Déif Analyse vun Oil Immersed Transformers: Strukturell Prinzipien, Technesch Virdeeler, a Global Applikatioun Trends (2026 Editioun)

With the acceleration of global power grid upgrades, Integratioun vun erneierbaren Energien an d'Netz, an Expansioun vun Verdeelungsnetzwierker an Entwécklungslänner, Ueleg ënnerdaach transformers remain the mainstream choice in the fields of medium and low voltage as well as medium and large capacity.


In the current market, hot topics mainly focus on three aspects:

  • Low loss and energy efficiency rating (IEC/DOE/EU Ecodesign)
  • Environmentally friendly insulating oil (mineral oil vs natural ester oil)
  • Intelligent monitoring and digital operation and maintenance (DGA online monitoring)

Oil immersed transformers are still irreplaceable in power grids, Industrie- a Biergbau Betriber, photovoltaic and energy storage systems due to their strong heat dissipation capacity, high overload capacity, laang Service Liewen, and excellent cost-effectiveness.

2.Basic structure and working principle of oil immersed transformers

2.1 Core Structure Composition

Oil immersed transformers mainly consist of the following parts:

KomponentFunktioun
KärHigh-grade silicon steel to reduce no-load loss
WindingsCopper or aluminum conductors for energy conversion
Isoléierend UelegElectrical insulation and heat dissipation
TankSealed or conservator-type oil tank
KühlsystemONAN / ONAF options
Protection DevicesBuchholz relais, Drock Relief Ventil, Temperaturindikatoren

2.2 Brief description of working principle

Transformers work through the principle of electromagnetic induction:

  • Primary winding energized → generates alternating magnetic flux
  • Magnetic flux is transmitted in the iron core → Induced voltage in the secondary winding
  • Oil serves as both an insulation and heat exchange medium

3.Types and technological differences of insulating oil (industry hotspots)

Oil TypeCharakteristikenTypical Applications
Mineral OilCost-effective, mature technologyStandard distribution networks
Natural Ester OilHigh flash point, biodegradableUrban and eco-sensitive areas
Synthetic Ester OilHigh thermal stabilityHeavy industrial applications

Trend interpretation:
In the European and North American markets, the demand for natural ester oil immersed transformers continues to grow, especially in hospitals, Subways, and commercial construction projects.

4.Matching cooling method and capacity

Cooling TypFull NameFonctiounen
ONANUeleg Natural Air NaturalSimple, low maintenance
AN OFFUeleg Natural Air ForcedSuitable for medium capacities
OFAFOil Forced Air ForcedLarge power transformers

Reasonable selection of cooling methods can significantly improve load capacity and lifespan.

5.Technical advantages of oil immersed transformers

1.Superior Hëtzt dissipation Leeschtung: high oil circulation efficiency
2.Staark Iwwerlaaschtungskapazitéit: suitable for fluctuating loads
3.Long operating life: bis zu 25-40 Joer
4.Low cost per unit capacity
5.Maintain mature system

6.Typical application scenarios

  • State Grid/Distribution Network
  • Industrial factories and mines
  • Photovoltaic booster station
  • Energy storage system matching
  • Peripheral power supply for data center

7.Future Development Direction

  • Lower no-load/load losses
  • Intelligent sensors+online monitoring
  • Comprehensive replacement of environmentally friendly insulating oil
  • Customized export standards (IEC/ANSI/GOST)

Luoyang Datang Energy Technology Co., Ltd., Ltd. ass eng High-Tech Entreprise déi R&D, Fabrikatioun a Versuergung vu Kraaftausrüstung wéi Transformatoren, nei Energiekomponenten, Verdeelung cabinets an inverters. Mat technologescher Innovatioun als Kär, mir konzentréieren op eng schafen héich-Zouverlässegkeet an héich-Performance Muecht Léisungen global Clienten ze déngen. Mat engem strenge Qualitéitskontrollsystem an international Standard Zertifizéierung, mir weider excellent Produiten eraus an erlaben Clienten sécher a stabil Muecht Systemer ze bauen.

Newsletter Updates

Gitt Är E-Mailadress hei ënnen un an abonnéiert Iech op eisen Newsletter