Research On DP-3 System For Deepwater Drilling Ship

Dynamic positioning system is that vessel could maintain position and keep heading without by mooring, which calculate thrust force and allocate them into each thruster to withstand external loads on the platform due to wind, current, wave comparing actual postion with required postion. In the deep water area, dynamic positioning system has been widely applied in vessel and offshore industry.Regarded as top level in dynamic positioning system, DP-3 notation require vessel could still keep station within a specified operating under speificed environmental condition under any single fault, including complete loss of a compartment due to fire or flood. Therefore the redundancy should be considered by failure mode effect analysis to entire system. This article is based on the sixth-generation 3000 m drilling ship to study dynamic positioning system.According to actual project, explain the configuration with electrical power system, thruster system and DP control system in deepwater drilling ship. Introduce the power system composition and thruster system. Finaly illumate DP control and mearsure system.After the system configuration comfirmed, take a research into dynamic postion capability analysis. The environment loads such as wind, current, wave force are analyzed using external data. Then explain relevant thruster data including type, location, forbidden zones, etc. When the forementioned data including vessel main dimensions, environment condition, thruster parameter input into DPCAP software, the DP capability plot under design condition will be obtained in intact mode and all kinds of failure mode to verify the security and reliability of DP system.The Failure Mode and Effect Analysis(FMEA) method is generally a tool for qualitative analysis of risk through identification of failure modes and corresponding effects to personal, equipment, environment and operation in power, thruster, DP control section. After identify failure mode for each system and go through identified critical failure mode, make a record of each critical failure mode effect in addition to DP capability plot to prove that DP system could work well and has a good security performance.