Real-time digital simulator of the electromagnetic transients of transmission lines with frequency dependence

A reliable and accurate real-time digital model for the time-domain computation of the electromagnetic transients of a power transmission line taking the frequency dependence into account has been developed and tested. The model provides a more accurate transmission line model which may replace the traditional pi-section networks in TNA-type physical components/hybrid simulators. The simulator is based on Marti´s time-domain formulation, which is adopted in the EMPT program. Improvements are made to speed up the calculation to realize real-time digital simulation. It obtains the electromagnetic transient performance of an unbalanced three-phase line in real time. Sample results of a single line to ground short circuit on an open-ended three-phase transmission line are presented. The real-time digital simulator results are verified for accuracy by simulating the same system, offline, on the EMTP program