A Optimization Of Main Insulation GAP Of 220kV Power Transformer

Supported by the relevant research,and combining with the research on insulation structure of power transformer,the aim of this paper is to conclude the accomplishment realized by author.At the same time,this method has been used in practical products.According to statistics,transformer's malfunction during operation is always led by insulation failure.It has been proved that insulation design plays a crucial role in transformer design subject,especially for large power transformer.Meanwhile,insulation gap is important not only to rationality of transformer,but also to the cost of transformer.Transformer operating stably depend on the rationality of its insulation structure design.It is essential to determine the regions with highest electric field strength,and take some measures to cope with these regions to make the insulation more reliable.In this paper,we mainly studied the electric field distribution for 220 kV power transformer.There is no doubt that the insulation gap should be lager in the regions where the difference of potential is large between HV coil and LV coil.With this method,HSSSM software is used to calculate the electric field distribution.And a reasonable structure was found and meet all the insulation requests.Finally,this new method was used in one product,of which all the tests have been pasted successfully.This new method is reliable.