Study On Aging Properties Of Polymer Composite Insulators

With the vigorous development of the global energy Internet project,UHV AC/DC transmission has become the main means of energy transmission.UHV AC/DC transmission often needs to cross over some regions with harsh climate and environment,such as high altitude areas in Northwest China,which have the characteristics of perennial windiness,easy bird pecking,large temperature difference between day and night,and large differences in ultraviolet radiation distribution compared with the eastern plain areas.Traditional silicone rubber composite insulators are vulnerable to natural irresistible factors,which aggravate the aging of materials and affect their insulation performance.Therefore,in view of the aging problem of silicone rubber composite insulators in high altitude areas,this paper chooses the alicyclic epoxy resin composite insulators modified by silicone developed and provided by a research institute as the research object.Firstly,according to the ultraviolet radiation characteristics in high altitude areas,an artificial accelerated ultraviolet aging test platform was built.Ultraviolet(UVC)light was selected as the test light source to carry out 600 hours artificial ultraviolet aging test on polymer and silicone rubber samples,and its mechanical and micro-physical and chemical properties were tested.The results show that the polymer insulating material has good ultraviolet aging resistance and excellent mechanical properties.The tensile strength and hardness of the material are far superior to those of silicone rubber.It has achieved the goal of bird pecking and trampling resistance.Secondly,a cold-thermal cycle aging test platform was set up to test the 20-cycle cold-thermal cycle aging of polymer and silicone rubber samples.The test results show that the polymer materials still have good external insulation performance in the cold-hot alternating environment,and the materials can well adapt to the low temperature and high temperature alternating operation environment.Finally,the artificial pollution flashover test of polymer composite insulators is carried out to study the influencing factors of flashover voltage on the surface of materials.At the same time,the influence of arc ablation on the surface properties of materials during flashover was analyzed.The experimental results show that the polymer materials have good hydrophobic mobility;the relative humidity and salt density have a significant negative correlation with pollution flashover voltage;arc ablation has a significant impact on flashover voltage and surface conductivity of polymer materials.With the increase of arc energy,the flashover voltage of polymer materials decreases and surface conductivity increases.Figure 52,Table 26,Reference 69.