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Daily life is characterized by a great explosion of abundance of information available on the internet and social media. Smart technology has radically changed our lives, giving a leading role to social media for communication, advertising, information and exchange of opinions. Managing this huge amount of data by humans is an almost impossible task. Adequacy…

The ageing of oil-immersed power transformers triggers several defects and damages in the insulating materials, particularly in the cellulose insulation. The decomposition of the cellulose paper produces dissolved gases into the insulating oil, in which the Dissolved Gas Analysis (DGA) of the oil samples can provide insights to incipient faults sustained by the transformer as…

In the last decade, South Africa has attracted and attained more investment by means of the Renewable Energy Independent Power Producer Procurement Programme (REI4P), which is, a structured invitation to Independent Power Producers (IPPs) to submit a bid to generate and supply power to the electrical grid. In spite of REI4P’s undeniable triumph, a much-discussed…

Transformers are habitually designed and manufactured for operation at a fundamental frequency of 50Hz and sinusoidal load current. Transformers are susceptible to non-linear loads. The inception of switching action characterises Non-linear loads and consequently nonsinusoidal load current which brings about higher transformer service losses, hotspot temperature rise, and degradation of cellulosic and liquid insulation, and…

Distributed Solar Photovoltaic (DSP) Plants are one of the fastest growing renewable energy systems in South Africa. The primary components forming an integral part of the point of common coupling (PCC) are, the inverter used to convert dc voltage to ac voltage and step-up transformers which step-up low voltage input to the desired output level.…

The rapid transformation of the energy sector in South Africa towards renewable energy (RE) production calls for the management of assets to keep pace with the ongoing developments in a reliable manner. Aging assets, increasing energy needs and reliable supply of energy without load shedding are some of the challenges utilities are facing in South…

South Africa is aiming to achieve a generation capacity of about 11.4GW through wind energy systems, which will contribute nearly 15.1% of the country’s energy mix by 2030. Wind energy is one of the principal renewable energy determinations by the South African government, owing to affluent heavy winds in vast and remote coastal areas. In…

To this extent, the delineation of techno-economic evaluations for transformers becomes more intricate through a lens of Distributed Solar Photovoltaic (DSPV) market in South Africa. Essentially, the transformer price and loss evaluation techniques should be tailored for calculating the Total Ownership Cost (TOC) of transformers facilitating decentralized energy systems. In South Africa, the traditional coal…

Large power transformers generally include a customer request for a technically appropriate regulation unit. The selection process of the regulation unit consists of defining the required input data, performing mathematical calculations necessary to find the technical limit values that the regulation unit has to satisfy, and finally optimizing and selecting the appropriate regulation unit. The…

DC power is apparently attempting to breach into the power system – the system which it once lost to the AC power paradigm. DC is already present in the generation, transmission and utilization sides of the system, leaving distribution as the only area where it has not shown any significant presence – this may be…

Reliable operation of a power transformer with a certain load depends on the technical condition of individual construction parts and the ability to prevent defects that can cause a failure. During the lifecycle of a transformer, valuable data is constantly accumulated, which forms the basis for technical or risk assessment of the equipment. Therefore it…

This paper proposes the modeling and control of a Solid-State Transformer using a three-stage conversion topology. First, a rectification stage is used, where a three-phase high-voltage AC signal is converted to a DC level; this stage is then followed by a DC-DC converter, and finally an inverter is used to convert the DC into a…

A3S(Arwin-Adang-Aciek-Sembiring) is a method of information fusion at a single observation and OMA3S(Observation Multi-time A3S) is a method of information fusion for time-series data. This paper proposes OMA3S-based Cognitive Artificial-Intelligence method for interpreting Transformer Condition, which is calculated based on maintenance data from Indonesia National Electric Company (PLN). First, the proposed method is tested using…

High frequency planar transformer is a new type of transformer that operates at high frequency. Its significance is proved through its miniaturised features, high power density and other performances. The design of planar transformer needs to consider several fundamental factors, including core material, dimension of layers and winding pattern. As the volume decreases, extra attentions…

This article enhances discussions on Generative Artificial Intelligence (GenAI) and prompt engineering by exploring critical pitfalls and industry-specific advantages. It begins with a foundational overview of AI evolution, emphasizing how generative models such as GANs, VAEs, and Transformers have revolutionized language processing, image generation, and drug discovery. Prompt engineering is highlighted as a key methodology…

Condition assessment of medium voltage assets is essential to ensure reliability and cost-effective operation of power distribution networks. This article presents a literature review of condition assessment of medium voltage assets related to a distribution system in a non-interconnected zone in Colombia, namely, power transformers, photovoltaic systems, switchgear, lines and cables, and instrument transformers. Advanced…

The paper describes the control and monitoring systems installed in medium voltage networks by Polish distribution network operators. It also outlines the expected directions of development of these systems, specifies the functions of the individual system components and describes the requirements applicable to them. In particular, attention is paid to the implementation of functions to…

We propose and analyze new impedance matching schemes to enhance applied voltage to an optical modulator and light modulation for a subcarrier multiplexed light transmitter or a radio-on-fiber transmitter that carries radio-frequency signal through an optical fiber. Our proposal includes two methods using a quarter-wavelength impedance transformer and a tapered microstrip line for impedance matching…

Gate driver has been applied in many ways, exemplified by that, by using the DC-isolated and AC-pass characteristics of gate driver’s primary and secondary sides, the problem of floating endpoint in semiconductor power switch can be solved. However, the conventional design of isolated gate driver provides circuit voltage blocking by optically coupled components. Due to…

This article aims at comparing two controls to follow the maximum power point, making use of DC-DC converters for PV uses. All transformers operate continuously. To fulfil maximum power, we will exploit two MPPT controls: a traditional perturb – observe ‘P&O’ and a smart one – the fuzzy logic ‘FL’. The goal of this article…

In this study, we developed and evaluated an automatic abstractive summarization algorithm in Japanese using a neural network. We used a sequence-to-sequence encoder-decoder model for practical purposes. The encoder obtained a feature-based input vector of sentences using the bidirectional encoder representations from transformers (BERT) technique. A transformer-based decoder returned the summary sentence from the output…

Transformer health assessment techniques, based on applicable standards, such as the dissolved gas analysis (DGA), through laboratory testing or online monitoring are used to analyze the symptoms of a failure which develops in transformers from an early stage. The DGA from a sample of dielectric liquid taken from the main tank generates information on the…

The undulated power supply has dropped to its worst reliability index in most parts of the city despite the installations of distribution transformers to improve the power. In this work, examination of Port Harcourt Town Zone 4 (Z4), Rivers State power distribution system forcing on its operation, planning for future expansion of the system, and…

The insulation condition of a transformer decides the longevity of the equipment. The unpredicted failure of power transformer will lead to major disaster in the distribution network and it affects both environment and public safety. Nowadays synthetic oil and natural esters are alternatives to transformer oil because of the biodegradable nature. In this paper, investigations…

Nigerian power utility companies particularly the distribution and generation aspects were recently in the process of national power reform converted from public to private service by privatization. Prior to these development, power utility companies’ performance is low due to poor operational style that leads to inadequate revenue generation. Thus, the task before the privatized companies…