ABSTRACT
Because the electromagnetic transients program (EMTP) is based on a circuit theory assuming transverse electro-magnetic (TEM) mode propagation, it cannot give an accurate solution for a high-frequency transient which involves non-TEM mode propagation. Also, the EMTP cannot deal with a circuit of unknown parameters. On the contrary, a numerical electromagnetic analysis (NEA) method can deal with a transient associated with both TEM and non-TEM mode propagation. Furthermore, it requires no circuit parameter. However, it results in numerical instability if the analytical space, the boundary conditions, the cell size, etc., are not appropriate. Also, it requires a large amount of computer resources, and existing codes are not general enough to deal with various types of transients, especially in a large network.
