Importance of Transformer Neutral Earthing in a Substation – A Case Study Prabhakar C1, Nagachandra Bandi Venkata1, Pauly P Jithin1, Pandian G1 1High Voltage Division, Central Power Research Institute, Bengaluru, India Online Published on 29 February, 2024. Abstract The earthing system in a HV substation consisting of power transformer neutral, Lightning arresters, Current transformers, Potential transformers and metallic body parts of the equipment etc. The effectiveness of earthing system for reliable operation of power systems depends on proper maintenance of earthing system at regular intervals. As part of regular operation & maintenance, measurement of earth resistance at regular intervals is very much essential to check the healthiness of the earthing system. In most of the substations, correct practice of measurement of earth resistance is not being followed. Because of the improper measurement of earth resistance of earthing system in a substation leads to most of the failures of the equipment and one such major failures is the failure of transformer. As the general practice, efficacy of earthing system is carried out in order to ensure that the earthing system is effectively bonded to all the equipments. This paper describes the importance of transformer neutral earthing and best practices to be followed in measurement of earth resistance during evaluation of earthing system in a substation which will be an insight to personnel for proper diagnosis of failure of system due to improper grounding. Top Keywords Earthing system, Transformer Neutral Earthing Earth resistance, Substation. Top |