Observations of corona point discharges from grounded rods under thunderstorms

We investigated features of corona point discharges when a grounded conductive rod is subject to high background electric field. In the laboratory, voltage applied an upper plate in plane-to-point experiment, and are observed from using ultraviolet camera photosensor. The current measured shunt resistor, transformer, impedance ammeter. have found that pulses fast rise time (tens nanoseconds) slow decay (hundreds nanoseconds). For initial stage discharges, above certain threshold, frequency increases with applied. field, one sensor coupled rod, 1.5 m roof, was installed site located at altitude 2525 sea level. same laboratory recorded during periods field enhancement caused by movement charged clouds or lightning activity near sensor. specific installation, correlated ambient 250 away. To best knowledge authors, this first which such correlation made for outdoor measurements, seeing other works correlate average flow. Pulses positive were no longer magnitude lower than 1.8 kV/m negative more atypical presented higher about 3.8 kV/m. This study relevant understanding production space charges structures, as wind turbine blades, towers, buildings general.