Fuel Cell Power Systems and Applications

Fuel cell power systems offer a unique combination of high efficiency, wide size range, modularity, and compatibility with cogeneration. The development of complete energy systems that realize the benefits offered by fuel cell technology requires a basic understanding of fuel cell system components as well as the associated power electronics for different applications. This paper explains the basic characteristics of a fuel cell system, describes the different types of fuel cells and their current state of development, and discusses the potential application of these systems to transportation and stationary power. Particular emphasis is given to the electrical characteristics of the fuel cell, which is a relatively stiff power source. Power electronic systems are essential for making the fuel cell electrical output compatible with most loads. Options for dc-dc and dc-ac power conversion circuits are given with a discussion of the distinct features of each circuit that can be used for system planning purposes. The interaction between a fuel cell and a single-phase ac inverter load is highlighted because of the widespread applicability of this particular combination.