Determination Of Aging Status Of Oil-immersed Insulation Paper And Nanomodification

With the rapid development of electric power system,people have put forward higher demands on the safety and stability of electric power system and the capacity of electric power system.The economic loss caused by the sudden failure of power transformer is incalculable,it is very important to ensure the normal operation,timely maintenance,timely detection of problems and prediction of aging state and operating life of large power transformer.In addition,because the cost of power transformer is very expensive and high,in addition to the large volume,weight of hundreds of tons,transport,installation is more difficult,so to improve the operating life of transformers has become a hot topic of scholars at home and abroad.Of all the system components of power transformers,insulation is the most vulnerable and prone to failure.To find a more accurate and easy way to judge the aging state of transformer insulation system is a hot topic that scholars have been discussing.According to the water balance relation curve in oil paper,the specific relation formula of water content in oil paper is proposed.Based on the zero-order kinetic model and chemical reaction Kinetics,the relationship between water content and the degree of polymerization in paper was proposed.It is not practical to measure the moisture content in transformer insulation paper,but it is easy to measure the moisture content in oil,and it will not cause any damage to transformer insulation system.Besides accurately and simply judging the aging state of the insulation system,how to improve the insulation performance of the insulation system and reduce the failure rate is also an important topic in modern society.With regard to insulation paper modification,this paper mainly adds nano-silicon dioxide to the insulator paper,weighing the quality of each piece of insulator paper under the condition of absolute dry,adding different nano-silicon dioxide,making the quality fraction of the added silicon dioxide is 0 %,2 % and 4 % respectively,then pulp,paper,drying,and making circular insulator paper.Three groups of insulating paper with different concentration of Silicon dioxide were put into thermal-vibration box,aging time was 48 h,96h,144 h,192h,240 h respectively.The results showed that the insulation property of the aged insulating paper was better,the tensile strength and electrical property were greatly improved.