| Under the new world economic situation, to enhance the intensity of exploration andexploitation and to expand production of offshore oil and gas, is an important strategic movefor China’s energy development, which is an important way to improve the international voice,but also a political mission proposed by the nation. The reliability, accuracy, security, andeconomy of the positioning for the semi-submersible platform, which is one of the majorequipment types of deep-sea oil and gas exploration, is of profound significance in terms ofoil and gas production activities. However, the Position Mooring System along with itsrespective advantages over the Mooring System and Dynamic Positioning System, can assistthe semi-submersible platform to calmly deal with the harsh marine environment. Therefore,the research on the Position Mooring System is of great value.A positioning capability research for a semi-submersible platform equipped with PositionMooring System was present in this paper. Firstly, the environmental loads was calculated andanalyzed by theory and experimental study. Secondly, associating the environmental loads tothe platform dynamic response analysis, the mooring system and dynamic positioning systemdesign and verification were completed respectively. And then the both systems were coupledreasonablely based on the design of the control algorithm to form a Position Mooring System.Finally, according to the Position Mooring System working principle and motion model of theplatform, a platform motion simulation program under the control of the Position MooringSystem was developed to achieve a positioning capability study of Position Mooring system.During the design of the mooring system, the platform horizontal motion simulation programwas worked out by employing the catenary theory and quasi-static approach. And in thedesign of the dynamic positioning system, considering the mechanical characteristics, thethruster selection and arrangement was accomplished, followed by the semi-submersibleplatform static positioning capability evaluated. And then, by introducing the PID controltheory, Kalman filtering techniques and the thruster forces allocation model, the positioningcapability dynamic analysis program was built, and by utilization of which the positioning ofthe semi-submersible platform was investigated in time domain. |
