Eight research projects including 03 sponsored, and 05 internal projects were completed during the year. 

Brief summary of the work done in some of the major projects are given below: 

4.1       Project No: SP 012-043
“Establishing correlation between non-linearity in supply voltage, load current and transformer losses”
(Sponsored by Ministry of Power, New Delhi)

This project was undertaken in order to evaluate and compare the performance of transformers made up of two different core materials namely, CRGO and amorphous metal under harmonic conditions.  While the criteria for evaluation of the transformer load losses while feeding non-linear load current are well defined in IEEE Std C57.110-1998, it is not so for the core losses.  In this project, an effort has been made to evolve methodology for computation of core losses with distorted voltage waveform, the methodology is independent of design data.  The benefits are to utilities in selection of site-specific optimized performance of transformer.  Various experiments were conducted on two transformers (10 kVA, 440 V/440 V single phase transformers) having different cores (Amorphous and CRGO) but coil construction such as to keep coil losses same.  The results obtained after conducting these tests are encouraging.   

4.2    4.2  Project No: IP 040-060 

Water Soluble Polyester Enamel for Winding Wires 

Polyester enamel available in the market has organic solvents.  A large number of organic solvents are widely used in the manufacture of enamels, varnishes, paints, inks, coatings etc.  Wire enamels made for continuous operation at temperatures above 150^oC require aromatic solvents such as cresol, cresylic and phenol, hydrocarbon elements etc., which are very harmful in nature.  These solvents pose several problems like pollution, waste disposal problem, fire and health hazards.  Therefore, alternatives to these solvent based magnet wire coating compositions are sought which will reduce the emission of volatile organic compounds (VOCs) in the environment.

In this project, new eco-friendly water-soluble polyester resin has been synthesized and evaluated as per IS: 13730.  Due to the absence of conventional organic solvent, this coating is eco-friendly and non-toxic.  It has been found to meet the requirements of enameled wire as per Indian Standard. 

4.3       Project No. SP 040-087

“Development of Electrical Grade Putty” (Sponsored by : Polymer Specialities, Kerala) 

Electrical grade insulation Putty finds wide sealing application in electrical industry.  In addition to providing good electrical insulation, the putty also acts as a barrier to moisture penetration, extraneous matter and other environmental pollutants.  The putty is generally a two – component system, which cures upon the application of heat and forms a solid mass.  It remains in this state until destroyed due to repairs or any other reasons. 

M/s. Polymer Specialities, Kerala approached ERDA with a request to develop putty having good electrical properties and also meeting the requirement that it must remain soft throughout its service life.  ERDA accepted this challenging task and developed soft putty, conforming to all the technical specifications laid down by the sponsor.  It is particularly intended for marine application.