Method and apparatus for managing charge/discharge current of on-vehicle battery to control on-vehicle generator in consideration of offset of charge/discharge current

• US 20080036423A1
• Filed: 08/10/2007
• Published: 02/14/2008
• Est. Priority Date: 08/10/2006
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Asada, Tadatoshi
• Granted Patent: US 7,750,602 B2
• Time in Patent Office: Days
• US Class Current: 320/134
• CPC Class Codes: H02J 7/163 with special means for initiating or limiting the excitation current

Abstract

An apparatus is provided to manage a charge/discharge current of an on-vehicle battery. The apparatus comprises a detecting unit detecting an actual amount of the charge/discharge current and a receiving unit receiving information indicating generating operations of an on-vehicle generator. The apparatus also comprises a control unit controlling the generating operations of the generator so that the charge/discharge current keeps a given value specified, on the basis of the detected actual the charge/discharge current and the received information. The apparatus also comprises determining and setting units. The determining unit determines whether a voltage of the battery satisfies a given condition for the voltage, by monitoring the voltage in a state where the generating operation of the generator is controlled. The setting unit sets, as an amount of offset of the charge/discharge current, a charge/discharge current detected when it is determined that the voltage of the battery satisfies the given condition.

Claims

1. An apparatus for managing a charge/discharge current of a battery mounted on a vehicle, comprising:

a detecting unit that detects an actual amount of the charge/discharge current;

a receiving unit that receives information indicative of a generating operation of a generator mounted on the vehicle;

a control unit controls the generating operation of the generator so that the charge/discharge current of the battery keeps a given value specified for the charge/discharge current, on the basis of the detected actual amount of the charge/discharge current and the received information indicative of the generating operation of the generator;

a determining unit that determines whether or not a voltage of the battery satisfies a given condition for the voltage, by monitoring the voltage in a state where the generating operation of the generator is controlled by the control unit; and

a setting unit that sets, as an amount of offset of the charge/discharge current, a charge/discharge current detected by the detecting unit when it is determined by the determining unit that the voltage of the battery satisfies the given condition.

2. The apparatus of claim 1, wherein

the information indicative of the generating operation of the generator is the number of revolutions of the generator and

the determining unit is configured to determine, as the given condition for the voltage, whether or not the number of revolutions is within a given range of revolutions.

3. The apparatus of claim 1, wherein

the information indicative of the generating operation of the generator is an excitation current supplied to the generator and

the determining unit is configured to determine, as the given condition for the voltage, whether or not the excitation current is within a given range of the excitation current.

4. The apparatus of claim 1, wherein

the information indicative of the generating operation of the generator is the number of revolutions of the generator and an excitation current supplied to the generator and

the determining unit is configured to determine, as the given condition for the voltage, whether or not the number of revolutions is within a given range of revolutions and whether or not the excitation current is within a given range of the excitation current.

5. The apparatus of claim 1, wherein

the control unit is configured to control, as the generating operation of the generator, an excitation current to the generator so that an output current from the generator is variably controlled.

6. The apparatus of claim 1, wherein

the detecting unit comprises a resistor inserted in series into a path through which the charge/discharge current of the battery is supplied and is configured to detect the amount of the charge/discharge current based on a voltage across the resistor.

7. The apparatus of claim 6, wherein

the resistor is electrically connected with a negative terminal of the battery and is eclectically connected to the ground.

8. The apparatus of claim 1, wherein

the receiving unit is configured to receive the information indicative of the generating operation of the generator from an external apparatus on digital communication.

9. The apparatus of claim 8, wherein

the receiving unit is configured to receive the information at intervals which are equal to or less than approximately 1/10 of a time constant of a rotator of the generator.

10. The apparatus of claim 1, further comprising:

an estimating unit that estimates a capacity of the battery based on the actual amount of the charge/discharge current detected by the detecting unit and the offset of the charge/discharge current set by the setting unit; and

a transmitting unit that transmits information indicative of the estimated capacity of the battery to an external apparatus.

11. A method for managing a charge/discharge current of a battery mounted on a vehicle, comprising steps of:

detecting an actual amount of the charge/discharge current;

receiving information indicative of an generating operation of a generator mounted on the vehicle;

controlling the generating operation of the generator so that the charge/discharge current of the battery keeps a given value specified for the charge/discharge current, on the basis of the detected actual amount of the charge/discharge current and the received information indicative of the generating operation of the generator;

determining whether or not a voltage of the battery satisfies a given condition for the voltage, by monitoring the voltage in a state where the generating operation of the generator is controlled; and

setting, as an amount of offset of the charge/discharge current, a charge/discharge current detected when it is determined that the voltage of the battery satisfies the given condition.

12. The method of claim 11, wherein

the information indicative of the generating operation of the generator is the number of revolutions of the generator and

the determining step determines, as the given condition for the voltage, whether or not the number of revolutions is within a given range of revolutions.

13. The method of claim 11, wherein

the information indicative of the generating operation of the generator is an excitation current supplied to the generator and

the determining step determines, as the given condition for the voltage, whether or not the excitation current is within a given range of the excitation current.

14. The method of claim 11, wherein

the information indicative of the generating operation of the generator is the number of revolutions of the generator and an excitation current supplied to the generator and

the determining step determines, as the given condition for the voltage, whether or not the number of revolutions is within a given range of revolutions and whether or not the excitation current is within a given range of the excitation current.