不同烃组成变压器油基础油的直流电场击穿性能研究

摘要

简要介绍国内外评定变压器油击穿特性的试验方法。在高压直流电场下，考察了电场均匀性与测量结果的相关性，以及不同烃组成变压器油基础油的击穿特性；在极不均匀直流电场下，考察不同类型芳烃含量与油击穿特性的相关性。研究结果表明：在极不均匀直流电场下，变压器油的击穿电压与其烃组成有极大的相关性，变压器油芳烃含量越高，正负极性击穿电压越低，在相同电极间隙下负极性击穿电压高于正极性击穿电压，电极间隙越大，这种差异越大；单环芳烃对变压器油直流击穿电压没有负面影响，双环及多环芳烃对变压器油直流击穿电压有明显的负面影响。%The breakdown characteristics of transformer oils in DC electric field are one of the key factors to decide the safe operation of equipment. In this paper,the breakdown voltages test methods of transformer oils at home and abroad are briefly introduced. In HVDC electric field,the relevance of electric field uniformity and breakdown voltage,and the performance of electric breakdown of trans-former oils with different hydrocarbon compositions as well as the relations between types of aromatics and their content and breakdown characteristics in uneven DC field are investigated. The results show that in uneven electric field,breakdown voltage of transformer oils has a great correlation with their hydrocarbon composition. The higher the aromatic hydrocarbon content in transformer oil,the lower the breakdown voltages in positive and negative polarity. Under the same electrode gap,the negative polarity breakdown voltage is higher than the positive polarity breakdown voltage of transformer oils.The breakdown voltage of transformer oils increases in direct ratio with the increase of electrode gap.The content of polycyclic aromatic hydrocarbons is the key factor affecting DC breakdown voltage of transformer oil;while monocyclic aromatics do not negatively affect the DC breakdown voltage.