Electromagnetic Safety Assessment of Low-voltage Distribution System Buildings in Thermal Power Plants in Case of Lightning Strike

The low-voltage distribution system of thermal power plants has a large auxiliary power load and is vulnerable to electromagnetic influence, so its lightning protection is relatively complex. This paper takes Xishui Substation as the research object, and uses CDEGS software to build its buildings and grounding grid model, and calculates the shunt of lightning current in branch conductors, indoor magnetic field distribution and grounding grid potential distribution of thermal power plants when lightning strikes buildings. The results show that the shunt coefficient of the thermal power plant buildings basically meets the specification requirements. The lightning that strikes buildings will not cause harm to indoor equipment near the middle. Lightning flowing through buildings and leaking into the ground will threaten its low-voltage distribution system with ground potential counterattack. This provides data basis for electromagnetic safety assessment of low-voltage distribution system in thermal power plants, and is of great significance for improving reliable operation of low-voltage distribution system in thermal power plants.