With the increasing of the scale of offshore wind turbines and investment and the gradual decline of construction costs

offshore wind power resources are becoming increasingly scarce. Large scale and long distance offshore wind power transmission project based on voltage source converter based high voltage direct current (VSC-HVDC) technology have been widely deployed. In offshore wind power VSC-HVDC transmission project

the DC voltage level is an important technical parameter to reflect the transmission capacity. Based on the limitation requirements of steady state and the transient ampacity of IGBT devices as well as DC marine cables

a method for determining DC voltage level of offshore wind power VSC-HVDC transmission project is proposed. On this basis

taking a 900 MW offshore wind power VSC-HVDC transmission project for example

the process of determining DC voltage level of the engineering case is given. The proposed method is conducive to reducing construction costs

which is of great significance to promote the large scale intensive development of offshore wind power and the development of gridintegration technologies.