Simulation Analysis And Experimental Research On The Principle Prototype Of Riser Flexible Hang-off

The riser is the key equipment for the operation of the offshore drilling platform.When the typhoon comes,the drilling platform needs to stop the operation to avoid the platform and evacuate.Considering the time cost and economic cost,the riser is suspended on the platform and then evacuated together.Affected by wave fluctuations,the riser is prone to failure during evacuation,and may cause damage to the platform in severe cases.For this reason,higher requirements are put forward for the riser suspension system.The flexible hang-off device reduces the acceleration of the riser by controlling the movement of the hydraulic cylinder to improve the dynamic load of the riser.In order to verify the compensation performance of the flexible hang-off device,a prototype of the flexible suspension principle was designed according to similar principles.This paper takes the flexible hang-off principle prototype as the research object,and the principle verification of the compensation effect of the principle prototype is carried out.Use ADAMS to build the mechanical system of the principle prototype,including the heave simulation system,dynamic load compensation system and load system.The mechanical system was verified to ensure the realization of the expected motion;according to the control requirements of the system,The hydraulic control system of basic differential equations is established by using Simulink.Using the state variables such that between ADAMS and Simulink exchange data,to achieve co-simulation.Based on ADAMS/SIMULINK co-simulation,build different controller models for comparative analysis,including PID control,fuzzy control and fuzzy PID control.The influence of proportional,integral,and differential coefficients on the control is compared and analyzed for PID control.For fuzzy control,the influence of membership function shape,fuzzy subset distribution and number of subsets are analyzed.Use fuzzy inference to adjust PID parameters online.The simulation results show that fuzzy PID is superior to the other two methods in terms of control accuracy and control stability.The test system of the principle prototype is designed,including hydraulic system and electronic control system.The key parameters of hydraulic components are established through co-simulation analysis,including the initial volume of the accumulator,the pre-charge pressure of the accumulator and the time constant of the throttle valve,and select hydraulic components.The control system adopts the DCS system,the industrial computer and the acquisition card use the PCI communication method to realize data acquisition and motion control,and the control hardware is selected.Developed the principle prototype control program,and realized the interaction of the man-machine interface using VB and Access.The program can realize functions such as motion control,information monitoring,curve display and data storage.Based on the test system,carry out the experimental research of the principle prototype,including system debugging,heave simulation and dynamic load compensation.Through carrying out unilateral compensation and bilateral compensation experiments,the results show that the principle prototype has a certain compensation effect.