Analysis of Single-phase Short-circuit Current Suppression Measures at Converter Stations and Their Effects on Power System Reliability

Aiming at the issue that the single-phase short-circuit current at the 500kV side of Yibin and Fulong converter stations has exceeded the breaking capacity of breaker, the reason is analyzed and the measures are put forward to reduce the single-phase short circuit, including limiting the output of thermal power near field, converter transformers neutral grounding by small reactance and 500kV lines adding series reactors. The limiting effects of single-phase short-circuit current and the impacts on power grid equipment operation and power supply reliability of different measures are compared. Feasible suggestions for reducing single-phase short-circuit current and improving power grid reliability are given.