| 摘要 |
A hydrocarbon production system comprises a topside installation connected to a underwater distribution unit 4 by an umbilical 3. The unit 4 is connected to Christmas Trees 8, 9 and 10 by respective ones of jumper interconnects 11, 12 and 13. Each Christmas Tree may comprise one or more of an electrical actuator 14, flow rate control choke 16, pressure and/or temperature transducers 18, down hole measurement transducers 18a and/or a down hole safety valve 21. Electrical power is transmitted to the unit 4 by a high voltage transmission cable forming part of the umbilical 3. A transformer forming part of the unit 4 steps down the voltage transmitted over the umbilical 3 to a level suitable for use by the electrical devices 14, 16 and 21. Power and control of the devices 14, 16, 18, 18a, 21 is effected by an underwater controller 5, 6, 7 associated with its respective Christmas Tree 8, 9, 10. Control and measurement data may be effected between the topside station 2 and the Christmas Trees 8, 9, 10 by communication signals modulated onto the high voltage transmission cable, a low voltage transmission line or a dedicated communications line forming part of the umbilical 3. In other embodiments (FIG. 3, FIG. 4, not shown) one or more field buses are used to communicate data and power to the devices 14, 16, 18, 18a and 21 and an underwater controller 5, and/or between the unit 4 and a plurality of underwater controllers. |
