Improving computational efficiency of FD line model for real-time simulation of emts

This paper presents a reformulated and efficient version of the frequency dependent transmission line model (FDLINE) for achieving real-time simulations in a multiprocessor computer. This reformulated version of the FD-LINE model is based under the concept of state-space variables in a Norton equivalent circuit and the efficiency is improved with low order approximations through the vector fitting technique. The equations to interface the FD-LINE with state-space nodal solver are explained to solve electrical networks. Comparisons of transient response resolution between FD-LINE model with different fitting orders and CP-LINE model are presented for an open and short circuit line. Finally, the computational burden required for the FD-LINE model in a real-time simulator is provided for several fitting orders.