Analysis of battery backup and switching controller for a fuel-cell powered automobile

In this paper, we consider the design of a fuel-cell powered automobile that utilizes methane as a source of hydrogen to power a PEM fuel cell. It is shown that when the power demand of the motor goes up suddenly, there is a time lag for generating the necessary hydrogen. A battery backup that provides the necessary power during this time lag is analyzed via an equivalent circuit model. A logic-based switching controller that switches between the fuel cell and the backup battery is designed to meet the power demand. The efficacy of this scheme is tested via simulations on a power profile obtained from a realistic speed profile of a small automobile.