2.4. Meshing
As part of the FEM procedure the entire domain is divided into non-overlapping triangular mesh elements. The size of the mesh elements can be varied manually on any chosen part of the insulator’s surface to enhance the accuracy of the simulation. Fewer mesh elements may reduce the accuracy of the simulation results, while too many elements can lead to high memory consumption and longer processing time. Determining an optimised mesh will facilitate a faster computation time without reducing the accuracy of the result. Mesh discretisation of the insulator domain problem can be seen in Figure 6.6.The insulator model was simulated in the FEM analysis using an AC/DC module (Static Electric mode), which assumes that currents and electromagnetic fields vary slowly. This mode is valid for many HV applications including outdoor insulators that operate at power frequencies of 50-60 Hz[6.4].