The development direction of dry-type transformers in recent years

The annual output of dry-type Transformer has reached 10000mva, which has become one of the largest countries in the world. With the popularization and application of SC (b) 9 series with low noise (distribution transformer noise below 2500kVA has been controlled within 50dB) and energy saving (no-load loss reduced to 25%), the performance index and manufacturing technology of dry-type transformer in China have reached the international advanced level. With the popularization and application of dry-type transformer, its production technology has also made considerable progress. It can be predicted that the future dry-type transformer will be further developed in the following aspects.

(1) Energy saving and low noise: with the new low-consumption silicon steel sheet, foil winding structure, step iron core joint, environmental maintenance requirements, in-depth discussion on noise, and introduction of new materials, new processes and new technologies such as computer optimization design, the future dry-type transformer will be more energy-saving and quieter.

(2) High reliability: it will be people's unremitting pursuit to improve product quality and reliability.

(3) Certification of environmental protection characteristics: Based on the European standard HD464, the discussion and certification of dry-type transformer's weather resistance (C0, C1, C2), environmental resistance (E0, E1, E2) and fire resistance (F0, F1, F2) characteristics is carried out.

(4) Large capacity: from 50-2500kva distribution transformer based dry-type transformer to 10000-20000kva / 35kV Power transformer, with the continuous increase of urban power load, the substation in urban area is more and more deeply into the load center of urban central area, residential area, large-scale factories and mines, and 35kV large-capacity residential center power supply transformer will be widely used.

(5) Multi functional combination: from single transformer to multi-functional combined transformer with air cooling, maintenance shell, temperature computer interface, zero sequence transformer, power metering, enclosed bus and side outlet.

(6) Multi scope development: mainly from distribution transformer to power station auxiliary transformer, excitation transformer, metro traction rectifier transformer, high current furnace transformer, nuclear power station, marine and oil production platform and other special transformers and multi-purpose category. Among them, the dry-type traction transformer used in urban subway and rail transit has three levels of voltage of 10, 20 and 35 kV, and the capacity of 800, 2500 and 3300kva. In order to reduce harmonic pollution, the 12 pulse rectifier has been developed to 24 pulse rectifier; the excitation transformer of 840000 kW generator in the world's largest Three Gorges project has been successfully developed by Shunde factory and has passed the national acceptance. In the 21st century, it is predicted that the dry-type transformer and its insulation performance will be superior.