Wavelets an Hilbert Transform methods for detection of voltage dips and micro interruptions

In electrical energy power network, disturbances can cause problems in electronic devices therefore their monitoring is fundamental in Power Quality field both to properly dimension protections and to calculate compensations in case of malfunction of the apparatus. In this paper we address the problem of disturbances estimation by using two different signal processing methods such as Wavelets processing and Hilbert Transform (HT). This last is employed as an effective technique for tracking the voltage in distribution systems. The mathematical simplicity of the proposed technique, compared with the commonly used algorithms from the literature, renders them competitive candidate for the on-line tracking of disturbances. The accurate tracking of the HT facilitates its implementation for the control of disturbances mitigation devices. Simulation results are provided to verify the tracking capabilities of the HT and to evaluate its performance as pre-processing for an embedded system. Two algorithms have been tested on voltage dip under different conditions of  noise and voltage harmonic distortion (THD) realizing a comparison between them that shows that the Hilbert Transform can be used as a valid methodology for this type of phenomena.

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