Energy management method using the IIR filter for PEMFC-supercapacitor hybrid power source

A miniature proton exchange membrane fuel cell (PEMFC) is expected to be applied to small electronic devices such as smartphones. However, PEMFC cannot response quickly against fast load changes of electronic devices. Hybrid power source system using fuel cell (FC) and supercapacitor (SC) with multi-port bidirectional DC-DC converter has been proposed. In this work, the energy management method has been proposed. In this method, the SC voltage in the range of lower frequencies was extracted by using finite impulse response (FIR) low-pass filter (LPF) and determined the reference value for the FC through proportional integral (PI) control method. In this study, infinite impulse response (IIR) filter, which would reduce the number of calculations compared to a FIR filter, was used as LPF. A simplified numerical model was constructed to ensure the system stability. It was confirmed that the system with the IIR filter worked properly.