Power generation control system and method

• US 20070029800A1
• Filed: 08/08/2006
• Published: 02/08/2007
• Est. Priority Date: 08/08/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Miwa, Makoto, Yamashita, Yukihiro, Isobe, Daiji
• Granted Patent: US 7,460,947 B2
• Time in Patent Office: Days
• US Class Current: 290/40.C
• CPC Class Codes: F02B 17/005 having direct injection in the combustion chamber
• CPC Class Codes: F02B 2075/125 Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
• CPC Class Codes: F02B 23/104 the injector being placed on a side position of the cylinder
• CPC Class Codes: F02D 2200/0625 Fuel consumption, e.g. measured in fuel liters per 100 kms or miles per gallon
• CPC Class Codes: F02D 29/06 peculiar to engines driving electric generators
• CPC Class Codes: F02D 41/3029 further comprising a homogeneous charge spark-ignited mode
• CPC Class Codes: F02D 41/3076 with special conditions for selecting a mode of combustion, e.g. for starting, for diagnosing
• CPC Class Codes: H02P 9/04 Control effected upon non-electric prime mover and dependent upon electric output value of the generator

Abstract

A control unit uses upper and lower limit guard values to limit a power generation quantity of a power generator and thereby to maintain the current combustion mode during power generation of the power generator. The control unit computes a remaining electric charge of a battery. When the remaining electric charge drops to a predetermined value or below, the control unit cancels a combustion mode maintaining operation, which maintains the current combustion mode, is cancelled, so that priority is given to the power generation of the power generator to recover the remaining electric charge of the battery. Also, when an electric power consumption in a vehicle is equal to or greater than a predetermined value, the combustion mode maintaining operation is cancelled, and the power generation quantity of the power generator is controlled in a manner that does not cause overdischarge of the battery.

Claims

1. A power generation control system for an internal combustion engine of a vehicle, which changes a combustion mode based on an operational condition, the power generation control system comprising:

a power generator that is driven by a drive force of the internal combustion engine to generate electric power;

a battery that stores the electric power, which is generated by the power generator; and

a power generation control means for controlling a power generation quantity of the power generator, wherein the power generation control means controls the power generation quantity of the power generator in a manner that maintains a current combustion mode of the internal combustion engine.

2. The power generation control system according to claim 1, further comprising an exhaust gas predicting means for predicting a noxious component output quantity increase in exhaust gas of the internal combustion engine caused by power generation of the power generator, wherein:

the exhaust gas predicting means predicts;

a noxious component output quantity in the exhaust gas of the internal combustion engine in a generator operating state where the power generation of the power generator is performed during operation of the internal combustion engine; and

a noxious component output quantity in the exhaust gas of the internal combustion engine in a generator non-operating state where the power generation of the power generator is stopped during the operation of the internal combustion engine;

the exhaust gas predicting means predicts the noxious component output quantity increase based on a difference between the noxious component output quantity in the generator operating state and the noxious component output quantity in the generator non-operating state; and

the power generation control means controls the power generation quantity of the power generator in view of the noxious component output quantity increase in the manner that maintains the current combustion mode of the internal combustion engine.

3. The power generation control system according to claim 1, further comprising a fuel consumption quantity predicting means for predicting a fuel consumption quantity increase of the internal combustion engine caused by power generation of the power generator, wherein:

the fuel consumption quantity predicting means predicts;

a fuel consumption quantity of the internal combustion engine in a generator operating state where the power generation of the power generator is performed during operation of the internal combustion engine; and

a fuel consumption quantity of the internal combustion engine in a generator non-operating state where the power generation of the power generator is stopped during the operation of the internal combustion engine;

the fuel consumption quantity predicting means predicts the fuel consumption quantity increase based on a difference between the fuel consumption quantity in the generator operating state and the fuel consumption quantity in the generator non-operating state; and

the power generation control means controls the power generation quantity of the power generator in view of the fuel consumption increase in the manner that maintains the current combustion mode of the internal combustion engine.

4. The power generation control system according to claim 1, further comprising a remaining electric charge determining means for determining a remaining electric charge of the battery, wherein:

the power generation control means determines whether priority should be given to charging of the battery over maintaining of the current combustion mode based on the remaining electric charge of the battery determined by the remaining electric charge determining means; and

when the power generation control means determines that the priority should be given to the charging of the battery over the maintaining of the current combustion mode, the power generation control means controls the power generation quantity of the power generator without requiring the maintaining of the current combustion mode of the internal combustion engine.

5. The power generation control system according to claim 1, further comprising a power consumption determining means for determining an electric power consumption in the vehicle, wherein:

the power generation control means determines whether priority should be given to generating of the electric power by the power generator over maintaining of the current combustion mode based on the electric power consumption determined by the power consumption determining means; and

when the power generation control means determines that the priority should be given to the generating of the electric power by the power generator over the maintaining of the current combustion mode, the power generation control means controls the power generation quantity of the power generator without requiring the maintaining of the current combustion mode of the internal combustion engine.

6. A power generation control system for an internal combustion engine of a vehicle, which changes a combustion mode based on an operational condition, the power generation control system comprising:

a power generator that is driven by a drive force of the internal combustion engine to generate electric power;

a battery that stores the electric power, which is generated by the power generator; and

a controller that controls a power generation quantity of the power generator, wherein the controller controls the power generation quantity of the power generator in a manner that maintains a current combustion mode of the internal combustion engine.

7. The power generation control system according to claim 6, wherein:

the controller predicts a noxious component output quantity in exhaust gas of the internal combustion engine in a generator operating state where power generation of the power generator is performed during operation of the internal combustion engine;

the controller predicts a noxious component output quantity in the exhaust gas of the internal combustion engine in a generator non-operating state where the power generation of the power generator is stopped during the operation of the internal combustion engine;

the controller predicts a noxious component output quantity increase in exhaust gas of the internal combustion engine caused by the power generation of the power generator based on a difference between the noxious component output quantity in the generator operating state and the noxious component output quantity in the generator non-operating state; and

the controller controls the power generation quantity of the power generator in view of the noxious component output quantity increase in the manner that maintains the current combustion mode of the internal combustion engine.

8. The power generation control system according to claim 6, wherein:

the controller predicts a fuel consumption quantity of the internal combustion engine in a generator operating state where power generation of the power generator is performed during operation of the internal combustion engine;

the controller predicts a fuel consumption quantity of the internal combustion engine in a generator non-operating state where the power generation of the power generator is stopped during the operation of the internal combustion engine;

the controller predicts a fuel consumption quantity increase of the internal combustion engine caused by the power generation of the power generator based on a difference between the fuel consumption quantity in the generator operating state and the fuel consumption quantity in the generator non-operating state; and

the controller controls the power generation quantity of the power generator in view of the fuel consumption increase in the manner that maintains the current combustion mode of the internal combustion engine.

9. The power generation control system according to claim 6, wherein:

the controller determines whether priority should be given to charging of the battery over maintaining of the current combustion mode based on a remaining electric charge of the battery; and

when the controller determines that the priority should be given to the charging of the battery over the maintaining of the current combustion mode, the controller controls the power generation quantity of the power generator without requiring the maintaining of the current combustion mode of the internal combustion engine.

10. The power generation control system according to claim 6, wherein:

the controller determines whether priority should be given to generating of the electric power by the power generator over maintaining of the current combustion mode based on an electric power consumption in the vehicle; and

when the controller determines that the priority should be given to the generating of the electric power by the power generator over the maintaining of the current combustion mode, the controller controls the power generation quantity of the power generator without requiring the maintaining of the current combustion mode of the internal combustion engine.

11. A power generation control method for an internal combustion engine of a vehicle, which changes a combustion mode based on an operational condition, the power generation control method comprising:

operating the internal combustion engine in one of a plurality of combustion modes; and

operating a power generator in a manner that maintains the current combustion mode of the internal combustion engine.

12. The power generation control method according to claim 11, further comprising:

predicting a noxious component output quantity in exhaust gas of the internal combustion engine in a generator operating state where power generation of the power generator is performed during operation of the internal combustion engine;

predicting a noxious component output quantity in the exhaust gas of the internal combustion engine in a generator non-operating state where the power generation of the power generator is stopped during the operation of the internal combustion engine; and

predicting a noxious component output quantity increase in exhaust gas of the internal combustion engine caused by the power generation of the power generator based on a difference between the noxious component output quantity in the generator operating state and the noxious component output quantity in the generator non-operating state; and

controlling the power generation quantity of the power generator in view of the noxious component output quantity increase in the manner that maintains the current combustion mode of the internal combustion engine.

13. The power generation control method according to claim 11, further comprising:

predicting a fuel consumption quantity of the internal combustion engine in a generator operating state where power generation of the power generator is performed during operation of the internal combustion engine; and

predicting a fuel consumption quantity of the internal combustion engine in a generator non-operating state where the power generation of the power generator is stopped during the operation of the internal combustion engine;

predicting a fuel consumption quantity increase of the internal combustion engine caused by the power generation of the power generator based on a difference between the fuel consumption quantity in the generator operating state and the fuel consumption quantity in the generator non-operating state; and

controlling the power generation quantity of the power generator in view of the fuel consumption increase in the manner that maintains the current combustion mode of the internal combustion engine.

14. The power generation control method according to claim 11, further comprising:

determining whether priority should be given to charging of the battery over maintaining of the current combustion mode based on a remaining electric charge of the battery; and

controlling the power generation quantity of the power generator without requiring the maintaining of the current combustion mode of the internal combustion engine when it is determined that the priority should be given to the charging of the battery over the maintaining of the current combustion mode.

15. The power generation control method according to claim 11, further comprising:

determining whether priority should be given to generating of the electric power by the power generator over maintaining of the current combustion mode based on an electric power consumption in the vehicle; and

controlling the power generation quantity of the power generator without requiring the maintaining of the current combustion mode of the internal combustion engine when it is determined that the priority should be given to the generating of the electric power by the power generator over the maintaining of the current combustion mode.