Abstract:An impulse current generator is used through burying grounding grid to investigate the impulse characteristics with different rise time of injected current,different injection point of grounding grid by the use of field experiments.The results show that impulsive discharging efficiency is closely related to the rise time of injected current and the injection point.Impulse current injected from the grounding grid center,which can effectively reduce the potential of ground point,improves the impulsive discharging efficiency of the grounding grid.