FEM Calculation Of High Voltage Insulator Electric Field And Optimization Of Grading Ring

Modern insulator is made of ceramic, glass or silicone rubber. The insulators areconnected with high voltage line and metal tower. When the power system is normal, thepotential distribution on the insulator is highly homogeneous and uniform. So we placedgrading rings on both ends of the insulator to prevent the occurrence of corona phenomenon.However, the grading ring’s parameters are not optional, because surface potential high willeasy to cause corona or electrical breakdown phenomenon. Therefore we need optimize thegrading ring. The cost of the experimental methods is very high difficult, so it is necessaryto use software simulation, in order to guide practical engineering application. This papermainly did the following work.Firstly, the paper introduced the physical model, and the specific analysis for this realmodel.It explained in the model what is simplified, the open domain field and how to dealwith the finite element software ANSYS to realize modeling, assign attributes, andboundary condition, solving and post-processing. It calculated the insulator potentialdistribution under such circumstances to get the results analyzed. The highly uniform ofinsulator potential distribution, the quickly dropped end potential and the electric fieldconcentration lead to corona phenomenon even breakdown. It needs to be placed suitablesize grading ring in the insulator ends that can meet the practical engineering requirements.The following several factors influences the insulator’s potential distribution: the length ofthe insulator, the radius of the grading ring and the pipe radius of the ring, grading ringinstallation height (raise distance) and the terminal is grounded. This paper respectivelyanalyzed the above few parameters on the influence of potential. It is a certain guidingsignificance for analysis of the grading ring reference size parameter range to the actualengineering. Then we calculated the results based on the optimized size and verify theresult of optimization design. Finally, the paper analyzed the insulator of transient electricfield calculation and calculated the resistance value and equivalent capacitance value. Byusing ANSYS software to insulator transient electric field was simulated.