Power controller for a vehicle

• US 20040232881A1
• Filed: 06/15/2004
• Published: 11/25/2004
• Est. Priority Date: 03/01/2000
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Masaki, Ryoso, Morooka, Yasuo, Amano, Masahiko
• Granted Patent: US 6,979,977 B2
• Time in Patent Office: Days
• US Class Current: 320/104
• CPC Class Codes: B60L 2210/12 Buck converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: F02N 11/0866 comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 2011/0888 DC/DC converters
• CPC Class Codes: F02N 2011/0896 Inverters for electric machines, e.g. starter-generators
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: H02J 9/002 in which a reserve is maintained in an energy source by disconnecting non-critical loads, e.g. maintaining a reserve of charge in a vehicle battery for starting an engine
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A power controller for a vehicle can operate electrical load upon stopping of engine or turning OFF of a key switch, and lowering of remaining capacity of a main battery can be prevented. The control system has a control portion controlling operation of a power generator and an electrical load mounted on an automotive vehicle. The control system also includes remaining capacity measuring means for measuring a remaining capacity of a battery. The control portion drives a predetermined power load when an engine is stopped or a key switch is held OFF, and operation of the power load is stopped when a remaining capacity of the battery measured by the remaining capacity measuring means becomes smaller than a predetermined value.

Claims

1. Automotive power source apparatus comprising:

a motor-generator connected to an engine;

an inverter connected to said motor-generator;

a first battery connected to said inverter, a converter connected to said first battery for converting the output voltage of said first battery into a predetermined voltage; and

a second battery connected to said converter;

wherein said second battery is charged by either said inverter or said first battery through said converter.

2. The automotive power source apparatus as set forth in claim 1, further comprising a power source control apparatus connected at least to said first battery and said converter, wherein said power source control apparatus regulates charging of said second battery by controlling an on-off state of said converter corresponding to the remaining capacity of said first battery.

3. The automotive power source apparatus as set forth in claim 1, further comprising a power source control apparatus connected at least to said first battery and said converter, wherein said power source control apparatus regulates charging to said second battery by controlling an on-off state of a load connected to said first battery or an on-off state of said converter, corresponding to the remaining capacity of said first battery.

4. The automotive power source apparatus as set forth in claim 1, further comprising a power source control apparatus connected at least to said first battery, said converter, and said secondary battery, wherein said power source control apparatus regulates charging to said second battery by controlling an on-off state of said converter corresponding to remaining capacity of said first battery, and controls an on-off state of a load connected to said second battery corresponding to a remaining capacity of said second battery.

5. The automotive power source apparatus as set forth in claim 2, wherein said power source control apparatus causes said motor-generator to operate to charge said first battery by turning off said converter corresponding to remaining capacity of said first battery.

6. The automotive power source apparatus as set forth in claim 5, wherein said motor-generator is driven by said first battery to start said engine, and said motor-generator charges said first battery after said engine is started.

7. The automotive power source apparatus as set forth in claim 6, wherein the driving of said engine is controlled corresponding to remaining capacity of fuel for driving said engine.

8. The automotive power source apparatus as set forth in claim 5, wherein driving of said engine or shutting off of a load connected to said first battery is controlled corresponding to a remaining amount of fuel for driving said engine.

9. The automotive power source apparatus as set forth in claim 2, wherein said power source control apparatus controls said power source apparatus such that power is supplied to a load connected to said second battery when said converter is controlled to an off state.

10. The automotive power source apparatus as set forth in claim 2, wherein:

said power source control apparatus controls said converter to an on state until the remaining capacity of said first battery reaches a first predetermined amount, and to an off state when said remaining capacity reaches said first predetermined amount; and

said power source control apparatus controls said power source apparatus such that power is supplied to a load connected to said second battery until the remaining capacity of said secondary battery reaches a second predetermined amount.

11. The automotive power source apparatus as set forth in claim 1, wherein said first battery has a voltage of at least 42V, and said second battery is a 14 V battery.

12. The automotive power source apparatus as set forth in claim 11, wherein:

a load connected to said first battery comprises on-vehicle equipment driven by a power source of at least 42V including at least one of a power window, a defroster, a catalytic converter heating device, an electrically actuated air conditioner, and a power steering system; and

a load connected to said second battery comprises on-vehicle equipment driven by a 14 V power source, including a lamp or a control unit.

13. The automotive power source apparatus as set forth in claim 6, wherein said engine is driven when either a key switch is in off state, or a key switch is in on state and an engine is stopped.

14. A power source control apparatus for controlling a power source comprising an inverter coupled to feed power to a motor-generator connected to an engine and to receive power from said motor-generator, a first battery connected to said inverter, a converter that converts output voltage of said first battery into a specified voltage, a second battery connected to said converter, a load connected to said first battery, and a load connected to said second battery;

wherein said control apparatus controls an on-off state of said converter to regulate charging of said second battery through said converter, by either said inverter or said first battery.

15. The power source control apparatus as set forth in claim 14, wherein said control apparatus controls said on-off state of said converter corresponding to remaining capacity of said first battery.

16. The power source control apparatus as set forth in claim 14, wherein said control apparatus controls one of an on-off state of said load connected to said first battery and an on-off state of said converter, corresponding to a remaining capacity of said first battery.

17. The power source control apparatus as set forth in claim 14, wherein said control apparatus controls one of an on-off state of said load connected to said second battery, and an on-off state of said converter, corresponding to remaining capacity of said second battery.

18. The power source control apparatus as set forth in claim 14, wherein said control apparatus outputs a command signal to bring said converter into an off state and outputs a command signal to said inverter for starting said engine to charge said first battery, corresponding to the remaining capacity of said first battery.

19. The power source control apparatus as set forth in claim 14, wherein said control apparatus outputs a command signal to bring said converter into off state, and controls so that power is supplied to said load connected to said second battery.

20. The power source control apparatus as set forth in claim 14, wherein said control apparatus outputs a command signal to keep said converter in an on state until remaining capacity of said first battery reaches a predetermined amount, outputs a command signal to bring said converter into an off state when said remaining capacity of said first battery reaches said predetermined amount, and supplies power to said load connected to said second battery until remaining capacity of said second battery reaches a predetermined amount.