Study on the Influence of Lightning Current Waveform on the Impulse Characteristics of Grounding Grid

Lightning strikes on power plants and substations will affect the safe and stable operation of the grounding system. In order to improve the safety and stability of grounding system, it is necessary to study the impulse characteristics of grounding grid under different lightning current waveforms. Based on CDEGS, this paper builds the grounding grid model, and analyzes the corresponding relationship among the maximum ground potential rise (GPR), power frequency impedance, impulse impedance and impulse coefficient at different locations of the grounding grid under different lightning current waveforms. The results show that the peak time of different lightning current waveforms is different under the same duration; the maximum ground potential rise (GPR), power frequency impedance, impulse impedance and impulse coefficient corresponding to different lightning current waveforms are quite different; The impulse characteristics of different lightning current waveforms at different grid locations are also quite different. The above conclusions are feasible in grounding design and lightning protection engineering.