When marine vessels connect to shore power supplies, a galvanically isolated AC/AC power converter is typically used to convert the shore supply voltage and frequency to that required by the vessel. Commonly in industry, isolation is provided by a mains frequency transformer. Therefore, the converter size and weight are significant. Within a marine environment, this is very disadvantageous. However, through high-frequency converter operation, advances in terms of reduced size and weight can be realised.

To meet required marine vessel specifications, it is shown in this thesis that a high-frequency AC/AC converter is best implemented using a DC-link converter, as the AC input is rectified and regulated, before inversion back to AC. This thesis is concerned with the input stage of an AC/AC converter, comprising the AC/DC converter used to form the DC-link. The proposed AC/DC converter is a bridgeless isolated type, which combines high-frequency isolation, active PFC, and AC/DC conversion into a single stage using a series resonant circuit. A research gap is identified in the design of the resonant circuit necessary for this converter and thus, a design procedure is developed. This is significant, as the resonant circuit plays a crucial role in the converter operation and the ratings needed for its components. The design procedure is verified through simulation using PLECS, and the development of a prototype unit implemented with digital control and silicon carbide switching devices.