FUEL CELL SYSTEM

• US 20100316921A1
• Filed: 10/29/2008
• Published: 12/16/2010
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yoshida, Michio, Umayahara, Kenji
• Granted Patent: US 8,445,153 B2
• Time in Patent Office: Days
• US Class Current: 429/432
• CPC Class Codes: B60L 58/30 for monitoring or controlling fuel cells
• CPC Class Codes: B60L 58/40 for controlling a combination of batteries and fuel cells
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• 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 8/04228 during shut-down
• CPC Class Codes: H01M 8/04559 of fuel cell stacks
• CPC Class Codes: H01M 8/04589 of fuel cell stacks
• CPC Class Codes: H01M 8/04619 of fuel cell stacks
• CPC Class Codes: H01M 8/0488 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 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A fuel cell system capable of providing a suitable power distribution is provided. A fuel cell system includes: a fuel cell that generates electric power through an electrochemical reaction between a fuel gas and an oxidant gas; a motor that can be driven upon the supply of electric power and can generate regenerative power; a power storage unit which can be charged with power generated from the fuel cell and regenerative power of the motor and can discharge charge power to the motor; an auxiliary apparatus used for operating at least the fuel cell; and a control unit that controls a power distribution between the above components. The control unit determines the power distribution using a power generation command value based on power required to be generated during a normal operation, while the control unit determines the power distribution using a power generation measured value of the fuel cell instead of the power generation command value during a high-potential prevention control that avoids a voltage of the fuel cell becoming equal to or higher than a predetermined high-potential prevention voltage threshold lower than an open circuit voltage of the fuel cell.

Claims

1. A fuel cell system comprising:

a fuel cell that generates electric power through an electrochemical reaction between a fuel gas and an oxidant gas;

a motor that can be driven upon a supply of electric power and can generate regenerative power;

a power storage unit which is connected in parallel with the fuel cell with respect to the motor and which can be charged with power generated from the fuel cell and regenerative power of the motor and can discharge charge power to the motor;

an auxiliary apparatus that is used for operating at least the fuel cell; and

a control unit that controls a power distribution between the fuel cell, the power storage unit, the motor and the auxiliary apparatus, wherein

the control unit determines the power distribution using a power generation command value based on power required to be generated during a normal operation, while the control unit determines the power distribution using a power generation measured value of the fuel cell instead of the power generation command value during a high-potential prevention control that avoids a voltage of the fuel cell becoming equal to or higher than a predetermined high-potential prevention voltage threshold lower than an open circuit voltage of the fuel cell.

2. The fuel cell system according to claim 1, wherein, when the control unit carries out the high-potential prevention control while operation of the fuel cell is stopped, the control unit determines the power distribution using a power generation measured value of the fuel cell instead of the power generation command value.

3. The fuel cell system according to claim 1, wherein, when the control unit carries out the high-potential prevention control while the power generation command value is zero, the control unit determines the power distribution using a power generation measured value of the fuel cell instead of the power generation command value.