Fuel cell vehicle and control method thereof

• US 20060021812A1
• Filed: 08/01/2005
• Published: 02/02/2006
• Est. Priority Date: 08/02/2004
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Saeki, Hibiki, Aoyagi, Satoshi
• Granted Patent: US 7,722,970 B2
• Time in Patent Office: Days
• US Class Current: 180/65.310
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60L 58/33 by cooling
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: B60L 7/14 for vehicles propelled by ac motors
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 2250/20 Fuel cells in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 2250/407 Combination of fuel cells with mechanical energy generators
• CPC Class Codes: H01M 8/04298 Processes for controlling fuel cells or fuel cell systems
• CPC Class Codes: H01M 8/0488 of fuel cell stacks
• CPC Class Codes: H01M 8/0491 of fuel cell stacks
• CPC Class Codes: H01M 8/0494 of fuel cell stacks
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• 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 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A fuel cell vehicle includes a fuel cell, a rotating load, a energy storage, a contactor, a DC-DC converter, and a control unit. When regeneration by the energy storage is performed, the DC-DC converter connected to the energy storage is placed in a direct connection mode for directly charging regeneration electrical energy from a motor of the rotating load to the energy storage.

Claims

1. A fuel cell vehicle comprising:

a fuel cell capable of generating electrical energy by electrochemical reaction of a reactant gas and outputting the electrical energy to a rotating load;

a rechargeable energy storage;

a switching mechanism capable of electrically connecting said fuel cell to said rotating load and said energy storage, and electrically disconnecting said fuel cell from said rotating load and said energy storage;

a DC-DC converter connected to said energy storage;

a regeneration determination mechanism for determining whether regeneration by said energy storage is performed or not; and

a direct connection control mechanism for placing said DC-DC converter in a direct connection mode for directly charging regeneration electrical energy from said rotating load to said energy storage if it is determined that the regeneration is performed.

2. A fuel cell vehicle according to claim 1, further comprising a direct connection preparation mechanism for performing step-down voltage control of said DC-DC converter before said DC-DC converter is placed in the direct connection mode.

3. A fuel cell vehicle according to claim 1, further comprising a disconnection control mechanism for electrically disconnecting said fuel cell from said energy storage by said switching mechanism if it is determined that the regeneration is performed.

4. A fuel cell vehicle according to claim 3, further comprising a current control mechanism for controlling the fuel cell current to a reference value or less before electrically disconnecting said fuel cell from said energy storage by said switching mechanism.

5. A fuel cell vehicle according to claim 1, further comprising a step-up voltage control mechanism for performing step-up voltage control of said DC-DC converter after regeneration by said energy storage is finished, and a connection control mechanism for allowing electrical energy from said fuel cell to be outputted to said rotating load by said switching mechanism.

6. A method of controlling a fuel cell vehicle comprising a fuel cell capable of generating electrical energy by electrochemical reaction of a reactant gas and outputting the electrical energy to a rotating load, a rechargeable energy storage, a switching mechanism capable of electrically connecting said fuel cell to said rotating load and said energy storage, and electrically disconnecting said fuel cell from said rotating load and said energy storage, and a DC-DC converter connected to said energy storage, said method comprising the steps of:

determining whether regeneration by said energy storage is performed or not; and

placing said DC-DC converter in a direct connection mode for directly charging regeneration electrical energy from said rotating load to said energy storage if it is determined that the regeneration is performed.

7. A control method according to claim 6, further comprising the step of performing step-down voltage control of said DC-DC converter before said DC-DC converter is placed in the direct connection mode.

8. A control method according to claim 6, further comprising the step of electrically disconnecting said fuel cell from said energy storage by said switching mechanism if it is determined that the regeneration is performed.

9. A control method according to claim 8, further comprising the step of controlling the fuel cell current to a reference value or less before electrically disconnecting said fuel cell from said energy storage by said switching mechanism.

10. A control method according to claim 6, further comprising the steps of performing step-up voltage control of said DC-DC converter after regeneration by the energy storage is finished, and allowing electrical energy from said fuel cell to be outputted to said rotating load by said switching mechanism.