Fuel cells configured to deliver bi-polar high voltage DC power
A fuel-cell system at 540 VDC for powering an electrical load of a rotorcraft with a first fuel cell and a second fuel cell. Each fuel cell is configured identically and features a positive electrical node and a negative electrical node. Each fuel cell is configured to provide one half of the electrical load of the rotorcraft and one half of the voltage of the electrical load.
1. A fuel-cell system for powering an electrical load of a rotorcraft, comprising:
a first fuel cell having a positive node and a negative node;
a second fuel cell having a positive node and a negative node, the positive node of the second fuel cell being electrically coupled to the negative node of the first fuel cell; and
a contactor coupling the positive node of the first fuel cell to the electrical load and coupling the negative node of the second fuel cell to the electrical load;
wherein each fuel cell is coupled to the electrical load of the rotorcraft without a converter or other power electronics; and
wherein each fuel cell is configured to provide one half of a voltage required by the electrical load.
2. The fuel-cell system of claim 1 , wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell.
3. The fuel-cell system of claim 1 , wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell; and
wherein the contactor is configured to detect conditions with the electrical load.
4. The fuel-cell system of claim 1 , wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell; and
wherein the contactor is configured to detect conditions with at least one of the fuel cells.
5. The fuel-cell system of claim 1 , wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell;
wherein the contactor is configured to detect conditions with the electrical load; and
wherein the contactor is configured to detect conditions with at least one of the fuel cells.
6. The fuel-cell system of claim 1 , wherein the voltage required by the electrical load is 540 VDC.
7. A fuel-cell system for powering an electrical load of a rotorcraft, comprising:
a first fuel cell having;
a positive node; and
a negative node; and
a second fuel cell having;
a positive node; and
a negative node;
wherein the negative node of the first fuel cell is electrically coupled to the positive node of the second fuel cell;
wherein the electrical load is coupled without a converter or other power electronics to the positive node of the first fuel cell and the negative node of the second fuel cell; and
wherein the first fuel cell and the second fuel cell provide similar voltage.
8. The fuel-cell system of claim 7 , further comprising:
a contactor;
wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell.
9. The fuel-cell system of claim 7 , further comprising:
a contactor;
wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell; and
wherein the contactor is configured to detect conditions with the electrical load.
10. The fuel-cell system of claim 7 , further comprising:
a contactor;
wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell; and
wherein the contactor is configured to detect conditions with at least one of the fuel cells.
11. The fuel-cell system of claim 7 , further comprising:
a contactor;
wherein the contactor is configured to electrically isolate the electrical load from the first fuel cell and the second fuel cell;
wherein the contactor is configured to detect conditions with the electrical load; and
wherein the contactor is configured to detect conditions with at least one of the fuel cells.
12. The fuel-cell system of claim 1 , wherein the negative node of the first fuel cell and the positive node of the second fuel cell are electrically coupled to a ground.
13. The fuel-cell system of claim 1 , wherein the voltage supplied by the first fuel cell is +270 VDC and the voltage supplied by the second fuel cell is −270 VDC.
14. The fuel-cell system of claim 7 , wherein the negative node of the first fuel cell and the positive node of the second fuel cell are electrically coupled to a ground.
15. The fuel-cell system of claim 7 , wherein the voltage supplied by the first fuel cell is +270 VDC and the voltage supplied by the second fuel cell is −270 VDC.