Overvoltage and Insulation Coordination of $\pm 500\text{kV}$ Offshore Wind Power Flexible DC Transmission System

With the fast development of offshore wind power technology, for the sake of increasing the security and dependability of wind farm operation, this paper mainly investigates the overvoltage and insulation coordination of offshore wind power grid-connected flexible direct transmission system. Firstly, the structure of offshore wind power network system is introduced. Then, employing the simulation platform PSCAD/EMTDC, based on a domestic engineering parameter, a simulation model of
$\pm \mathbf{500}\mathbf{kV}/\mathbf{2000}\mathbf{MW}$
flexible DC transmission system is established. According to the actual engineering situation, the typical fault condition setting, the voltage observation points setting and the arrester configuration scheme are expounded. Finally, the insulation level of the key equipment in the flexible DC converter station is obtained by simulating the key fault conditions and calculating the overvoltage level of each observation point and selecting the appropriate arrester parameters. The research results provide basic technical support for engineering implementation, and also provide reference for solving practical engineering problems.