Fault indicator and power distribution network line fault judgment method

The invention relates to the technical field of power electronics, and discloses a fault indicator and a power distribution network line fault judgment method, and the fault indicator comprises an edge calculation unit, a collection unit and an acquisition unit. The edge calculation unit is installed at the bus, can collect the zero-sequence voltage of the bus, accurately identifies the line grounding fault, and supports the collection of the data of the same bus collection unit. When a single-phase earth fault occurs in a line, the edge calculation unit detects zero-sequence voltage out-of-limit, identifies the earth fault and sends a wave recording triggering command to the collection unit, and after receiving the wave recording command, the collection unit calls and reads electric field and current data collected and stored by the collection unit at the fault moment and synthesizes a waveform. And the collection unit uploads the synthesized waveform to the edge calculation unit, and the edge calculation un