Modeling of Frequency Dependent Losses of Transmission Lines with VHDL-AMS in Time Domain

A time domain model of a three conductor transmission line considering frequency depended losses, e.g. skin-effect, for the modeling language VHDL-AMS was developed. The calculation features of VHDL-AMS were considered and flexible and efficient approximations for the frequency dependent propagation and admittance functions could be implemented. The model can be used for linear and non-linear time and frequency domain simulations. It forms a basis for EMC extensions that can be implemented using the developed approximation techniques. Modern standardized modeling languages like VHDL-AMS (very high speed integrated circuit hardware description language - analog and mixed signal) have the important advantage that growing model libraries permit fast creation of complex simulation models. Exchange and extension of models is easily possible. After a short introduction and presentation of the theory used for modeling, application examples are shown. The developed model is compared to measurement results and to a lossless multiconductor transmission line model. The validity of the implemented VHDL-AMS model is proved.