Study of causes of failure of power transformers and significance of adequate earthing (Grounding) in mitigation of hazards in substations Dr. Arora Rajesh Kumar Delhi Transco Ltd (DTL), Delhi, India Online published on 15 April, 2023. Abstract The transformer, being a key element in the transmission and distribution of electrical energy, improving its reliability is of utmost importance. System abnormalities, loading, switching and ambient condition normally contributes towards accelerated aging and sudden failure. Hence, it is, all the more essential, to employ-continuous monitoring techniques and on-site diagnostics followed by quality maintenance for having trouble free and reliable operation with minimum outages and fire hazards. Also use of adequate grounding helps to mitigate the fire hazards and accidents. The main objective of grounding electrical systems is to provide a suitably low resistance path for the discharge-of fault current which ultimately provide safety to working personnel and costly installed equipments in the substation. The flow of heavy fault current results in rise of potential in the substation area and with respect to-remote ground. There is need to ensure that the ground potential rise, and touch and step voltages are within permissible limits. This paper provides an overview of the causes leading to failure as well as fire in power transformers and discusses the importance of grounding of transformers and other equipments in substations to avoid hazards of fire as well as accident. Top Keywords Power Transformer, Grounding, Step and Touch Potential, Fire in Transformer and Electrical Accident Prevention. Top |