Testing of transformers for transferred surge - A key tool for verifying design and manufacturing

In electrical power system transformer is the key equipment Special care and attention is required during design, manufacturing, commissioning and even in service life of transformer.

Various tests are performed on the transformer to identify condition of transformer at various stages Relevant standards specify list of such tests to ensure specified design, manufacturing and satisfactory working of transformer.

It is fact that transformer is transforming voltage from one level to other level according to its transformation ratio Similarly, surges are also transferred from winding to windings

This paper deals with requirement, application of transferred surge test and study on adoption of higher impulse voltage withstand levels by Gujarat Energy Transmission Corporation (GETCO) The test suggested in this paper be considered as a tool to ensure specified design and quality of transformer

It also covers the case study on the transformers of GETCO under procurement GETCO has adopted BIL of 350 kVp for 66 k¥ system even though 325 kVp is permissible as per standards The methodology referred herein this paper justifies this adoption