Investigation On Nanocomposite VPI Resins For Main Insulation Of High-voltage Electric Machines

As people living in the demand for electricity is becoming more and more big,makes the generator capacity increase,the size of the motor is increased with the increase of capacity of change,in the production of motor manufacturing cost also soared.Thinning the thickness of the insulation to reduce the size of the high voltage motor,improve the heat dissipation,lower the manufacturing cost is of great significance.For thinning the main insulation thickness,we must improve the breakdown performance of insulation materials and electrical life.Existing research shows that the polymer nanocomposites with excellent mechanical and thermal properties and breakdown performance,is the main one of the important research direction in the field of insulating materials.Based on the research for many years,on the basis of research on polymer nano composite resin,the epoxy resin vacuum pressure impregnation（VPI）resin for the study of nanometer modified.First of all,in order to overcome the anhydride type and boron amine type on the market the shortcoming of VPI epoxy resin,developed a new VPI resin is suitable for the introduction of nano powder;Then the resin as matrix resin,nano Al₂O₃ powder（C805）as the filler,this paper discusses the dispersion method of nanometer powder decentralized state,the viscosity of composite resin,the curing properties,such as breakdown strength and electric life;After determine the dispersion method,and further discusses the types of powder（Al₂O₃,SiO₂,TiO₂）and the influence of dosage of nanometer Al₂O₃.The results showed that the phenolic compounds with A mixture of aluminum acetylacetonate as curing agent,and in high purity bisphenol A type epoxy resin is introduced into the right amount of methyl phenyl glycidyl ether（691）,can be made suitable for the introduction of nano powder resin VPI.Using contains phi 0.2 mm zirconia beads scattered sand mill C805,can basically eliminate nano powder reunion phenomenon.Use the same dispersion method of nanometer SiO₂ and dispersion of nanometer TiO₂ results vary,impregnating resin is of different powder agglomeration phenomenon,lead to material viscosity increases sharply,curing dielectric performance degradation.With the increase of dosage of C805,impregnating resin viscosity increases,adding quantity is close to lose more than 8%when impregnated resin fluidity;With the increase of dosage of C805,curing of the electric life longer,when C805 content is 5.4%,compared to curing the electrical life of pure resin increased 1.6 times.