J. Phys. IV France 07 (1997) C4-259-C4-270
Triggering of Negative CoronaM. Laan, P. Paris and V. Repän
University of Tartu, Institute of Experimental Physics and Technology, Tartu Tähe Str. 4, EE2400 Estonia
The parameters of both low-current and high-current modes of DC negative corona discharge are described. The experiments were carried out in point-plane gaps in stagnant media of pure nitrogen, nitrogen, ambient air and in a dust-free air flow. A number of different types of point electrodes were used, including points covered by layers of TiO2 and HfO2 of controlled thickness. An overview of different methods of the triggering of the high-current mode is given. Discharges were initiated using x-ray radiation, laser radiation, UV radiation from different sources, and flux of positive ions. The correspondence of the model of dielectric switching mechanism as the triggering mechanism of high-current mode to the experimental results is discussed. Besides, the possible mechanisms limiting the repetition rate of Trichel pulses at its lower values (< 104 s-1) are analysed.
© EDP Sciences 1997