JPH10174208A - Hybrid electric vehicle - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve fuel efficiency and suppress generation of exhaust gas and noise in a hybrid electric vehicle. A generator (16) driven by an engine (17), a battery (15) charged by power supply from the generator, a traveling motor (11) driven by power supply from the generator (16), and a driver Operates the shift position sensor 22 for selecting the shift range of the vehicle, the charge capacity sensor 19 for detecting the state of charge of the battery 15, and the engine 17 when the charge capacity of the battery falls below a predetermined level. Controller 18
The controller 18 stops the engine 17 regardless of the charge capacity of the battery when the shift range of the vehicle is at the stop position (P, N).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid electric vehicle in which a motor is driven by selectively using electric power stored in a battery and electric power generated by a generator, and wheels are driven and rotated by the electric motor to travel. About.

[0002]

2. Description of the Related Art In recent years, there has been a demand for the practical use of, for example, a hybrid electric vehicle which suppresses the generation of exhaust gas due to the problem of the global environment. Application to trucks is desired. This hybrid electric vehicle has a motor and a generator,
A battery, an electric motor, etc. are installed, and the electric power stored in the battery or the electric power generated by the generator when the prime mover is driven is selectively used, and the electric motor is driven by this electric power, and the electric motor is driven. The vehicle is driven by rotating drive wheels that are drivingly connected to the output shaft.

That is, electric power required for traveling is stored in a battery in advance, and in traveling using this battery, electric power of the battery is supplied to a traveling motor under the control of a motor controller, and the traveling motor is operated. The driving wheels rotate by the rotational driving, and the electric vehicle can run. And when the power stored in the battery decreases,
By driving the engine and controlling the generator controller to operate the generator, the electric power generated by the generator is stored in the battery while the motor controller controls and supplies it to the traveling motor. Is driven to rotate, the drive wheels rotate, and the electric vehicle can run.

[0004] As described above, in the hybrid electric vehicle, the driving / stopping of the engine is controlled in accordance with the storage capacity of the battery, and the power stored in the battery and the power generated by the generator are selectively used. A motor is driven, and driving wheels are rotated by the motor to drive the vehicle.

[0005]

By the way, in such a hybrid electric vehicle, when the power of the battery is reduced, as described above, the engine is driven to operate the generator, so that the generator can generate power. The traveling power is supplied to the traveling motor while the stored electric power is stored in the battery. In this case, the engine is running at a predetermined speed while the vehicle is running, and idling at a low speed while the vehicle is stopped.

By the way, when driving the engine,
This is because the power of the battery is reduced and charging is required. However, when the engine is idling at a low rotation speed, charging is hardly performed. Therefore, when the engine is idling at a low rotation speed while the vehicle is stopped, there is a problem that fuel efficiency deteriorates. In addition, if the engine is idling while the vehicle is stopped, exhaust gas and engine noise are generated around the vehicle, which is environmentally unfavorable.

[0007] Such a hybrid electric vehicle is disclosed, for example, in JP-A-6-245324. The “control device for an engine-driven generator for an electric vehicle” disclosed in this publication drives the engine-driven generator when the accelerator opening is equal to or less than a predetermined value and the battery voltage is equal to or less than a predetermined value. It is designed to be charged.

However, even in the "control device for an engine-driven generator for an electric vehicle" disclosed in this publication, similarly to the above, when the battery voltage is equal to or lower than a predetermined value, the battery can be stopped even when the vehicle is stopped. In order to charge the battery, the engine driven generator is driven, which is not preferable in terms of fuel efficiency, exhaust gas and engine noise.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide a hybrid electric vehicle which improves fuel efficiency and suppresses generation of exhaust gas and noise.

[0010]

According to a first aspect of the present invention, there is provided a hybrid electric vehicle, comprising: a generator driven by an engine; a battery charged by power supplied from the generator; A traveling motor driven by power supply from the battery, a shift range selecting means for selecting a shift range of the vehicle by operating a driver, a charge state detecting means for detecting a charge state of the battery, A hybrid electric vehicle comprising: engine operation control means for driving the engine when the state of charge of the battery detected by the state-of-charge detection means falls below a predetermined state. The charge state detection means detects when the shift range of the vehicle selected by the means is the stop position. It is characterized in that the stops regardless the engine to the state of charge of the battery.

Therefore, the battery is charged with predetermined power in advance, and the engine operation control means stops the engine when the charge state of the battery detected by the charge state detection means is equal to or higher than the predetermined state, The vehicle is driven by driving the drive motor by power supply from the battery. On the other hand, when the charged amount of the battery decreases and the engine operation control means drives the engine when the state of charge of the battery detected by the state-of-charge detection means falls below a predetermined state, the engine generates a generator. The battery is charged by the power supply from the generator, and the vehicle is driven by driving the driving motor. At this time, if the shift range of the vehicle selected by the shift range selection means is the stop position, the engine operation control means stops the engine regardless of the state of charge of the battery. As described above, when the vehicle stops during hybrid traveling, the engine is stopped, so that wasteful consumption of fuel due to operation of the engine is suppressed, and generation of exhaust gas and noise is also suppressed.

Also, in the hybrid electric vehicle according to the present invention, the engine operation control means includes a battery which is detected by the charge state detection means when the shift range of the vehicle selected by the shift range selection means is at the reverse position. The engine is stopped regardless of the charging state.

Therefore, if the shift range of the vehicle selected by the shift range selection means is at the reverse position during hybrid driving, the engine operation control means stops the engine irrespective of the state of charge of the battery. When the vehicle travels backward when the traveling distance is short, the engine is stopped, and unnecessary fuel consumption due to operation of the engine is suppressed, and the generation of exhaust gas and noise is also suppressed.

Further, in the hybrid electric vehicle according to the present invention, the engine operation control means selects the shift range selection means when the state of charge of the battery detected by the state of charge detection means falls below a predetermined state. When the shift range of the vehicle
The engine is idled for a predetermined time and then stopped.

Therefore, if the shift range of the vehicle selected by the shift range selection means is at the stop position during hybrid driving, the engine operation control means stops the engine irrespective of the state of charge of the battery. Is stopped after idling for a predetermined period of time, so that the engine does not suddenly stop from the power generation operation state, and adverse effects on the engine are prevented.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a schematic configuration of a hybrid electric vehicle according to one embodiment of the present invention, FIG. 2 shows a flowchart of traveling control by the hybrid electric vehicle of this embodiment, and FIG. 3 shows a flowchart of control during hybrid traveling.

In the hybrid electric vehicle of this embodiment, as shown in FIG. 1, an output shaft of a traveling motor 11 is drivingly connected to left and right driving wheels 13 via a transmission 12. The traveling motor 11 includes an inverter 1
4 is connected to the battery 15 and the generator 1
6 and the engine 17 are connected. The inverter 14, the generator 16, and the engine 17 are connected to a controller 18 serving as an engine operating means.
6. The engine 17 can be controlled. The battery 15 has a charge capacity sensor 1 serving as a charge state detection means.
9, the detection signal is input to the controller 18, and it is possible to switch between battery running and hybrid running based on the detection signal.

That is, if the capacity of the electric power stored in the battery 15 is equal to or larger than a predetermined value, the battery runs, and the controller 18 stops the generator 16 and the engine 17, and the electric power stored in the battery 15 is Inverter 1
4 and is supplied to and driven by the traveling motor 11. On the other hand, if the capacity of the electric power stored in the battery 15 decreases and becomes equal to or less than a predetermined value, the hybrid vehicle runs and the generator 16
And the engine 17 is driven, and the electric power generated by the generator 16 is stored in the battery 15 while being supplied to the traveling motor 11 via the inverter 14 to be driven.

The controller 18 includes an engine speed sensor 20, a vehicle speed sensor 21, and a shift position sensor 2.
2 are connected. The engine speed sensor 20 detects the speed of the engine 17, the vehicle speed sensor 21 detects the vehicle speed, and the shift position sensor 22 determines the shift range (P, R, N, D, 2, 1) of a shift lever (not shown). Detect
By outputting each detection result to the controller 18, the controller 18 controls the driving of the motor 11 and the driving of the engine 17 and the generator 16 during hybrid running based on the engine speed, the vehicle speed, and the shift range. I have.

When the main switch (not shown) is turned on in the hybrid electric vehicle of this embodiment having the above-described configuration, as shown in FIG. 2, in step S11, the charge capacity sensor 19 detects the electric power stored in the battery 15 in step S11. Is detected and output to the controller 18. This controller 18 has a remaining battery capacity E of 50
%, The process proceeds to step S12.
Here, the battery running mode is set. On the other hand, if the remaining battery capacity E is 50% or less, the controller 18 proceeds to step 13 and sets the hybrid driving mode.

In the battery running mode, the controller 18 stops the generator 16 and the engine 17,
The electric power stored in the battery 15 is supplied to and driven by the traveling motor 11 via the inverter 14, and the driving wheels 13 connected to the traveling motor 11 via the transmission 12 are driven.
To run the electric vehicle. In the hybrid driving mode, the controller 18 sets the generator 16 and the engine 17 in a driving state, and stores the electric power generated by the
The driving wheel 11 is connected to the driving motor 11 via a transmission 12 and is driven by the driving wheel 11.
To run the electric vehicle.

In the hybrid running mode, as described above, the controller 18 controls the driving of the engine 17 based on the engine speed, the vehicle speed, and the shift range. That is, as shown in FIG.
At 21, the vehicle speed sensor 21 detects the vehicle speed V and determines whether the vehicle is running. If the vehicle is running, the engine 17 is operated at a predetermined rotation speed so that the generator 16 can generate power in step S22.

On the other hand, if the vehicle is not running, step S
The process proceeds to step 23, where the shift position sensor 22 detects the shift range (P, R, N, D, 2, 1) of the shift lever. That is, if the shift range of the shift lever is within the travel range (D, 2, 1) even though the vehicle is stopped, the vehicle is waiting for a traffic light or is temporarily stopped for getting on and off the occupant. Is determined, and the engine 17 is operated at the idle speed in step S24. If the vehicle is stopped and the shift range of the shift lever is in a stop range (P, R, N) other than the travel range (D, 2, 1), it is determined that the vehicle is in a parking state or the like, After performing the idle operation for a predetermined time (for example, 10 seconds) in step S25, the engine 17 is stopped.

Therefore, if the shift range of the shift lever is within the stop range (P, R, N), the remaining battery capacity E
The engine 17 is stopped even in the hybrid running mode in which the engine speed is reduced to a predetermined value or less. When the vehicle stops, the engine 17 is stopped, so that wasteful fuel consumption is suppressed and exhaust gas and Generation of noise is also suppressed. At this time, by adding the R range to the stop range, generation of noise when entering the garage at midnight or the like, and filling of exhaust gas during parking in the garage with a roof can be prevented. Further, when the shift range of the shift lever is in the stop range (P, R, N) in the hybrid traveling mode, the engine 17 is switched after a predetermined time (for example, 10 seconds) elapses.
Is stopped, the engine 17 does not suddenly stop from the power generation operation state, and adverse effects on the engine 17 are prevented.

In the hybrid electric vehicle of the present embodiment, the shift range of the shift lever is set to D, 2, 1 and the stop range is set to P, R, N.
May be removed and the stop range may be set only to P and N. Also,
Since the transmission 12 is an automatic transmission, the travel range is D, 2, 1, the stop range is P,
Although R and N are used, the transmission 12 may be a manual transmission.
3, 4, 5 and the stop range is neutral (and R).

[0027]

As described above in detail, according to the hybrid electric vehicle of the first aspect of the present invention, when the state of charge of the battery is equal to or higher than a predetermined state, the traveling motor is driven by power supply from the battery. on the other hand,
When the state of charge of the battery falls below a predetermined state, the engine is driven to charge the battery by power supply from the generator, and at the same time the drive motor can be driven, and when the shift range of the vehicle is at the stop position. Since the engine is stopped regardless of the state of charge of the battery, the engine is stopped when the vehicle is stopped during hybrid driving, so that unnecessary fuel consumption due to operation of the engine can be suppressed, and exhaust gas and noise are reduced. Can be suppressed.

According to the hybrid electric vehicle of the present invention, when the shift range of the vehicle is at the reverse position, the engine is stopped irrespective of the state of charge of the battery. During a short retreat, the engine is stopped, so that useless fuel consumption due to operation of the engine can be suppressed, and generation of exhaust gas and noise can be suppressed.

According to the third aspect of the present invention, when the state of charge of the battery drops below a predetermined state and the shift range of the vehicle is at the stop position, the engine is idled for a predetermined time. After that, the engine is not suddenly stopped from the power generation operation state, so that an adverse effect on the engine can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hybrid electric vehicle according to an embodiment of the present invention.

FIG. 2 is a flowchart of traveling control by the hybrid electric vehicle according to the embodiment.

FIG. 3 is a flowchart of control during hybrid traveling.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Traveling motor 12 Transmission 14 Inverter 15 Battery 16 Generator 17 Engine 18 Controller 19 Charge capacity sensor 20 Engine speed sensor 21 Vehicle speed sensor 22 Shift position sensor

Claims (3)

[Claims] 1. A generator driven by an engine;
A battery charged by power supply from the generator, a traveling motor driven by power supply from the generator or the battery, and shift range selection means for selecting a shift range of the vehicle by operation of a driver. Charge state detection means for detecting a charge state of the battery; and engine operation control means for driving the engine when the charge state of the battery detected by the charge state detection means falls below a predetermined state. In the hybrid electric vehicle, the engine operation control unit includes the engine operation unit irrespective of the state of charge of the battery detected by the state of charge detection unit when the shift range of the vehicle selected by the shift range selection unit is at a stop position. A hybrid electric vehicle characterized by stopping the operation. 2. The hybrid electric vehicle according to claim 1, wherein the engine operation control unit detects the charge state detection unit when the shift range of the vehicle selected by the shift range selection unit is at the reverse position. A hybrid electric vehicle, wherein the engine is stopped regardless of a state of charge of the battery. 3. The hybrid electric vehicle according to claim 1, wherein said engine operation control means includes means for controlling said shift range selecting means when said state of charge of said battery detected by said state of charge detection means falls below a predetermined state. Wherein when the shift range of the selected vehicle is a stop position, the engine is idled for a predetermined time and then stopped.