Failure of Short - Circuit Generators: A Case Study by CPRI, Bhopal

Switchgear Testing and Development Station prevalently known as STDS was established in 1965 at Bhopal by the Government of India as one of the units of Central Power Research Institute. The predominant objective of setting up this institute was to cater the short-circuit testing needs of various LT/HT power equipments in switchgear, controlgear and transformer fi eld. Over the years, the unit has expanded and received all the national/international accreditations, and further became the member of Short Circuit Testing Liaison (STL). Today, CPRI’s short circuit laboratories of generator based and direct on-line based are one of the leading laboratories in south east Asia.

Year 2006–2007 was a test time for CPRI, Bhopal, when both the short-circuit generators have developed technical snag, resulting in an interruption of short-circuit testing. It was a challenge for CPRI as well as for the service provider to take repair work, as so many technical intricacies were involved including the reverse engineering process. Nation realized the importance of CPRI during the shutdown period. This paper discusses about the occurrence of failure, its detailed diagnosis, ischolar_main cause analysis and the action taken thereafter. Short-circuit generator is different from conventional one in many aspects. Repairing experiences of these generators, along with the re-commissioning process, are also shared herewith.