A Study on Hybrid AC/DC Transmission System Planning for Improving the Hosting Capacity of Offshore Windfarms
Hyeon Woo, SeongJun Park, Sungyun Choi · The Transactions of The Korean Institute of Electrical Engineers · 2025
The global transition to renewable energy has accelerated the adoption of offshore wind power. To ensure the stable transmission of large-scale offshore wind energy, hybrid AC/DC transmission expansion planning is essential. This paper proposes a hybrid AC/DC transmission expansion strategy to enhance the hosting and transmission capacity of offshore wind farms. This methodology accounts for the characteristics of embedded HVDC systems and considers both AC and DC contingencies. For DC grids, an optimal operating range determination methodology for multi-terminal DC (MTDC) systems is proposed from an operational planning perspective to improve transient stability. For AC grids, a FACTS placement methodology is introduced from a facility planning perspective to enhance AC line flow limits, conducting FV analysis. The proposed hybrid AC/DC transmission expansion framework is validated on the Korean power system, demonstrating its effectiveness in enhancing grid stability and capacity.