Analysis of Overvoltage Faults in Offshore Wind Power Transmission Lines

Currently, Voltage Source Converter based High Voltage Direct Current (VSC-HVDC) transmission is widely employed in numerous domestic and international offshore wind farms. This approach offers several advantages including superior waveform quality, minimal transmission losses, support for large-scale wind farm construction, compatibility with weak power grids, environmental friendliness, and evident cost-effectiveness over long distances. However, the existing standards and specifications for VSC-HVDC systems in offshore wind farms are not yet comprehensive enough. Furthermore, research on fault types and system protection pertaining to this transmission mode remains insufficiently explored. In this study, a model of a VSC-HVDC transmission system specifically designed for offshore wind farms is established using PSCAD/EMTDC software. The impact of different fault types, fault timescales, and fault locations on the performance of the VSC-HVDC transmission system is investigated from both the DC side and AC side.