E-lesson

TCA I course – e-lesson#1: Reviewing transformer data and background

Basic level Tuesday, 3 March 2026, 2:00 PM TZ Europe/Zagreb
Basic level

Hosted by: Transformer Academy

The first lesson of the Transformer Condition Assessment I (TCA I) course introduces the fundamental concepts, objectives, and methodology behind structured transformer condition assessment.The session explains why condition assessment is essential for ensuring the long-term reliability of power transformers, which represent one of the most critical and expensive assets in power systems. Drawing on industry experience and established standards, the lesson outlines how utilities, asset managers, and engineers evaluate transformer health in order to detect potential problems before they lead to failures. Participants are introduced to the key principles defined in international standards and guides, particularly those developed by IEEE, which provide structured approaches for transformer maintenance, testing, and condition evaluation. The lecture also presents the overall methodology of transformer assessment, including the role of visual inspection, maintenance records, diagnostic testing, and engineering analysis in determining transformer condition and operational risk.Special attention is given to practical maintenance strategies, such as the importance of preventive inspections, monitoring transformer accessories, and identifying early warning signs through techniques such as dissolved gas analysis (DGA). These methods form the first step in detecting internal faults and degradation mechanisms that may develop during transformer operation.

By establishing the key terminology, assessment criteria, and inspection philosophy, this introductory lesson provides the conceptual foundation for the more advanced diagnostic methods that will be covered in subsequent sessions of the course.

 

Key topics covered

  • Definition and objectives of transformer condition assessment
  • Role of international standards (IEEE, IEC, CIGRÉ) in assessment methodology
  • Importance of maintenance planning and preventive inspection
  • Visual inspection and monitoring of transformer components
  • Introduction to diagnostic methods such as dissolved gas analysis (DGA)
  • Overview of online and offline transformer testing approaches
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About the author

Marcos Ferreira

Marcos Ferreira

Marcos  Ferreira  is  an  Electrical Engineer with 35+ years of diversified corporate experience in designing, managing, and coordinating projects in transmission, distribution, communications, in the State of Massachusetts, Texas, Ohio, Oregon, Washington and California as well as all Canadian Provinces. He has worked on substation HV equipment new installation and replacement (e.g., transformers,  circuit breakers, etc.) based on standard design including system protection, and commissioning. During his career  he worked as senior maintenance engineer for Bonneville Power Administration and senior field engineer for Doble Engineering specialized on testing substation HV  equipment and provided technical support. Marcos Ferreira has taken on the role of a project manager at United States Beale Air Force Base, North of California, as part of Civil Engineer Squadron team. Furthermore, most recently Marcos Ferreira worked for Quanta Technology, LLC, as Principal Advisor, part of Asset Management Team. Most recently, worked for FEMA and then, Virginia Transformer as the present time.

Marcos Ferreira has been involved in IEEE Transformer Standards Committee Meetings for the past 25 years. He has been contributed as Chair for Working Groups (C57.152, Transformer Field Tests Guide and C57.140, Transformer Reconditioning and Evaluation. Also, for more than five years as Vice-Chair of Standard Subcommittee.