Near-Optimal Controls of a Fuel Cell Coupled with Reformer using Singular Perturbation methods

A singularly perturbed model is proposed for a system comprised of a PEM Fuel Cell (PEM-FC) with Natural Gas Hydrogen Reformer (NG-HR). This eighteenth order system is decomposed into slow and fast lower order subsystems using singular perturbation techniques that provides tools for separation and order reduction. Then, three different types of controllers, namely an optimal full-order, a near-optimal composite controller based on the slow and the fast subsystems, and a near-optimal reduced-order controller based on the reduced-order model, are designed. The comparison of closedloop responses of these three controllers shows that there are minimal degradations in the performance of the composite and the reduced order controllers.