Two-Frequency Voltage Flicker Estimation using Fuzzy Logic

H.M. Al-Hamadi (Kuwait)


Power quality, Voltage flicker, Kalman Filter, Multiple flicker and Fuzzy logic.


One of the crucial power quality problem is the voltage flicker. It is normally caused by rapidly occurring voltage fluctuations caused by sudden and large increases in the load current. This paper presents tracking technique of two voltage flicker signals occurring in electric power systems. A voltage flicker model consisting of two distinct flicker frequencies, amplitudes and phases is used for estimating the flicker signals. A discrete time linear dynamic state space model is adapted for Kalman filter to estimate the flicker parameters. Kalman filtering technique in conjunction with fuzzy rule-based logic are used to estimate the instantaneous voltage flicker magnitudes, frequencies and phases of the two flicker signals. The system and measurement covariance matrices are tuned up using a set of fuzzy logic rules to adjust their noise levels.

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