Study On Structure Optimization And Electrical Performance Of Capacitive ZnO/PLA Insulators

With the continuous development of long-distance and large-capacity transmission systems,UHV electrical equipment is playing an increasingly important role.Meanwhile,the insulation characteristics of electrical equipment are increasingly required,an d the insulation performance of existing equipment needs to be further improved.Secondly,with the emergence of new manufacturing means and new materials,additive manufacturing technology makes it possible to manufacture many complex insulators.The use of new manufacturing process to prepare insulators with complex structure and better anti-flashover ability has become a research focus in this field.In this paper,aiming at the structural optimization problem of a new capacitive ZnO/PLA insulator,the electric field distribution along the surface is regulated from three aspects,namely the geometric shape of the insulator,the radial thickness distribution of the material and the modification of the filler.The finite element software is used to simulate the electric field along the surface of the insulator.The results show that:Compared with the non-optimized insulator,the maximum electric field along the surface of the insulator simply optimized by geometric shape decreases by 74.65%.On this basis,combined with the radial thickness distribution of the optimized material,the maximum electric field along the insulator’s surface is reduced by 2.43%.Taking geometric shape optimization,radial thickness distribution optimization and filler modification into consideration,the surface maximum electric field of the prepared insulator is reduced by 77.79%compared with that of the unoptimized insulator,and the surface electric field distribution is more gentle,which plays a role in homogenizing the surface electric field.In order to optimize the electrical resistance of insulators,composite epoxy coating materials were prepared by using coupling agent after surface modification of nano-zno powder.Based on additive manufacturing process,several capacitive ZnO/PLA insulators with different geometric shapes and radial thickness distribution of materials were prepared by considering simulation results,and their electrical properties were tested.The test results show that the capacitive structure constructed by optimizing the geometry and radial thickness distribution of the insulator can effectively reduce the dielectric loss of the insulator and increase the flashover voltage of the insulator.Compared with ordinary insulators,when ZnO powder is treated with coupling agent,the dielectric loss of insulators with optimal geometry and thickness distribution is reduced by 24.81%,the volume resistivity is increased by 54.66%,and the flashover voltage is increased by 46.75%.The research in this paper shows that by changing the geometric shape parameters of insulators,radial thickness distribution parameters and composite epoxy coating material parameters,combining the structural optimization method in insulation design with the material modification method,the electric field distribution along the surface of insulators can be effectively homogenized and its electric resistance can be improved.The capacitive structure not only provides the possibility for further improving the flashover problem along the surface of insulators,but also provides the possibility for improving the flashover along the surface of insulators.It also provides a new idea for the development of new insulator with complex structure.