Electric corona discharge simulation in the hyperbolic point - ground plane configuration

The paper presents an algorithm to simulate the electric corona discharge in the hyperbolic needle ground plate configuration. The boundary conditions for the space charge density are derived from the direct ionisation criterion. This technique doesn´t rely on the Kaptzov hypothesis and can be used for any shape of the electrode. The proposed technique has been compared with two approximate ones: one based on Peek´s formula for the Laplacian electric field, another uses mechanically the Peek formula for the cylindrical wire, but replaces the wire radius with the surface curvature radius. The differences between all three approaches are negligible for small corona currents; they are noticeable, but still small, for higher currents.