Experiment and Analysis for Effect of Floating Conductor on Electric Discharge Characteristic

In this paper, we present a numerical analysis method for analyzing the discharge characteristic with the presence of a floating conductor. Space charges generated during the discharge process can accumulate on the surface of the floating conductor, or be emitted from its surface. An intensification of the electric field around the floating conductor is affected by those space species. Therefore, it is important to calculate the space-charge distributions considering the surface charge on a floating conductor because the discharge occurs at the floating conductor, which is placed around the cathode. An axial symmetry finite-element model is used to analyze this floating conductor discharge system, and Poisson´s equation is coupled with the hydrodynamic drift-diffusion equation to calculate space charge distributions. Fowler-Nordheim electron emission is employed for the boundary condition at conductor surfaces. The analysis results show the variation of the electric field due to the space charges and the surface charge density on the floating conductor. Experiments using corona generators are carried out, and the current data obtained show the space charge generated by the presence of a floating conductor.