Comparison of Voltage Sag and Swell Detection Algorithms In Power System

Abstract:- Power quality issues have been a source of major concern in recent years due to extensive use of power electronic devices and non-linear loads in electrical power system. Voltage sags and swells is a common power system disturbance, usually associated with power system faults. Therefore the effective detection of voltage sags and swells event is an important issue for both voltage sag and swell analysis and mitigation. There are several detection methods for voltage sags and swells such as RMS voltage detection, peak voltage detection, and Fourier transform methods. The problem with these methods is that they use a windowing technique and can therefore be too slow when applied to detect voltages sags for mitigation since they use historical value, not instantaneous value which may lead to long detection time when voltage sag has occurred. A novel algorithm require for voltage sag detection. The algorithm can extract a single non-stationary sinusoidal signal out of a given multi component input signal. The algorithm is capable of estimating the amplitude, phase and frequency of an input signal in real time. No complex mathematics is required for implementation of the algorithm. It is compared to other methods of sag detection and same procedure for swell also. Keywords:- Power quality, peak voltage detection, rms voltage detection, voltage sag. I