Scalable insulated DC/DC converters for safe and efficient coupling of fuel cells, electrolyzers and DC grids

This paper describes scalable insulated DC/DC converters for safe and efficient coupling of fuel cells and electrolyzers with a 380 V single phase respectively +/-380 V split-phase DC grid. Energy storage systems in the MWh range, based on liquid organic hydrogen carriers (LOHC), can be realized this way. An 11 kW insulated fuel cell DC/DC as well as an 11 kW insulated electrolyzer converter, both based on novel universal building blocks, are presented together with efficiency measurements for different operating points. High efficiencies under partial load conditions are achieved by using a modular design approach and phase shedding. The modular power electronic design is described in detail.