Transformer reclosing short-circuit impact current calculation method and system

The invention discloses a transformer reclosing short circuit impact current calculation method and system. The method comprises the following steps: determining a transformer reclosing short-circuit current calculation single-phase equivalent circuit; determining the current flowing through the transformer before the fault; inputting equivalent circuit parameters, system equivalent impedance seen from a port, power supply parameters and transformer equivalent impedance; judging whether the fault line has double circuits on the same tower or not, if the fault line has double circuits on the same tower, inputting the induced voltage at the fault point, and inputting the line equivalent impedance; setting the grounding impedance of the current fault point, and solving the reclosing short-circuit impact current of the transformer according to the current flowing through the transformer before the fault and based on the equivalent circuit parameters, the system equivalent impedance seen from the port, the power s