Pressure balanced DC/DC converter for subsea fully electric Remotely Operated Vehicles (eROVs)

In this thesis different solutions will be proposed and analyzed for the design of a DC/DC buck-based converter to be employed in a Work Class fully electric Remotely Operated Vehicle (W-eROV) developed to work under high pressure conditions (around 300bar, 3000m subsea). The Saipem product in which the converter will be employed is called "Hydrone-W", a W-eROV designed to operate in traditional ROV mode or as a subsea resident device tethered to a subsea or surface base and controlled from a remote station. The Hydrone-W can also perform various tasks to support subsea construction, maintenance or emergency operations. At the moment no commercially available solutions can be used, since most of them cannot work in such high pressure conditions handling such high power (200kW). Thereby all the considerations about the converters presented and their design were made from the ground up. In addition to the harsh environment in which it operates, special attention has to be paid to the volume of the converter because of its need to be mounted on the eROV. Moreover, since no specifically dedicated tests under high pressure conditions have been carried out on SiC MOSFETs until now, this thesis presents different testing boards which have been developed.