EMTP transient modeling of a distance relay and a comparison with EMTP laboratory testing

A method to test the transient performance of a sampled-data relay is given. A model of one measuring unit of a digital relay is created on a personal computer. The simulations are compared with laboratory results obtained by applying digitally generated waveforms to the actual relay. Computer modeling of the digital relay is done within the models version of the Transient Analysis of Control System (TACS) subsection of the ElectroMagnetics Transient Program (EMTP). The input filter, analog-to-digital converter, Fourier fundamental frequency detector, and the relay measuring principle of one digital microprocessor-based relay are modeled. An actual 115 kV 150 mile long transmission line is simulated using the EMTP.<>