Earth Mat Design Ppt

The grounding system in substation is very important.

Earth mat design ppt. Design procedure of earth mat increase in horizontal conductor length actually reduces touch potential. The substation earthing system comprises of a grid earth mat formed by a horizontal buried conductors. So we have to effectively use conductor and down rod to minimize the step and touch potential within mat zone and beyond of. Read about design of substation earthing system here.

Content uploaded by omeje crescent onyebuchi. Earth mat design for 132kv substation in rivers state using etap pdf. In this design these additional rods or mats are made to bond with the existing main ground mat and thereby assist in achieving the desired results. Chemical electrolytic ground electrodes provide a low grounding resistance in areas of high soil resistivity and low.

Such type of system helps in limiting the ground potential. It is well that the earthing systems are intended to protect equipment and personnel in and around the substation from the dangerous over voltage. In high and medium voltage air insulated substations ais the electromagnetic field which causes are the static charges of bare cable and conductors and by the atmospheric conditions surges induce voltages at no live parts of the installation that create potential differences between metallic parts and ground and also between different points of. The wenner and schlumberger test methods are both recommended with testing and interpretation.

Increase in no of mesh in mat reduces the touch potential but beyond certain limit the mat is said to be saturated. Standard crowfoot earth 25mm x 3mm copper tape x 5m long joined to a 70mm2 bcew tail 2m long. It reduced the overall grounding resistance. Increase in no of down rod reduces step potential.

Can t do the earth mat design separately for each step and finally connect each steps together. Earthing mat is made by joining the number of rods through copper conductors. Earthing mat design for hv ehv substations. While designing an earth mat the following step is taken.

Use of e mix a conductive earthing compound with earth mats will always improve the earth resistance. Introduction to substation earthing grid. Driven chemical electrolytic ground rod. Could u please explain me how to do the earth mat design for 220 132 33 kv outdoor gss which have 5 steps 135m 138m 141m 144m 147m.

As earthing systems are installed near the surface of the earth the top soil layers being subject to higher current densities are the most significant and require the most accurate modelling. Earthing mat is mostly used in a placed where the large fault current is to be experienced.