Analysis of overload capacity of dry-type transformer

With the promotion and application of dry-type transformers, their production and manufacturing technology has also made great progress. It can be predicted that dry-type transformers will achieve further development in the following aspects in the future.

(1) High reliability: Improving product quality and reliability will be people's unremitting pursuit.

(2) Energy saving and low noise: With the introduction of new low-loss silicon steel sheets, foil winding structures, stepped core joints, environmental protection requirements, in-depth noise research, and computer optimized design and other new materials, new processes, and new technologies, future dry-type transformers will be more energy-efficient and quieter.

(3) Environmental characteristics certification: Based on the European standard HD464, research and certification are carried out on the weather resistance (C0, C1, C2), environmental resistance (E0, E1, E2) and fire resistance (F0, F1, F2) characteristics of dry-type transformers.

(4) Multifunctional combination: From a single transformer to a multifunctional combined transformer with air cooling, protective casing, temperature computer interface, zero-sequence transformer, power metering, closed busbar and side outlet.

(5) Large capacity: From dry-type transformers, which are mainly 50-2500kVA distribution transformers, to 10000-20000kVA/35kV power transformers. As urban electricity load continues to increase, urban grid regional substations are increasingly located in urban centers, residential areas, large factories and mines and other load centers. 35kV large-capacity community center power supply transformers will be widely used.

(6) Development in multiple fields: from mainly distribution transformers to power plant transformers, excitation transformers, subway traction rectifier transformers, high current electric furnace transformers, nuclear power plants, special transformers for ships and oil platforms and multi-purpose fields. Among them, the dry-type traction transformers used in urban subways and rail transit have three voltage levels of 10, 20 and 35kV, and capacities of 800, 2500 and 3300kVA. In order to reduce harmonic pollution, the 12-pulse rectification has been developed to 24-pulse rectification; the excitation transformer of the world's largest 840,000kW generator in the Three Gorges of the Yangtze River, which has attracted worldwide attention, has been successfully developed by Shunte Factory and has passed the national acceptance.