A distribution system includes: at least one Power Management System (PMS) that controls electrical power transmitted by the distribution system; and a first power station located at an onshore platform including an onshore terminal that distributes electric power to the first power station and to at least one onshore load, a plurality of onshore reactors that monitor inbound reactive power received from the onshore terminal or that monitor outbound reactive power sent to a remote location, and an onshore synchronous motor that operates on the inbound reactive power received from the onshore terminal.

The invention provides a subsea pressure boosting system feasible for operation at subsea step out lengths above 40 km and by control merely from a dry topside or onshore location. The system is distinctive in that it comprises: at least one subsea power step out cable, arranged from a near end at a dry location onshore or topsides to one or more subsea loads such as subsea pumps or subsea compressors at a far end, at the near end at least one source for electric power is connected and the cable is dimensioned for operation at a frequency different from the operation frequency of the connected subsea loads in order to handle the Ferranti effect and electric losses, and at least one passive electric frequency transformer, operatively connected between the subsea step out cable far end and the subsea loads, said transformer is located in a pressure vessel and transforms the operation frequency of the subsea step out cable to a frequency feasible for operation of the connected loads.

A method for transferring electrical power in the sea includes generating AC power, guiding, at least partially underwater, the AC power through a cable from a first end of the cable to a second end of the cable, and changing a frequency of the AC power guided through the cable based on a value of power consumption of a load connected to the second end of the cable.

A method for transferring electrical power in the sea includes generating AC power, guiding, at least partially underwater, the AC power through a cable from a first end of the cable to a second end of the cable, and changing a frequency of the AC power guided through the cable based on a value of power consumption of a load connected to the second end of the cable.

A method for detecting high-frequency traveling waves in an electrical system by use of current sensors, the method including arranging association of at least one current detection sensor with at least one conductor in the electrical system, where the at least one conductor is associated with at least one parasitic capacitance; receiving at least one measurement from the at least one current detection sensor, where the at least one measurement is based on flow of stray current through the at least one parasitic capacitance; and detecting, based on the at least one measurement, a traveling wave that corresponds to the stray current, where the flow of the stray current through the at least one parasitic capacitance is based on propagation of the traveling wave through the at least one conductor. Disclosed is also an arrangement for detecting high-frequency traveling waves in an electrical system.