Substation arc extinguishing system

The utility model discloses an arc extinguishing system of a transformer station. The arc extinguishing system comprises a grounding transformer and an arc extinguishing coil. The power transmission line, the grounding transformer, the isolation switch, the arc suppression coil, the damping resistance box and the ground are sequentially connected. A tap of the arc suppression coil is connected with an on-load switch, and the on-load switch is connected with the microcomputer controller through a data line; the damping resistance box is connected with a microcomputer controller, and the microcomputer controller is electrically connected with a power transmission line through a zero sequence CT. According to the system, a grounding resistor is connected to a neutral point, when the system has a grounding fault, high impedance is provided for positive-sequence and negative-sequence current, low impedance is provided for zero-sequence current, grounding protection acts reliably, and then the neutral point is grou