A comparative analysis applied to identification of partial discharges in dry-type transformers by inductive sensors and acoustic emission

• Grant number: 20/11035-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2020
• End date: April 30, 2021
• Field of knowledge: Engineering - Electrical Engineering
• Principal Investigator: Bruno Albuquerque de Castro
• Grantee: Vitor Vecina dos Santos
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

The interest in monitoring systems applied to power transformers has grown significantly in recent years and the motivation for the study comes from industry and academy sectors. Among several existing topologies, dry-type transformers have an important role in the electrical systems and industry. In this device, air circulation performs heat exchange and the insulation is composed by materials such as paper and epoxy resin. Some critical issues in the operation of the transformer can induce a slow degradation of the insulation materials, leading it to total failure. In the stages before the total failure, it is common to detect discharges in the insulation of the electrical machine. Among several methodologies to monitor discharges in transformers, acoustic emission (AE) and current analysis (CA) are characterized as promising non-destructive approach. In AE, piezoelectric transducers capture the acoustic waves emitted by the discharges. In CA, the electric current signature is analysed by using inductive sensors to identify the transients generated the failures. The objective of this work is to apply the discrete Fourier transform (DFT) and the Wavelet transform (WT) in the current and acoustic emission signals aiming to differentiate discharges in paper insulation and epoxy resins. In practice, each material requires different maintenance actions, and therefore, the differentiation of the types of failures is crucial to the improvement of this research field. In fact, besides to the scientific contribution of the proposal, this work has an international cooperation with the research group of the High Voltage Laboratory at the Technical University Federico de Santa Maria, in Santiago, Chile.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DE CASTRO, BRUNO ALBUQUERQUE; DOS SANTOS, VITOR VECINA; LUCAS, GUILHERME BERALDI; ARDILA-REY, JORGE ALFREDO; RIEHL, RUDOLF RIBEIRO; ANDREOLI, ANDRE LUIZ. A Comparative Analysis Applied to the Partial Discharges Identification in Dry-Type Transformers by Hall and Acoustic Emission Sensors. SENSORS, v. 22, n. 5, p. 17-pg., 2022-03-01. (20/11035-3)