Identification and coping approaches of sympathetic inrush current based on the station-area information of smart substation

Due to the absence of the effective identification and coping approaches of the sympathetic inrush current, the mal-operation of differential protection may be occasionally caused by sympathetic inrush current. In order to address this issue, the features of the sympathetic inrush current and the influence of the sympathetic inrush current on the differential protection are analyzed in detail in this paper. It is discovered that the second harmonic phase angle difference between the inrush current and the sympathetic inrush current are nearly 180°. Based on this, an identification and coping approaches for the sympathetic inrush current utilizing the information sharing between the smart substations is proposed in this paper. The effectiveness of this method is validated by the digital simulation and dynamic model experiment.