This paper presents a health analysis technique for transformer winding insulation through thermal monitoring and Fast Fourier Transform (FFT) power spectrum. A novel thermal model for the Kraft paper insulation of transformer is proposed by using the transformer's top-oil and winding hot-spot temperature models. The relationship between the temperature rise of oil inside the transformer tank and the winding insulation degradation are considered by utilizing the data-sets and daily load cycles of a 10/13 MVA, 132/11 kV, 50 Hz, ONAF grid power transformer. The model based on IEEE Guide for loading mineral-oil-immersed transformers is developed in Simulink. The hotspot temperature rise from the thermal model is used as a reference to analyze the winding insulation degradation in the form of high frequency partial discharges (PDs) upon the output parameters of the transformer. Using data analysis techniques, a correlation is presented between the load cycles and the hot-spot temperature through which the health status of the transformer winding insulation is estimated. Moreover, the high frequency transients were detected using the Fast Fourier Transform (FFT) spectrum analyzer tool in MATLAB. The preliminary study shows that high frequency PDs are detected for the overheated and deteriorated state of the winding insulation. The results show that the proposed technique is feasible for the health analysis of power transformers and successfully predicted the deterioration of the transformer winding insulation.

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Grim issue of Electricity shortages in most of developing countries leads to explore the potential in renewable and economical sources of energy. Power generation through Waste To Energy (WTE) Plants is an effective way to deal with the problems of MSW management and electricity shortages in densely populated cities of the world. In this paper, capacity estimation of Power generation from Municipal Solid Waste (MSW) of Peshawar city through Solid Waste Fueled Power Plant (SWFPP) is analyzed. For effective estimation of power generation through WTE plant, a detail study about estimation of Municipal Solid Waste of Peshawar city, composition and characteristics of collected waste, appropriate conversion technology; heat generated from it and ultimate power generation is discussed.

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In transformers, in addition to the primary and secondary coils, there are several other important components and accessories in which the insulating material is one of the most critical components of a transformer. Sufficient insulation between different active parts are necessary for safe operation. Adequate insulation, it is not only necessary to insulate the coils from each other, or from the core and tank, but also guarantees the safety of the transformer against accidental surges, but with the growth in size and complexity of power stations, transformer is facing insulation problems. The evaluation of the transformer overload capacities certainly leads to complex variables that affect the operating life of the power and distribution transformer. In this study, the long-life calculation is performed on the basis of two experiments, which are related to the insulation degradation of the mineral oil and cellulose paper such as by adding different types of nano-particles to the mineral oil to enhance the strength of oil, and by changing the loads under different operating conditions to control the deteriorating rate of the insulation to prevent the life of the transformer. The insulation breakdown strength is improved from 37 kV to 71 kV by mixing the semiconductor nanoparticles such as gadolinium-doped ceria (GDC) and cerium dioxide (CeO2) with mineral oil. Moreover, for cellulose paper, thermal degradation rate is kept below its limit by reducing the temperature when controlling the load.