Sigre 2015. — 6 с.
General Electricity Company, LibyaTraditional analysis of protection system performance involves comparing phases (currents, voltages ,impedances , etc ) against theoretical characteristics of the relay. In the case of a distance protection, a complex R/X plane impedance characteristic is normally used for this purpose. This approach is fairly simple and requires only knowledge of magnitude and phase of currents and voltages. In certain situations when secondary waveforms are distorted by higher-order or sub-harmonics, however it is possible to have an effect on the performance of the protection device.
The work presented herein is concerned with the impact of the transformer magnetizing inrush phenomena and power swing on the performance of the impedance-based protection relay. The study demonstrates how the relay 7SA511 respond to the distorted waveforms and power system disturbed.
