Electric control and supply system

• US 8,212,410 B2
• Filed: 09/25/2009
• Issued: 07/03/2012
• Est. Priority Date: 11/12/2002
• Status: Active Grant

• Current Assignee: Onesubsea IP UK Limited (Schlumberger NV)
• Original Assignee: Cameron International Corporation (Schlumberger NV)
• Inventors: Biester, Klaus, Kunow, Peter, Lenz, Norbert
• Primary Examiner(s): KAPLAN, HAL IRA
• Application Number:
  US12/567,105
• Publication Number:
  US 20100019930A1
• Time in Patent Office: 1,012 Days
• Field of Search: 307/82
• US Class Current: 307/82
• CPC Class Codes: E21B 33/0355 Control systems, e.g. hydraulic, pneumatic, electric, acoustic, for submerged well heads
• CPC Class Codes: F16K 31/041 for rotating valves F16K31/055 takes precedence
• CPC Class Codes: F16K 31/046 with electric means, e.g. electric switches, to control the motor or to control a clutch between the valve and the motor F16K31/041 takes precedence
• CPC Class Codes: F16K 31/047 characterised by mechanical means between the motor and the valve, e.g. lost motion means reducing backlash, clutches, brakes or return means F16K31/043 takes precedence
• CPC Class Codes: F16K 37/0083 by measuring valve parameters
• CPC Class Codes: H02J 1/06 Two-wire systems
• CPC Class Codes: H02J 13/00009 using pulsed signals
• CPC Class Codes: H02J 13/00017 using optical fiber
• CPC Class Codes: H02J 3/36 Arrangements for transfer of electric power between ac networks via a high-tension dc link
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/0074 Plural converter units whose inputs are connected in series
• CPC Class Codes: H02M 1/0077 Plural converter units whose outputs are connected in series
• CPC Class Codes: H02M 7/04 by static converters
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: H02P 5/68 controlling two or more dc dynamo-electric motors H02P5/46, H02P5/60 take precedence
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y02E 60/60 Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
• CPC Class Codes: Y04S 40/121 using the power network as support for the transmission
• CPC Class Codes: Y04S 40/124 using wired telecommunication networks or data transmission busses

Abstract

In at least some embodiments, an electrically controlled subsea production system includes a subsea electrical distributor that receives a high direct current (DC) voltage. The electrical distributor converts the high DC voltage to a lower DC voltage. The electrically controlled subsea production system also includes a plurality of subsea trees coupled to the subsea electrical distributor, wherein valves of the subsea trees selectively operate based on the lower DC voltage.

Claims

1. An electrically controlled subsea production system, comprising:

a subsea electrical distributor configured to receive a high direct current (DC) voltage, wherein the electrical distributor is configured to convert the high DC voltage to a lower DC voltage; and

a plurality of subsea trees coupled to the subsea electrical distributor, wherein each of a plurality of motor-operated valves for each subsea tree is configured to selectively actuate using the lower DC voltage;

wherein the subsea electrical distributor is configured to separate communications from the high DC voltage before the high DC voltage is converted to the lower DC voltage; and

wherein the subsea electrical distributor is configured to forward said communications to said subsea trees with the lower DC voltage.

2. The electrically controlled subsea production system of claim 1 wherein the lower DC voltage is at least 5 times less than the high DC voltage.

3. The electrically controlled subsea production system of claim 1 wherein the lower DC voltage is at least 10 times less than the high DC voltage.

4. The electrically controlled subsea production system of claim 1 wherein the subsea electrical distributor comprises a plurality of DC/DC converters that operate together to convert the high DC voltage to the lower DC voltage.

5. The electrically controlled subsea production system of claim 1 wherein each subsea tree has an electrical control pod mounted thereto and wherein each electrical control pod is configured to selectively receive the lower DC voltage and communications.

6. The electrically controlled subsea production system of claim 5 wherein each subsea tree comprises a plurality of electrically actuated valves and wherein each electrical control pod comprises an electronic module that is configured to selectively control actuation of said plurality of electrically actuated valves based on control signals separated from the high DC voltage.

7. The electrically controlled subsea production system of claim 6 wherein real time diagnostics and position measurement is provided for each of said plurality of electrically actuated valves.

8. A method for an electrically controlled subsea production system, comprising:

receiving a high direct current (DC) voltage at a subsea location;

separating communications from the high DC voltage;

converting the high DC voltage to a lower DC voltage at the subsea location;

distributing the lower DC voltage to a plurality of subsea trees;

forwarding the communications to the subsea trees with the lower DC voltage; and

selectively actuating each of a plurality of motor-controlled valves of each subsea tree using the lower DC voltage.

9. The method of claim 8 wherein converting the high DC voltage to a lower DC voltage comprises converting the high DC lower to a DC voltage that is at least 5 times less than the high DC voltage.

10. The method of claim 8 wherein converting the high DC voltage to a lower DC voltage comprises converting the high DC lower to a DC voltage that is at least 10 times less than the high DC voltage.

11. The method of claim 8 wherein converting the high DC voltage to a lower DC voltage comprises operating a plurality of DC/DC converters together to convert the high DC voltage to the lower DC voltage.

12. The method of claim 8 further comprising selectively controlling actuation of a plurality of electrically actuated valves for each subsea tree based on control signals that have been separated from the high DC voltage.

13. The method of claim 12 further comprising providing real time diagnostics and position measurement for each of said plurality of electrically actuated valves.

14. A method for an electrically controlled subsea production system, comprising:

receiving a high direct current (DC) voltage;

converting the high DC voltage to a lower DC voltage;

distributing the lower DC voltage to a plurality of subsea trees;

selectively operating valves of each subsea tree based on the lower DC voltage; and

separating communications from the high DC voltage before converting the high DC voltage to the lower DC voltage and adding the communications to the lower DC voltage for selective distribution to said subsea trees.

15. A subsea wellhead assembly, comprising:

a subsea electrical distributor configured to receive a high direct current (DC) voltage, wherein the electrical distributor is configured to convert the high DC voltage to a lower DC voltage; and

a plurality of subsea trees coupled to the subsea electrical distributor, wherein valves of the subsea trees are configured to selectively actuate using the lower DC voltage,

wherein the subsea electrical distributor comprises a plurality of redundant DC/DC converters that are configured to operate together to convert the high DC voltage to the lower DC voltage;

wherein the lower DC voltage is at most 300 Volts and the high DC voltage is at least 3000 Volts;

wherein the subsea electrical distributor is configured to separate communications from the high DC voltage before the high DC voltage is converted to the lower DC voltage; and

wherein said subsea electrical distributor is configured to forward said communications to said subsea trees with the lower DC voltage.

16. The subsea wellhead assembly of claim 15 wherein each subsea tree has an electrical control pod mounted thereto and a plurality of electrically actuated valves, wherein each electrical control pod is configured to selectively receive the lower DC voltage and communications from the subsea electrical distributor and wherein the electrical control pod is configured to selectively control actuation of said plurality of electrically actuated valves based on control signals separated from the high DC voltage.