Analysis of the Jeju Island Power System with an Offshore Wind Farm Applied to a Diode Rectifier HVDC

The Jeju Island power system consists of two-unidirectional high voltage direct current transmission systems (HVDC), thermal power plants, and renewable energy sources. The local government’s policy states that a 100 MW offshore wind farm should be constructed in the future. Due to the small size and sensitivity of the Jeju Island power system, power system analysis must be carried out before the installation of the new facility. Therefore, the objective of this study was to analyze the Jeju Island power system with a new wind farm applied to uncontrolled diode rectifier HVDC. Although there are many studies about the grid connection method of offshore wind farms, its small grid connection analysis has been rarely investigated, especially in the diode rectifier HVDC method. Diode rectifier HVDC is a new grid connection method for offshore wind farms, which reduces the costs and increases the reliability of the offshore platform. To verify the accuracy and effectiveness of simulation models, steady and transient state scenarios were conducted using the PSCAD/EMTDC program. First, the model of the Jeju Island power system without a new wind farm was compared with measured power system data. Second, its power system connected with a diode rectifier HVDC was simulated in a steady state. Finally, disconnection and single line ground fault occurred at the offshore wind farm, respectively. From the simulation results, the grid stability of the Jeju Island power system was confirmed considering a new facility.