Dal Alert!

Receive alerts from Dalhousie by text message.


Transformers: Selection, Applications, Operation, Troubleshooting, and Maintenance

Upcoming Courses


This seminar will provide a comprehensive understanding of the various types of dry and oil-filled transformers. This seminar will focus on maximizing the efficiency, reliability, and longevity of this type equipment by providing an understanding of the characteristics, selection criteria, common problems and repair techniques, preventive and predictive maintenance.

This seminar is a MUST for anyone who is involved in the selection, applications, or maintenance of transformers because it covers how this equipment operates, the latest maintenance techniques, and provides guidelines and rules that ensure the successful operation of this equipment. In addition, this seminar will cover in detail the basic design, operating characteristics, specification, selection criteria, advanced fault detection techniques, critical components, dissolved gas analysis, and all preventive and predictive maintenance methods in order to increase reliability of the equipment and reduce the operation and maintenance cost.

This seminar will provide the following information for all types of transformers:

  • Basic Design
  • Specification
  • Selection Criteria
  • Sizing Calculations
  • Enclosures and Sealing Arrangements
  • Codes and Standards
  • Common Operational Problems
  • All Diagnostics, Troubleshooting, Testing, and Maintenance

Who should attend

  • Engineers of all disciplines
  • Managers
  • Technicians
  • Maintenance personnel
  • Other technical individuals (this seminar is suitable for individuals who do not have an electrical background)

Benefits to participants

Equipment Operation: Gain a thorough understanding of the operating characteristics of transformers

Equipment Diagnostics and Inspection: Learn in detail all the diagnostic techniques and inspections required of critical components of transformers

Equipment Testing: Understand thoroughly all the tests required for the various types of transformers

Equipment Maintenance and Troubleshooting: Determine all the  maintenance and troubleshooting activities required to minimize transformer downtime and operating cost

Equipment Repair and Refurbishment: Gain a detailed understanding of the various methods used to repair and refurbish transformers

Efficiency, Reliability, and Longevity: Learn the various methods used to maximize the efficiency, reliability, and longevity of transformers

Equipment Sizing: Gain a detailed understanding of all the calculations and sizing techniques used for transformers

Design Features: Understand all the design features that improve the efficiency and reliability of transformers

Equipment Selection: Learn how to select all types of transformers by using the performance characteristics and selection criteria that you will learn in this seminar

Equipment Enclosures and Sealing Methods Learn about the various types of enclosures and sealing arrangements used for transformers

Equipment Commissioning: Understand all the commissioning requirements for transformers

Equipment Codes and Standards: Learn all the codes and standards applicable for transformers

Equipment Causes and Modes of Failure: Understand the causes and modes of failure in transformers

System Design: Learn all the requirements for designing different types of transformer systems

Training methodology

The instructor relies on a highly interactive training method to enhance the learning process. This method ensures that all the delegates gain a complete understanding of all the topics covered. The training environment is highly stimulating, challenging, and effective because the participants will learn by case studies which will allow them to apply the material taught to their own organization.

Special feature

Each participant will receive a copy of the following materials written by the instructor:

  • Transformer Testing and Maintenance Manual (covering all the tests, maintenance activities, and protective systems required for all types of transformers - 250 pages)

Program outline

Day 1 - Transformers, Types and Construction of Transformers, Autotransformers, Transformer’s Characteristics, Transformer Windings, Transpositions, Impulse Strength, Transformer Components, Transformer Oil Testing, Dissolved Gas Analysis, Gas Detector Relays

  • Inductors, capacitors, alternating current, Faraday’s law, magnetic field, three-phase system
  • Machinery principles, magnetic behavior of ferromagnetic materials, energy losses in a ferromagnetic core, core losses, permanent magnets
  • Transformers, types and construction of transformers, impedance transformation through a transformer, analysis of circuits containing transformers, equivalent circuit in a transformer
  • Voltage regulation, transformer efficiency, transformer taps and voltage regulators, autotransformers, three-phase transformers, transformer ratings, inrush current, instrument transformers
  • Transformers’ characteristics, phase relationships, Star/Star connected transformer, basic materials, dielectrics, copper, iron, insulation, leakage reactance, core construction
  • Transformer winding configurations, basic transformer design concepts, transformer connections, wye winding configurations, phase shifts using clock notation, delta winding configurations, auto-transformer winding configurations, zigzag (interconnected star) winding configurations, combination of various winding configurations
  • Transformer windings, transpositions, continuously-transposed strip, impulse strength, thermal considerations, performance under short-circuit
  • Transformer components and maintenance, classification of transformers, dry transformers, oil-immersed transformers
  • Components of a power transformer, core, windings, nitrogen demand system, conservative tank with air cell, current transformers, bushings, insulation
  • Tap changers, Tapchanger mechanisms, single-compartment tapchangers, in-tank tapchangers, off-circuit tapchangers, tanks, connections and auxiliary plant
  • Oil preservation equipment, conservators, bushing connections, SF6 connections, cable box connections, tank-mounted coolers, separate cooler banks, water cooling, cooler control, layout of transformer compounds, galvanic anode, impressed current cathodic protection system
  • Types and features of insulation, reasons for deterioration, forces, cause of transformer failure
  • Transformer oil, testing transformer oil, causes of deterioration, neutralization number test, interfacial tension test, Myers index number, transformer oil classification system, methods of dealing with bad oil, gas-in-oil
  • Dissolved Gas Analysis, advanced detection of incipient fault conditions leading to all failure modes, oil collection, gas extraction, standards and guidelines governing dissolved gas analysis, gases in oil, transformer gas separation by gas chromatography, gas solubility coefficients in oil, partitioning, diagnosis, new guidelines for interpretation of Dissolved Gas Analysis in oil-filled transformers, basic gas ratio, indication/fault gas, fault types
  • Gas relay and collection systems, relief devices, interconnection with the grid

Day 2 - Transformer Component Selection, Tapchangers, Transformer Tests, Type Tests, Special Tests, Harmonics, Transformer Protection

  • Transformer Component Selection, tappings and tapchangers, tapchanger mechanisms
  • Transformer tanks, connections and auxiliary plant, oil preservation equipment - conservators, bushing connections, SF6 connections, cable box connections, tank-mounted coolers, separate cooler banks, water cooling, cooler control
  • Layout of transformer compounds
  • Transformer Quality Assurance, transformer testing during manufacture, transformer processing and dry-out, Final testing
  • Transformer Tests, Measurements, Calculations, and Evaluation Criteria
  • Transformer Routine Tests, Type Tests, and Special Tests
  • Routine Tests: measurement of winding resistance, measurement of voltage ratio and check of polarity and phase displacement, measurement of short-circuit impedance and load loss, measurement of no-load loss and current, dielectric tests, separate source AC withstand voltage test, induced ac voltage test, partial discharge measurement, tests on on-load tap-changers, open-circuit and short-circuit tests
  • Type Tests: temperature-rise test, lightning-impulse tests
  • Special Tests: switching impulse voltage test, measurement of dissipation factor (tan δ) and capacitance, measurement of zero sequence impedance(s), Determination of sound level, measurement of harmonics of the no-load current, measurement of insulation resistance, short-circuit withstand test, condensation test, condensation and humidity penetration test, low temperature test, heating-shock test at -5°C, heating-shock test at -25°C
  • Transformer protection, transformer protection overview, transformer failures
  • Differential characteristic, inrush inhibit during transformer energization, sensitive ground fault protection to limit transformer damage, overflux protection
  • Winding hot-spot temperature protection
  • Application capabilities, phase shift transformers, split-phase autotransformer
  • Typical applications of transformer protection relays