Design of Earthing in Underground Substation using ETAP with Constraints

This paper describes the earthing design of a distribution substation 33kV 415V, 50Hz system. in this type of substation equipment's are 33kV HV panel, transformer, battery, battery charger and Low voltage panels. The earth mat is below substation which is almost 15 18 Meter deep from ground level. The main considerable factors for earth mat design are soil resistivity which is higher due to basalt rock and system fault current. Fault current level of the system considered as 70kA derived from calculations. Earthing is essential for proper functioning of substation equipment's and in the absence of proper designing affects in many ways like electric shock to personnel's and malfunctions and damage to the equipment's. The basic purpose of earthing is to ensure personnel safety, safe and reliable operation of equipment's, prevent stray current, protection against interferences and keeps steps and touch potential within safe limit. This paper also discussed constraint in design due to below ground level. Result of manual calculation compared with design simulated through ETAP software version 19. The data used in design considered from a substation in Mumbai, Maharashtra. Daud Ahmad | Dr. Javed Ashraf "Design of Earthing in Underground Substation using ETAP with Constraints" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd43787.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/43787/design-of-earthing-in-underground-substation-using-etap-with-constraints/daud-ahmad