大型电力变压器短路事故统计与分析（Short circuit accident statistics and analysis of large power transformer）.docVIP

大型电力变压器短路事故统计与分析（Short circuit accident statistics and analysis of large power transformer） Short circuit accident statistics and analysis of large power transformer Wang mengyunlings first words Power transformer in the power system operation, short circuit is that people try to avoid and cannot be absolutely avoided, especially in the export (head) short circuit, huge mechanical force produced by over current, great harm to the power transformer. Therefore, the national standard GB1094 and international standard IEC76 have made corresponding provisions on the ability of the power transformer to withstand the short circuit, and the power transformer should be able to withstand various short circuit accidents in the operation. Nearly five years, however, to the national more than 110 kv voltage class power transformer accident statistical analysis shows that the accident caused by short circuit strength enough has become the leading cause of electric power transformer fault, seriously affected the safe and reliable operation of the power transformer. In this paper, the damage of power transformer accident due to short-circuit the external situation of statistical analysis, put forward the measures to reduce this kind of accident, an attempt to promote manufacturers to improve and perfect the power transformer products, at the same time operating departments to further improve the level of operation and management. Short circuit accident of large power transformer According to incomplete statistics from 1991 to 1995, there were 317 accidents in the total capacity of 110kV and above voltage grade transformers in China, and the total capacity of accidents was 25348.6 MVA. The average accident rate was 0.83%, with an average accident rate of 1.10%. In these accidents, there were 93 cases of power transformer damage caused by external short circuit, and the capacity was 6677.6 MVA, accounting for 29.3% of the total accident stage in the same period, accounting for 26.3%