Informatics Publishing Limited

K. Karunakara ¹, P. N. Ashitha ², S. Ganga ³

Affiliations
1 Joint Director, Heat Run Test Laboratory, Insulation Division, Central Power Research Institute, Bangalore - 560 080, IN
2 Engineering Officer, Insulation Laboratory, Central Power Research Institute, Bangalore - 560 080, IN
3 Additional Director, Insulation Division, Central Power Research Institute, Bangalore - 560 080, IN

Abstract

Commonly used grades for transformer core stampings are Cold Rolled Grain Oriented Steel of grades M3, M4, M5 and M6. As the flux density increases, the magnitude of no load loss and no load current increases. But studies also indicated that, a given magnitude of core loss can be attained with both high and low magnitudes of no load current. This result can be used to ascertain the presence of inferior grade core material. It is essential to operate the transformer in the linear region of BH curve. Operation in saturated state will result in increased no load current which in turn will have a detrimental effect on the temperature rise of transformer as additional I2R losses are generated. With the limits of temperature rise being more stringent in IS standard than in IEC, the choice of flux density is crucial. In this paper an attempt is made to realize the best operational flux density, which gives a benchmark for deciding the magnitude of no load current and the corresponding no load power factor.

Keywords

No load losses, copper losses, temperature rise, CRGO

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N. V. Lahari ¹, S. Ganga ²

Affiliations
1 Project Associate, Insulation Division, Central Power Research Institute,Bangalore, IN
2 Additional Director, Insulation Division, Central Power Research Institute, Bangalore, IN

Abstract

Solar energy is considered to be one of the prime sources of renewable energy for the generation of electrical energy, which is gaining the importance in recent time in India and there is a plan to generate 200GW of solar energy by 2024. Solar energy is absorbed by Photo-Voltaic (PV) cells and converted into electrical energy. Such PV cells are connected in series and parallel combination to generate required output power. Hence, Photo-Voltaic (PV) modules must be in operation for long time without any reduction in output and efficiency. In recent times, to achieve this, both surfaces of PV module are encapsulated by Ethylene-Vinyl-Acetate (EVA) polymer, but UV radiations leads to degradation of EVA polymer, which results in deterioration of PV module, thus overall efficiency and output of module reduces. Various UV accelerated ageing studies and investigations have predicted service time of module. The objective of this investigation is to review the available literature with respect to types of PV cells & encapsulant used, UV ageing parameters & instruments employed and envision a way forward in employing EVA with nano additives as an encapsulant to improve its performance.

Keywords

Solar energy; Photovoltaics; Ethylene-Vinyl-Acetate polymer;Encapsulation; Accelerated UV ageing

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S. Ganga ¹, N. Vasudev ¹, V. Asai Thambi ¹, R. S. Shivakumara Aradhya ¹, A. Sudhindra ¹

Affiliations
1 Central Power Research Institute, Bangalore-560080, IN

Abstract

This paper presents experimental results obtained on tracking and erosion resistance of Silicone rubber (SIR) with and without pollutants. The IEC-60587 Inclined Plane Tracking and Erosion Test method combined with UV radiations of different intensities was employed to assess two different formulations with same base polymeric material (SIR). The hydrophobicity recovery property of silicone rubber formulations before and after inclined plane tracking test was studied besides the effect of corona. Some of the physical, thermal and electrical properties were compared before and after inclined plane tracking test. It is inferred from the analysis carried out on the experimental results that the intensity of UV radiation plays a major role in deteriorating the surface characteristics of the material. It is also found that the introduction of UV in the test method has helped in distinctly evaluating polymeric materials. The effect of two different pollutants was not the same on formulations considered for the study, which implies that the additives play a dominant role in the overall performance of the material than the base polymer. The study also revealed that a formulation with a better performance under a certain pollutant need not have to behave the same way under a different pollutant. Presently, CIGRE Working Group (WG D1.14) is active in standardization of material aspects besides developing suitable methodology for the testing of polymeric materials for outdoor insulation application; the inferences appear to be an useful input to both CIGRE working group and International Electro technical Committee (IEC TC 15 PT 2).

Keywords

Inclined plane tracking IEC 60587, UV radiation, Silicone rubber, Pollutant

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S. Ganga ¹, P. M. Mathiyoli ¹, K. P. Naachimuthu ¹

Affiliations
1 Department of Psychology, PSG College of Arts & Science, Coimbatore, Tamil Nadu, IN

Abstract

Food, which was once a survival need, now transformed into a material of lavishness and comfort. Both the food & food industry underwent drastic changes in the past few decades and the ecological, social, psychological, economical and biological impact it brought about is devastating. All this started when humans got struck in a luxury trap; a trap which is called Wheat in its changed appearance which is widely consumed in the form of refined flour (otherwise called Maida). Maida a waste introduced in the diet of human beings only a few centuries ago managed to evolve into a billion dollar industry and made a permanent mark in the lifestyle of human beings. But the physiological, psychological and ecological impacts caused by this waste already have an adverse effect on the current generations and will definitely take a toll on the generations to come. Despite knowing the damage caused by this waste, no strong action was taken for it, till date. Maida has become a perfect example of self destructing and invasive product to human beings. Still the Homo sapiens have a chance to save themselves from this disaster by changing their existing pattern of life/food habits. The present paper thus discusses the physiological, psychological and ecological impacts of this anthropogenic unhealthy food habits.

Keywords

Maida, Refined White Flour, Gluten Factor.

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K.P. Naachimuthu ¹, S. Ganga ², P.M. Mathiyoli ³

Affiliations
1 Assistant Professor, Department of Psychology, PSG College of Arts & Science, Coimbatore, Tamil Nadu, IN
2 Undergrad Student, Department of Psychology, PSG College of Arts & Science, Coimbatore, Tamil Nadu, IN
3 Student of LLB (Hons), School of Excellence in Law, Chennai, Tamil Nadu, IN

Abstract

Homo sapiens who originated on this Earth, a few million years ago are the only known advanced intelligent race in the Cosmos. Being evolved with a hard-wired impulse for connection, these social beings are now forced to lock themselves in isolation to contain the infectious virus which is wiping out a significant number of this species. Adhering to the strict rules and regulations across the world prohibits people from having social connections, which will severely impair the mental health, affect the economy, and alters the societal structure. This article analyses the impact that lockdown and social distancing have on the mental health of the people and its long term effects on different walks of life. It also brings to the forefront the various societal changes that happened during the lockdown and analyses the probable changes that are yet to come in the near future. This article will also give a glimpse on the new normal in practice and will make the readers think / reflect on a longer time-scale about the society which is being reconstructed, and the succeeding impacts of changes that are being imposed in the society.

Keywords

COVID 19, psycho-social impact, social behavior, consumption / spending pattern

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