Jack-up platform
A jack-up platform ( 1 ) has a hull ( 2 ) and at least three longitudinally movable support legs ( 3 ) for the hull ( 1 ), at least one of the support legs ( 3 ) has at least one variable speed drive ( 8, 8 A1 to 8 F2 ) as a part of a leg driving mechanism, wherein the platform ( 1 ) has a closed-loop control unit ( 7 ) for the driving mechanism, the closed-loop control unit ( 7 ) being connected with the variable speed drive ( 8, 8 A1 to 8 F2 ) via a bi-directional electronic bus ( 16 ) for transmitting control parameters (M*,M,N,R).
1. A jack-up platform comprising a hull and at least three longitudinally movable support legs for said hull, at least one of said support legs comprising at least one variable speed drive as a part of a leg driving mechanism, wherein the platform comprises a closed-loop control unit for said driving mechanism, the closed-loop control unit being connected with said variable speed drive via a bi-directional electronic bus for transmitting control parameters, wherein said control unit comprises a speed controller which hands over a torque set-point to a torque controller of said variable speed drive via said bus connection.
2. The jack-up platform according to claim 1 , wherein the variable speed drive connects to a permanently excited motor.
3. The jack-up platform according to claim 1 , wherein the variable speed drive connects to an induction motor.
4. The jack-up platform according to claim 1 , wherein said torque controller is integrated into said variable speed drive.
5. The jack-up platform according to claim 1 , wherein said speed controller can receive an actual speed value of said variable speed drive via said bus connection.
6. The jack-up platform according to claim 5 , wherein a speed sensor validation module is disposed upstream of said speed controller.
7. The jack-up platform according to claim 6 , wherein said speed sensor validation module selects a most probable correct speed value and/or a speed value of a highest-bandwidth sensor.
8. The jack-up platform according to claim 1 , wherein the closed-loop control unit comprises a torque restriction module acting on said torque set-point output by said speed controller to said variable speed drive.
9. The jack-up platform according to claim 8 , wherein said torque restriction module can perform a combined torque/power limitation.
10. The jack-up platform according to claim 8 , wherein said torque restriction module can receive actual speed and actual torque values of said variable speed drive via said bus connection.
11. The jack-up platform according to claim 1 , wherein said closed-loop control unit comprises one respective speed controller for each support leg.
12. The jack-up platform according to claim 11 , wherein at least one support leg driving mechanism comprises more than one variable speed drive.
13. The jack-up platform according to claim 12 , wherein each variable speed drive of said multi-drive support leg comprises one respective torque controller connected with the respective speed controller via said bus connection.
14. The jack-up platform according to claim 1 , wherein said bi-directional electronic bus is a high-speed field bus or an Ethernet.
15. A method of operating a jack-up platform comprising a hull and at least three longitudinally movable support legs for said hull, the method comprising the steps of:
providing at least one of said support legs with at least one variable speed drive as a part of a leg driving mechanism,
operating said driving mechanism with a closed-loop control unit,
transmitting control parameter by the closed-loop control unit via a bi-directional electronic bus, and
handing over a torque set-point to a torque controller of said variable speed drive via said bus connection.
16. The method according to claim 15 , further comprising the step of receiving an actual speed value of said variable speed drive at said speed controller via said bus connection.
17. The method according to claim 16 , wherein a speed sensor validation module is disposed upstream of said speed controller, and the method further comprises the step of selecting by said speed sensor validation module at least one of a most probable correct speed value and a speed value of a highest-bandwidth sensor.
18. The method according to claim 15 , wherein the closed-loop control unit comprises a torque restriction module acting on said torque set-point output by said speed controller to said variable speed drive, and the method further comprising the step of performing by said torque restriction module a combined torque/power limitation.
19. A jack-up platform comprising a hull and at least three longitudinally movable support legs for said hull, at least one of said support legs comprising at least one variable speed driving mechanism controlled by a closed-loop control unit connected with said variable speed drive via a bi-directional bus for transmitting control parameters, wherein said closed-loop control unit comprises a speed controller operable to transmit a torque set-point to a torque controller of said variable speed drive via said bi-directional bus.
20. The jack-up platform according to claim 19 , wherein the variable speed drive connects to a permanently excited motor or to an induction motor.