Prime-mover dynamo plants – Electric control – Engine control
Reexamination Certificate
1997-06-25
2001-04-10
Enad, Elvin (Department: 2834)
Prime-mover dynamo plants
Electric control
Engine control
C290S04000F, C290S04000F, C290S04000F
Reexamination Certificate
active
06215198
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a generating control device for a hybrid vehicle which includes an engine, a generator driven by the output of the engine, a battery and a control unit for controlling operations of these elements.
In recent years, a series hybrid electric vehicle (SHEV) equipped with a generator-and an engine for driving it, has been developed in order to increase a cruising range of an electric vehicle. In this art, it is also known a system which is installed in the hybrid vehicle and which allows it to travel by electric energy supplied from a battery when the battery is charged fully. On the other hand, when the charged energy in the battery decreases, the system starts the engine in order to charge the battery by electric power supplied from the generator. Thereafter, when the charging amount reaches a prescribed value, the engine is inacivated.
In such a series hybrid electric vehicle, if the engine of the vehicle is used little in comparison with that of a gasoline-fueled automobile (not electrical car), the vehicle exhibits a low-pollution car on one hand. On the other hand, depending on methods of controlling the engine and the generator, there is a possibility to cause pollution problems equal to or greater more than those of the gasoline-fueled automobile.
Furthermore, it is supposed that, depending on the control method of the generator, repeated overcharging or overdischarging operations for the battery may cause the battery's life span to be shortened in comparison with that of an electric car, so that cost and time for exchanging the battery (or batteries) with another may be increased disadvantageously.
In the prior art, for example, Japanese Unexamined Patent Publication (Kokai) No. 5-32852 discloses one of the conventional generating control devices for the hybrid vehicles. This generating control device operates to drive the generator for assisting the battery in response to loads of the drive motor in the hybrid electrical vehicle, while the device judges the loads according to the charged energy in the battery, an opening of an accelerator pedal, degree of slope etc. and adjusts an opening of a throttle valve.
In the above-mentioned conventional generating control device of the hybrid vehicle, however, the battery deteriarates quickly since the device is not able to determine if the battery cannot be charged or discharged.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a generating control device of a hybrid electric vehicle (SHEV), which is capable of restricting the battery from deteriorating and which can ensure fine driving performance of the vehicle.
The object of the present invention described above can be accomplished by a generating control device for a hybrid vehicle, comprising:
a motor for driving the hybrid vehicle;
a battery for driving the motor;
a generator for supplying the motor and the battery with electric power;
an engine for driving the generator; and
control means for changing operations of the generator and the engine in accordance with a plurality of operational modes for restricting the battery from deteriorating. With the arrangement mentioned above, by changing the operations of the generator and the motor according to the plural modes for restricting the battery from deteriorating, it is possible to reduce the deterioration of the battery of the hybrid vehicle and to ensure the fine driving performance.
In the present invention, preferably, the control means carries out judgment of the operational modes on the basis of battery temperature of the battery. In this case, by carrying out the judgment of mode on the basis of the battery temperature, it is possible to reduce the deterioration of the battery of the hybrid vehicle and to ensure the fine driving performance.
More preferably, the control means carries out judgment of the operational modes on the basis of battery temperature of the battery, electrical energy charged in the battery and a required driving force the motor should be induce to produce. Also in this case, by carrying out the judgment of mode on the basis of the battery temperature, the charged energy in the battery and the required motor output, it is possible to reduce the deterioration of the battery of the hybrid vehicle.
In the present invention, it is preferable that when the battery temperature exceeds a prescribed temperature, the control means prohibits the charging and discharging operation of the battery and drives the engine at a constant engine speed, so that generating energy can be produced by the generator in response to a required motor output. Also in this case, it is possible to reduce the deterioration of the battery of the hybrid vehicle and to ensure fine driving performance.
It is preferable that when the battery can charge or discharge and it is required to allow the generating energy of the generator to follow the required motor output, the control means operates to drive the generator at a constant torque and controls the generating energy on the basis of the present engine speed. Also in this case, it is possible to reduce the deterioration of the battery of the hybrid vehicle and to ensure fine driving performance.
More preferably, when the battery is one which exhibits an endothermic reaction during its charging operation, the control means establishes the generating energy by adding charging energy corresponding to the endothermic reaction to the required motor output operates to drive the generator at a constant torque and controls the generating energy on the basis of the engine speed. In this case, it is possible to reduce the deterioration of the battery of the hybrid vehicle and to ensure fine driving performance.
The above and other features and advantages of this invention will become apparent, and the invention itself will best be understood, from a study of the following description and appended claims, with reference had to the attached drawings showing a preferred embodiment of the invention.
REFERENCES:
patent: 4335429 (1982-06-01), Kawakatsu
patent: 5264764 (1993-11-01), Kuang
patent: 5345761 (1994-09-01), King et al.
patent: 5359228 (1994-10-01), Yoshida
patent: 5492190 (1996-02-01), Yoshida
patent: 5623197 (1997-04-01), Roseman et al.
patent: 5659240 (1997-08-01), King
patent: 5713814 (1998-02-01), Hara et al.
patent: 5760486 (1998-06-01), Uchinami et al.
patent: 5821706 (1998-10-01), Koga
patent: 5-328522 (1993-12-01), None
Aso Takeshi
Hirano Hiroyuki
Inada Eiji
Kaneko Yuutarou
Kikuchi Toshio
Enad Elvin
McDermott & Will & Emery
Nissan Motor Co,. Ltd.
LandOfFree
Generating control device for hybrid vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Generating control device for hybrid vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Generating control device for hybrid vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2471488