To address the bottlenecks in single-phase grounding fault disposal

including the low accuracy of traditional station-end fault line selection devices

prolonged average disposal time

and difficulties in detecting high-resistance/intermittent faults

a precise disposal method based on primary-secondary coordination and multi-source verification is proposed. This method innovatively establishes a three-tier technical framework: Firstly

a differentiated dynamic setting model is established. Based on the neutral point grounding method(ungrounded

arc suppression coil grounded) and line parameters(cable

overhead line length)

the zero-sequence current reference value is derived via Kirchhoff's Current Law. By combining transient process analysis

protection setting values are dynamically generated

thereby resolving maloperation issues caused by empirical setting values. Secondly

the master station functionality is enhanced to support rapid decision-making. The four-remote point list is optimized by adding zero-sequence voltage and zero-sequence current remote measurements

and a "Single Command-Multiple Response" waveform transmission mechanism is established with the time reduced from 20 minutes to 1 minutes. An online setting values management module is developed to ensure consistency in multi-source verification. Finally

multi-source spatiotemporal topology verification is achieved by integrating the substation fault line selection device and distribution network terminal

while incorporating traveling wave positioning technology and wide-area synchronous intelligent sensors. Combined with the zero-sequence mutation quantity ratio criterion

this enables spatial topology verification between in-station line selection and out-station segment selection. The 200 faults simulation verification shows that under the transition resistance condition of 0~20 kΩ

the positioning accuracy

high-resistance fault detection rate

and average handling time of this method have significantly improved compared with the traditional method. This method resolves the problem of information isolation in distribution networks through resource integration and logic transformation

thereby providing a standardized technical pathway for high-reliability power supply.