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Insulation systems of electrical apparatus (fluid and solid) include transformer oil, insulating paper, glass, ceramic, mica and rubber. Normally, they are designed well to be stable at high temperatures and provide excellent electrical insulating properties in different operating loads. There is an increasing demand to modify the effectiveness and capabilities of these insulation systems to overcome various issues (e.g., overheating, overloading and short circuits). Moreover, they should match the new high voltage insulation requirements, safety, ultra-high voltage, and being environmentally friendly are some of them. Nanoparticles (NPs) are promising compensator materials that can be used to develop insulation systems with good thermophysical and dielectric properties. The results of many studies show marvelous enhancements in electrical and thermal properties. In this paper, the authors present a review that focuses on different NPs that are used in several aspects of insulation systems to improve the dielectric as well as the heat transfer properties of high voltage insulation applications. The review covers NPs types, the preparation methods, analysis approaches, different properties, performances and results, challenges, and the limitation of the use of NPs. [ABSTRACT FROM AUTHOR]

This study reports an investigation on space charge distribution and leakage current (LC) pulses of four units of glass insulators recently removed from service. Simulation works were conducted using finite element software and validated by laboratory experiments. The simulation and experimental results were found to be in good agreement when studying the space charge distribution pattern along the glass insulator string. It is evident that the LC waveform can be used to characterise the types of partial discharge according to their occurrence with respect to the AC supply. Thus, the proposed method is viable and reliable to be applied in an online measurement system. [ABSTRACT FROM AUTHOR]

Electrical treeing is one of the major breakdown mechanisms for solid dielectrics when subjected to high electric stress. It is a damaging process due to partial discharge (PD) and progresses through the stressed insulation by chemical degradation whose path resembles the form of a tree root. Numerous methods have been proposed to increase the tree resistance of the insulating materials, such as adding tree inhibitors, reinforcement, and modifying the insulating material. In overcoming this phenomenon, nanocomposites have gained broad interest as insulating materials due to their excellent ability to resist electrical treeing. Introducing nanofiller into the polymer matrix is an impressive and promising method to enhance the electrical tree endurance. In fact, this may increase the resistivity of polymer to suppress the growth of electrical trees inside the insulation medium. This article presents a study on the electrical tree performances with its associated PD and the influence of filler concentration in silicone rubber (SiR) samples filled with silicon dioxide (SiO2) as the nanoparticles for electrical treeing retardant. Previous research that used SiO2 as a filler showed lots of improvement on the breakdown test compared to the unfilled SiR, which prompted this study. The electrical tree performance of SiR nanocomposites containing SiO2 nanoparticles, however, has received limited attention. The electrical tree experiments were carried out by applying a fixed AC voltage of 12 kVrms at a power frequency of 50 Hz to unfilled SiR and SiR nanocomposites containing 1 wt%, 3 wt%, and 5 wt% SiO2 nanoparticles. The outcome parameters investigated to evaluate the electrical tree performances were tree initiation time, tree propagation time, growth rate, and tree breakdown time concerning its associated PD characteristics. This study found that the SiR nanocomposites could suppress the electrical trees better than the unfilled SiR. Moreover, increasing the filler content increased the electrical tree performances of the SiR nanocomposites. This finding suggests that the SiO2 can be exploited as a filler in SiR polymeric insulating materials for inhibition of electrical tree. [ABSTRACT FROM AUTHOR]

Insulations in the power cable system are prone to ageing and degradation, eventually leading to a complete breakdown. One of the solutions to reduce insulation breakdown in polymeric insulation is by adding nanofillers into the polymer matrices of the insulation to form polymer nanocomposites. However, the addition of the nanofiller into the polymer usually results in agglomeration inside the nanocomposites. Recently, atmospheric pressure plasma (APP) has been introduced by adopting the nanofiller's surface modification method to hinder agglomeration formation. The aims of using APP are to enhance the nanofiller-polymer interfaces and improve the dielectric properties, emphasizing partial discharge (PD) resistance and AC breakdown strength. In this study, APP has been used to treat boron nitride (BN) and silicon dioxide (SiO2) nanoparticle surfaces for the purpose of enhancing the compatibility with low-density polyethylene (LDPE) matrices. Untreated and plasma-treated nanoparticles have been added into LDPE with different filler loading of 1 wt%, 3 wt% and 5 wt% via the direct compounding method. Compared with untreated nanocomposites, the 30-minutes plasma-treated nanocomposites could improve the PD resistance by reducing the PD magnitude up to 513 pC and reducing the PD number to 11661. Moreover, the AC breakdown strength of the plasma-treated nanocomposites had increased from 0.53 kV/mm to 26.65 kV/mm. If compared to LDPE/BN nanocomposites, it was discovered that the LDPE/SiO2 nanocomposites displayed significantly better dielectric characteristics. In addition, plasma treatment of the nanoparticles could produce nanocomposites with better formulation stability and promising dielectric performance, which can prolong the insulation's lifetime and ensure the reliability of the power supply. [ABSTRACT FROM AUTHOR]

Lightning activity correlates with the formation of thunderclouds which increase the atmospheric electric field (AEF) between the cloud and the earth. Observations of the development of the AEF will allow the prediction of lightning activities close to a particular location. In research and development, the data logger plays an important role to observe and collect data from AEF sensors. The data logger must be reliable and effective. High investment costs are involved in acquiring a data logger, and choosing a suitable data logger is not easy. Institut Voltan dan Arus Tinggi (IVAT) is develeloping AEF sensor. Along with that sensor development a data logger development is also required. In this paper, a mobile data logger is developed by using Arduino-Uno. This mobile data logger is equipped with a GPS module, which provides accurate positioning in the collection of data. Laboratory and field tests were carried out to observe the performance of the mobile data logger system. The results showed that the developed data logger works properly. [ABSTRACT FROM AUTHOR]