Design And Simulation Research On Fuzzy Auto-tunning Weather Optimal Positioning Controller

Dynamic Positioning system is closed-loop control system that consistently measures the difference between actual position and desire position, then calculates and sends signals to the thruster to get the control force/torque needed to counterpart the environment disturbance, so that the ship or platform can be positioned at the desired position or track the pre-determined ship courses.Weather Optimal Positioning Control refers to the control strategy that using the thrusters to adjust the ship heading to the mean environment disturbances (wind, waves, currents) as well as keep the ship at its desired position. Relative researches show WOPC controller reduced the usage of lateral thrust force when the ship holds the weather optimal heading. Hence much smaller amount of energy is needed, NOx-SOx emission and mechanical wear of thrusters are also reduced.At the beginning, this paper introduces relative research works both domestic and aboard as well as the ship mathematic model for simulation experiment. Then ship WOPC design and simulation based on Matlab is carried out. Analysis show that the designed WOPC is successful and have the advantages mentioned above. Next, this thesis put forward Fuzzy Auto-tuning methodology for WOPC controller parameters, to improve the controller’s dynamic and static control results.Simulation results show that by adding parameter Fuzzy Auto-tuning methodology to WOPC, the control results not only maintained the original advantages over traditional DP controllers such as energy-saving and emission-reduction, but also has better dynamic and static performance with improved economic and safety characteristic than WOPC controllers.