JP2012144138A - Engine control device of series hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve drivability while improving fuel consumption efficiency in an engine control device of a series hybrid vehicle that is provided with an engine, an electric generator, a battery, and a driving motor.SOLUTION: In the engine control device (11), there are provided: a vehicle speed detection means (13) that detects the vehicle speed; an accelerator operation amount detection means (14) that detects the amount of the accelerator operation; and a control means (12) that controls the engine speed based on the vehicle speed detected by the vehicle speed detection means (13) and the accelerator operation amount detected by the accelerator operation amount detection means (14).

Description

  The present invention relates to an engine control device for a series hybrid vehicle, and more particularly to an engine control device for a series hybrid vehicle in which wheels are driven by a drive motor and the engine is used only for power generation.

As shown in FIG. 9, a series hybrid vehicle 101 as a vehicle includes an engine 102, a generator 103 driven by the engine 102, a battery 104 charged by the generator 103, and power generated by the generator 103. Or the drive motor 105 which drives a wheel with the discharge electric power of the battery 104 is provided. The engine 102 and the generator 103 are in electrical communication via a first power line N1. The generator 103 and the battery 104 are electrically connected via the second power line N2. The drive motor 105 is connected to one end of the third power line N3, and the other end of the third power line N3 is connected to the second power line N2, thereby electrically communicating with the generator 103 and the battery 104.
In such a series hybrid vehicle, it is not always necessary to start the engine and control the engine speed according to the depressed state of the accelerator pedal as in a typical ordinary gasoline vehicle, and the engine is used only for power generation. Therefore, it is not used for the direct driving force of the wheel, and the wheel is driven only by the driving motor.
In series hybrid vehicles, it is possible to consider only the operation (control) with good fuel efficiency, and the control when considering only the fuel efficiency is started at the engine speed and torque with the best efficiency of the engine. Is effective (reducing the number of startings as much as possible by fixed point operation). On the other hand, controlling the engine speed in conjunction with the accelerator operation, as in a gasoline vehicle, and performing idle stop and frequently starting and stopping the engine are disadvantageous in terms of fuel efficiency. It is.

As shown in FIG. 10, in a normal gasoline vehicle, the engine maintains a predetermined engine speed during idling of the engine, and the engine sound becomes the engine volume when idling at a low speed (idle stop). In the case of a vehicle, stop.)
The accelerator pedal is depressed from the idling state, and the accelerator opening is determined by the accelerator operation amount when the accelerator pedal is depressed, and the engine torque and the engine speed are output. When the accelerator pedal is depressed, fuel is injected into the engine, and engine noise is generated due to the explosion of the engine. This engine sound increases as the engine speed increases.
When the accelerator pedal is returned, the fuel injection to the engine is stopped. However, if the vehicle speed is high, the engine continues to drive, and the engine volume decreases in the engine brake state.
More specifically, in the relationship among the vehicle speed, the engine speed, and the engine volume in FIG. 10, the accelerator pedal is depressed at the time of acceleration during idling of the engine mounted on a normal gasoline vehicle (time t0). When the accelerator operation amount increases (time t1), the vehicle speed, the engine speed, and the engine volume all increase. Thereafter, when the accelerator pedal is returned to zero (0) (time t2), Since the engine volume changes depending on the presence or absence of fuel injection, it differs from the engine speed and is considerably lower than the engine speed.
When the accelerator operation amount becomes zero (0) (time t2) and time T elapses, and the accelerator pedal is depressed and the accelerator operation amount increases (time t3) during acceleration, the vehicle speed and the engine When both the engine speed and the engine volume increase and the accelerator pedal is returned to zero (0) (time t4), the fuel injection to the engine stops and the engine volume decreases rapidly. It gradually decreases in proportion to the engine speed.
Further, in the concept of the relationship between the vehicle speed, the engine speed, and the engine volume in FIG. 11, when the accelerator pedal is depressed and the accelerator operation amount increases during acceleration (time t1), the vehicle speed, the engine speed, and the engine volume. When the accelerator pedal is returned and the accelerator operation amount becomes zero (0) (time t2), the vehicle speed and the engine speed increase as they are, but the engine volume is determined by whether fuel is injected or not. Therefore, unlike the engine speed, it is considerably lower than the engine speed. Then, the vehicle speed and the engine speed decrease after reaching predetermined values (time t3).
When the accelerator operation amount becomes zero (0) (time t2) and a certain time T elapses and the acceleration pedal is depressed and the accelerator operation amount increases (time t4) at the time of acceleration again, the vehicle speed and the engine When both the engine speed and the engine volume increase and the accelerator pedal is returned to zero (0) (time t5), the engine is stopped, and the engine volume decreases once and then gradually decreases. The vehicle speed and the engine speed increase as they are, and thereafter reach a predetermined value (time t6), and then decrease in proportion.

Next, as shown in FIG. 12, in the control of a normal series hybrid vehicle, when the battery storage amount (SOC) is high, the drive motor is rotated only by the power of the battery without generating power by the engine.
In the control of this normal series hybrid vehicle, the engine is stopped when the accelerator pedal is not depressed. When the battery charge (SOC) is lowered to a certain level, when the accelerator pedal is depressed and driving force is required, the engine is started and power is generated. When the accelerator pedal is depressed, the engine speed is increased by the amount of accelerator operation corresponding to the depression of the accelerator pedal because the accelerator is linked.
Return the accelerator pedal to zero (0), and stop the engine. When the accelerator pedal is depressed again while the vehicle speed is at a predetermined value, the engine starts again, and the engine is driven by the amount of accelerator operation corresponding to the depression of the accelerator pedal. When the battery storage amount (SOC) becomes too low, power generation by the engine is maintained even when the vehicle is stopped.
More specifically, in the relationship between the vehicle speed, the engine speed, and the engine volume of the normal series hybrid vehicle in FIG. 12, when the accelerator pedal is depressed and the accelerator operation amount increases during acceleration (time t1). ) First, the vehicle speed starts increasing, then the engine is started (time t2), both the engine speed and the engine volume increase, and the accelerator pedal is returned to zero (0). Then (time t3), the engine is stopped to save fuel, and at this time, the engine speed and the engine volume are rapidly reduced to substantially zero (0).
When time T elapses from when the accelerator operation amount becomes zero (0) (time t3) and the accelerator pedal is depressed and the accelerator operation amount increases during acceleration, the engine is restarted (time t4). ) When the vehicle speed, the engine speed and the engine volume increase in proportion, and then the accelerator pedal is returned to zero (0) (time t5), the engine is stopped and the engine speed and the engine volume are reduced. Although the vehicle speed decreases rapidly, the vehicle speed gradually decreases.
Further, in the concept of the relationship between the vehicle speed, the engine speed, and the engine volume of the normal series hybrid vehicle in FIG. 13, when the accelerator pedal is depressed and the accelerator operation amount increases during acceleration (time t1), When the vehicle speed, the engine speed, and the engine volume all increase (time t2) and then the accelerator pedal is returned and the accelerator operation amount becomes zero (0), the engine is stopped (time t2). It decreases to zero (0), and the engine speed is close to zero (0), but the vehicle speed reaches a predetermined value (time t3), and then begins to decrease.
When time T elapses from when the accelerator operation amount becomes zero (0) (time t2) and the accelerator pedal is depressed and the accelerator operation amount increases during acceleration, the engine is restarted (time t4). ) When the engine volume starts to increase and the vehicle speed and the engine speed increase, and then the accelerator pedal is returned to zero (0) (time t5), the engine is stopped and the engine volume and the engine speed are increased. The vehicle speed decreases to a predetermined value (time t6), and then gradually decreases.

However, efficient power generation by fixed point operation is disadvantageous when drivability is considered. Because the driver is accustomed to the reaction of the usual gasoline car so far, if the accelerator pedal is depressed, the engine speed will increase, and if the accelerator pedal is returned, the engine speed will decrease. Despite the fact that the accelerator pedal is depressed a little against the driver's intention in the control for enhancing the power generation effect, the high engine speed is maintained, and the engine is started and stopped regardless of the vehicle speed. And give a sense of incongruity.
In order to take into account the above drivability, accelerator-linked control is generally used to start the engine and generate power when the driver depresses the accelerator pedal and needs power (torque and rotation speed). ing.
In addition, when the accelerator pedal is returned and the vehicle stops, an idling stop control for stopping the engine is also incorporated. However, when the battery storage amount (SOC) does not satisfy a certain value, the engine is started to generate power regardless of the vehicle speed and the accelerator operation amount.

Japanese Patent Laid-Open No. 9-154205 JP 2001-103606 A JP-A-8-256403

The hybrid vehicle according to Patent Document 1 feeds back the engine speed and torque signal, stops the engine in a preferable state according to the vehicle running state and driving state, or starts the engine only in a necessary state. is there.
The series hybrid electric vehicle according to Patent Literature 2 controls the charging device according to the state of the battery temperature, thereby reducing engine noise or the like during stoppage or low-speed traveling.
The power generation control method and apparatus in a series hybrid vehicle according to Patent Document 3 limits the upper limit of the target value of the engine speed based on the maximum engine speed, and changes the maximum engine speed according to the speed of the drive motor. Is.

However, conventionally, in the series hybrid vehicle, the power generation efficiency and drivability (driving comfort of the driver) have not been well harmonized by the way the engine is started.
For example, when the power generation efficiency of the engine is given priority, it is recommended that the engine be operated at one point where the engine is most efficient and that the engine be stopped as much as possible.
However, in this case, the driver does not make an engine sound corresponding to the depressed state of the accelerator pedal as in a normal gasoline vehicle, which makes the driver uncomfortable and uncomfortable.
Next, considering drivability as a priority, as with conventional gasoline vehicles, the engine speed and torque are controlled in accordance with the accelerator pedal depression, so that drivability is equivalent to that of ordinary gasoline vehicles. can do.
However, in this case, the goodness of the series hybrid vehicle that can separately drive and generate power is lost, and the power generation efficiency of the engine is poor and the fuel consumption is also reduced.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an engine control device for a series hybrid vehicle that can achieve both fuel efficiency and improved drivability.

  The present invention is a series comprising an engine, a generator driven by the engine, a battery charged by the generator, and a drive motor for driving a wheel by the generated power of the generator or the discharged power of the battery. In the hybrid vehicle engine control device, a vehicle speed detecting means for detecting the vehicle speed is provided, an accelerator operation amount detecting means for detecting the accelerator operation amount is provided, and the vehicle speed detected by the vehicle speed detecting means and the accelerator operation amount detecting means are detected. The control means for controlling the engine speed based on the accelerator operation amount is provided.

  The engine control apparatus for a series hybrid vehicle according to the present invention can improve fuel efficiency and drivability.

FIG. 1 is a system configuration diagram of an engine control apparatus. (Example) FIG. 2 is a flowchart of engine control. (Example) FIG. 3 is a flowchart for setting various modes. (Example) FIG. 4 is a flowchart of the forced engine power generation mode. (Example) FIG. 5 is a flowchart of the vehicle speed interlocking engine control mode. (Example) FIG. 6 is a flowchart of the electric vehicle (EV) mode. (Example) FIG. 7 is a diagram showing the relationship among vehicle speed, engine speed, and engine volume in vehicle speed-linked engine control. (Example) FIG. 8 is a conceptual diagram showing the relationship among vehicle speed, engine speed, and engine volume in vehicle speed-linked engine control. (Example) FIG. 9 is a conventional system configuration diagram of an engine control apparatus. (Conventional example) FIG. 10 is a diagram showing the relationship among the vehicle speed, engine speed, and engine volume of a conventional gasoline vehicle. (Conventional example) FIG. 11 is a conceptual diagram showing the relationship among the vehicle speed, engine speed, and engine volume of a conventional gasoline vehicle. (Conventional example) FIG. 12 is a diagram showing the relationship among the vehicle speed, engine speed, and engine volume of conventional series hybrid control (accelerator-linked type). (Conventional example) FIG. 13 is a conceptual diagram showing the relationship among vehicle speed, engine speed, and engine volume in conventional series hybrid control (accelerator-linked type). (Conventional example)

  This invention achieves the objective of achieving both fuel efficiency and improved drivability by increasing the engine speed according to the depressed state of the accelerator pedal and lowering the engine speed by returning the accelerator pedal. is there.

1 to 8 show an embodiment of the present invention.
In FIG. 1, 1 is a series hybrid vehicle (hereinafter referred to as “vehicle”), 2L is a left front wheel, 2R is a right front wheel, 3 is a front axle, 4L is a left rear wheel, 4R is a right rear wheel, and 5 is a rear axle. .
The vehicle 1 includes an engine 6, a generator 7 driven by the engine 6, a battery 8 charged by the generator 7, and a left front wheel as a wheel by the generated power of the generator 7 or the discharged power of the battery 8. 2L and a drive motor 9 for driving the right front wheel 2R. A fuel injection valve 10 is attached to the engine 6. The drive motor 9 outputs a driving force to the front axle 3 to drive the left front wheel 2L and the right front wheel 2R.
The engine 6 and the generator 7 are in electrical communication with each other through the first power line M1. The generator 7 and the battery 8 are electrically connected by a second power line M2. The battery 8 and the drive motor 9 are electrically connected by a third power line M3.
Control means 12 constituting an engine control device 11 is in communication with the fuel injection valve 10, the generator 7, and the drive motor 9 of the engine 6.
The control means 12 detects a vehicle speed detection means 13 for detecting the vehicle speed, an accelerator operation amount detection means 14 for detecting an accelerator operation amount as an accelerator pedal depression amount, and a brake operation amount as a brake pedal depression amount. The brake operation amount detecting means 15, the engine speed detecting means 16 for detecting the engine speed, the battery charge amount detecting means 17, the drive motor speed detecting means 18, and the ignition switch (IG / SW) 19 are connected. is doing.

The control means 12 controls the engine speed based on the vehicle speed detected by the vehicle speed detection means 13 and the accelerator operation amount detected by the accelerator operation amount detection means 14.
The control means 12 decreases the engine speed when the accelerator operation amount detection means 14 detects that the accelerator operation amount is zero (0).
The control means 12 is in a state where the accelerator operation amount is detected as zero (0) by the accelerator operation amount detection means 14, and the brake operation amount is detected as zero (0) by the 15th step of the brake operation amount detector. The engine 6 is stopped when continuing for a preset fixed time.
The control means 12 is a state where the accelerator operation amount is detected as zero (0) by the accelerator operation amount detection means 14 and a state equal to or lower than the first vehicle speed preset by the vehicle speed detection means 13 is preset. When the time continues, the engine 6 is stopped. In this case, when the state where the accelerator operation amount is detected as zero (0) and the state where the brake operation amount is detected at a predetermined speed below the preset first vehicle speed continues for a predetermined period of time, It is also possible to stop the engine 6. Here, the “preset first vehicle speed” is a vehicle speed at which the vehicle 1 is predicted to stop, and may be, for example, 5 km / h, but is set to a vehicle speed higher than that value. May be.
When the accelerator operation amount is detected by the accelerator operation amount detection unit 14 and the vehicle speed detected by the vehicle speed detection unit 13 is equal to or higher than a preset second vehicle speed, the control unit 12 Start. The “preset second vehicle speed” can be set regardless of the above “preset first vehicle speed”.
The control means 12 is configured such that the battery storage amount (SOC: battery remaining amount) of the battery 8 is not less than the preset first accumulation amount (20%) and not more than the preset second accumulation amount (50%). At some time, that is, in the vehicle speed interlocking engine control mode, the engine speed is controlled.
The control means 12 drives the engine 6 when the battery storage amount (SOC) of the battery 8 is smaller than the preset first storage amount (20%), that is, in the forced engine power generation mode, and the accelerator operation amount. When the accelerator operation amount detected by the detection means 14 is larger than a preset set operation amount, based on the vehicle speed detected by the vehicle speed detection means 13 and the accelerator operation amount detected by the accelerator operation amount detection means 14. Controls engine speed.
The control means 12 also decreases the engine speed when the accelerator operation amount detecting means 14 detects that the accelerator operation amount is zero (0) even in the forced engine power generation mode.

Next, engine control according to this embodiment will be described based on the flowchart of FIG.
As shown in FIG. 2, when the program of the control means 12 is started (step A01), first, the engine 6 is stopped (step A02), the accelerator pedal is depressed, the accelerator operation amount increases, and the vehicle speed exceeds the predetermined value. It is determined whether or not it has been raised (step A03). If step A03 is NO, this determination is continued.
If this step A03 is YES, the engine 6 is started, the engine speed is set higher than the motor speed of the drive motor 9, and the power generation by the engine 6 is strengthened (step A04).
Then, it is determined whether or not the accelerator pedal returns and the accelerator operation amount becomes zero (0) (step A05). If step A05 is NO, the process returns to step A04.
If this step A05 is YES, the engine 6 is restarted, the engine speed is set lower than the motor speed of the drive motor 9, and the power generation by the engine 6 is weakened (step A06).
Thereafter, it is determined whether or not the vehicle speed has become low (step A07). If step A07 is NO, the process returns to step A03.
On the other hand, if step A07 is YES, the process returns to step A02.

Next, control for switching each mode in accordance with the battery storage amount (SOC) will be described based on the flowchart of FIG.
As shown in FIG. 3, when the program of the control means 12 is started (step B01), the battery storage amount (SOC) is either SOC <20%, 20% ≦ SOC ≦ 50%, or SOC> 50%. Is determined (step B02).
If SOC <20% in step B02, the forced engine power generation mode is set (step B03).
If 20% ≦ SOC ≦ 50% in step B02, the vehicle speed interlocking engine control mode is set (step B04).
If SOC> 50% in step B02, the electric vehicle (EV) mode is set (step B05).
Then, after processing in the forced engine power generation mode in step B03 or processing in the vehicle speed interlocking engine control mode in step B04, it is determined whether or not the ignition switch 19 is off (step B06). .
When this step B06 is NO, it returns to said step B02.
On the other hand, if this step B06 is YES, or after processing in the electric vehicle (EV) mode in step B05, the program is ended (step B07).

The processing in the forced engine power generation mode in step B03 is performed based on the flowchart of FIG.
In this forced engine power generation mode, the battery storage amount (SOC) is low, and power generation by the engine 6 is forcibly required, and the control is the same as in a normal series hybrid vehicle, and the battery storage amount (SOC) is maintained at a constant level. Control is performed as follows. Even when the vehicle is stopped, the engine 6 is not stopped. If the battery storage amount (SOC) exceeds a set storage amount (threshold), the vehicle speed-linked engine control mode is controlled.
As shown in FIG. 4, when the forced engine power generation mode program is started in the control means 12 (step C01), power is generated by the engine 6 at a constant engine speed even when the vehicle is stopped (step C02), and the accelerator pedal is depressed a little. It is then determined whether or not the accelerator operation amount has become larger than a predetermined value (step C03). If step C03 is NO, the process returns to step C02.
If this step C03 is YES, as in the vehicle speed interlocking engine control mode, power is generated by the engine 6 (step C04), and the program is ended (step C05).

The processing in the vehicle speed interlocking engine control mode in step B04 is performed based on the flowchart of FIG.
In this vehicle speed interlocking engine control mode, when the battery charge (SOC) is lowered to a certain level and the accelerator pedal is depressed, the engine speed is set higher than the engine speed of a normal gasoline vehicle, Furthermore, the amount of increase in the engine speed is larger than that of a normal gasoline vehicle. Even if the accelerator operation amount detected by the accelerator operation amount detection means 14 becomes zero (0), the engine 6 is not immediately stopped. The engine 6 continues to drive at a lower speed than that of a normal gasoline vehicle. By doing so, the loss due to the start / stop of the engine 6 due to a minute time is minimized. This makes the driver feel the change by using the increase / decrease in engine sound and improves drivability. In a normal gasoline vehicle, even if the accelerator operation amount becomes zero (0), the engine 6 continues to operate and enters an engine brake state, which is simulated. The accelerator pedal returns completely, and the engine 6 is stopped after seeing the brake state for a certain time and below a predetermined vehicle speed.
As shown in FIG. 5, when the vehicle speed-linked engine control mode program is started in the control means 12 (step D01), it is determined whether or not the accelerator operation amount is equal to or greater than a set value (step D02).
If this step D02 is YES, the acceleration mode is set, and the engine speed is determined based on the accelerator opening and the vehicle speed (step D03). In this case, the engine speed is increased so as to approach the engine speed at which the engine 6 is efficient as much as possible.
On the other hand, if this step D02 is NO, it is determined whether or not the brake operation amount is not less than the set value (step D04).
If this step D04 is YES, the brake regeneration and stop modes are set, and the engine 6 is stopped by the brake state for a certain period and the stop of the vehicle 1 (step D05).
On the other hand, if this step D04 is NO, the coast regeneration mode is set, and the engine speed is lowered below the engine speed in the acceleration mode and equal to or less than the engine speed of a normal gasoline vehicle (step D06). .
After the process of step D03, after the process of step D05, or after the process of step D06, the program is ended (step D07).

The electric vehicle (EV) mode process in step B05 is performed based on the flowchart of FIG.
In this electric vehicle (EV) mode, since the battery storage amount (SOC) is high, power generation by the engine 6 is not performed as usual, and the left front wheel 2L and the right front wheel 2R are driven by electric power of only the battery 8. However, when it is determined that the vehicle is a highway, the engine 6 is started, and the battery 8 is predicted to decrease first, and power generation by the engine 6 is started. At this time, the engine 6 is controlled with priority given to maintaining the battery storage amount (SOC) so that the battery storage amount (SOC) does not become excessively high.
As shown in FIG. 6, when the program of the electric vehicle (EV) mode is started in the control means 12 (step E01), it is determined whether or not the road is an expressway (step E02).
If this step E02 is YES, it is determined whether or not the battery storage amount (SOC) is equal to or greater than a set value (for example, 99.5%) (step E03).
When this step E03 is YES or when the step E02 is NO, the engine 6 does not generate electricity and travels only as an electric vehicle (EV) (step E04).
On the other hand, if this step E03 is NO, the highway mode is set, and power generation is performed at the most efficient engine speed according to the vehicle speed, or at an engine speed equal to or higher than that of a normal gasoline vehicle. To maintain the current battery charge (SOC) (step E05).
After the process of step E04 or after the process of step E05, the program is ended (step E06).

That is, in the engine control according to this embodiment, the forced engine power generation mode when the battery storage amount (SOC) is low, the electric vehicle (EV) mode when the battery storage amount (SOC) is high, and an intermediate between these modes. Three modes, a vehicle speed interlocking engine control mode, are set, and the power generation method of the engine 6 is changed in each mode.
In particular, the vehicle speed-linked engine control mode is a vehicle linkage-linked type that improves drivability due to the uncomfortable feeling of the engine speed by linking the power generation of the engine 6 to the vehicle speed. In a normal gasoline vehicle, the range of the engine speed changes with respect to the vehicle speed at the gear position. However, since the vehicle speed and the engine speed are basically proportional, the engine speed increases as the vehicle speed increases. Therefore, when the vehicle speed is high, drivability does not deteriorate even when the engine 6 is started.
When accelerating a normal gasoline car, the explosion sound is increased by injecting gasoline as fuel, and if the accelerator operation amount is reduced, the explosion sound is lost even if the engine speed does not change. Become.
Therefore, in this embodiment, when the accelerator pedal is depressed, the engine 6 is driven higher in accordance with the vehicle speed to generate electric power, and when the accelerator pedal returns, the electric power is generated slightly weakly in accordance with the vehicle speed. By controlling the engine 6 with gradual speed, drivability can be improved.
As a result, the fuel consumption is close to a fixed point driving, and the drivability can be driven like a normal gasoline car.

Next, the relationship among the vehicle speed, engine speed, and engine volume in the vehicle speed interlocking engine control according to this embodiment will be described based on the time chart of FIG.
In the relationship between the vehicle speed, the engine speed, and the engine volume in the vehicle speed interlocking control, when the battery storage amount (SOC) is high, the drive motor 9 is rotated only by the power of the battery 8 without generating power by the engine 6. The vehicle 1 travels. However, if it is recognized that the vehicle is traveling at high speed, power is generated by the engine 6, and otherwise the engine 6 is stopped.
Then, when the battery storage amount (SOC) is lowered to a certain level, power generation by the engine 6 is started in conjunction with the vehicle speed. The operation speed of the engine 6 is set higher than that of a normal gasoline vehicle. Further, the increase in the engine speed when further accelerating is made larger than that in the case of a normal gasoline vehicle.
Further, when the accelerator operation amount becomes zero (0), the engine speed lower than the motor speed of the normal drive motor 9 is maintained. The drivability is maintained by the difference in rotation speed. When the accelerator operation amount increases again, if the engine 6 is stopped, the engine 6 is started, and similarly, the engine speed is set higher than the amount of depression of the accelerator pedal and output.
Further, the engine 6 is stopped when the accelerator operation amount is zero (0), the brake operation amount is equal to or greater than the set value, and a fixed time has elapsed.
When the remaining battery level (SOC) becomes too low, power generation by the engine 6 is maintained even when the vehicle is stopped. Power generation by the engine 6 is performed until the value of the set battery storage amount (SOC) is reached. When the accelerator operation amount is large, the engine 6 generates a larger amount of power with vehicle speed interlocking engine control.
Specifically, in the relationship among the vehicle speed, the engine speed, and the engine volume in the vehicle speed interlocking control in FIG. 7, when the accelerator pedal is depressed and the accelerator operation amount increases during acceleration (time t1), first, The vehicle speed increases, and the engine 6 is started (time t2), and both the engine speed and the engine volume increase. In this case, the engine speed is set higher than in the prior art in accordance with the vehicle speed. Thereby, the electric power generation by the engine 6 can be increased.
Thereafter, when the accelerator pedal is returned and the accelerator operation amount becomes zero (0) (time t3), the time T from the time (time t3) to when the accelerator pedal is depressed again to increase the accelerator operation amount (time t4). Since the vehicle is linked to the vehicle speed, even if the amount of accelerator operation is zero (0), power is generated by the engine 6 in response to the vehicle speed. As a result, power generation can be weakened to improve drivability and engine efficiency.
Then, when the accelerator pedal is depressed and the accelerator operation amount starts to increase during time of acceleration again (time t4), all of the vehicle speed, the engine speed, and the engine volume increase. In this case, the engine speed is set higher than in the prior art in accordance with the vehicle speed. Thereby, the electric power generation by the engine 6 can be increased.
Thereafter, when the brake pedal is depressed and the brake amount becomes equal to or greater than the set value (time t5), the vehicle speed gradually decreases. However, the engine speed and the engine volume are not proportional to the vehicle speed and rapidly decrease.
Thereafter, the engine 6 is stopped when a certain time S has elapsed (time t6) from when the brake pedal is depressed (time t5).
Further, in the concept of the relationship between the vehicle speed, the engine speed, and the engine volume in the vehicle speed interlocking control in FIG. 8, when the accelerator pedal is depressed and the accelerator operation amount increases during acceleration (time t1), the vehicle speed and the engine are increased. When both the rotational speed and the engine volume increase, and then the accelerator pedal is returned and the accelerator operation amount becomes zero (0) (time t2), the engine volume decreases, and then the engine speed begins to decrease ( Time t3). Further, the engine speed becomes a predetermined value (time t4), and thereafter starts to decrease.
Then, when the accelerator operation amount becomes zero (0) (time t2) and time T elapses and the accelerator pedal is depressed (time t5) at the time of acceleration again, the engine speed, the engine volume, Starts to increase, then the vehicle speed also increases, and when the accelerator operation amount becomes zero (0) (time t6), when the engine load is high, power is generated by the engine 6, and when the engine load is low, the engine is lowered. 6 to generate power. Then, the vehicle speed becomes a predetermined value (time t7), and then decreases substantially in proportion to the engine speed and the engine volume.

Although the embodiments of the present invention have been described above, the configuration of the above-described embodiments will be described for each claim.
In the first aspect of the invention, the control means 12 controls the engine speed based on the vehicle speed detected by the vehicle speed detection means 13 and the accelerator operation amount detected by the accelerator operation amount detection means 14.
Thereby, fuel consumption can be improved without deteriorating drivability.
In the invention according to claim 2, when the accelerator operation amount detecting unit 14 detects that the accelerator operation amount is zero, the control unit 12 decreases the engine speed.
Thereby, the efficiency deterioration by the stop and restart of the engine 6 can be prevented. In addition, since the engine brake of a normal gasoline vehicle is applied in a pseudo manner, the driver can travel like a gasoline vehicle. In the invention according to claim 3, the control means 12 includes a brake operation. The brake operation amount detection means 15 for detecting the amount is in contact, the accelerator operation amount detection means 14 detects that the accelerator operation amount is zero, and the brake operation amount detection means 15 detects that the brake operation amount is zero. The engine 6 is stopped when the state continues for a predetermined time.
As a result, when the vehicle 1 is accurately predicted to stop and the vehicle 1 is predicted to continue running, the engine 6 is not stopped, so that deterioration in efficiency due to the stop and restart of the engine 6 can be prevented. On the other hand, when the vehicle 1 is predicted to stop, the engine 6 can be stopped to save fuel.
In the invention according to claim 4, the control means 12 is in a state where the accelerator operation amount is detected as zero by the accelerator operation amount detection means 14, and the state below the first vehicle speed preset by the vehicle speed detection means 13. The engine 6 is stopped when continuing for a preset fixed time.
As a result, when the vehicle 1 is accurately predicted to stop and the vehicle 1 is predicted to continue running, the engine 6 is not stopped, so that deterioration in efficiency due to the stop and restart of the engine 6 can be prevented. On the other hand, when the vehicle 1 is predicted to stop, the engine 6 can be stopped to save fuel.
In the invention according to claim 5, the control means 12 is a second state in which the accelerator operation amount is detected by the accelerator operation amount detection means 14 and the vehicle speed detected by the vehicle speed detection means 13 is preset. When the vehicle speed is higher than the vehicle speed, the engine 6 is started.
As a result, when the vehicle 1 is predicted to continue traveling with high accuracy and the vehicle 1 is predicted to continue traveling, the engine 6 is started, so that deterioration in efficiency due to the stop and restart of the engine 6 can be prevented. . On the other hand, when the vehicle 1 is predicted to stop, the engine 6 can be kept stopped to save fuel.
In the invention according to claim 6, the control means 12 is configured such that when the battery storage amount (SOC) of the battery 8 is equal to or greater than the preset first accumulation amount and equal to or less than the preset second accumulation amount. Control the number of revolutions.
Thereby, when there is much battery charge amount (SOC), since it is not necessary to charge the battery 8, the engine 6 can be stopped. On the other hand, when the battery storage amount (SOC) is small, the engine 6 can be rotated because it is necessary to charge the battery regardless of the traveling state.
In the invention according to claim 7, the control means 12 drives the engine 6 when the battery storage amount (SOC) of the battery 8 is smaller than the preset first storage amount, and the accelerator operation amount detection means 14 When the detected accelerator operation amount is larger than the preset set operation amount, the engine speed is determined based on the vehicle speed detected by the vehicle speed detection means 13 and the accelerator operation amount detected by the accelerator operation amount detection means 14. Control.
Thereby, when the battery charge amount (SOC) is small, the charge amount of the battery 8 can be increased without deteriorating drivability.
In the invention according to claim 8, in relation to the invention according to claim 7, the control means 12 reduces the engine speed when the accelerator operation amount detecting means 14 detects that the accelerator operation amount is zero.
As a result, the engine brake of a normal gasoline vehicle is applied in a pseudo manner, so that the driver can travel like a normal gasoline vehicle.

  The engine control device according to the present invention can be applied to various vehicles.

DESCRIPTION OF SYMBOLS 1 Vehicle 6 Engine 7 Generator 8 Battery 9 Drive motor 10 Fuel injection valve 11 Engine control device 12 Control means 13 Vehicle speed detection means 14 Accelerator operation amount detection means 15 Brake operation amount detection means 16 Engine rotation speed detection means 17 Battery charge amount detection Means 18 Drive motor rotational speed detection means 19 Ignition switch

Claims (8)

  Engine of a series hybrid vehicle comprising an engine, a generator driven by the engine, a battery charged by the generator, and a drive motor for driving wheels by the generated power of the generator or the discharged power of the battery In the control device, a vehicle speed detection means for detecting the vehicle speed is provided, an accelerator operation amount detection means for detecting the accelerator operation amount is provided, and the vehicle speed detected by the vehicle speed detection means and the accelerator operation detected by the accelerator operation amount detection means An engine control device for a series hybrid vehicle, characterized in that control means for controlling the engine speed based on the amount is provided.   2. The engine control device for a series hybrid vehicle according to claim 1, wherein the control means reduces the engine speed when the accelerator operation amount is detected as zero by the accelerator operation amount detection means.   The control means communicates with a brake operation amount detection means for detecting a brake operation amount, and the accelerator operation amount is detected as zero by the accelerator operation amount detection means, and the brake operation amount is detected by the brake operation amount detection means. 3. The engine control device for a series hybrid vehicle according to claim 1, wherein the engine is stopped when a state in which zero is detected continues for a predetermined period of time.   The control means is in a state where the accelerator operation amount is detected as zero by the accelerator operation amount detection means, and a state equal to or lower than the first vehicle speed preset by the vehicle speed detection means continues for a predetermined time. The engine control device for a series hybrid vehicle according to any one of claims 1 to 3, wherein the engine is sometimes stopped.   When the accelerator operation amount is detected by the accelerator operation amount detection unit and the vehicle speed detected by the vehicle speed detection unit is equal to or higher than a second vehicle speed set in advance, the control unit The engine control device for a series hybrid vehicle according to any one of claims 1 to 4, wherein the engine control device is started.   The control means executes control of the engine speed when the storage amount of the battery is not less than a preset first storage amount and not more than a preset second storage amount. The engine control apparatus of the series hybrid vehicle of any one of Claims 1-5.   The control means drives the engine when the storage amount of the battery is smaller than a preset first storage amount, and the accelerator operation amount detected by the accelerator operation amount detection means is set in advance. 2. The engine speed is controlled based on a vehicle speed detected by the vehicle speed detection unit and an accelerator operation amount detected by the accelerator operation amount detection unit when the operation amount is larger than the operation amount. Engine control system for series hybrid vehicles.   8. The engine control device for a series hybrid vehicle according to claim 7, wherein the control means reduces the engine speed when the accelerator operation amount is detected as zero by the accelerator operation amount detection means.

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