
549
8
Problems and Application Limits
of Numerical Simulations
Because the electromagnetic transients program (EMTP) is based on circuit
theory assuming transverse electromagnetic (TEM) mode propagation, it
cannot give an accurate solution for a high-frequency transient that involves
non-TEM mode propagation. Additionally, the EMTP cannot deal with a cir-
cuit of unknown parameters. A numerical electromagnetic analysis (NEA)
method, on the other hand, can deal with a transient associated with both
TEM and non-TEM mode propagations. Furthermore, it requires no circuit
parameters. However, this method results in numerical instability if the ana-