Grounding and Earthing

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SCIENCE FOR ENGINEERING

THE STATE OF THE ART OF THE ELECTROMAGNETIC SIMULATION FOR POWER SYSTEMS, GROUNDING, INTERFERENCE AND LIGHTNING

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MODULES FOR GROUNDING AND EARTHING SYSTEM ANALYSIS 

Searching for a powerful and reliable grounding and earthing system analysis software for your electrical power systems?

Look no further than XGSLab. Our software, powered by advanced algorithms and user-friendly interfaces, provides accurate and detailed simulations of grounding and earthing systems, allowing engineers and researchers to evaluate and design these systems with precision and efficiency. Trust XGSLab grounding and earthing system analysis software to optimize the safety and performance of your electrical power systems.

Get the best results in your grounding and earthing system analysis by choosing XGSLab software, the industry leader in this field.

XGS includes the following modules specifically developed for grounding and earthing system analysis:

  • GSA: this module can be used for analysis of underground systems at low frequency and is commonly used for small and medium size plants like substations or tower footing
  • GSA_FD: this module can be used for advanced analysis of underground systems in the frequency domain from DC to about 100 MHz and is commonly used for medium and large systems size like substations, photovoltaic plants or wind plants, for cathodic protection and anode bed analysis or for calculations at high frequency
  • NETS: this module can be used for the evaluation of fault current distribution and and is commonly used for the split factor calculation in general conditions
Modules GSA and GSA_FD include the tools SRA and SA for soil resistivity analysis, soil resistivity seasonal analysis and multilayer soil modelling starting from soil resistivity measurements, soil parameters and local climatic conditions.

  

  • GSA  (Grounding System Analysis)
  • GSA_FD (Grounding System Analysis in the Frequency Domain)
  • NETS (Network Solver)

BENCHMARKS  

Several software providers offer earthing/grounding system analysis products, but few speak of calculation accuracy. Accuracy can be a significant challenge for simple products, and XGSLab is trusted by users to provide accurate results for systems of any size and complexity.

The IEEE Std 80-2013 provides some benchmarks, but these only present simpler equipotential systems, and thus present a bare minimum of capabilities for software. For small systems, it is acceptable to ignore voltage drop and assume an equipotential grid. For large or complex systems, the voltage drop is not negligible and more robust calculation methods are required to compare simulations with measured real-world values. The reality is that many substations and generation facilities, such as for large photovoltaic or wind power plants, require more robust tools that consider voltage drop as it may be significant. Unfortunately, in these cases there are no benchmark.

The following figure shows a comparison between some commercial tools.

grounding_comparison.png

XGSLabTM GSA_FD and CDEGS® HIFREQ High Precision compare well in a case study, available online, consisting of a grid 500x500 m with meshes 25x25 m, depth 0.5 m, wires copper AWG 4/0 with resistivity 1.8*10^-8 Ωm, current 1000 A 60 Hz injected in a grid corner. The soil model has been assumed as uniform, with relative permittivity 1 and resistivity in the range 1 – 10000 Ωm.

Differences between results provided by XGSLabTM GSA_FD and CDEGS® HIFREQ High Precision are negligible (results are overlapped). Taking into account the two software are both full-wave and based on different numerical methods (PEEC and MoM respectively), we are confident that this simulation benchmark could be added in standards such as IEEE Std 80 for the industries benefit.

Any approximation leads to a limitation of the accuracy.

CDEGS® HIFREQ Default Precision uses an approximate calculation of the Sommerfeld integrals, much faster but also less precise.

CDEGS® MALZ does not consider mutual impedances, calculation is very fast but accuracy in the common resistivity range is unacceptable.

ELEK® SafeGrid behavior seems similar to CDEGS® MALZ.

Equipotential assumption is clearly unacceptable for most of the resistivity range.