Electrolyser in H2 self-producing systems connected to DC link with dedicated phase shift converter

In this paper the converter requirements for an optimum control of an electrolyser linked with a DC bus are analyzed and discussed. The hydrogen generating device is part of a complex system constituted by a supplying photovoltaic plant, the grid and a fuel cell battery. The characterization in several operative conditions of an actual industrial electrolyser is carried out in order to design and optimize the DC/DC converter. A dedicated zero voltage switching DC/DC converter is presented and simulated inside the context of the distributed energy production and storage system. The proposed supplying converter gives a stable output voltage and high circuit efficiency in all the proposed simulated scenarios. The adopted DC/DC converter is realized in a full-bridge topology with phase-shift PWM technique in order to achieve zero voltage switching for the power switches and to regulate the output voltage. Furthermore, in order to increase the converter efficiency at the transformer secondary side, a current doubler rectifier is implemented.