Space charge characteristics of layered and functionally graded insulator

2D spatial optimisation of functionally graded materials used as insulators for field stress control

“…However, in practical applications, the values of permittivity and conductivity can only be in the range of typical solid insulation materials. In our laboratory, we have achieved permittivity in the range of 3.5-20 and conductivity in the range of 10 −14 to 10 −12 S/m, which is realised by the addition of micro-sized fillers [14,15] into a base polymeric material. Thus, by constraining the variable property, the simulation results in this paper provide a reasonable base for real production of such insulation materials.…”

“…Impedance control is often difficult to achieve, especially since conductivity changes with temperature. Recently, the use of functionally graded materials (FGM) for electric stress control has been considered [12][13][14][15][16][17][18][19][20][21]. FGM are materials in which one or more of the material properties present a continuous spatial variation.…”

“…Previously, many researchers have attempted to optimise the permittivity distribution of the GIS spacer [12][13][14][15][16][17][18][19][20]. The key differences and advantages of our method over the previously used methods are the following:…”

“…Uniform stressing of the insulator ensures its effective utilisation. In previous works [12][13][14][15][16][17][18][19][20], the optimisation is carried out only to reduce the maximum electric field occurring in the spacer system. ii.…”

“…Thereby making this approach, a very versatile one, which can be used to optimise any material property (such as permittivity and electrical conductivity) of an insulator in accordance with its application. In previous researches [13][14][15][16][17][18], different permittivity distributions are assumed, which are applied one by one. This approach lacks in determining the optimised distribution which gives the minimum local field intensification at the triple junction.…”