The combination of Doubly-Fed Induction Generators (DFIGs) with High Voltage Direct Current (HVDC) transmission systems holds immense promise for advancing wind energy conversion systems (WECS). This book provides a concise overview of the integration of DFIGs with HVDC in WECS. It discusses the operational principles and advantages of DFIGs, emphasizing their variable-speed operation and grid-friendly characteristics. Additionally, it highlights the capabilities of HVDC technology for efficient long-distance power transmission. The synergy between DFIGs and HVDC systems is explored, showcasing their role in enhancing grid integration, stability, and overall system performance. Control strategies for optimizing power generation and grid stability in DFIG-HVDC systems are also discussed. Finally, the paper addresses ongoing research and technological advancements aimed at further improving the efficiency, reliability, and scalability of DFIG-HVDC systems in the context of wind energy conversion.