Transformer liquid dielectrics evolved where mineral oil has been the dominant choice until emergence of synthetic esters and natural esters. Natural ester-based oils have been under extensive investigations to enhance their properties for replacing petroleum-based mineral oil, which is non-biodegradable and has poor dielectric properties. This paper focuses on exposition of natural ester oil application in mixed transformer liquid dielectrics. Physical, chemical, electrical, and ageing characteristics of these dielectrics and the dissolved gas analysis (DGA) were reviewed. Physical properties include viscosity, pour point, flash and fire point which are vital indicators of heat insulation and fire risk. Chemical properties considered are water content, acid number, DGA, corrosive sulphur, and sludge content to limit and detect degradation and corrosion due to oil ageing. Electrical properties including breakdown voltage were considered for consistent insulation during overload and fault conditions. These properties of evolving alternative dielectrics were reviewed based on ASTM International standards and International Electro technical Commission standards for acceptable transformer liquid dielectrics. This review paper was compiled to avail modern methodologies for both the industry and scholars, also providing the significance of using mixed dielectrics for power transformers as they are concluded to show superiority over non-mixed dielectrics.

The protection of turbine generator systems is an important factor that must be considered in power plant for efficient production of electricity. This project deals with temperature level monitoring of the power generator and it will be compared with the predetermined standard value through an LM35 sensor. Once it exceeds the predetermined value then the cooling fan will automatically turn on which will be useful to prevent the generator from internal winding thermal failure. The protection system consists of 16x2 LCD display, LM35 temperature sensor, a coolant fan and a microcontroller [ATMEGA328P]. The internal winding temperature of generator is increased as the turbine is rotated at its axis which may lead to major damages in the axial position and shafts of the power generator. To overcome this, an LM35 sensor is connected and linked with the microcontroller which monitors the temperature and once it exceeds the standard temperature the coolant fan automatically is turned on by the microcontroller and the heat of the steam will be countered by the cooling air produced by the coolant fan. The fan runs continuously until the temperature is sensed to have dropped below the standard temperature. At the same instances, the LCD display outputs readable current temperature parameters for the operator. The protection of power generator system is a vital component in power plant for efficient production of electricity.

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The project is to Design and Develop an OFF-GRID solar photovoltaic System using DC-DC Topologies for BIUST classrooms light loads (lighting, projector, and computer). Narrowing this topic, focus is on harvesting solar energy using photovoltaic cells then boost the power using a DC-DC boost converter. This project consists of different subsystems, which are combined to have the solar system for classrooms light loads. These are Photovoltaic Solar Array, Maximum Power Point Tracking (MPPT), DC-DC boost converter and battery bank stores energy to be used when the sunrays are not efficient to supply the load. Lastly a DC-to-AC inverter is designed. The system is design is based on performed calculation to size each component to keep the system efficiency high. According to simulation of different DC-DC converters using Simulink, boost was the best converter to use looking at the output characteristics desired. Results from Proteus software simulation of the final circuit correspond with expectation from literature review. Furthermore, PVsyst software has been used to do the mathematical analysis of the designed model showing an estimated payback period of 2.6years whereas the output power for PVsyst model is 11.9 kW which the system produces given the design parameters calculated.