AN EFFICIENT RECURSIVE SCHEME FOR THE SIMULATION OF OVERVOLTAGES ON MULTIPHASE SYSTEMS UNDER CORONA

In the present work an efficient recursive scheme that was previously described and tested in single-phase transmission lines is extended fo r multiphase systems. The scheme uses frequency domain modal theory te chniques to obtain an independent solution for each multiphase line se gment with frequency dependent parameters. The compensation method is then applied for a combined solution of the voltage profile at each se ction and its associated ''corona branch''. The entire multiphase line is treated as a single nonlinear element by the EMTP. Simulations of field tests on an actual line under corona are presented and compariso ns are made with the previous implementations.