JP3646305B2 - Hybrid car - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hybrid vehicle.
[0002]
[Prior art]
There is known a hybrid vehicle that includes an engine and a motor as power sources and has a configuration that transmits these driving forces via a clutch (for example, Japanese Patent Application Laid-Open No. 11-348603). Such a hybrid vehicle has a problem that a torque shock occurs when a power source is switched or added. In this hybrid vehicle, when the power is switched from the motor to the engine, the engine torque is absorbed by the generator, etc., and the motor and the engine speed are matched, and then the clutch for transmitting the engine power is engaged. Torque shock due to switching of power source is prevented.
[0003]
[Problems to be solved by the invention]
The problem of torque shock when switching or adding the power source of a hybrid vehicle using a clutch is that when the power is switched from a state where it is driven only by the engine to a motor, or when it is driven only by the engine This also occurs when the motor driving force is added to the motor.
[0004]
The present invention has been made in view of this problem, and an object of the present invention is to provide a hybrid vehicle having a small torque shock when switching to a driving force by a motor or adding a driving force by a motor.
[0005]
[Means for Solving the Problems]
According to the present invention, there is provided a hybrid vehicle that travels by using a traveling motor that generates driving force by power of a battery and an engine, and includes the traveling motor and wheels driven by the traveling motor. A clutch arranged in between, a detecting means for detecting the rotational speed of the wheel side, and when the clutch is engaged, the travel motor is rotated, and the minimum value of the rotational speed at which the travel motor varies is the wheel side And a clutch control means for engaging the clutch and driving the wheel by the travel motor when the rotation number becomes equal to or greater than the number of revolutions.
[0006]
According to such a configuration, when the rotation speed on the motor side becomes larger than the rotation speed on the wheel side, the motor and the wheel driven by the clutch are connected by clutch engagement. Acts on the wheel side in the acceleration direction. For this reason, a torque shock becomes small. Furthermore, even if the motor rotation speed is “uneven”, the clutch is securely engaged with the motor rotation speed being high.
[0007]
According to another aspect of the present invention, a hybrid vehicle that travels by using a traveling motor that generates a driving force by the power of a battery and an engine, which is driven by the traveling motor and the traveling motor. A clutch disposed between the wheels to be detected, a detecting means for detecting the rotational speed of the wheel side, and when the clutch is engaged, the travel motor is rotated, and the minimum rotational speed of the travel motor is changed. When the value becomes a value between the number of revolutions on the wheel side and a number of revolutions higher than the number of revolutions on the wheel side, the clutch is engaged and the wheel is driven by the traveling motor. There is provided a hybrid vehicle comprising a clutch control means.
[0008]
Even with such a configuration, even if the motor rotation speed is “uneven”, the clutch is securely engaged with the motor rotation speed being high.
[0009]
According to another aspect of the present invention, a hybrid vehicle that travels by using a traveling motor that generates a driving force by the power of a battery and an engine, which is driven by the traveling motor and the traveling motor. A clutch disposed between the wheels to be detected, a detecting means for detecting the rotational speed of the wheel side, and when the clutch is engaged, the travel motor is rotated, and the minimum rotational speed of the travel motor is changed. A hybrid vehicle comprising: clutch control means for fastening the clutch and driving the wheel with the travel motor when the value is substantially equal to the rotation speed on the wheel side. Provided.
[0010]
Even with such a configuration, even if the motor rotation speed is “uneven”, the clutch is securely engaged with the motor rotation speed being high.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. First, an automobile 1 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram illustrating a schematic configuration of an automobile 1 according to the present embodiment. The automobile of this embodiment is a so-called standby four-wheel drive in which the front wheels are always driven by the engine 2 and when the front wheels slip, the rear wheels are driven by a battery-operated motor. The battery is charged not only by a generator operated by the engine but also by regeneration performed when the vehicle is decelerated and the wheel slips.
[0012]
As shown in FIG. 1, the automobile 1 includes an engine 2 and a traveling motor 6 driven by electric power supplied from a battery 4 as a power unit. The engine 2 always drives the left and right front wheels 10 and 10 via the AT 8 and the like, and the traveling motor 6 is connected to the rear wheels via the engaged electromagnetic clutch 12 and the like under predetermined conditions such as the front wheels slipping. 14 and 14 are driven.
[0013]
The engine 2 drives a generator 20 for charging a battery via the belt 16 and the electromagnetic clutch 18. The traveling motor 6 is, for example, an IPM synchronous motor, and the battery 4 is mounted with, for example, a nickel metal hydride battery. The battery 4 is also connected to an in-vehicle electric device 22 such as a motor, a defroster, and a hot wire wind defogger for driving an air conditioner compressor. The battery 4 is, for example, about 42V 20 amperes / hour, and the traveling motor 6 is, for example, about 10 kw.
[0014]
The automobile 1 includes an ECU 24. The ECU 24 includes a CPU, a ROM, a RAM, an interface circuit, an inverter circuit, and the like. The ECU 24 receives signals from various sensors such as a throttle opening sensor and a wheel speed sensor, and controls engine timing such as ignition timing and fuel injection, charging control to the battery 4 and charging from the battery 4, etc. Various controls relating to the automobile 1 such as the operation control of the electric device 22 are performed in an integrated manner.
[0015]
Next, the operation of the engine 2, the generator 20, the traveling motor 6, and the battery 4 that are components of the automobile 1 will be described for each traveling state.
[0016]
(When stopped)
When the vehicle stops, the engine 2, the generator 20, and the traveling motor 6 are stopped. However, the engine 2 is operated when it is cold and when the stored amount of the battery 4 is reduced, and the battery 4 is charged by the generator 20.
[0017]
(When starting slowly)
At the time of slow start, the engine 2 is operated, and the front wheels are driven by the driving force to start. The generator 20 is operated as necessary when the amount of power stored in the battery 4 is reduced.
[0018]
(In case of sudden start)
At the time of sudden start, the engine 2 is operated, and the traveling motor 6 is also operated, and the four wheels are driven by these driving forces to start. The generator 20 is operated as necessary when the amount of power stored in the battery 4 is reduced.
[0019]
(During steady driving)
During steady running, the engine 2 is operated, and the front wheels 10 and 10 are driven by this driving force. The generator 20 is operated as necessary when the amount of power stored in the battery 4 is reduced. That is, when the charged amount of the battery 4 becomes a predetermined value or less, the clutch 18 disposed between the engine 2 and the generator 20 is engaged and the generator 20 is driven to charge the battery 4. When the amount reaches a predetermined value (necessary amount), the clutch 18 is disengaged and normal charging control is performed such that the operation of the generator 20 is stopped.
[0020]
(During four-wheel drive)
Four-wheel drive is performed during low-μ road travel, rough road travel, and rapid acceleration, and the engine 2 drives the front wheels 10 and 10, and the travel motor 6 drives the rear wheels 14 and 14. In addition, when traveling on low μ roads and bad roads where the travel motor 6 is driven frequently and the amount of charge of the battery tends to decrease, in principle, the clutch 18 is always engaged and the generator 20 generates power. The battery 4 is charged.
[0021]
(During deceleration)
When decelerating, that is, when the brake pedal is operated and when the drive wheel slips, in principle, the generator 20 and the traveling motor 6 are operated as a generator to convert (regenerate) the kinetic energy of the automobile 1 into electric energy. Then, the battery 4 is charged. This regeneration control is also performed by the ECU 24.
[0022]
Next, the control performed when shifting to the four-wheel drive traveling mode will be described. As described above, the vehicle 1 of the present embodiment shifts to the four-wheel drive travel mode in which the rear motors 14 and 14 are driven by the travel motor 6 during low-μ road travel, rough road travel, or rapid acceleration. The control for switching to the four-wheel drive travel mode is performed by the ECU 24.
[0023]
In the embodiment of the present embodiment, the travel motor 6 drives the rear wheel 14 by operating the travel motor 6 and fastening the clutch 12 disposed between the travel motor 6 and the rear wheel 14. Make it ready. When the clutch 12 is engaged, the ECU 24 rotationally drives the traveling motor 6 prior to the engagement of the clutch 12 in order to suppress torque shock due to the engagement, and the rotational speed of the traveling motor 6 is determined by the rear wheel of the clutch 12. When the target rotational speed exceeding the rotational speed of the 14 side portion is reached, the clutch 12 is engaged. Accordingly, the ECU 24 is configured to receive the rotational speed of the traveling motor 6, the rotational speed of the rear wheel 14 side portion of the clutch 12, and the like. The rotational speed of the traveling motor indicates the rotational speed that is the center of the motor when there is a fluctuation in the rotational speed.
[0024]
When the traveling motor 6 has a rotational speed variation, the ECU 24 detects the minimum rotational speed value or estimates it from the data of the traveling motor 6. The clutch 12 may be engaged when it becomes higher than the rotational speed of the wheel 14 side portion or when it becomes substantially the same.
[0025]
Furthermore, the minimum value of the changing rotational speed of the traveling motor 6 is higher by a predetermined value (α) than the rotational speed of the rear wheel 14 side portion of the clutch 12 and the rotational speed of the rear wheel 14 side portion of the clutch 12. The clutch 12 may be configured to be engaged by performing feedback control so that the target rotational speed is between the rotational speeds.
[0026]
This feedback control will be described along the flowchart of FIG. When the control is started, in step S1, data such as the rotational speed of the rear wheel 14 side portion of the clutch 12, that is, the target rotational speed (Nobj), the rotational speed of the traveling motor 6 is read, and in step S2, the feedback target rotational speed is read. (Nfb) is read, and further, in step S3, the minimum value (Nmin) of the rotational speed of the traveling motor 6 is read. Next, the process proceeds to step S4, and it is determined whether or not the minimum value (Nmin) of the rotational speed is smaller than the target rotational speed (Nobj) + α (α is a constant).
[0027]
If YES in step S4, that is, if the minimum value (Nmin) of the rotational speed is smaller than the target rotational speed (Nobj) + α (α is a constant), the process proceeds to step S5, and the minimum rotational speed value (Nmin) is set to the target rotational speed (Nmin). Nobj). When YES in step S4, that is, when the minimum value (Nmin) of the rotational speed is larger than the target rotational speed (Nobj), the minimum rotational speed value (Nmin) is equal to the rotational speed (Nobj) of the rear wheel 14 side portion of the clutch 12. Since the rotational speed is higher by a predetermined value (α) than the rotational speed (Nobj) of the rear wheel 14 side portion of the clutch 12, the routine returns and the clutch 12 is engaged.
[0028]
On the other hand, when NO in step S4 or step S5, the process proceeds to step S6, where the minimum value (Nmin) of the rotational speed is the rotational speed (Nobj) of the rear wheel 14 side portion of the clutch 12 and the rear wheel 14 of the clutch 12. The current feedback target rotational speed (Nfb) is corrected so as to enter between the rotational speeds higher than the rotational speed (Nobj) of the side portion by a predetermined value (α), and the process returns. Specifically, in step S6, K × (Nmin−Nobj) is added to the current feedback target rotational speed (Nfb), the feedback target rotational speed (Nfb) is corrected, and the process returns. K is a negative constant.
[0029]
Torque shock is reduced by engaging the clutch 12 by performing such feedback control.
[0030]
The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the scope of the matters described in the claims.
[0031]
The automobile of the above embodiment is an application of the present invention to a so-called standby four-wheel drive vehicle in which the rear wheels are driven by an electric motor at the time of front wheel slip driven by an engine. The present invention can also be applied to a hybrid vehicle, for example, a hybrid vehicle in which a front wheel that is always driven by an engine is assisted by an electric motor as necessary.
[0032]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the hybrid vehicle with a small torque shock when switching to the driving force by a motor or adding the driving force by a motor is provided.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of an automobile according to an embodiment.
FIG. 2 is a flowchart of feedback control performed by an ECU.
[Explanation of symbols]
2: Engine 4: Battery 6: Driving motor 10: Front wheel 12: Clutch 14: Rear wheel 20: Generator 22: On-vehicle electrical device 24: ECU

Claims (3)

A hybrid vehicle that travels in combination with a driving motor that generates driving force by the power of the battery and an engine,
A clutch disposed between the traveling motor and a wheel driven by the traveling motor;
Detecting means for detecting the rotational speed of the wheel side;
When the clutch is engaged, the travel motor is rotated, and when the minimum value of the variable speed of the travel motor is equal to or greater than the rotational speed on the wheel side, the clutch is engaged and the travel motor is Clutch control means for driving the wheels with a motor,
A hybrid vehicle characterized by that. A hybrid vehicle that travels in combination with a driving motor that generates driving force by the power of the battery and an engine,
A clutch disposed between the traveling motor and a wheel driven by the traveling motor;
Detecting means for detecting the rotational speed of the wheel side;
When the clutch is engaged, the travel motor is rotated, and the minimum value of the variable speed of the travel motor is between the rotational speed on the wheel side and the rotational speed higher than the rotational speed on the wheel side by a predetermined value. Clutch control means for fastening the clutch and driving the wheel with the travel motor when the value is reached.
A hybrid vehicle characterized by that. A hybrid vehicle that travels in combination with a driving motor that generates driving force by the power of the battery and an engine,
A clutch disposed between the traveling motor and a wheel driven by the traveling motor;
Detecting means for detecting the rotational speed of the wheel side;
When the clutch is engaged, the traveling motor is rotated, and when the minimum value of the changing speed of the traveling motor becomes substantially the same as the rotational speed on the wheel side, the clutch is engaged and the traveling motor is Clutch control means for driving the wheels with a motor,
A hybrid vehicle characterized by that.

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