Research On The Corrosion Influence Of Offshore Facilities Caused By HVDC-flexible

HVDC-flexible is used in the power supply of offshore platform increasingly because of its own merits, but the attendant potential grounding current is likely to lead offshore facilities to suffer from stray current corrosion, which can shorten the life of offshore facilities, and even destroy the structure of the offshore facilities and cause serious accidents, Therefore, it is necessary to study the adverse influence which the grounding current of HVDC-flexible may cause on offshore facilities. This paper uses the numerical simulation software based on the boundary element method to research on the influence of grounding current on offshore facilities, and verify the result of numerical simulation by carrying out real experiments, as well, this papers presents a method to suppress the influence of grounding current and carry out real sea experiments to verify the feasibility of the method.Firstly, this paper describes the numerical simulationg technology based on the boundary element, and analyzes the reasons for corrosion risk of offshore facilities caused by HVDC-flexible when it is used to suppy power to platform, and determine the simulation conditions based on the reasons, and establish the scale models according to the actual offshore facilities which are protected by impressed current cathodic protection or sacrificial anode cathodic protection for numerical simulation calculation. On this basis, respectively, for the protection of the sacrificial anode and impressed current protection scale model, through the analysis of numerical simulation results give significant influence law of the three factors, the groud current magnitude and direction, the groud electrode distance and the groud electrode relative position that affect the corrosion of offshore facilities that influence by ground current. Finally, built the real sea experimental jacket model corresponding to the numerical simulation, and carry out the real sea experiments, and compare the experimental results with the simulaional results of jacket model which are protected by impressed current or sacrificial anode respectively to verify the accuracy of numerical simulation tesults. This indicate that the boundary element cathodic protection numerical simulation software used in this paper can accurately predict the influence of grounding current on the corrosion of offshore facilities, and it can be a powerful tool for study on the influence of grounding current on the corrision of offshore platform,. What's more, this paper propose and verify a method to suppress the influence of grounding current on offshore platform by carrying out real sea experiment on jacket platform which is protected by impressed current cathodic protection. This can provide technical support for the safe operation of offshore facilities which use HVDC-flexible for power supply.