Abstract: Most of China's existing low-voltage distribution systems adopt low current grounding methods, with single-phase grounding faults accounting for a higher proportion of system failures. This article analyzes the changes in power data recorded by intelligent energy meters in the background and the relevant laws when a fault occurs on an overhead power distribution line through a grassland fire. By analyzing software, the backend data from smart energy meters is extracted, theoretical analysis and simulation experiments were used to verify the cause of the fire, combined with on-site inspections, investigation inquiries, video analysis and data analysis. The results show that the changes in data parameters recorded by the intelligent energy meter in the background are consistent with the changes in power parameters when a single-phase grounding fault occurs on overhead lines. Based on the method, further analyzing the actual fault situation of the line, and combining with other evidence, can provide a new approach for investigating the causes of fires caused by single-phase grounding faults on overhead lines.

Key words: fire investigation, single phase ground fault, smart energy meters, grassland fire