In a first, state power utility Madhya Pradesh Power Transmission Company Ltd (MPPTCL) has deployed transformers equipped with advanced RIP (resin impregnated paper) bushings in place of the conventional OIP (oil impregnated paper) bushings.
RIP vs OIP
With the help of RIP bushings, MPPTCL expects to control the failure rate of transformers as conventional OIP bushings are known to have a higher failure rate. Conventional oil and paper (not resin impregnated) bushings tend to absorb moisture even after various protection measures. This becomes the main cause for transformer failure.
On the other hand, RIP bushings contains a resin medium that helps maintain for a very long time the original internal transformer parameters – mainly tan delta that represents the non-conducting capacity of the bushing. This helps in minimizing the occurrence of sudden transformer failure. RIP bushings therefore ultimately increase the availability and reliability of the transmission system.
Two substations
These RIP bushings have been deployed in two new 160 MVA, 220kV transformers at the 220kV substations at Narmada Puram (Bhopal) and Kukshi (Indore).
Widespread use
While MPPTCL has started using RIP bushings in 220kV and 400kV transmission systems, the utility soon plans to incorporate such advanced bushings in 132kV transformers as well.
Also read: Godrej & Boyce Commissions 220kV Substation In Karnataka
Perseverance
According to Ajay Srivastava, Chief Engineer, MPPTCL, the longstanding challenge of replacing traditional bushings with innovative ones was accepted by the engineers of the utility’s procurement facility.
Iqbal Khan, Executive Engineer – Procurement, MPPTCL, studied the working of these bushings in different parts of the world and also consulted various technical papers on the subject. After a long stint of perseverance, MPPTCL was able to prepare safe and effective technical specifications for manufacturers to supply these RIP bushings for transformers of 220kV or higher, in the first phase.
Featured photographs shows the RIP bushings-equipped power transformer at the 220kV Narmada Puram substation in Bhopal.
