Design of a Programmable Power Supply to study the performance of an alkaline electrolyser under different operating conditions

The combination of electrolytic hydrogen production systems with renewable energy sources is arousing considerable interest due to the possibility of obtaining a clean and inexhaustible fuel supply. In turn, electrolysers can play an important role by supporting the operation and energy management of power grids, microgrids and stand-alone systems. In order to optimally integrate electrolysers into any of these scenarios, it is first essential to have a thorough knowledge of their operating characteristics, in stationary and dynamic conditions, with regard to electrical performance, hydrogen production, efficiency, etc. Consequently, this paper presents the design, development and implementation of a Programmable Power Supply (PPS) that is capable of supplying an electrical current having a wide range of amplitudes and variability. This PPS is used to study and analyse a 1 Nm³/h alkaline electrolyser under different operating conditions. Specifically, this work presents the stationary electrical characterisation of the electrolyser, an analysis of the real production of hydrogen and a study of the influence of harmonics on the electrolyser power consumption.