Design, implementation and experimental validation of a DC-DC resonant converter for PEM fuel cell applications

When designing DC-DC resonant converters (RC) for PEM fuel cell applications some considerations must be fulfilled, such as; an appropriate topology, adequate control structure, accurate selection of the components namely, the power switches, heat sinks and core of each magnetic components and careful design of the HF transformer, resonant circuit and filters. The combination of all of these aspects defines the performance of the converter, hence the importance to be taken on its design. Particularly an accurate design of the RC defines its dynamics and stability. In this context, the paper is focused on the design, implementation and experimental validation of a DC-DC resonant converter for such applications. Once characterized the PEM fuel cell as electrical element of the circuit and defined the topology and control of the resonant converter its operation is analyzed based on second-order differential equation, where each one of the operation modes is treated separately. The constraints imposed by the PEM fuel cell are considered in the selection of the components, followed by the implementation of a 1kW prototype of the RC. The procedure proposed as well as the performance of the RC implemented in terms of dynamics and stability is validated by experimental results.