Effect of the Applied Voltage and the Active Electrode Geometric Parameters on the Characteristics of Negative Corona Discharge

The current pulses shape of negative corona discharge are very regular in electronegative gases. These pulses bear the name of the one who first studied them, Trichel. The repetition frequency, the current amplitude and the mean current of Trichel pulses are affected by many parameters like: the curvature radius of the high voltage electrode, the applied voltage and the electrode-gap. In this work, we present an experimental study of the negative corona discharge carried out on a tip-plane electrode system. The tests were carried out under different experimental conditions to illustrate the effect of each parameter. The obtained results show that the repetition frequency of pulses and the mean current increase with the applied voltage and they decrease with the electrode-gap and the curvature radius of the active electrode. The experimental results were processed with numerical fitting to derive a numerical model and compare it to theoretical models.