An Adaptive Chebyshev Approach for Fast Computation of Grounding System Admittance Matrix

Hybrid continuous circuit‐trapezoidal integration method analysis of multi‐cross structure of grounding system

“…The grounding system's behaviour at power frequency (50 or 60 Hz) is well defined with a constant lumped resistance [7]. The analysis of grounding grids during a high-frequency phenomenon could be investigated using experimental and semi-theoretical methods [8][9][10][11][12][13] and numerical approaches [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Three basic simulation approaches can be classified for grounding transient analysis: transmission line model [14][15][16], electromagnetic field model [17][18][19][20][21][22][23][24][25][26][27][28], and circuit model [29][30][31][32][33].…”

“…The electromagnetic field model is a rigorous approach based on electromagnetic field theory for computing the quantities that characterise grounding system behaviour. The numerical electromagnetic method in literature is based on method of moments (MOM) [19][20][21][22], the finite-element method (FEM), finite-difference time-domain (FDTD) [27], hybrid electromagnetic model (HEM) [28]. Although these methods give more adequate results, the simulation process by these approaches often needs enormous computer memory and computation time.…”

“…The proposed method in this paper is valid and accurate for all the frequency range of lightning transient. To decrease the computation time, due to the time-consuming nature of the solution in the frequency domain in MoM, an adaptive Chebyshev method is utilised to reduce the number of frequency points [20]. It is shown that the selected sampling frequencies are sufficient to generate the exact response of the grounding system over the working frequency interval.…”