Transmitting electrical power and communication signals

Abstract

The invention relates to transmitting electrical power and communication signals. A system for transmitting electrical power and communication signals, comprises a transmission line (3); a source (5) of electrical power for supplying electrical power to the transmission line; first communication means (10) for supplying communication signals to the transmission line; power extraction means (4, 6, 7) for extracting and using electrical power from the transmission line; second communication means (11) for receiving communication signals from the transmission line; and control means (8, 9) for controlling operation of the system in such a way that, in use of the system, the power source supplies electrical power to the transmission line for respective periods of time which are different from respective periods of time in which the first communication means supplies communication signals to the transmission line.

Description

technical field [0001] The present invention relates to the transmission of electrical power and communication signals. Background technique [0002] One of the implementation techniques used in offshore production control systems for hydrocarbon extraction wells to transmit control and instrumentation signals between surface equipment and subsea equipment installed on the seabed is the use of communication over power (COP), Wherein the communication signal is superimposed on the power signal and transmitted simultaneously with the power signal along the power transmission line in the umbilical cable. [0003] This approach is employed to reduce the number of wires required within the umbilical that provides the primary interface between above and below water equipment for both hydraulic and electrical power. Using a COP eliminates the need for separate power and communication lines within the umbilical, thereby reducing its overall cost. [0004] However, this technique d...

AI Technical Summary

Problems solved by technology

[0004] However, the technique does have some inherent disadvantages as follows

[0005] At the subsea equipment level, there is a need to separate and retrieve the communication signal from the power signal with large equipment such as communication blocking filters and duplexers, and this process can result in the generation of electrical noise and transients

These subsea components also consume electricity

[0006] The quality of the power generated above the water and transmitted through the umbilical cable can be poor and contain electrical noise and harmonics at typical 50 / 60Hz power frequencies and these can interfere with low power communication signals superimposed on the power signal

[0007] Sudden voltage transients, such as those caused by switching surges or sudden changes in electrical loads, can interfere with high-frequency communication signals

Images