Accelerating the frequency-domain response calculation of complex grounding system using wavelet based MBPE technique

The transient response of grounding systems is essential for their designs and related electromagnetic compatibility problems in power systems. Although the method of moments (MoM) is a popular way to analyze the responses of grounding systems, it is prohibitively slow. In this paper, the model-based parameter estimation (MBPE) technique and wavelet matrix transform (WMT) are combined and applied to the method of moments (MOM). It is expanded on two-steps technique to accelerate solution of electric field integral equations (EFIE). In a first step, the WMT is used to get a sparse matrix equation in wavelet-domain. Then in a second step, the adaptive model-based parameter estimation is used to reduce the number of frequency-domain calculation points required for the evaluation of space-time current distribution along a grounding grid. The accuracy of the proposed model is confirmed by comparing the simulation results of several case studies with those obtained using the direct MoM method combined with inverse fast Fourier transform (IFFT). It is shown that considerable computation efficiency is achieved in terms of CPU time without losing accuracy.