The Development Of Large Air-cooled Sfsz-180000/220 Power Transformers

With the rapid development of national economy in our country, electric power industry develops rapidly. Electro-quantity of townsman in economy developed areas of our country has reached or approached the level of developed country. Transformers of 220kV grade which have been used in central zone of city and industry economy region, have become power-supply centrums. As the one of key equipments in transformer substation, transformer is required to have higher reliability, technical economy guide line and environment protection demand. The large analysis software can be used to analyze leakage magnetic field, electric field, winding wave process and dispersing thermal capability of the transformer. The large electric power transformer of 220kV grade with natural oil circulation can be researched and designed by using analysis software that will have important benefit in technology, economy and society.The tradition design of the large electric power transformer of 220kV grade is depended on experience because of condition restriction. The whole reliability of the insulation configuration needs to be more increased and the stray loss in the metal pieces of the tank can't be controlled effectively because the analysis of the leakage magnetic field and electric field isn't particular. The type of forced oil air cooling is used in huge content electric power transformer of 220kV to disperse thermal completely. But this cooling type has several disadvantages such as adjuncts have big noise and velocity of flow is high that will bring electrification and have low reliability.By using the analysis software, the paper researches and designs the large air blast cooling electric power transformer which type is SFSZ-180000/220, in order to optimize configuration, reduce losses and noise, increase dependability and satisfy the requirement of protecting environment and economizing energy sources. Some primary works are done in the paper. The main-vertical insulated configuration with scientific and reasonable terminal outlet is confirmed by the analysis of the electric field and winding wave process, in order to increase the reliability. The magnetic shield configuration is confirmed by the analysis of the leakage magnetic field, in order to reduce the eddy current losses produced in the tank by the leakage magnetic and remove the part super-heat phenomena. The reasonable system is chosen by the analysis of the dispersing thermal system in order to realize natural oil circulation air cooling, reduce the noise produced by adjuncts, remove the phenomena of electrification with oil flow and increase the running reliability.