Case studies of failure of power transformer - Analysis thereof

Power Transformer is a key equipment in any switchyard of power installation. Failure of any Equipment of Switchyard/Sub-station causes major disturbance in the power network. Failure of power transformer causes not only longer power outage but also causes huge economical losses due to its capital /repairing cost. The paper presented here refers to consideration of root cause analysis of failure of power transformer particularly from power system viewpoint. Many of the analysis are carried out through state-of-the-art software. The outcome of this type of study can be great learning for designer of transformer and substation as well and also may be useful for Research and Development. By application of engineering knowledge and references, the problems can be well tackled.

The paper describes analysis on the failure of power transformer of 400/33kV and 220/33kV class based on actual experience of the author. The purpose of this paper is to bring awareness amongst the stakeholders and not to disclose any installation practice or negligence. Therefore, to maintain confidentiality some of the points like place, values of parameters and a few others are described in general.