Cross-linking byproducts are suspected to be the main contributing factor in space charge formation observed in XLPE. To investigate the mechanism behind this phenomenon, low density polyethylene was soaked into three main crosslinking byproducts, acetophenone, -methylstyrene and cumyl alcohol, and space charge measurements were performed using the Pulse Electroacoustic technique (PEA). It has been found that soaking LDPE in cumyl alcohol introduces more charges into the system, with homocharges and heterocharges accumulating within the sample compared to the additive free sample. In contrast, -methylstyrene and acetophenone reduce the amount of accumulated charges. In terms of charge decay, all three byproducts enhance the decay process in the insulator. Further investigations were conducted in conditions where two byproducts are present in a sample. The results shows that acetophenone is a dominant byproduct in determining the charge density patter built up during the charging process, whilst the rate of charge decay is observed to be high in the presence of -methylstyrene in the sample.

Abstract-The need to find ways to effectively utilize the large quantities of agricultural waste that are produced is indicative of the huge potential associated with producing an alternative pyramidal microwave absorber for anechoic chamber-testing applications. We propose the development of a pyramidal microwave absorber that can use sugar cane bagasse (SCB), a byproduct from the production and processing of sugar cane, as the absorbent. In this paper, we report the results of our use of dielectric probe measurement to determine the dielectric constant and loss tangent of SCB. These values were used to model and simulate an SCB pyramidal microwave absorber in Computer Simulation Technology's (CST's) Microwave Studio. This absorber was operated in the microwave frequency range between 0.1 GHz and 20.0 GHz.

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The transformers oil acts as an insulation as well as cooling liquid of a transformer. It is very important that the transformer oil is maintained so that the oil properties are preserved with time. Petroleum-based mineral oil is widely used as insulation oil in transformer due to its excellent insulating qualities and low cost despite its’ non-biodegradable and hazardous property. This paper seeks to find an alternative of mineral oil by using palm oil based nanofluids at lower concentration values that match the IEC standards for ester oil. The nanoparticles used in this project are zinc oxide (ZnO) and zirconium dioxide (ZrO2). ZnO has conductive nature while ZrO2 on the other hand shows insulative behavior. Three different concentration value were used which were 0.0015 g/L, 0.0025 g/L and 0.005 g/L which had never been reported before. Tests performed on the samples includes AC breakdown, dielectric properties and kinematic viscosity. Research outcome shows an outstanding result at optimum value in improving the measured properties at these low nanofluid concentrations. Reducing the amount of nanoparticles use also means saving cost and providing a more eco-friendly solution.

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