Canadian Patents Database

Claims page

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Patent Document Number: 2704362

(54) English Title: FUEL CELL SYSTEM WITH LOW-EFFICIENCY OPERATION POINT

(54) French Title: PILE A COMBUSTIBLE A POINT DE FONCTIONNEMENT A BAS RENDEMENT

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Claims:

Note: Claims are shown in the official language in which they were submitted.


What is claimed is:

1. A fuel cell system comprising:
a fuel cell which generates a power by use of a fuel gas and an oxidizing
gas;
inhibition means for inhibiting supply of the oxidizing gas in a case where
predetermined conditions are satisfied; and
a control means comprising:
first determination means for determining a target power of the fuel
cell at a time when the supply of the oxidizing gas is inhibited;
second determination means for determining a target current based
on the target power and an actually measured voltage of the fuel cell; and
third determination means for feeding back a deviation between the
target current and an actually measured current of the fuel cell to change the

actually measured voltage of the fuel cell to a voltage of a low-efficiency
operation
point.

2. The fuel cell system according to claim 1, wherein the control means
stops the supply of the oxidizing gas in a case where an output voltage of the
fuel
cell is lowered from the vicinity of an opened circuit voltage to the voltage
at the
low-efficiency operation point, and
the first determination means determines the target power of the fuel cell
at a time when the supply of the oxidizing gas is stopped.
3. The fuel cell system according to claim 1 or 2, wherein the control means
increases the supply of the oxidizing gas when the actually measured output
voltage of the fuel cell has been lowered to the voltage at the low-efficiency

operation point in order to operate the fuel cell at the low-efficiency
operation point
while providing the determined target power.
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