Analysis of an integrated reformer-membrane-fuel cell system with battery backup and switching controller : Start-up case

Due to several stringent challenges and constraints faced in direct on-board storage of hydrogen in fuel cell vehicles, appreciable efforts are in progress to prevent direct storage of hydrogen. Directly storing hydrocarbons rich in hydrogen and suitably reforming them in-situ using available reforming techniques could be a possible option to overcome this challenge. A detailed overview of the mathematical modeling and analysis of the integrated reformer membrane fuel cell system was already discussed in an earlier paper. It was shown that at start-up of the plant and during frequent fluctuations in the power demand, requirement of an auxiliary power source like battery/super-capacitor is crucial for a delay free response to the power demand. In this study, an equivalent circuit model of a battery backup system is analyzed along with a switching controller that switches between battery and fuel cell based on some energy management policy. The mathematical model of the system is simulated, considering case study of start-up of the integrated system powering a fuel cell vehicle with battery backup, assuming an idealized driving power profile.