Method for controlling fuel cell stack current
AssigneeFord Global Technologies, LLC
InventorsJack Xu, Ramakrishna Raju, Matt DeDona, Raymond Spiteri
Life of this patent
Estimating the term…
Abstract
The level of electrical current produced by a fuel cell during rapid changes in the power demanded by a load, is clamped to the fuel cell's maximum rated current value in order to avoid damage to the fuel cell. When the current supplied to the load by the fuel cell overshoots the maximum rated current value, the fuel cell current is immediately reduced by increasing the fuel cell voltage.
Claims20
A method of limiting fuel cell current during transient changes in power demanded by a load, comprising the steps of:
- sensing when the level of current produced by the fuel cell exceeds a preselected value as a result of a transient change in the power demanded by the load;
- and,
- increasing the terminal voltage of the fuel cell to reduce the current to below the preselected value when the sensed current exceeds the preselected value.
A method for controlling power supplied to an electric vehicle traction motor from a fuel cell and an electrical energy storage system, comprising the steps of:
- sensing when the current supplied to the motor by the fuel cell overshoots the maximum rated fuel cell current in response to a transient power demand;
- reducing the fuel cell current in response to the current overshoot by increasing the fuel cell voltage;
- and,
- increasing the power requested to be supplied by the electrical energy storage system when the fuel cell current is reduced.
A method of clamping the level of electrical current produced by a fuel cell used to power an electric vehicle traction motor during rapid changes in the power demanded by the motor, comprising the steps of:
- sensing when the current supplied to the motor by the fuel cell overshoots the maximum rated fuel cell current in response to a rapid power demand change;
- reducing the fuel cell current in response to the current overshoot by increasing the fuel cell voltage;
- and,
- providing power to the motor from an electrical energy storage system on-board the vehicle when the fuel cell current is reduced following a current overshoot.
Dependencies are inferred from the claim text.