Optimized Design and Analysis of Grounding Grid for 400 kV EHV Air Insulated Substation

摘要

An EHV substation, Transfers power usually from the generator end to transmission level. Voltage level is stepped up to the EHV transmission level, which is more economical and efficient considering the losses and length of line. One of the most important components of the substation is a Grounding grid, which provides a ground path for all the devices and equipment. the key concern for a grounding grid is the safety of the personnel as well as of the equipment. As nowadays HV and EHV substations are much widely used due to the bulk power transmission requirements to longer distances, Safety as well as optimum operation of substation gears is to be taken into account on priority. Hence, an optimally designed grounding grid is highly necessary to meet these requirements. This work is to simulate and optimize the structure of Grounding grid for a 400kV AIS substation, respective voltage level chosen as it is most suitable today in power evacuation substations. The software used for the complete design and analysis is ETAP – Electrical transients analyzer program. The key factors effecting the Step and Touch potentials and also the grounding resistance are taken into consideration and analyzed.