Generator system utilizing a fuel cell

• US 4,839,574 A
• Filed: 05/06/1988
• Issued: 06/13/1989
• Est. Priority Date: 05/08/1987
• Status: Expired due to Term

• Current Assignee: Fuji Electric Company Limited (Fuji Electric Systems Company Limited)
• Original Assignee: Fuji Electric Company Limited (Fuji Electric Systems Company Limited)
• Inventors: Takabayashi, Yasuhiro
• Primary Examiner(s): Hickey, R. J.
• Application Number:
  US07/191,033
• Time in Patent Office: 403 Days
• Field of Search: 320/2-5, 320/15, 320/39, 320/24, 320/44, 429/23, 429/9
• US Class Current: 320/101
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 2250/405 Cogeneration of heat or hot water
• CPC Class Codes: H01M 8/04589 of fuel cell stacks
• CPC Class Codes: H01M 8/04656 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04753 of fuel cell reactants
• CPC Class Codes: H01M 8/04947 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04953 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/0612 from carbon-containing material
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: Y02B 90/10 Applications of fuel cells in buildings
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

In a generator system having a fuel cell and a battery to which an output current is supplied from the fuel cell, the output current from the fuel cell is controlled in response to the energy charged in the battery, so that the stable supply of the current to the load can be ensured. As the load is increased, the battery discharges to the load, so that the energy charged in the battery is decreased. In this case, the control is carried out to increase the output current from the fuel cell, so that the burden on the battery is decreased.

Claims

1. A method for controlling a generator system having a fuel cell and a battery to which the output current from said fuel cell can be supplied, comprising the steps of:

performing a first adjustment of adjusting the output current delivered from said fuel cell;

performing the second adjustment of adjusting the output current produced in said fuel cell;

storing into a memory means a predetermined relationship between the charged amount of said battery and the control signal for controlling the output current from said fuel cell;

detecting the energy stored in said battery;

looking up said predetermined relationship in relation to the detected signal representative of the energy stored in said battery to form a control signal for controlling the output current from said fuel cell; and

controlling said first and second adjustment in response to said control signal, so that the output current generated by said fuel cell is increased when the energy stored in said battery is decreased.

2. A method as claimed in claim 1, wherein said first adjustment step further includes a step for detecting the current delivered from said fuel cell.

3. A method as claimed in claim 2, wherein said current is detected by means of a Hall current transformer.

4. A method as claimed in claim 1, wherein said second adjustment step is executed by a controller for auxiliary devices.

5. A method as claimed in claim 4, wherein said controller for auxiliary devices comprises an arithmetic unit, a pulse-width modulator and power elements.

6. A method as claimed in claim 5, wherein said arithmetic unit comprises a function generator in the form of a CPU, an operational amplifier and one or more resistors.

7. A generator system having a fuel cell and a battery to which the output current from said fuel cell can be supplied, comprising:

a first adjustment means for adjusting the output current delivered from said fuel cell;

a second adjustment means for adjusting the output current generated in said fuel cell;

memory means for storing therein a predetermined relationship between the energy stored in said battery and a control signal for controlling the output current from said fuel cell;

a detector means for detecting the amount of energy stored in said battery;

means for looking up said predetermined relationship in relation to the detection signal representative of the energy stored in said battery to form a control signal for controlling the output current from said fuel cell; and

a control means for controlling said first and second adjustment means in response to said control signal so that the output current delivered from said fuel cell is increased when the energy stored in said battery is decreased.

8. A generator system as claimed in claim 7, wherein said second adjustment means adjusts the volume of air discharged from an air blower for combustion for supplying air for combustion to said fuel cell.

9. A generator system as claimed in claim 7, wherein said second adjustment means is composed of a controller for auxiliary devices.

10. A generator system as claimed in claim 9, wherein said controller for auxiliary devices comprises an arithmetic unit, a pulse-width modulator and power elements.

11. A generator system as claimed in claim 10, wherein said arithmetic unit comprises a function generator in the form of a CPU, an operational amplifier and one or more resistors.