Basin-type Insulator Optimization Based On Dielectric Functional Gradient Material

With the increase of the power grid voltage level and the continuous increase of system capacity,GIS equipment tends to be miniaturized and the amount of equipment failure increases rapidly.Basin-type insulators play the role of supporting conductors,isolating gas chambers and electrical insulation in GIS and are the weakest link in GIS.The emergence of dielectric functional gradient materials(8-FGM)provides new ideas for optimization of electric field distribution of basin-type insulators.In order to reduce the maximum field strength and improve the distribution uniformity of the electric field along the spacer surface,it is of great significance to optimize the dielectric functional gradient basin-type insulator.In this paper,the dielectric functional gradient material is simulated by the layered method,and a conceptual simulation model of the s-FGM basin-type insulators is established by using half of the axial section in an axisymmetric manner.For double-layer s-FGM basin-type insulators,using ANSYS parameterized design language(APDL)to compile finite element analysis files,achieving variable-parameter finite element calculations,the influence of the permittivity at the high voltage end of the insulator and the size of the optimized region on the maxirmum field strength along the surface are studied.Based on the above studies,the dielectric constants at the high and low voltage sides of the basin-type insulators were taken as design variables,and the dielectric constant difference between neighboring layered insulators was used as the state variable,zero-order algorithm and scanning method are used to optimize the radial permittivity distribution of ε-FGM basin-type insulators.By changing the number of iterations and reasonably limiting the range of design variables,the simulation results tend to be optimal.The software implementation methods of MATLAB and ANSYS combined simulation are elaborated in detail.The interface programs of MATLAB and ANSYS software are written,through the interface program,ANSYS can be called as a subroutine in MATLAB.the external text is read and written by MATLAB and ANSYS to achieve the transfer of parameters,thus combining the weighted linear descending particle swarm optimization algorithm with finite element analysis.In order to improve the optimization effect,the dielectric constant ratio of adjacent layered insulators at the high and low voltage sides is the design variable,and the s-FGM basin-type insulator are optimized.Finally,the advantages and disadvantages of the zero-order algorithm and the improved particle swarm optimization algorithm are analyzed in terms of optimization results and simulation efficiency.In order to obtain the global optimal solution of the radial dielectric constant distribution and improve the applicability of the optimization algorithm,this paper proposes a global optimization algorithm for radial permittivity distribution of insulators based on the surface field strength feedback.Through the joint simulation of MATLAB and ANSYS,the effects of the step size and the number of stratifications on the maximum field strength and the radial permittivity distribution are studied.Finally,the proposed optimization algorithm was applied to the optimization of the permittivity distribution in the two-dimensional space of the insulator and the optimization of the shielded polar basin-type insulator.The above algorithm has many advantages such as less parameters,higher optimization efficiency,and faster convergence speed.The optimization effects of the proposed algorithm on the surface maximum field strength and surface electric field utilization efficiency are better than the zero-order algorithm and the improved particle swarm algorithm.The research results of this paper can provide reference for the optimization design of insulation materials in power system.