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US 9,755,257 B2Granted
Fuel cell system and method for controlling fuel cell system
AssigneeNissan Motor Co., Ltd.
InventorHiromichi Miwa
Life of this patent
Estimating the term…
Abstract
The cooling capacity of a first heat exchanger for cooling a reformed gas introduced into an inlet of a circulation pump is increased as an output of a fuel cell increases. With this configuration, an inlet temperature of the circulation pump is relatively high during low power generation and decreases as the generation power increases, and a volumetric flow rate during high power generation in which a large amount of reformed gas is required can be decreased relatively. As the result, a dynamic range required for the circulation pump can be made small. Furthermore, water condensation in the inlet of the circulation pump can be prevented during low power generation.
Claims12
A fuel cell system, comprising:
- a fuel cell having an anode and a cathode;
- a fuel supply flow passage connecting to an anode inlet of the fuel cell;
- a fuel exhaust flow passage connecting to an anode outlet of the fuel cell;
- a fuel circulation flow passage branched from the fuel cell exhaust flow passage at a first joint portion and jointed to the fuel supply flow passage at a second joint portion;
- a reforming unit installed in the fuel supply flow passage between the second joint portion and the anode inlet of the fuel cell, to generate a reformed gas;
- a circulation pump installed in the fuel supply flow passage between the reforming unit and the anode inlet of the fuel cell;
- and
- a first heat exchange unit installed in the fuel supply flow passage between the reforming unit and the circulation pump, wherein
- the first heat exchange unit is set so that the larger an output power of the fuel cell is, the more a temperature of a fluid supplied to a low temperature side of the first heat exchange unit decreases and the more a capability to cool the reformed gas supplied to the circulation pump increases.
6 more elements
A method for controlling a fuel cell system including
- a fuel cell having an anode and a cathode;
- a fuel supply flow passage connecting to an anode inlet of the fuel cell;
- a fuel exhaust flow passage connecting to an anode outlet of the fuel cell;
- and
- a fuel circulation flow passage branched from the fuel cell exhaust flow passage at a first joint portion and jointed to the fuel supply flow passage at a second joint portion, the method for controlling the fuel cell system, comprising the steps of:
- reforming a fuel by a reforming unit installed in the fuel supply flow passage between the second joint portion and the anode inlet of the fuel cell, to generate a reformed gas;
- circulating the reformed gas by a circulation pump installed in the fuel supply flow passage between the reforming unit and the anode inlet of the fuel cell such that the circulation pump is provided after an outlet of the reforming unit and before the anode inlet, and the reformed gas circulates via the circulation pump;
- and
- cooling the reformed gas supplied to the circulation pump by a first heat exchange unit installed in the fuel supply flow passage between the reforming unit and the circulation pump, wherein
- the first heat exchange unit is set so that the larger an output power of the fuel cell is, the more a temperature of a fluid supplied to a low temperature side of the first heat exchange unit decreases and the more a capability to cool the reformed gas supplied to the circulation pump increases, and
- the temperature of the reformed gas at the inlet of the circulation pump decreases due to the increase of the capability to cool the reformed gas supplied to the circulation pump.
8 more elements
A method for controlling a fuel cell system including
- a fuel cell having an anode and a cathode;
- a fuel supply flow passage connecting to an anode inlet of the fuel cell;
- a fuel exhaust flow passage connecting to an anode outlet of the fuel cell;
- and
- a fuel circulation flow passage branched from the fuel cell exhaust flow passage at a first joint portion and jointed to the fuel supply flow passage at a second joint portion,
- the method for controlling the fuel cell system, comprising the steps of:
- reforming a fuel by a reforming unit installed in the fuel supply flow passage between the second joint portion and the anode inlet of the fuel cell, to generate a reformed gas;
- circulating the reformed gas by a circulation pump installed in the fuel supply flow passage between the reforming unit and the anode inlet of the fuel cell;
- and
- cooling the reformed gas supplied to the circulation pump by a first heat exchange unit installed in the fuel supply flow passage between the reforming unit and the circulation pump, wherein
- the first heat exchange unit is set so that the larger an output power of the fuel cell is, the more a temperature of a fluid supplied to a low temperature side of the first heat exchange unit decreases and the more a capability to cool the reformed gas supplied to the circulation pump increases.
8 more elements
Dependencies are inferred from the claim text.