Binary classification of operating state of power transformers using Performance Index and Machine Learning Models

Authors
Keywords:
Classifier, Machine Learning, Performance Index, Power Transformer, Predictive Technique
Abstract

Power transformers are strategic and valuable assets in electrical systems, as their unexpected failures can lead to significant operational and financial losses for power sector companies and consumers. Although there have been advancements in monitoring their operational conditions, some methodologies still require specialized interpretation, lack standardization, or adopt models whose complexity can hinder integration with the usual operational practices of maintenance professionals. In this context, the objective of this work is to develop binary classifiers based on machine learning algorithms for fast and efficient prediction of the operational state of power transformers, labeled as Satisfactory or Unsatisfactory, using data derived from physicochemical tests, Dissolved Gas Analysis (DGA), and performance indices, based on real equipment samples. The methodology involves the development of supervised machine learning models, such as Random Forest, HistGradientBoosting, Balanced Logistic Regression, and XGBoost, implemented with stratified cross-validation. The results indicate that the classifiers can satisfactorily identify transformers in critical condition, even in a scenario with considerable data dispersion. Therefore, the proposed approach represents a promising tool for technical decision-making in preventive maintenance strategies, combining reliability, scalability, and ease of application in field environments.

Author Biographies
  1. Vinícius Faria Costa Mendanha, Federal University of Goiás

    Vinícius Faria Costa Mendanha nasceu em 19 de maio de 1998. Atualmente, é mestrando no Programa de Pós-Graduação em Engenharia Elétrica e de Computação da Universidade Federal de Goiás. Graduou-se em Engenharia Elétrica pela Universidade Federal de Goiás (UFG) em 2023. Em 2018-2019, integrou a Agremiação Politécnica da UFG, na área de Administração. Em 2019, ingressou no PET (Programa de Educação Tutorial) Engenharias Conexão de Saberes, realizando também Iniciação Científica. Estudou análise de sinais e fenômeno de Gibbs (2019-2020). Dedica-se ao estudo de Inteligência Computacional aplicada à área de manutenção de transformadores de potência e é membro da Equipe do Laboratório de Pesquisa em Engenharia de Alta Tensão - LAPEAT UFG. https://orcid.org/0000-0003-0982-9328

  2. André Pereira Marques, Federal University of Goiás

    André Pereira Marques nasceu em 25 de fevereiro de 1961 em Araguari, Minas Gerais, Brasil. Doutor (2018) e Mestre (2004) em Engenharia Elétrica pela Escola de Engenharia Elétrica, Mecânica e de Computação (EMC) da Universidade Federal de Goiás (UFG). Ele é Professor Titular no Instituto Federal de Goiás – Campus Goiânia (IFG) desde 1990, trabalhando nos cursos de Engenharia Elétrica, Engenharia de Automação e Curso Técnico em Eletrotécnica. Ele também é Gerente Técnico e proprietário da empresa APMarques Consultoria e Capacitação em Engenharia Elétrica desde 2019, especializado em estudos de carregamento e diagnósticos em transformadores de potência e é membro da Equipe do Laboratório de Pesquisa em Engenharia de Alta Tensão - LAPEAT UFG https://orcid.org/0000-0001-6641-7835

  3. Cacilda de Jesus Ribeiro, Federal University of Goiás

    Cacilda de J. Ribeiro nasceu em 8 de agosto de 1971 em Matão, São Paulo, Brasil. Doutora (2002) e Pós-Doutora (2004) em Engenharia Elétrica pela Escola de Engenharia de São Carlos, da Universidade de São Paulo. Atualmente, é professora titular na Escola de Engenharia Elétrica, Mecânica e de Computação (EMC) na Universidade Federal de Goiás (UFG), e Coordenadora do Grupo de Trabalho Mulheres nas Engenharias GTME EMC UFG e do Laboratório de Pesquisa em Engenharia de Alta Tensão - LAPEAT UFG. https://orcid.org/0000-0002-8725-3443

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Published
2026-03-11
Section
ENERGY
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Copyright (c) 2026 Mendanha, V. F. C., Marques, A. P., & Ribeiro, C. de J.

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How to Cite

Mendanha, V. F. C., Marques, A. P., & Ribeiro, C. de J. (2026). Binary classification of operating state of power transformers using Performance Index and Machine Learning Models. Brazilian Journal of Production Engineering, 12(1), 120-133. https://doi.org/10.47456/bjpe.v12i1.49144