FAULT SWITCH CONFIGURATION AND CLEARING METHOD IN FLEXIBLE DC CONVERTER STATION

A fault switch configuration and clearing method in a flexible DC converter station, the flexible DC converter station is configured with a grid side switch (QF1) and a valve side phase-split switch (QF2) in the converter station. When a fault occurs, a faulty phase and a non-faulty phase are detected and identified by means of differential protection or low voltage overcurrent. An alternating current (AC) zero crossing condition is created by means of firstly turn off the non-faulty phase valve side phase- split switch (QF2) and the grid side switch (QF1), thereby cutting off the faulty phase, disconnecting the connection between a power supply and a fault point, and achieving the clearing for faults. The described fault-clearing method is simple and practical, highly reliable, and connection between the fault point and the power supply is quickly and effectively cut; converter station equipment is effectively protected, and further expansion of the fault is avoided.