Abstract: A subsea variable speed drive apparatus comprising a pressure resistant container (90) comprising a curved wall section having a curved, internal surface (90a); and a variable speed drive comprising at least one power electronics module (50) arranged inside the container and held at a predetermined ambient pressure. The at least one power electronics module is mounted on a heatsink (40) which is mounted on the internal surface, the heatsink comprising a curved surface (40b) contacting the internal surface and having a radius of curvature corresponding to the radius of curvature of the internal surface. A subsea hydrocarbon fluid pumping system comprising such subsea variable speed drive apparatuses and a related method are also disclosed.

Abstract: The invention provides a system for subsea pressure booster HV (high voltage), MV (medium voltage) and LV (low voltage) power supply and distribution. The system is distinguished in that the system consists of, essentially consists of or comprises: a supply cable without a connected variable speed drive/variable frequency drive (VSD, VFD); at least one subsea pressure booster, and; one subsea direct online switch (SDOS) for each subsea pressure booster, wherein the supply cable at a source end is coupled to an AC power source at a topside, onshore or subsea location, wherein the supply cable at a pressure booster end is coupled directly or via a distribution device to at least one subsea direct online switch, SDOS, wherein each SDOS is coupled to one subsea pressure booster. Method of operation and use of the system.

Abstract: A subsea variable speed drive apparatus comprising a pressure resistant container (90) comprising a curved will section having a curved, internal surface (90a); and a variable speed drive comprising at least one power electronics module (50) arranged inside the container and held at a predetermined ambient pressure. The at least one power electronics module is mounted on a heatsink (40) which is mounted on the internal surface, the heatsink comprising a curved surface (40b) contacting the internal surface and having a radius of curvature corresponding to the radius of curvature of the internal surface. A subsea hydrocarbon fluid pumping system comprising such subsea variable speed drive apparatuses and a related method are also disclosed.

Abstract: A subsea AC power supply device comprises a subsea transformer, having a primary winding arranged to be connected to a topside AC power supply via a subsea power supply cable, and a subsea shunt reactor, connected in parallel with the primary winding of the subsea transformer. The subsea transformer and the subsea shunt reactor are arranged within a common subsea watertight housing. A subsea AC power supply system comprises a topside AC power supply, a subsea power supply cable connected to the topside AC power supply, and a subsea AC power supply device connected to the subsea power supply cable.

Abstract: A subsea power distribution device and system. The subsea power distribution device includes a first watertight housing accommodating at least one transformer having a primary winding and at least one secondary winding, input terminals electrically connected to the primary winding and arranged to be connected to a remote power supply, an output terminal electrically connected to the at least one secondary winding, and switches located within the first watertight housing and arranged to open and close the connections between each secondary winding and a corresponding output terminal. Each output terminal is further connected to an overcurrent breaking device which is further arranged to be connected to a subsea power consuming device. The overcurrent breaking device is arranged in a second watertight housing separate from the first watertight housing and is filled with insulating liquid.

Abstract: A subsea power distribution device and system. The subsea power distribution device comprises a watertight housing accommodating at least one transformer, the transformer having a primary winding and a plurality of secondary windings; input terminals, electrically connected to the primary winding and arranged to be connected to a remote power supply; output terminals, electrically connected to the secondary windings and arranged to be connected to subsea power consuming devices. The switches are arranged to break the connections between each secondary winding and a corresponding output terminal, and the switches are arranged within the watertight housing.

Abstract: A subsea AC power supply device comprises a subsea transformer, having a primary winding arranged to be connected to a topside AC power supply via a subsea power supply cable, and a subsea shunt reactor, connected in parallel with the primary winding of the subsea transformer. The subsea transformer and the subsea shunt reactor are arranged within a common subsea watertight housing. A subsea AC power supply system comprises a topside AC power supply, a subsea power supply cable connected to the topside AC power supply, and a subsea AC power supply device connected to the subsea power supply cable.

Abstract: It is described a switching device comprising a semiconductor switching unit; a contactor electrically coupled in series with the semiconductor switching unit; and a controller being configured for activating an electrically isolating state of the switching device and/or activating an electrically conducting state of the switching device based on a command signal or based on a comparison of a measured value and predetermined activation condition.

Abstract: A subsea power distribution device and system. The subsea power distribution device includes a first watertight housing accommodating at least one transformer, having a primary winding and at least one secondary winding, input terminals electrically connected to the primary winding and arranged to be connected to a remote power supply, an output terminals electrically connected to the at least one secondary winding, and switches located within the first watertight housing and arranged to open and close the connections between each secondary winding and a corresponding output terminal. Each output terminal is further connected to an overcurrent breaking device which is further arranged to be connected to a subsea power consuming device. The overcurrent breaking device is arranged in a second watertight housing separate from the first watertight housing and is filled with insulating liquid.

Abstract: A subsea transformer that includes a transformer and a transformer tank adapted to accommodate the transformer is provided. The transformer tank has an opening that is sized so as to enable insertion of the transformer into the transformer tank through the opening. A closing plate is adapted to close the opening of the transformer tank. At least one component having a double barrier against ingress of an ambient medium surrounding the subsea transformer when installed subsea is mounted to the closing plate.

Abstract: A subsea power distribution device and system. The subsea power distribution device comprises a watertight housing accommodating at least one transformer, the transformer having a primary winding and a plurality of secondary windings; input terminals, electrically connected to the primary winding and arranged to be connected to a remote power supply; output terminals, electrically connected to the secondary windings and arranged to be connected to subsea power consuming devices. The switches are arranged to break the connections between each secondary winding and a corresponding output terminal, and the switches are arranged within the watertight housing.

Abstract: A subsea transformer enclosure is provided. A transformer chamber of the subsea transformer enclosure is adapted to receive a transformer. A pressure compensation device is mounted to the transformer chamber and is adapted to provide pressure balancing between a dielectric liquid in the transformer chamber and an ambient medium surrounding the subsea transformer enclosure. A bushing chamber is further mounted to the transformer chamber, and a liquid tight seal is provided between the interior of the bushing chamber and the interior of the transformer chamber. The pressure compensation device includes first and second pressure compensators.

Abstract: A subsea transformer that includes a transformer and a transformer tank adapted to accommodate the transformer is provided. The transformer tank has an opening that is sized so as to enable insertion of the transformer into the transformer tank through the opening. A closing plate is adapted to close the opening of the transformer tank. At least one component having a double barrier against ingress of an ambient medium surrounding the subsea transformer when installed subsea is mounted to the closing plate.

Abstract: A subsea container electrical through connector for providing an electrical connection from an interior of a subsea container to an exterior of the subsea container is disclosed, wherein the connector extends partially into or fully through a hole in a subsea container. The connector comprises a conductive bolt having a conical bolt portion with an outer diameter increasing in a longitudinal direction. Further, the connector comprises an electrical insulator having a conical insulator portion with an inner surface, facing the conical bolt portion of the bolt, and an outer surface having an outer diameter which increases in the longitudinal direction.

Abstract: A subsea container electrical through connector for providing an electrical connection from an interior of a subsea container to an exterior of the subsea container is disclosed, wherein the connector extends partially into or fully through a hole in a subsea container. The connector comprises a conductive bolt having a conical bolt portion with an outer diameter increasing in a longitudinal direction. Further, the connector comprises an electrical insulator having a conical insulator portion with an inner surface, facing the conical bolt portion of the bolt, and an outer surface having an outer diameter which increases in the longitudinal direction.