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The increase in demand of electricity throughout the world and depleting fossil fuel have proved to be a hurdle in the path of development. In addition environmental aspects of fossil fuel would make the existence of civilisation a difficult task. The design of renewable energy sources have gained much significance in reducing the dependency on fossil fuel. Multiple methods have been utilised for obtaining a feasible combination of renewables. Present work studies one such design optimised by HOMER for a lab facility (at NERIST) Nirjuli, India. The chosen location has sufficient solar energy, trapping off this resource would help in solving power issues. Various cases of interlinking of energy sources are considered and their respective expectancy in terms of meeting up of loads, cost, carbon dioxide emissions and fuel consumption have been observed.

The forces exerted due to the transient currents in a power transformer can result in deformity of core and winding. These transient currents are the excessive current arising in the transformer at the time of short-circuit fault. This study aims in examining the axial and radial force generated in the transformer's high voltage winding and the deformations associated with it when a double line short-circuit fault occurs. The analysis has been done for a three phase 11/66 kV power transformer of 40 MVA. Finite element method is employed using COMSOL Multiphysics. The electromagnetic force study is significant in determining various design parameters of the power transformer so as to protect it from the harmful effects taking place due to the transience in currents.

The work emphasises on the thermal behaviour of a High Voltage DC transformer on the occurrence of DC bias in the system. The DC bias can lead to temperature rise in the transformer and can form hotspot in the windings which may result in various issues including thermal breakdown among others. A two-dimensional design of the core and windings of the converter transformer is modelled using Finite Element Method and is considered for studying the thermal behaviour due to the presence of DC bias. The results are curve fitted to obtain a sigmoidal function describing the variation of hotspot temperature with respect to applied DC bias. The developed function is validated by choosing different values of DC biases. Besides, the statistical significance of the function has also been evaluated. The obtained results are encouraging in the prediction of the hottest spot temperature.