Numerical Computation Of Potential Distribution And Optimization Design Of Grading Ring Of A 1000kV UHV AC Line Insulator String

The insulator plays an important role in supporting the wire and the insulation in the 1000kV UHV AC transmission line.Its steady operation has the very vital significance to electrical power system security. This thesis has carried on the following work about numerical computation of potential distribution and optimization design of grading ring of a 1000kV UHV AC line insulator sring:Firstly the electromagnetic field numerical calculation method were Introduced, and then the electromagnetic field finite element method (FEM) was introduced with emphasis.It's proved that the power frequency electromagnetic field may compute as the quasistatic field Major technique characteristic, every component and the modelling size.of the 1000kV UHV AC transmission line were introduced.Secondly the three-dimensional model to the 1000kV UHV AC transmission line has been established with ANSOFT MAXWELL according to the actual size, and electric field distribution on insulator had been computed with the finite element method in each kind of situation, the result were contrasted and analysised The result indicates that there are mutual influence between insulator potential distribution of 1000kV UHV AC transmission line three-phase, potential distribution on insulator is very uneven It is easy to present the corona discharge phenomenon, it needs to install the equalizing ring to satisfy the project request. However grading ring with random design parameter can't play very good role, if grading ring parameter and the choice of location is improper,grading ring will present the electronics corona,this will make insulator insulating ability reduce, so the thesis introduce the neural network genetic algorithm (BP-GA)to carry on the optimization design to grading ring structure.Finally grading ring three-dimensional model were Establishment according to optimized size, and then the grading ring were installed to the insulator of the 1000kV UHV three-phase AC transmission line model to carry on the simulation computation, the grading ring structure optimization design result had been confirmed.The result indicates that potencial distribution had been distinctly improved after installing the optimized grading ring.