Efficiency Cornerstone: The Key Role and Green Transformation of Oil-Immersed Transformers in Modern Power Grids

In the process of building new power systems, oil-immersed transformers, as core equipment for power conversion, are facing dual challenges of improving efficiency and green transformation. This article delves into the energy efficiency optimization technologies, full lifecycle management, and innovative applications of oil-immersed transformers in smart grids.

I. Innovations in Energy Efficiency Improvement Technologies

The new generation of oil-immersed transformers achieves breakthroughs in energy efficiency through several technological innovations:

1. Application of Low-Loss Silicon Steel Sheets
   The use of high-permeability, low-loss grain-oriented silicon steel sheets reduces no-load losses by more than 25% compared to traditional materials. One manufacturer successfully controlled the no-load loss of a 31,500 kVA transformer within 28 kW by using high-performance silicon steel sheets with a thickness of 0.23 mm.
2. 3D Wound Core Structure
   Three-dimensional wound core technology makes the magnetic flux distribution more uniform, reducing no-load current by 40% and noise levels by 15 dB. This is particularly suitable for noise-sensitive scenarios such as urban central substations.
3. Intelligent Temperature Control System
   Equipped with variable-frequency cooling devices, it automatically adjusts fan speed based on load rate. Experimental data show that the intelligent temperature control system can reduce operating energy consumption by 35% at 60% load.

II. Full Lifecycle Management Strategies

Modern oil-immersed transformers adopt a full lifecycle management model:

1. Condition-Based Maintenance System
   Real-time collection of 16 parameters, including dissolved gases in oil and winding temperature, through online monitoring devices. Big data analysis achieves a fault warning accuracy rate of over 90%.
2. Life Extension Technical Transformations
   For transformers operating for over 20 years, insulation system reinforcement upgrades are carried out, including replacement of insulating pressboards and sealing system upgrades, extending equipment life by more than 15 years.
3. Green Decommissioning Solutions
   Establish a comprehensive recycling system with a transformer oil regeneration rate of 95% and copper material recovery rate of 99%, truly achieving a circular economy.

III. Innovative Applications in Smart Grids

In the construction of new power systems, oil-immersed transformers demonstrate new application value:

1. New Energy Integration Hub
   As step-up transformers for wind farms and photovoltaic power stations, they possess special capabilities to withstand grid harmonic impacts and frequent load changes. In an offshore wind power project, specially designed oil-immersed transformers successfully handled short-term overloads of 2.5 times the rated capacity.
2. Intelligent Voltage Regulation Node
   Intelligent transformers equipped with on-load tap-changers can achieve automatic voltage regulation, increasing the qualified rate of distribution voltage to 99.99%.
3. Digital Twin Applications
   Establishing digital twin models of transformers enables state assessment and fault prediction through real-time data mapping, reducing maintenance costs by 30%.

IV. Path to Environmental Transformation

Faced with increasing environmental requirements, the oil-immersed transformer industry is actively promoting green transformation:

1. Application of Eco-Friendly Oils
   The use of bio-based ester insulating oils increases the biodegradability of transformer oil from 35% to 98%, reducing toxicity to 1% of that of mineral oil.
2. Noise Reduction Technology Innovations
   The combination of low-noise cores, elastic fixation structures, and soundproof enclosures controls the noise of 550 kV transformers below 65 dB.
3. Fully Sealed Structure
   Stainless steel sealed tanks combined with innovative rubber materials ensure 30 years of maintenance-free operation, eliminating oil leakage.

Conclusion

With the deepening of the “dual-carbon” strategy, oil-immersed transformers are rapidly developing toward high efficiency, intelligence, and environmental friendliness. Through breakthroughs in new material applications, intelligent monitoring, and green manufacturing, the new generation of oil-immersed transformers not only the high reliability of traditional equipment but also achieves significant progress in energy efficiency improvement and environmental protection. In the future, with the deep application of digital twin and artificial intelligence technologies, oil-immersed transformers will undoubtedly play an even more important role in building new power systems.