A Modified Multiport Two-Layer Network Equivalent for the Analysis of Electromagnetic Transients

This paper presents a modified two-layer network equivalent (M-TLNE) that provides a simpler surface layer compared to the original two-layer network equivalent (TLNE) without scarifying accuracy. The M-TLNE further reduces computational time which is of significance for statistical analysis and real-time simulation of electromagnetic transients. The MTLNE is simple, inherently stable, and is adequately accurate for practical applications. This paper also presents a generalized methodology for developing the proposed M-TLNE, based on a low-order vector fitting and a nonlinear least square minimization. The developed methodology is applicable to single and multiport network equivalents for both single and multiphase systems. Applications of the M-TLNE to single and multiport systems are also presented in this paper and the accuracy of the proposed M-TLNE is verified based on comparing the results with those obtained from detailed simulations of the system in the PSCAD/EMTDC simulation environment. A comparison of the M-TLNE with the original TLNE and the frequency-dependant network equivalent is also presented.