Grounding System Analysis in the Time Domain
XGSA_TD is a multipurpose Engineering Software for the analysis of conductors network in the time domain taking into account transients with maximum bandwidth up to about 100 MHz including Soil Resistivity Analysis and Fourier Analysis.
XGSA_TD extended the application field of XGSA_FD to the time domain.
XGSA_TD is a powerful module which extends the XGSA_FD application field to the time domain.
In this regard, XGSA_FD uses the so called “frequency domain approach”. This approach is rigorous and allows considering the frequency dependence of soil parameters.
As known, a transient can be considered as the superposition of many single frequency waveform calculated with the forward Fast Fourier Transforms (FFT).
Using the frequency domain PEEC model implemented in XGSA_FD it is then possible calculate a response for each of these single frequency waveform.
The resulting time domain response can be obtained by applying the Inverse Fast Fourier Transform to all these responses calculated in the frequency domain.
The calculation sequence implemented in XGSA_TD is also called FFT – PEEC – IFFT.
XGSA_TD has been tested for the simulation of transients with a maximum frequency spectrum up to 100 MHz and then can be used for switching transients, lightning and also in fault transients in GIS.
XGSA_TD can consider transients with known equations like Double Exponential, Pulse or Heidler (transients used in EMC studies).
XGSA_TD can also consider transients with arbitrary equations or recorded and then known as a discrete number of samples (transients used in lightning and HV studies).
XGSA_TD includes an option to export frequency dependent self and mutual impedances to EMTP® or ATP® in order to simulate with a rigorous model the dynamic behaviour of large grounding systems during electromagnetic transients.
Tags: Grounding and Earthing Analysis, Grounding Systems, Earth Resistance, Touch and step voltages, Soil modeling, Lightning protection, Soil ionization, impulse impedance