Introduction

Power transformers are indispensable assets within any electrical grid, serving as the critical links that enable efficient and reliable transmission and distribution of electricity across various voltage levels. Their long operational life and significant capital cost necessitate a deep understanding of their intricate design principles, rigorous testing methodologies, and proactive maintenance strategies. As grids become more complex, integrating diverse generation sources and facing evolving load demands, the performance and longevity of transformers are paramount for system stability and operational continuity. Power Transformer Design, Testing & Maintenance encompasses a broad spectrum of engineering disciplines, ensuring that these vital components can withstand electrical, thermal, and mechanical stresses throughout their lifecycle. Without a comprehensive grasp of Power Transformer Design, Testing & Maintenance, utilities and industrial operators face increased risks of costly outages, premature asset failures, and suboptimal grid performance, undermining the reliability of the entire power delivery infrastructure. This comprehensive training course focuses on equipping professionals with the expertise to master Power Transformer Design, Testing & Maintenance.

This training course is meticulously designed to empower electrical engineers, maintenance managers, testing technicians, procurement specialists, and asset managers with the theoretical understanding and practical tools necessary to excel in the lifecycle management of power transformers. Participants will gain a deep understanding of transformer construction and materials, explore the fundamental principles of transformer design for various applications, learn about the international standards governing factory and site acceptance testing, and acquire skills in implementing effective condition monitoring and diagnostic techniques. The course will delve into topics such as insulation systems, short-circuit withstand capability, transient phenomena, dissolved gas analysis (DGA), partial discharge testing, refurbishment strategies, and the latest trends in intelligent transformer monitoring and digital twins. By mastering the principles and practical application of Power Transformer Design, Testing & Maintenance, participants will be prepared to optimize asset performance, extend operational life, minimize downtime, and contribute significantly to the reliability and economic efficiency of power systems.

Duration: 10 Days

Target Audience

• Electrical Engineers (Utility, Industrial, Consulting)
• Substation Maintenance Engineers and Technicians
• Power System Asset Managers
• Testing and Commissioning Engineers
• Design and R&D Engineers for Transformers
• Procurement and Quality Control Specialists
• Plant Electrical Engineers
• Reliability and Condition Monitoring Specialists
• Project Managers for Substation Projects
• Technical Sales Professionals for Transformer Manufacturers

Objectives

• Understand the fundamental principles of power transformer operation and construction.
• Learn about the various types of power transformers and their applications.
• Acquire skills in interpreting transformer specifications and design parameters.
• Comprehend techniques for calculating key electrical characteristics (e.g., impedance, losses).
• Explore strategies for designing transformer insulation systems and managing thermal performance.
• Understand the importance of short-circuit withstand capability and design considerations.
• Gain insights into international standards for transformer testing.
• Develop a practical understanding of routine, type, and special tests for transformers.
• Learn about various on-site diagnostic testing methods (e.g., DGA, insulation resistance).
• Master the principles of condition monitoring and predictive maintenance for transformers.
• Acquire skills in interpreting test results and diagnostic data for fault identification.
• Understand the causes of transformer failures and effective mitigation strategies.
• Explore transformer maintenance practices including oil purification and tap changer servicing.
• Develop proficiency in managing the remaining life of aging transformer fleets.
• Prepare to optimize the performance and extend the lifespan of power transformers.

Course Content

Module 1: Fundamentals of Power Transformer Operation

• Basic principles of electromagnetic induction.
• Ideal vs. real transformers: equivalent circuits and phasor diagrams.
• Voltage and current ratios, impedance, and turns ratio.
• Transformer losses: no-load (core) and load (copper) losses.
• Efficiency calculations and load considerations.

Module 2: Power Transformer Construction and Components

• Core construction: laminated steel, amorphous metal, core types (shell, core).
• Winding arrangements: concentric, interleaved, disc, helical.
• Insulation materials: oil, paper, pressboard, insulating gases (SF6, natural esters).
• Cooling methods: ONAN, ONAF, OFAF, ODAF, water cooling.
• Bushings, tap changers (OLTC, DETC), radiators, conservators, and other accessories.

Module 3: Transformer Design Principles (Electrical)

• Determination of core and winding dimensions.
• Calculation of magnetizing current and core losses.
• Calculation of winding resistance and leakage reactance.
• Short-circuit impedance calculation and its significance.
• Voltage regulation and tap range determination.

Module 4: Transformer Design Principles (Thermal and Mechanical)

• Thermal design: temperature rise limits, hot spot temperature.
• Cooling system selection and sizing.
• Mechanical design: forces during short circuits, clamping, bracing.
• Noise reduction techniques.
• Vibration analysis and mitigation.

Module 5: Transformer Insulation Systems and Dielectric Strength

• Types of insulation: solid, liquid, gaseous.
• Properties of transformer oil: dielectric strength, acidity, moisture content.
• Paper and pressboard insulation: aging mechanisms.
• Insulation coordination and basic impulse level (BIL).
• Partial discharge phenomena and its impact on insulation.

Module 6: Transformer Short-Circuit Withstand Capability

• Forces generated during short circuits: radial and axial forces.
• Mechanical strength requirements of windings and clamping structures.
• Design considerations to ensure short-circuit withstand.
• Testing for short-circuit withstand (type test).
• Impact of through-faults on transformer life.

Module 7: International Standards for Transformer Testing

• Overview of relevant IEEE/ANSI and IEC standards for transformers.
• Classification of tests: routine, type, special tests.
• Importance of factory acceptance tests (FAT) and site acceptance tests (SAT).
• Quality control and assurance during manufacturing.
• Compliance and certification processes.

Module 8: Routine Tests on Power Transformers

• Measurement of winding resistance.
• Measurement of voltage ratio and phase displacement.
• Measurement of short-circuit impedance and load loss.
• Measurement of no-load loss and no-load current.
• Dielectric tests: induced overvoltage and applied voltage tests.

Module 9: Type and Special Tests on Power Transformers

• Temperature rise test for thermal performance.
• Impulse voltage tests (lightning and switching impulse).
• Short-circuit withstand test (dynamic and thermal stability).
• Noise level measurement.
• Partial discharge measurement for insulation integrity.

Module 10: Transformer Oil Analysis and Diagnostics (DGA)

• Importance of regular oil sampling and testing.
• Chemical tests: acidity, moisture content, interfacial tension, dielectric breakdown voltage.
• Dissolved Gas Analysis (DGA): principles, gas generation, and interpretation (Duval Triangle, Rogers Ratio).
• Significance of DGA in detecting incipient faults.
• Oil quality management and purification techniques.

Module 11: Electrical Diagnostic Testing On-Site

• Insulation resistance (Megger) tests.
• Dielectric dissipation factor (Tan Delta) or power factor testing.
• Capacitance measurement and its interpretation.
• Frequency Response Analysis (FRA) for mechanical integrity.
• Sweep Frequency Response Analysis (SFRA) for winding deformation.

Module 12: Partial Discharge (PD) Testing and Interpretation

• Introduction to Partial Discharge (PD) in transformers.
• PD detection methods: electrical (IEC 60270), acoustic, UHF.
• PD localization techniques.
• Interpretation of PD patterns and severity.
• Remedial actions for PD activity.

Module 13: Transformer Maintenance Strategies

• Condition-based maintenance (CBM) vs. time-based maintenance.
• Visual inspections and routine checks.
• Maintenance of tap changers (OLTC): contacts, drive mechanism, oil.
• Maintenance of cooling systems: pumps, fans, radiators.
• Oil reclamation and regeneration.

Module 14: Causes of Transformer Failures and Life Management

• Common failure modes: insulation breakdown, winding deformation, core issues.
• Factors affecting transformer aging: temperature, moisture, oxygen.
• Life expectancy assessment and remaining life estimation.
• Asset management strategies for aging transformer fleets.
• Repair vs. replace decisions.

Module 15: Advanced Monitoring and Future Trends

• Online monitoring systems for key transformer parameters.
• Fiber optic temperature sensors in windings.
• Digitalization of transformer data and analytics.
• Digital twins for real-time transformer health assessment.
• Emerging technologies: biodegradable oils, smart transformers, sensor integration.

Training Approach

This course will be delivered by our skilled trainers who have vast knowledge and experience as expert professionals in the fields. The course is taught in English and through a mix of theory, practical activities, group discussion and case studies. Course manuals and additional training materials will be provided to the participants upon completion of the training.

Tailor-Made Course

This course can also be tailor-made to meet organization requirement. For further inquiries, please contact us on: Email: info@skillsforafrica.org, training@skillsforafrica.org  Tel: +254 702 249 449

Training Venue

The training will be held at our Skills for Africa Training Institute Training Centre. We also offer training for a group at requested location all over the world. The course fee covers the course tuition, training materials, two break refreshments, and buffet lunch.

Visa application, travel expenses, airport transfers, dinners, accommodation, insurance, and other personal expenses are catered by the participant

Certification

Participants will be issued with Skills for Africa Training Institute certificate upon completion of this course.

Airport Pickup and Accommodation

Airport pickup and accommodation is arranged upon request. For booking contact our Training Coordinator through Email: info@skillsforafrica.org, training@skillsforafrica.org  Tel: +254 702 249 449

Terms of Payment: Unless otherwise agreed between the two parties’ payment of the course fee should be done 10 working days before commencement of the training.