North Sea Submersible Drilling Platform Dynamic Positioning System Design

In the vast North Sea,eight kilometers below the sea floor,there are abundant oil and natural gas resources.It has the world's third largest undersea oil reserves.It likes a natural energy store.Norway is one of the countries around the "natural energy store",whose economies have sprung up because of this vast natural treasure trove.However,the sea conditions in the North Sea are bad,and most of the year is cloudy and rainy,with high winds and waves.This puts higher requirements on the performance of platforms operating in the Norwegian North Sea:suitable for deep water operations;accurate positioning and stable and reliable performance.The development of dynamic positioning systems for oil drilling units has brought hope to oil companies.Dynamic positioning(DP)system is classified as three grades,DP grade 1(DP1),DP grade 2(DP2),DP grade 3(DP3),DP3 is the most safe and reliable.For many years,DP3 systems of domestic offshore drilling units had been purchased from abroad,especially the projects in the operation area in the North Sea.The reasons are not only the DP3 system highly complex,but also the complex environment in the North Sea with many factors affecting the system.The codes and regulations for the projects in this area are stricter than other sea area.In order to realize indoor design and indoor purchasing to reduce the cost,a detail explanation of DP system design for North Sea area operating submersible platform will be given in this paper based on a real project.The works are including:1.DP capability analysis based on the North Sea environment and DNV rules requirement.Confirm the capacity of thrusters.2.To confirm the capacity of main engine through load balance analysis.3.Design of thruster control system,including thruster status monitoring and feedback,thruster control(local and remote)and thruster auxiliary equipment monitoring and control.4.DP control system design,this part includes DP3 power positioning system control part specification analysis,system construction,equipment selection and interface definition.5.DP3 system FMEA analysis,which is the theoretical verification of the designed DP3 system,using the "FAT " method to analyze layer by layer and eliminate risks.Finally,The design can be verified that it meets the requirements of ERN(99,99,99,99),and its redundancy meets the requirements of DP3 through software simulation.