Energy Based Virtual Damping Control of FB-MMCs for HVDC Grid

Full-bridge submodule-based modular multilevel converters (FB-MMCs) have attracted wide attention due to the dc fault blocking capability. However, of FB-MMC can only suppress its terminal current, while currents may still circulate along with meshed network. To address this issue, energy-based virtual damping control is proposed, where current regulated follow voltage in event a fault. The is, thus, controlled as resistor actively absorb residual energy network and quickly potential circulating currents. This enables fast isolation using switches and, thereby, recovery after isolation. time significantly reduced from around 120 ms simply being blocked 50 conventional method 15 ms. validity proposed verified three-terminal