Modeling of Acoustic Emission Signals Generated in On Load Tap Changer

Abstract

The paper deals with mathematical modeling of acoustic emission signals which are generated in on load tap changers. In power engineering area acoustic emission method is commonly used for diagnosis purposes. Authors in their research works apply it for detection of defects occurring in on load tap changers, which are important elements of power transformers. The acoustic emission method is based on measurements performed by use of wideband piezoelectric transducers that are mounted on transformer tank surface. The registered signal is then analyzed in the time, frequency, and timefrequency domains or is evaluated with computer expert systems for diagnosis purposes. Depending on indicators device technical condition can be determined. The contribution given by the authors in this paper is proposal of a mathematical model, which describes envelope of the measured acoustic emission signal.

Application of a mobile system in diagnostics of power capacitors using the acoustic emission method

“…Accordingly, the following diagnostic methods for insulating systems have been developed: invasive and non-invasive electrical methods [3][4][5][6][7][8][9][10][11] ; gas chromatography; wideband methods: UHF (ultra high frequency) or VHF (very high frequency) [12][13][14] ; the acoustic emission (AE) method [15][16][17][18][19][20][21][22][23][24][25] ; and optical spectrophotometry [26][27][28][29][30] . The subject area of this paper covers improving the AE method applications.…”

“…Considerable interest in the AE method was observed in the 1960s, when the method was applied in studies of the PD phenomenon [31][32] . Studies involving perfecting the AE method applied to diagnose high-voltage insulating systems in power transformers have been carried out by many scientific and research centres [15][16][17][18][19][20][21][22][23][24][25][33][34] . However, diagnostic measurements related to applying the method for insulating systems in power capacitors are much narrower in scope.…”

An expert system for acoustic diagnosis of power circuit breakers and on-load tap changers

“…A PhD thesis has been presented in Adelaide University by analyzing the vibro-acoustics of transformers and their application in the condition monitoring of power transformers (Wang, Eng, & Eng, 2015). A study for mathematically modeling the acoustic signal of OLTCs has been presented in (Cichon, Borucki, & Wotzka, 2014) and methods for extracting characteristics of the acoustic signals generated by OLTCs during operation have been analyzed by (Cichoń & Frącz, 2012). A method for analyzing the arching process in OLTCs based on acoustic signals has been discussed in (Bhuyan & Mor, 2014).…”

Application of the Acoustic Emission Method for Diagnosis of On-Load Tap Changer

“…An example of a comprehensive approach to the analysed issue is the OLTC monitoring system, presented in (Cichoń et al, 2012;2014 Wang et al, 2008). Currently, the main direction of further research studies on this subject matter is the development of effective and noninvasive methods.…”

“…Therefore, there is a possibility to record AE signals by using a piezoelectric transducer attached to the external part of the tank. These obtained AE signals provide useful information which can successfully describe the operation of both the power switch and the selector (Cichoń et al, 2012;2014;2015). The acoustic signal generated during the OLTC switching cycle contains information about two diagnostic areas of the power switch.…”