Onesubsea IP UK Limited

Framo Engineering As

Aage Hadler-Jacobsen

Audun Magne Askeland

Jørgen Eide

Asbjoern Diesen

The present disclosure relates to system and method used to transmit power to a remote location. More specifically, the present disclosure relates to a system and method used to independently energize control and monitoring functions of a remote installation prior to and/or during energizing its main circuit.

Supply of auxiliary power to remote installations

Low frequency power is transmitted over long distances from a surface power supply to a subsea rotating machine, such as a pump or compressor. The low frequency power is used to rotate a motor at low speed. A liquid filled magnetic step-up gear module might be used to increase the low speed motor shaft to a higher speed output shaft that can be used to operate the rotating machine. The magnetic gear module can be configured as a fixed ratio, and the surface power supply can be configured to adjust the power frequency to change the speed of a single subsea rotating machine. In other embodiments, the magnetic gear module can provide a variable gear ratio. A fixed low frequency might be transmitted from the surface and multiple subsea loads can be operated from the same power source, each having their own variable magnetic gear module.

Long distance power transmission with magnetic gearing

According to some embodiments, two or more subsea motors are run simultaneously from a common topside frequency converter and a single set of three-phase cores within an umbilical cable. The subsea distribution system, which may include a subsea transformer distributes the power to the electrical motors. Current sensor and measuring electronics are used to measure current on one or more of the phases used to drive each motor. Measurement data is transmitted to the surface where an analysis system is used to detect possible load imbalance conditions between the motors.

Monitoring multiple subsea electric motors

A pressure-compensated fuse assembly may include a first chamber housing a first fluid and a plurality of solid particles. Additionally, the fuse assembly may include a second chamber housing a second fluid. Further, the fuse assembly may include a pressure compensator disposed between the first chamber and the second chamber. The pressure compensator may be configured to transfer pressure from the second fluid in the second chamber to the plurality of solid particles in the first chamber.

Pressure-compensated fuse assembly

A seawater-based high resistance grounding device for a subsea transformer includes an insulated pipe mounted to the outside of the transformer so as to be exposed to seawater. The insulated pipe has two or more cylindrical metallic electrodes electrically connected to ground and to the neutral node of the secondary transformer windings. The volume of seawater within the pipe and between the electrodes provides one or more high resistance ground paths for protection of the transformer.

Subsea transformer with seawater high resistance ground

A fluid pump system comprises an electrical drive unit and a rotary pump comprising a rotatable shaft and a drive element formed from a number of impellers attached to the shaft for causing flow within a process fluid. The electrical drive unit comprises an electrical stator and an electrical rotor attached to the shaft via a coupling, the electrical stator being disposed adjacent to the electrical rotor. The electrical stator is disposed within a first casing and the rotary pump and the electrical rotor are disposed within a second casing. The first casing contains a first fluid and the second casing contains a second fluid.

Growing community of inventors

Nesttun, Norway

Aage Hadler-Jacobsen