The Insulation Diagnostics Laboratory was established in the year 2006-2007 in the Electrical Engineering Dept. of IIT Bombay. It is intended for academic and research purpose. There is 100 kV AC/140 kV DC test setup with Partial Discharge Measurement facility. Additionally, special purpose instruments such as oscilloscopes, LCR meter, spectrum analyzer, function generator, and current probe are available.
The academic activities include giving exposure to undergraduate and postgraduate students about various high voltage engineering aspects. Study of corona inception voltage for various electrode arrangements, demonstration of frequencies radiated by corona are some of the experiments conducted as part of academic activities. A transformer tank like structure having a provision of changing electrode arrangement, present inside it, has been fabricated for experimentation. The effect of tank on captured UHF corona pulses is currently one of the topics of research in the lab. Statistical analysis of partial discharge/corona pulses is generally reported in the literature for explaining the intricacies of these processes. Digital equipment capable of recording these pulses is expected to help the students move their research in that direction. Parallel development of the laboratory as a diagnostic centre for power systems equipment is also envisioned. With this objective in mind, the capability of performing winding dislocation detection and analysis is also being actively pursued. For this purpose, four coils [Courtesy: M/s Crompton Greaves Ltd.] are available for experimental works. These coils have different winding patterns for performing the industry standard Frequency Response Analysis (FRA). Also a new, better and more accurate method have been developed in the lab for the same purpose
The distinguishing feature of the Lab is its Faraday cage that has been erected to reduce the to and fro interference. It has been designed from scratch, by referring to the literature and talking to several experts at national/international level in the field of high voltage. The cage stands on a frame of mild steel, and is made of electrolytic grade aluminum. It has proven to be highly effective and has reduced the ambient partial discharge from 17 pC to under 3 pC. Being a teaching lab too, many special precautions in addition to the regular high-voltage related protection have been taken for safety. There is auto-earthing arrangement that gets activated, each time the HV transformer is denergized or if it trips. A door limit switch, that doesn't allow energization of the transformer unless door of the faraday cage is closed. Another recently added device checks the earthing arrangement before start of HV experiment. If either of these devices senses a failure, it does not allow energization of the HV transformer.