Identification of corona parameters on overhead power lines in case of direct lightning strikes

Some problems of lightning overvoltage simulations for transmission lines with nonlinear corona model were presented in our previous papers. Obtained transients for relatively large peak values of subsequent lightning returnstroke currents, carried out by application of EMTP-RV, showed that nonlinear models of back-flashover and ZnO arresters work properly, while the corona model implemented in EMTP-RV gives some instabilities during simulations. A new approach using transfer functions for the linear part of the corona model is tested in the paper. The high efficiency System Identification Toolbox built in Matlab package is used during analysis of transfer functions. Obtained results show some possibilities of modeling of nonlinear elements using control devices in EMTP-RV simulator.