Focusing on the relevant pros provided by power conversion onboard introduction (e.g. reduction of power system weight/volume), a widespread use of power converters is foreseeable in future MVDC shipboard power systems. For conveniently exploiting the power converters capability in the marine environment, a preliminary investigation about the attainable topologies must be carried out. In this paper the focus is limited to the AC-DC interface power conversion stage. Starting from the analysis of the power devices fully available on the market, four AC-DC interface converters topologies are proposed: a 12-pulse thyristor rectifier, an IGCT based rectifier, a modular multilevel IGBT rectifier and finally an IGBT Dual Active Bridge (DAB) based rectifier. With references to the present standards issues, the survey highlights advantages and disadvantages of the presented topologies providing a preliminary comparison in terms of rough estimation of weights, filtering elements, scalability (both in power and in voltage), power quality performance, galvanic isolation, complexity, etc.
