• An adaptive hybrid synchronization control is proposed for DC voltage-controlled MMC. • Enabling MMC wide-SCR operation and FRT via adaptive adjustment. • Parameter design principles and comparative simulation results are provided. With the increasing integration of large-scale offshore wind power, grid frequency and voltage stability issues are becoming more pronounced. Conventional control strategies for voltage source converter based high voltage direct current (VSC-HVDC) systems typically fail to provide active support to the receiving-end grid. This paper proposes a novel grid-forming control with enhanced active grid-support capability for offshore wind power VSC-HVDC systems. In the proposed scheme, the receiving-end converter implements hybrid synchronization control. This hybrid synchronization control flexibly integrates grid-following and grid-forming control through an adaptive coefficient, effectively enhancing the inertia and damping within the synchronization control loop, thereby improving the system’s transient stability performance. To maintain the voltage-source characteristics of converters during grid faults, a virtual impedance-based fault current limiting control method is proposed, with comprehensive investigation of its impact on system stability. Moreover, parameter design guidelines and comparative studies with other hybrid controls are provided. Finally, the effectiveness of the proposed control methodology is validated through PSCAD/EMTDC models. Simulation results verify that dynamically adjusting the adaptive coefficient ensures system stability under various disturbances and facilitates seamless AC fault ride-through.
Gan et al. (2026) studied this question.