Research on Seismic Analysis of Converter Valve of Offshore Flexible High Voltage Direct Current Considering the Effect of Initial Displacement

Abstract

Due to the acceleration of global energy transformation and the reduction of the cost of new energy, offshore wind power has been attached great importance by many countries. Therefore, offshore wind power transmission based on flexible HVDC transmission technology has become a hot issue in the development and research of offshore wind power. When the offshore platform is running for a long time, there may be extreme conditions of encountering earthquake. As the core component of flexible HVDC transmission, converter valve's structural safety research under earthquake is very necessary. Different from the onshore converter station and limited by the installation environment, the bottom support insulator of offshore converter valve tower may have initial displacement after being installed on the foundation plate of offshore platform. However, there is no literature on the effect of initial displacement on the dynamic characteristics and seismic performance of valve towers. In this paper, a practical engineering valve tower is taken as an example. Firstly, the influence of different initial displacements on the dynamic characteristics of valve tower is studied. Then, the dynamic analysis of valve tower under earthquake load is carried out by using time history integration algorithm. The influence of initial displacement on the structural safety of valve tower is studied by comparison method. The results of this paper can provide reference for similar projects.