1. Overview

Power transformers are static electrical devices that transfer energy between circuits through electromagnetic induction. They enable voltage conversion (step-up/step-down) while maintaining galvanic isolation. These components are fundamental in power distribution systems, renewable energy integration, and industrial equipment, ensuring efficient energy transmission and voltage level adaptation.

2. Main Types and Functional Classification

3. Structure and Components

Typical construction includes:

• Core: Grain-oriented silicon steel laminations for magnetic flux path
• Windings: Primary/secondary copper/aluminum coils with insulation layers
• Insulation: Mineral oil, synthetic esters, or solid materials (e.g., epoxy)
• Cooling System: Radiator tanks, fans, or forced-oil circulation
• Tap Changer: On-load/off-load voltage regulation mechanism
• Protection: Buchholz relay, pressure relief valves, temperature sensors

4. Key Technical Parameters

5. Application Areas

Major sectors include:

• Electricity distribution networks (urban/rural)
• Renewable energy systems (wind/solar grid-tied inverters)
• Industrial machinery (CNC, smelters, compressors)
• Railway traction systems (15kV-25kV conversion)
• Data centers (HVDC conversion systems)

6. Leading Manufacturers and Products

7. Selection Guidelines

Key considerations:

• Voltage levels (primary/secondary requirements)
• Load profile (continuous vs. intermittent duty)
• Cooling requirements (ONAN/ONAF/OFAF modes)
• Environmental conditions (temperature, altitude, seismic zones)
• Protection features (IP rating, fire resistance)
• Smart grid compatibility (IoT sensor integration)

Case Study: Wind farm grid connection selected 33/132kV ONAF-cooled transformer with 12% impedance to meet fault ride-through requirements.

8. Industry Trends

Current development directions:

• Smart transformers with real-time monitoring (IEEE C57.163 compliant)
• Amorphous metal core adoption (50% core loss reduction)
• Hydrogen-cooled systems for offshore applications
• Modular solid-state transformer (SST) prototypes (DOE GRID DATA initiative)
• Increased demand for 132kV+ mobile transformers in disaster recovery

Market forecasts indicate 6.2% CAGR through 2030, driven by grid modernization and EV charging infrastructure expansion.