Design And Research Of The All-electric Subsea Control System

As the indispensable part of marine oil and gas development,subsea production control system has gone through the development process of the full hydraulic control system and electrohydraulic control system and all-electric control system.Electrohydraulic control system is currently the most mature technology.With the increase of depth development,valve opening time becomes slow due to the serious loss of the hydraulic energy.Electrohydraulic control system is difficult to meet the requirements of subsea production.However,all-electric control system has the advantages of fast response,high control precision,long transmission distance and so on,which will be of great significance to China's offshore oil exploitation.This paper carried out research and development on the control module in the all-electric control system.The work done in this paper is as follows.In this thesis,subsea production systems are analyzed,and the information of main functions of all-electric subsea control module,all-electric valve actuator and electrical connector is collated.On this basis,the research and design of all-electric subsea control module and electrical connector are completed.The design requirements and performance index of the all-electric subsea control module are proposed,and the overall mechanical scheme of the control module is designed.Two kinds of electrical control schemes are compared and analyzed,and the optimal control scheme is determined as integrated control.The key components of the control module are analyzed in detail.The thermal balance structure of 500 m undersea electronic module is designed,and the strength analysis and stability check of the shell are carried out.A set of ROV operating locking mechanism is designed.The contact angle of the locking block is determined,and the strength of the lead screw and the locking block are checked.The mechanical alignment accuracy of the docking plate is designed,and the strain and strength of the docking plate with the limiting pin are analyzed.The design of the PC104 hardware system based on Vx Works embedded system is completed.The main program and data acquisition,switch quantity control and communication program subroutine design of the module are completed.The test environment of the master station is established to verify the function of the control module.According to the requirements of the control module,the function and performance index of subsea wet-mate electrical connector are proposed.The whole structure is designed and the key technic of subsea wet-mate electrical connector including dynamic seal structure,insertion sequence structure and pressure-balancing structure is determined in detail.The mathematical model is established between the stress and contact spring structure parameters and the strength of contact spring is checked.The effect of different structure parameters on the stress is studied from the numerical simulation of insertion process of contact spring by using ANSYS Workbench analysis.The influence of the sealing gap and the friction coefficient of the contact seal on the sealing structure is analyzed,and the optimal value of the sealing parameters is determined.