Supply of electric power using fuel cell and chargeable/dischargeable storage

• US 20030106726A1
• Filed: 11/14/2002
• Published: 06/12/2003
• Est. Priority Date: 05/15/2000
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Yoshii, Kinya
• Granted Patent: US 7,301,302 B2
• Time in Patent Office: Days
• US Class Current: 180/65.1
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/32 characterised by the fuel cells
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/62 Vehicle position
• CPC Class Codes: B60L 2240/642 Slope of road
• CPC Class Codes: B60L 2250/28 Accelerator pedal thresholds
• 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: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/28 including control of fuel cells
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/103 Accelerator thresholds, e.g. kickdown
• CPC Class Codes: B60W 2540/106 Rate of change
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 50/0097 : Predicting future conditions
• 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 8/04626 : of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/0494 : of fuel cell stacks
• CPC Class Codes: H01M 8/04947 : of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04992 : characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence
• CPC Class Codes: H02P 6/34 : Modelling or simulation for control purposes
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells
• 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 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells
• CPC Class Codes: Y10S 903/908 : Fuel cell

Abstract

Intended to utilize a fuel cell efficiently while ensuring good output responsiveness by the fuel cell.

In a vehicle having a motor as the drive power source, a fuel cell and battery are on board as the power source for the motor. A target output value for the fuel cell is set within a range such that fuel cell output can track change in power demand. The battery is charged/discharged so as to compensate for delay in fuel cell output relative to power demand. By setting a higher target output value the lower the remaining charge in the battery, the fuel cell can be utilized efficiently while ensuring good output responsiveness.

Claims

1. Power supply device that supplies power using a fuel cell and rechargeable storage portion as the power source, said power supply device comprising:

a power demand, input portion for progressively inputting the power demand placed on said power supply portion;

a memory portion that holds in memory a relationship of said power demand to a target output value for output by said fuel cell, the relationship defined by a range such that the slope of change of said target output value relative to change in power demand does not exceed a certain predetermined value determined on the basis of output responsiveness of said fuel cell;

a target output value setting portion that refers to said memory portion to set said target output value with reference to said power demand;

a fuel cell control portion for controlling operation of said fuel cell with reference to said target output value; and

a charge/discharge portion for charging/discharging said storage portion on the basis of said power demand and said target output value.

2. Power supply device according to claim 1 wherein said charge/discharge portion performs control to compensate for difference between said power demand and power suppliable by said fuel cell.

3. Power supply device according to claim 2 wherein said relationship is set such that in a first predetermined zone wherein said power demand is low, said target output value is greater that said power demand.

4. Power supply device according to claim 2 wherein said relationship is set such that in a second predetermined zone wherein said power demand is high, said target output value is lower than said power demand.

5. Power supply device according to claim 1 further comprising a sensor portion for sensing remaining charge in said storage portion, wherein

said relationship is set for each said remaining charge, and

said target output value setting portion sets said target output value in consideration of said remaining charge.

6. Power supply device according to claim 5 wherein said relationship is such that said target output value is larger the smaller said remaining charge.

7. Power supply device that supplies power using a fuel cell and rechargeable storage portion as the power source, said power supply device comprising:

a fuel cell control portion for controlling operation of said fuel cell with reference to a predetermined target output value;

a charge/discharge portion for charging/discharging said storage portion to compensate for difference between said power demand and power outputtable by said fuel cell;

a rate of change sensing portion for sensing the rate of change of said power demand; and

a target output value setting portion for modifying said target output value with reference to said power demand when the absolute value of said rate of change exceeds a predetermined value.

8. Power supply device according to claim 7 further comprising a sensor portion for sensing remaining charge of said storage portion;

and

a target output value correcting portion for correcting said target output value with reference to said remaining charge.

9. Power supply device that supplies power using a fuel cell and rechargeable storage portion as the power source, said power supply device comprising:

a power demand input portion for progressively inputting power demand;

a power demand estimating portion for estimating future power demand after a predetermined period of time;

a target output value setting portion for setting a target output value for output by said fuel cell at the current point in time, based on said future power demand, current power demand and output responsiveness of said fuel cell;

a fuel cell control portion for controlling operation of said fuel cell with reference to said target output value; and

a charge/discharge portion for charging/discharging said storage portion so as to compensate for difference between said current power demand and power outputtable by said fuel cell.

10. Power supply device according to claim 9 wherein said target output value setting portion increases said target output value in advance in conjunction with an increase in said future power demand.

11. Power supply device according to claim 9 wherein said target output value setting portion decreases said target output value in advance in conjunction with a decrease in said future power demand.

12. Power supply device according to claim 9 further comprising:

a sensor portion for sensing remaining charge of said storage portion; and

a target output value correcting portion for correcting said target output value with reference to change in said remaining charge.

13. Power supply device according to claim 9 further comprising a load information memory portion having pre-stored in memory load information that indicates future operating status of a load supplied with power by the power supply device, wherein

said load information memory portion estimates said future power demand on the basis of said load information.

14. Method for controlling a power supply device equipped with a fuel cell and rechargeable storage portion, said method comprising:

(a) a step of progressively inputting power demand;

(b) a step of referring to a memory portion having stored in memory a relationship of said power demand to a target output value for output by said fuel cell and setting a target output value with reference to said power demand;

(c) a step of controlling operation of said fuel cell with reference to said target output value; and

(d) a step of charging/discharging said storage portion on the basis of said power demand and said target output value;

wherein in said step (b) said relationship is established within a range such that the slope of change in said target output value relative to change in said power demand does not exceed a predetermined value established on the basis of output responsiveness of said fuel cell.

15. Method for controlling a power supply device equipped with a fuel cell and rechargeable storage portion, said method comprising:

(a) a step of setting a target output value for output by said fuel cell with reference to power demand under a predetermined timing; and

(b) a step of controlling operation of said fuel cell and said storage portion with reference to said target output value,

wherein said predetermined timing in said step (a) is timing at which rate of change of said power demand exceeds a predetermined value.

16. Method for controlling a power supply device equipped with a fuel cell and rechargeable storage portion, said method comprising:

(a) a step of progressively inputting power demand;

(b) a step of estimating future power demand after a predetermined period of time;

(c) a step of setting a target output value for output by said fuel cell at the current time, on the basis of said future power demand, current power demand and output responsiveness of said fuel cell;

(d) a step of controlling operation of said fuel cell with reference to said target output value; and

(e) a step of charging/discharging said storage portion so as to compensate for difference between said current power demand and power outputtable by said fuel cell.

17. Drive power output device comprising:

a power supply device that supplies power using a fuel cell and rechargeable storage portion as the power source; and

a motor driven by power supplied by said power supply device,

wherein said drive power output device is characterized in that said power supply device comprises;

a power demand input portion for progressively inputting the power demand placed on said power supply portion;

a memory portion that holds in memory a relationship of said power demand to a target output value for output by said fuel cell, the relationship defined by a range such that the slope of change of said target output value relative to change in power demand does not exceed a certain predetermined value determined on the basis of output responsiveness of said fuel cell;

a target output value setting portion that refers to said memory portion to set said target output value with reference to said power demand;

a fuel cell control portion for controlling operation of said fuel cell with reference to said target output value; and

a charge/discharge portion for charging/discharging said storage portion on the basis of said power demand and said target output value.

18. Drive power output device according to claim 17 further comprising:

an engine driven by combustion of fuel; and

control means for driving at least said motor or said engine, or both, to output drive power.

19. Vehicle comprising a power supply device that supplies power using a fuel cell and rechargeable storage portion as the power source;

and

a motor for outputting drive power by means of power supplied by said power supply device,

wherein said vehicle is characterized in that said power supply device comprises;

a power demand input portion for progressively inputting power demand with reference to the degree of acceleration of said vehicle;

a memory portion that holds in memory a relationship of said power demand to a target output value for output by said fuel cell, the relationship defined by a range such that the slope of change of said target output value relative to change in power demand does not exceed a certain predetermined value determined on the basis of output responsiveness of said fuel cell;

a target output value setting portion that refers to said memory portion to set said target output value with reference to said power demand;

a fuel cell control portion for controlling operation of said fuel cell with reference to said target output value; and

a charge/discharge portion for charging/discharging said storage portion on the basis of said power demand and said target output value.

20. Vehicle comprising a power supply device that supplies power using a fuel cell and rechargeable storage portion as the power source;

and

a motor for outputting drive power by means of power supplied by said power supply device,

wherein said vehicle is characterized in that said power supply device comprises;

a power demand input portion for progressively inputting power demand;

a power demand estimating portion for estimating future power demand after a predetermined period of time;

a target output value setting portion for setting a target output value for output by said fuel cell at the current point in time, based on said future power demand, current power demand and output responsiveness of said fuel cell;

a fuel cell control portion for controlling operation of said fuel cell with reference to said target output value; and

a charge/discharge portion for charging/discharging said storage portion so as to compensate for difference between said current power demand and power outputtable by said fuel cell.

21. Vehicle according to claim 20 comprising:

a route information memory portion having pre-stored in memory information for a future route of travel of said vehicle;

wherein said power demand estimating portion estimates said future power demand on the basis of said route information.