Study on Time Domain Simulation Model for Lossy Frequency-Dependent Single Transmission Line

The traditional Bergeron model is a lossless distributed parameter line model, which can take the loss into account by adding lumped resistance, but the influence of the frequency-dependent characteristics of the line parameters cannot be considered. For this problem, the characteristic impedance of the Bergeron model is fitted by Pade approximation and then substituted by parallel Foster models; the transfer function of the Bergeron model is fitted by Prony approximation, thereby establishing the time domain Bergeron model of transmission line that considers line loss and frequency-dependent effects. Finally, taking the lossy and frequency-dependent single-conductor transmission line as an example, the proposed model is used to compute the line's response of the transmission line under step excitation at time domain, and the results are compared with the results of the EMTDC/PSCAD. The results show that the calculation results of the two methods are in good agreement, which verifies the proposed model.