Distribution network instantaneous current quick-break protection method based on short-circuit current quick estimation

The invention provides a distribution network instantaneous current quick-break protection method based on short-circuit current quick estimation. The method comprises the following steps: S1, calculating to obtain a corresponding setting current operating value; s2, sampling the three-phase current of the feeder line to obtain a sampling value sequence of the three-phase current; s3, judging whether one phase of current in the three-phase current meets a specified condition or not, and if yes, continuing to carry out the step S4; if not, returning to the step S2; s4, fast estimation of the effective value of the short-circuit current is realized based on a least square fitting algorithm, and an amplitude error level index is obtained; s5, correcting the setting current operating value in the step S1 by using an amplitude error level index; and S6, obtaining a fast instantaneous current protection action criterion. According to the method, on the premise that the reliability of protection action is not reduce