voltage until the engine is automatically stopped. Be controlled.

  Therefore, when it is predicted that the engine stop condition is not satisfied, the output voltage control of the generator 20 is reliably performed according to the deceleration state of the vehicle, while the engine stop condition is predicted to be satisfied. Until the engine is automatically stopped, the output voltage of the generator 20 is controlled to the Hi voltage, so that the regeneration of the braking energy is not sacrificed. Higher regeneration efficiency can be obtained. Further, when the output voltage is controlled to be a Mid voltage lower than the Hi voltage and higher than the Lo voltage, the output voltage of the generator 20 is lowered below the Hi voltage to reduce the engine load accordingly, and engine stalling is generated. The risk can be more effectively suppressed, and a certain regeneration efficiency improvement effect can be secured for regeneration of braking energy during vehicle braking.

  It should be noted that the present invention is not limited to the above embodiment, and various modifications and variations can be made without departing from the scope of the present invention.

  The present invention relates to a control device for a vehicular generator that controls a dynamo that is driven by an engine and can supply power to an on-vehicle battery and a vehicular electrical load. In a vehicle having an engine automatic stop function for automatically stopping the engine, when the voltage control of the generator 20 is performed to regenerate the braking energy during vehicle braking, the regeneration of the braking energy is not sacrificed as much as possible. The energy regeneration efficiency during vehicle braking can be increased as much as possible, and can be effectively used as a control device for a generator for vehicles such as automobiles including passenger cars, buses, trucks, and the like.

1 is a block configuration diagram schematically showing a configuration of a vehicle engine control system according to an embodiment of the present invention. It is a flowchart explaining the action | operation of the said control system. It is explanatory drawing explaining the timing of the change to the deceleration state of the vehicle in the said embodiment, and the change of the generated voltage of a generator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Engine control unit 11 Voltage control part 12 Fuel injection control part at the time of deceleration 13 Deceleration state detection part 14 Automatic stop prediction part 15 Automatic stop control part 20 Generator 21 Battery 22 Electric load for vehicles 26 Fuel injection valve 27 Spark plug 31 Engine rotation Number sensor 32 Accelerator opening sensor 33 Vehicle speed sensor 34 Brake switch 35 Navigation device

Claims (3)

It has a navigation device that can obtain road environment information related to the road environment of the traveling path in the traveling direction of the host vehicle, and automatic stop control means that automatically stops the engine when the engine stop condition is satisfied when the vehicle stops A control device for a vehicle generator that controls a generator that is mounted on a vehicle and that is driven by the engine and can supply electric power to an on-vehicle battery and a vehicle electrical load,
Driving state detection means for detecting the driving state of the vehicle;
The output voltage of the generator is controllable to a first voltage that promotes charging of the battery and a second voltage that suppresses charging of the battery, and a predetermined deceleration state is detected for the driving state of the vehicle Voltage control means for controlling the output voltage of the generator to the first voltage in the case, and controlling the output voltage of the generator to the second voltage when the predetermined deceleration state is not detected;
Automatic stop prediction means for predicting whether or not the engine stop condition is satisfied based on the road environment information obtained by the navigation device when a predetermined deceleration state is detected for the driving state of the vehicle; With
If it is predicted by the automatic stop prediction means that the engine stop condition is established, the output voltage of the generator is controlled to the first voltage until the automatic stop of the engine is performed by the automatic stop control means.
A control device for a vehicle generator. When a predetermined deceleration state is detected for the driving state of the vehicle, the fuel supply to the engine is stopped, and when the engine speed decreases to a preset fuel return engine speed, the fuel to the engine A fuel supply control means at the time of deceleration for starting supply is provided in the vehicle,
When it is predicted that the engine stop condition is satisfied by the automatic stop prediction means, and the engine speed is reduced to the fuel return engine speed, the voltage control means is configured to change the output voltage of the generator. A third voltage lower than the first voltage and higher than the second voltage is controlled.
The vehicle generator control device according to claim 1. 3. The control device for a vehicular generator according to claim 2, wherein the voltage control with the third voltage is continued until the engine automatic stop by the automatic stop control means is performed.

Images