Modeling the influence of corona discharge on High-Voltage surges propagating along Transmission-Lines using TLM

Abstract

The effects of corona discharge on High-Voltage (HV) surges propagating on a single-wire transmission-line are demonstrated using the Transmission-Line Modeling technique (TLM). In particular, the effects can be demonstrated around a wire represented by short-circuited nodes and also using an Embedded-Wire Symmetrical Condensed Node (EW-SCN). The latter is seen to be ideally suited for adaptation necessary to incorporate such parameters relevant to corona inception. Calculations are based on a mathematical model proposed by Cooray (2000), that uses changes in voltage and charge density to describe corona, and a simplified model for corona simulation proposed by Thang et al (2012) that uses the addition of conductance to a FDTD mesh to obtain the desired result. The adaptations to the EW-SCN remain loyal to the transmission-line equations derived by Cooray and Neethayi (2008) that accurately describe the changes on a line in various representations e.g. dynamic capacitance accompanied with a dynamic conductance.