面向大规模新能源馈入受端电网的柔性直流主动支撑技术研究进展OA

With the continued advance of China's carbon peaking and carbon neutrality goals and the rapid development of high-voltage direct-current transmission based on the modular multilevel converter(MMC-HVDC),receiving-end power grids are experiencing unprecedented changes in dynamic characteristics.A rising share of power-electronic equipment makes them vulnerable to rapid frequency decline,voltage fluctuations,and multi-band oscillations after dis-turbances.As a key technology for long-distance power transmission and regional renewable-energy integration,MMC-HVDC is crucial for active frequency and voltage support and oscillation control.Addressing these operational challenges,this paper analyzes the evolution mechanisms and instability risks of receiving-end grids from the perspec-tives of frequency,voltage,and resonance stability,and reviews progress in MMC-HVDC active support for inertia and frequency regulation,voltage,and damping.Then,this paper summarizes the coupling and common constraint boundaries among these three support requirements in terms of characteristic time scales,converter current-margin allocation,and control/communication delays.Finally,this paper discusses challenges and key issues at the grid,MMC-HVDC system,and equipment levels,providing theoretical and technical guidance for a coordinated multi-level support mechanism en-compassing the grid,MMC-HVDC,and equipment.