Cooperative Control Strategy of Wind Turbine and SVG for Suppressing Feeder Overvoltage Due to DC Blocking

Transient overvoltages induced during DC transmission system faults (e.g., DC blocking) may trigger cascading wind turbine tripping or equipment damage in wind farms. However, existing various dynamic reactive power sources fail to distinguish the intrinsic differences in transient voltage variation characteristics and operate via autonomous responses, lacking coordinated control. To address this issue, this study first analyzes the impact of transient overvoltages in the sending-end system following DC blocking faults on the grid-side converters of wind turbines. Subsequently, a coordinated control strategy between wind turbines and Static Var Generator (SVG) is proposed to suppress sending-end overvoltages, which is formulated based on DC transmission capacity and transient voltage surge magnitudes. Finally, the effectiveness of this control strategy is validated through an electromagnetic transient simulation model. Simulation results demonstrate that the proposed strategy achieves significant suppression of transient overvoltage amplitudes.