Calculation And Analysis Of Strength To Anti-short-circuit For Transformer Based On ELDINST Software

At first,this paper briefly introduces the calculation principle and calculation method of ELDINST software,including operation interface of the software,the basic process of software calculation,the establishment of the software model,and the result of the final output of the software.In addition,it also introduces the basic functions and features of the software.Then focuses on the short-circuit current calculation and short circuit force analysis of the transformer windings,and all short-circuit conditions of the power system are analyzed,including a three-phase,two-phase or single-phase short-circuit conditions.In addition,the transient and the steady-state short-circuit current calculations are are analyzed,and then analyze the short-circuit withstand capability of transformer windings under different faults,including radial force calculation and the axial force calculation.Finally,the thermal stability of the transformer is described.Then through fault transformer of 220 kV which occurring single-phase to ground an example,according to the basic situation of the transformer fault,as well as a variety of testing and analysis before the disintegration of the fault transformer.Then the short-circuit withstand capability of transformer windings under different conditions is calculated and analyzed in detail base on ELDINST software.In particular,short-circuit current and short-circuit strength of a transformer occurring single-phase to ground are calculated and analyzed,the maximum force value and the safety factor are calculated in the different parts of the windings of the transformer.Through the comparison of the real checking results of the fault transformer and the calculation results of the ELDINST software,it shows that the checking results are basically consistent with the results of the calculation,this also shows that the accuracy of ELDINST software for the calculation of the short-circuit strength of the transformer are confirmed,while guiding significance for raising ability of anti-short circuit of the transformer designing.Finally,this paper discusses and summarizes the measures to raise ability of anti-short circuit of the transformer,according to the calculation results of the short-circuit strength of the transformer,the rectification measures are put forward.through these measures,the short-circuit strength of transformer windings before and after the rectification is compared and analyzed by ELDINST software.The resultsshow that the software calculation and the actual rectification of the situation is consistent,and the short-circuit strength can be greatly improved.The accuracy of the software calculation and the guiding significance for the design of the structure of the transformer are fully confirmed.At the same time,it has important reference value for the development of the transformer and reliable operation of the transformer.