Automobile and power supply system therefor

• US 6,426,608 B2
• Filed: 06/19/2001
• Issued: 07/30/2002
• Est. Priority Date: 06/19/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Masaki, Ryoso, Morooka, Yasuo, Amano, Masahiko
• Primary Examiner(s): Han, Jessica
• Assistant Examiner(s): LUK, LAWRENCE W
• Application Number:
  US09/883,350
• Publication Number:
  US 20010052760A1
• Time in Patent Office: 406 Days
• Field of Search: 320/163, 320/162, 320/110, 307/24, 307/46, 307/66, 307/75, 307/76
• US Class Current: 320/163
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2250/26 by pedal actuation
• CPC Class Codes: B60L 2260/26 Transition between different drive modes
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 58/14 Preventing excessive discharging
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/20 : having different nominal voltages
• CPC Class Codes: B60L 58/21 : having the same nominal voltage
• CPC Class Codes: B60L 7/14 : for vehicles propelled by ac motors
• CPC Class Codes: B60W 10/26 : for electrical energy, e.g. batteries or capacitors
• 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: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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
• CPC Class Codes: Y10S 903/903 : having energy storing means, e.g. battery, capacitor

Abstract

In an automobile power supply where plural voltages can be supplied, a plurality of batteries and a DC/DC converter are assumed to be unnecessary, and it is possible to operate even when the controller breaks down.

High-voltage terminal 11 and low-voltage terminal 12 are provided in battery 6. High-voltage FET 4 for controlling the power supply in one direction from high-voltage terminal 11 to inverter 3 is connected between inverter 3 and high-voltage terminal 11. Low-voltage FET 5 for controlling the power supply in one direction from inverter 3 to low-voltage terminal 12 between inverter 3 and low-voltage terminal 12 is connected.

Claims

1. A power-supply unit for an automobile comprising:

a battery having a high-voltage terminal and a low-voltage terminal;

a converter for converting AC power into DC power;

a first switching element for controlling the power supply in one direction from the high-voltage terminal of the battery to the converter; and

a second switching element for controlling the power supply in one direction from the converter to the low-voltage terminal of the battery.

2. The power-supply unit for an automobile according to claim 1, wherein the switching element which forms said converter and said first and said second switching element are integrated.

3. The power-supply unit for an automobile according to claim 1,

wherein said first and said second switching element comprise a field effect transistor (FET) and diodes connected oppositely to each other, and

wherein when the electric current is about to flow from the source side of said first or second switching element to its drain side, the gate of the switching element is turned on.

4. The power-supply unit for an automobile according to claim 1,

wherein the voltage of the DC side of said converter is controlled according to the state of said first and said second switching element.

5. The power-supply unit for an automobile according to claim 1,

wherein when at least one of said first and the second switching elements cannot be controlled, the voltage of the DC side of said converter is controlled according to the direction of the electric power of said converter.

6. The power-supply unit for an automobile according to claim 1,

wherein said battery comprises a plurality of battery blocks connected in series.

7. The power-supply unit for an automobile according to claim 1, further comprising a charging rate measuring means for detecting the charging rate of the high-voltage terminal side of said battery and the charging rate of the low-voltage terminal side, respectively,

wherein said first and said second switching element are controlled according to the charging rate detected by said charging rate measuring means.

8. The power-supply unit for an automobile according to claim 1, wherein when the voltage of the DC side of said converter is controlled according to the target voltage value at the other terminal of said battery, the correction is performed according to the voltage detection value of another terminal of said battery.

9. The automobile according to claim 1, wherein said first and said second switching element are a first and a second field effect transistor, respectively.

10. An automobile including:

a motor/generator;

an inverter for driving said motor/generator;

a battery connected to said inverter through the terminals at a plurality of different voltages;

a first switching element provided between said inverter and a first fixed terminal of the terminals at a plurality of different voltages of said battery;

a first rectifying device connected in parallel with the intermittence-switching means provided in said first switching element, for throwing more electric currents in the direction of said first terminal from said inverter;

a second switching element provided between said inverter and a second terminal at a voltage lower than that of said the first terminal of the terminals of a plurality of different voltages of said battery;

a second rectifying device connected in parallel with the intermittence-switching means provided in said second switching element, for throwing more electric currents in the direction of said second terminal from said inverter; and

a battery control unit for turning on/off said first and said second switching element according to the state of the charge of said battery.