Development of Power Interface With FPGA-Based Adaptive Control for PEM-FC System

This paper presents the development of a power interface for a fuel cell (FC) system supplying an ac load. The proposed system comprises a two stages conditioning system, including a switched capacitor dc-dc boost converter and a full bridge insulated-gate bipolar transistor (IGBT) single-phase inverter (dc-ac converter). A fully digital control structure is proposed to manage both power converters using the same control device. The control strategy takes advantage of the parallelism of the field programmable gate arrays (FPGA) technology to share in real-time the controller´s information addressing the common problem of low-frequency ripple of FC current when supplying ac loads. The control system has been implemented and evaluated by co-simulation, and by experimentation with a proton exchange membrane fuel cell (PEM-FC) system. The results show that the proposed system allows a safe operation of the FC by limiting the current ripple under 3%. These results also confirm that the transient response of the conversion system permits to correctly supply the ac load.