A novel low-ripple interleaved buck-boost converter with high efficiency and low oscillation for fuel-cell applications

Efficiency and dynamics of DC-DC converters play a major role in proficiency of renewable energy exploitation. This paper presents a novel DC-DC interleaved buck-boost converter for fuel-cell applications. While keeping the same step-up/step-down voltage transfer ratio, the proposed converter exhibits non-pulsating I/O currents using interleave technique. A damping network is also added to improve the inner dynamics of converter. Besides the steady state operation based on state space averaging (SSA) method, design considerations of converter are thoroughly elaborated. MATLAB/SIMULINK environment is used for simulating the steady state operation of proposed converter, and the experimental results are presented, to verify the theoretical expected merits of the converter including high efficiency, non-pulsating I/O currents and low voltage oscillation. Prototype setup of 360 W and 36 V output voltage for a fuel cell with a brand of “FCgen 1020ACS” Ballard Power Systems, Inc was implemented. Experimental results including efficiency and time domain responses in the steady state show impressive benefits of the proposed converter.