LCC DC Grids and LCC/VSC Hybrid DC Grids: Feasibility and Reliability Analysis
Hybrid HVDC schemes for future Global Grid Interconnection
High-voltage direct-current (HVDC) technology which has been used for more than 70 years is suited to transport large amounts of power over long distances with minimum losses. Thyristor-based line commutated converter (LCC) HVDC is used for transferring bulk power (over several GW) over long distances due to its mature technology that is efficient, reliable and cost-effective. However, LCC-HVDC brings some inherent problems, such as commutation failure, difficulty in connecting weak AC systems, and the need for DC voltage polarity reversal during power flow reversal. These obstacles make this technology difficult when considering large-scale DC grids.