Power conditioning system for fuel cell with 2-stage DC-DC converter

This paper proposes a grid-tied power conditioning system for the fuel cell, which consists of an LLC resonant DC-DC converter and a 3-phase inverter. The LLC resonant converter boosts the fuel cell voltage of 26-48V up to 400V, using the hard-switching boost converter and the high-frequency unregulated LLC resonant converter. The operation of proposed power conditioning system was verified through simulations with PSCAD/EMTDC software. The feasibility of hardware implementation was verified through experimental works with a laboratory prototype, which was built with 1.2kW PEM fuel-cell stack, 1kW high gain step-up converter, and 2kW PWM inverter. The proposed system can be utilized to commercialize a real interconnection system for the fuel-cell power generation.