Study On Thrust Allocation Strategy And Controller Parameters Optimization Of Dynamic Positioning System

Dynamic positioning system is playing an increasingly important role in the marine engineering field.Dynamic positioning system requires higher the performance and economics.In this paper,research on the optimization of thrust distribution system and controller parameters in dynamic positioning systems were conducted.Firstly,the related theories of dynamic positioning and time domain simulation mathematical model of dynamic positioning system were introduced.Based on this model,a time domain simulation program of dynamic positioning system was developed.A semisubmersible drilling platform was used as a research object,and the time domain simulation of the dynamic positioning system was carried out.A model test of thrust loss caused by hydrodynamic interference of the dynamic positioning system of the semi-submersible platform was carried out.BP neural network was used to fit the thrust loss function,and the thrust loss function was introduced to the mathematical model of thrust distribution.A simple and feasible method of thrust allocation considering thrust loss was proposed.This method can effectively avoid thrust loss and reduce power consumption on the premise of meeting thrust requirements.Based on the reinforcement learning theory,a parameter optimization strategy for the PID controller of a dynamic positioning system was proposed.The time domain simulation program was used to verify the results.The results show that this method can effectively adjust the parameters of the PID controller of the dynamic positioning system to meet the positioning requirements.In summary,research on the thrust allocation strategy and parameter optimization of the dynamic positioning system were conducted.The conclusions will provide some useful guidance to improve the performance of the dynamic positioning system.