Abstract: With the development of the power grid, the original 10kV power supply long-distance heavy-duty lines have gradually been transformed into 35kV single incoming single transformer substations. When designing such substations, preventive measures should be taken to prevent the rise of neutral point voltage caused by lightning intrusion waves. For 35kV transformers (YD11) that have already been put into operation, effective measures should be taken to avoid equipment damage and unplanned shutdown caused by lightning intrusion waves.