Faults mitigation control design for grid integration of offshore wind farms and oil & gas installations using VSC HVDC

This paper presents an analysis and new fault mitigation methods of grid integration of offshore wind farms and oil & gas installations using Voltage Source Converter (VSC) HVDC transmission system. On the fault occurrence in the onshore AC grid, the proposed DC link voltage controller initiates fast output power drop of the wind farm, in order to avoid the overvoltage in the DC transmission link. On the faults occurrence in the oil & gas installation, the proposed control employs a voltage-dependent limiter, to limit the maximum amount of active power from the offshore VSC. Simulation results in PSCAD / EMTDC show the satisfied performance of the proposed control strategy for the case of one 300 MW VSC transmission system connecting an offshore wind farm and oil & gas installations to the grid.