Power distribution network phase-to-phase fault isolation method and system based on magnetic control switch rapid opening

The invention discloses a power distribution network phase-to-phase fault isolation method and system based on magnetic control switch rapid opening. The method comprises the following steps: judging whether a phase-to-phase fault occurs or not; if the two-phase fault occurs, solving extreme points, meeting preset conditions, of the currents of any two phases of the fault at the same time; judging whether a difference value between the extreme point and the power frequency cycle sampling fault point is greater than a preset threshold value or not; if the first current amplitude is greater than the preset threshold value, constructing a first current sampling sequence, and judging whether the first current amplitude is greater than an overcurrent protection setting value or not; if the overcurrent protection setting value is greater than the overcurrent protection setting value, judging that overcurrent logic is met; solving a three-phase voltage amplitude, and judging whether the voltage amplitude of any two