Application of the multiple grid method in electric field calculation of high-voltage interrupter

In view of the disadvantages of conventional finite difference method (FDM) in handling the complicated boundary of electric fields and in eliminating the smooth error of iteration, in this paper, the differential equation is employed to generate regular calculation grids from the original region to be calculated. So, the approximation of the boundary condition in calculation is avoided. The multiple grid method (MGM) is adopted in the electric field calculation on the transformed region for eliminating the smooth error, expediting the convergence, and increasing the calculation precision. The convergence property of the MGM has been verified by both the theoretical analysis and the numerical solution. The merits of the method provided in this paper have been verified by comparing with FDM, finite-element method (FEM), and boundary-element method (BEM).