Research On Assessment And Optimization Of Dynamic Positioning System Of Semi-submersible Platform

Because of the increasing demand of deep-water exploration of marine resources, the traditional multi-point mooring location can no longer meet the operational requirements of the positioning of deep-sea waters. The dynamic positioning system used in marine equipment is well adapted to the requirements of deep-sea operation targeting. It solves the problems of traditional anchor position about the economic cost, technology of installation, Operating water depth, etc, and it also has high positioning accuracy and fast response, structural safety, strong mobility and so on.Dynamic positioning system, through the current ship position measuring system detects the phase deviation for the reference point, collecting environmental parameters to calculate the ship back to the reference position required for thrust. To allot the thrust of the thruster system, and to determine the direction of the propulsion thrusters, pitch and speed, so that the ship or platform can keep the bow in setting the direction and position. The thrust output of the thrust system and distribution of power, the total energy consumption, the choice of the number of thrusters and the position of the layout is an optimized calculation process.In this article, we summarized the research and development status of the dynamic positioning system and the optimization algorithmthe method of the thrust allocation at home and abroad .Discussed the form of thrusters of the dynamic positioning system and some basic performance parameters, as well as the hydrodynamic interference of the thrusters and hull, thrusters and thrusters and also the calculation methods of the thrust attenuation coefficient.According to the estimated results of the environmental loads of the semi-submersible platform in the sea under certain wind, wave and tidal current, we use non-linear programming method with the optimization toolbox of MATLAB to optimize the thrust of the thruster allocation calculations and calculated the dynamic positioning capability curve with examples.Taking into account the failure modes and dynamic positioning system control, security, economy, and the response time and other factors, we take an analysis of the design and determined the best optimization of the program.