An earthing grid is used as an electrical connection that is located to the earth at zero potential in which when a fault condition occurs then the flow of current dissipates into the ground through the low impedance path.
Importance of Earthing Grid
Potential differences in touch voltage and step voltage and their combination which is hazardous for the human body due to these people can carry electric current easily thus lead them towards life-threatening problems. These dangerous issues can be easily eliminated by equipping an earthing grid which should be designed properly in order to minimize the harmful effect.
Applications
1. Substations.
2. Transformers.
3. IT system.
4. Pipelines.
5. High-voltage power lines.
6. Tunnels.
7. Metros.
A failed earthing system can cause disastrous conditions for the equipment along with the operator of the equipment. Hence, properly designed of earthing system is must to have for better electrical safety.
In the designing of earthing grid, Step potential, touch potential & ground potential rise plays an important role in achieving the complete electrical safety in case of fault occurrence in the system. In order to achieve the desired values in earthing grid, soil resistivity takes a necessary part in the designing. As we all know, soil is variant in nature at different locations thus doing soil resistivity analysis is very much important now.
The major challenges we generally face is High Soil Resistivity Values, Limitation of Availability of area, Lack of proper tools for designing & soil resistivity analysis. The soil can be in multi-layer horizontally as well as vertically. Hence before designing we should know the no. of layers in the soil so that we can use the very same data to design the multi-layer earthing grid as per real time site conditions.
To do so, we shall take the help of some computer aided software available in the world like CDEGS software. It is the software which allows us to do the design optimization along with proper design validation of the project as per real time site data.
