Rapid tripping of a NH fuse using a power-flow controller with high-frequency current injection

The increasing integration of renewable energy sources, electric vehicles, and powerelectronics-interfaced devices in low-voltage distribution grids has increased grid utilization but reduced the available short-circuit capacity. The low short-circuit current challenges voltage stability but also conventional fuse-based protection. Although power-flow controllers and soft open points improve voltage regulation and thermal loading under normal operating conditions, their behavior during abnormal and fault conditions has received limited attention. This paper presents a protection-oriented control strategy for a compact direct-injection universal powerflow and quality controller (UPFC/QC) with wide operation bandwidth that enables rapid fuse tripping independent of the fundamental…