This study is focused on studying a resonant current converter for the electrical supply of dielectric barrier discharge devices. To understand the impact of parasitic capacitances and incorporate them into the design of an optimised power supply, this approach theoretically analyses a boost-based resonant converter, considering switch capacitance and analysing the impact of the transformer turns ratio on the system's electrical efficiency. The theoretical loss analysis shows a considerable variation in efficiency for different transformer turns ratios (between 38 and 90%). At low turns ratios, most of the losses are caused by switching, whereas at high turns ratios, the conduction losses outweigh the switching losses. The impact of the transformer stray capacitance is analysed via simulation and the optimised converter is used for the experimental validation of the theoretical study.