Sparse Network Equivalent Based on Time-Domain Fitting

This article presents an approach for a network equivalent calculation for the analysis of electromagnetic transients in power systems. It is based on time-domain fitting and enforces some degree of sparsity while preserving the accuracy of the equivalent. The calculated equivalent is appropriate for direct interface with the rest of the system in time domain. A constrained least squares solution of the time-domain fitting equations is used to ensure accuracy at zero and 60 Hz. Results demonstrating the accuracy and computational efficiency of the method are presented.