Three-phase-to-ground Fault and Its Impact on Voltage Magnitude

According to growth of electricity demand and the increased number of non-linear loads in power grids, providing a high quality electrical power should be considered. In this paper voltage sag of the power quality issue is studied. Voltage sag due to power system fault,three-phase-to-ground is created in distribution line model, their effect on the voltage magnitude variation by varying fault resistance for each phase are examined. A simple and practical method is proposed for voltage sag detection, by calculating RMS voltage over a window for particular time period. The case study contains a single-machine including distribution line, which is simulated in MATLAB/Simulink environment.