Research On The Compound Failure Of The Chain And Thruster For A Mooring Assisted Dynamic Positioning System

With the human’s exploitation of ocean resources gradually moved to the deep sea,the requirements of floating structure’s positioning technology has become much higher.The traditional positioning methods of floating structures include mooring system and dynamic positioning system(DP system).Mooring system has a simple structure and high economy.The use of DP system is not subject to the water depth.Mooring assisted dynamic positioning system(PM system)is a new positioning method combining of DP system and mooring system and it has the advantages of high positioning accuracy,lower power consumption and high security.With the application of PM system becoming more and more widely,the research of PM system also become more deeply.Based on this background,this paper adapts the time domain simulation method to carry out some related research of PM system: 1)Based on the mathematical model of PM system,established the time domain simulation program of PM system in Matlab/Simulink.Then,a semi-submersible platform was been used as an example to perform the time domain simulation program of the DP system and PM system.2)Used the time domain simulation program to carry out some research on the compound failure of the chain and thruster for PM system.Through the time domain simulation,we can collect the positioning accuracy and power consumption.According to this results,we can evaluate the positioning security of the semi-submersible platform.Some of the conclusion will be helpful to the further engineering applications.3)In order to reduce the power consumption,proposed a new control method and applied it in the time domain simulation.According to the results of time domain simulation,this new control method can reduce power consumption effectively.In summary,based on the mathematical model,this paper established a time domain simulation program for the PM system.And then,carried some related research on the compound failure of the chain and thruster and the power consumption optimization.The conclusion of this paper will be helpful to the further engineering applications.