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Nowadays the reliable availability of electricity is expected by both industrial and residential consumers. However, the generation, transmission and distribution all pose engineering challenges in adapting to consumers and sustainable directives while maintaining operational safety. The increasing demand for electricity on the consumer side and the growing number of renewable energy sources (RES) on the generation side are supporting the spread of capacity uprating methods. Dynamic Line Rating (DLR) is a novel, cost-effective line management method with which system operators are able to utilize existing power lines with greater efficiency than with traditional techniques. While the use of DLR has many benefits, there are also challenges that system operators have to cope with at system-level implementation. One of the most significant of these challenges is to find the balance between the required infrastructure for DLR implementation and the reliability of the implemented system. The aim of this article is to present a novel methodology for critical span identification based on which the sensor measurements accurately represent the prevailing conditions along the whole overhead line. Contrary to current methods, the proposed critical span analysis method takes into account the clearance of the conductors, which provides compliance with legal requirements. Furthermore, the uncertainty caused by using weather data to determine local conductor annealing is also eliminated with the recommended method. This way a flexible power system can be created that meets current needs, such as the integration of renewable and distributed energy sources or cross-border energy trade, while at the same time it enhances the operational safety of overhead lines.

This paper aims to represent when the primary lightning protection is not necessary for a photovoltaic power plant with a special dimension if the different security objects are not negligible during the probability and risk calculations. The calculations were made using the Probability Modulated Attractive Volume theory which is capable of special, complicated, or huge structures and objects like a high-performance photovoltaic park.

BACKGROUND: During the COVID-19 pandemic, the importance of reliable public health data has been highlighted, as well as the multiple challenges in collecting it, especially in low income and conflict-affected countries. Somalia reported its first confirmed case of COVID-19 on 16 March 2020 and has experienced fluctuating infection levels since then. OBJECTIVES: To monitor the impact of COVID-19 on beneficiaries of a long-term cash transfer programme in Somalia and assess the utility of a syndromic score case definition and rapid mortality surveillance tool. METHODS: Five rounds of telephone interviews were conducted from June 2020 - April 2021 with 1,046-1,565 households participating in a cash transfer programme. The incidence of COVID-19 symptoms and all-cause mortality were recorded. Carers of the deceased were interviewed a second time using a rapid verbal autopsy questionnaire to determine symptoms preceding death. Data were recorded on mobile devices and analysed using COVID Rapid Mortality Surveillance (CRMS) software and R. RESULTS: The syndromic score case definition identified suspected symptomatic cases that were initially confined to urban areas but then spread widely throughout Somalia. During the first wave, the peak syndromic case rate (311 cases/million people/day) was 159 times higher than the average laboratory confirmed case rate reported by WHO for the same period. Suspected COVID-19 deaths peaked at 14.3 deaths/million people/day, several weeks after the syndromic case rate. Crude and under-five death rates did not cross the respective emergency humanitarian thresholds (1 and 2 deaths/10,000 people/day). CONCLUSION: Use of telephone interviews to collect data on the evolution of COVID-19 outbreaks is a useful additional approach that can complement laboratory testing and mortality data from the health system. Further work to validate the syndromic score case definition and CRMS is justified.

This paper presents a novel installation protocol to build a reliable and economical line monitoring system on high voltage power lines. The proposed method is able to iteratively determine the required number of sensors and their installation location for a predefined level of risk. First, it requires a general analysis of the transmission line, which ends with a critical span analysis. Then the risk arising from the variability of weather parameters along the transmission line must be determined. Finally, it is necessary to consider what kind of problem the thermal overheating can cause at the conductor (sagging, annealing) and which additional stages can be used to reduce the risk factor to the permissible level. A case study was investigated with the data of a Central-European high voltage power line to present how the proposed method works. The results showed that there are power lines on which only distributed sensor installation concepts result in a safe and economical solution. Applying the proposed method, a comprehensive and robust sensor system can be implemented, which can be a solid basis for any dynamic line rating (DLR) system.

Climate change and agriculture interact with each other in many ways and have a complex impact. The agriculture sector needs to be prepared to adapt to the expected effects of climate change, and emphasis must be placed on prevention to achieve emission reduction targets. The research explores the current situation in the agricultural sector, the risks of climate change, as well as the Climate-Smart Agriculture (CSA) solutions that appear at Hungarian agribusiness. Examining the climate innovation activities of farms shows a coherence of the practical application. The research is based on a questionnaire survey of Hungarian agribusiness and the country directorates of the National Chamber of Agriculture. The investigation confirmed that although farmers are susceptible to Agri-Innovation, they only partly exploit the potential of digitalization. For agriculture, the spread of agricultural digitalization and technology transfer is an excellent opportunity to increase agricultural production, maintain and improve its market position, and increase its digital maturity, which can also enhance the integration of climate innovation and sustainability aspects supporting the green economic development.

The purpose of this paper is to show a new calculation model, which is able to calculate the incident energy in any places near an electric arc in case of high voltage, without neglecting ...

There are existing techniques for building; lightning protection for tall buildings, however, the design of an effective system requires a different approach from the typical one developed...

Exceeding the electric field&rsquo, s limit value is not allowed in the vicinity of high-voltage power lines because of both legal and safety aspects. The design parameters of the line must be chosen so that such cases do not occur. However, analysis of several operating power lines in Europe found that the electric field strength in many cases exceeds the legally prescribed limit for the general public. To illustrate this issue and its importance, field measurement and finite element simulation results of the low-frequency electric field are presented for an active 400 kV power line. The purpose of this paper is to offer a new, economical expert system based on dynamic line rating (DLR) that utilizes the potential of real-time power line monitoring methods. The article describes the expert system&rsquo, s strengths and benefits from both technical and financial points of view, highlighting DLR&rsquo, s potential for application. With our proposed expert system, it is possible to increase a power line&rsquo, s safety and security by ensuring that the electric field does not exceed its limit value. In this way, the authors demonstrate that DLR has other potential applications in addition to its capacity-increasing effect in the high voltage grid.

The changes in the way how electricity distribution networks are operated have major consequences on the operation of physical equipment. There is a definite need to increase the intermittent current carrying capacity of assets, while at the same time the aging distribution network consists of high percentage of devices with increased level of degradation. The article describes a possible methodology to link known degradation models and thermal limits, giving operators the possibility to extend maximal load on transformers and cables, while observing physical limits of immediate damage. The article takes into consideration the changes of the limits with degradation. This viewpoint enables the intermittent uprating of the equipment, however, does not consider accelerated aging.

The goal of this paper is to present the time and frequency domain behavior of the emitted electromagnetic signals of the three main types of partial discharges (corona, void and surface discharges) in the VHF and partially the UHF range, and to find the characteristic properties of these signals. A noise and interference free environment was used to measure the undistorted emitted signals of the discharge sources. The individual discharge pulses were investigated in both time and frequency domain, followed by the phase resolved investigation of their time domain behavior. A part of these results showed similarities, making it easier to use these properties for creating a universal digital filtering module. The other part of the results showed significant characteristic differences that were in-line with the traditional measurement results of the literature and can be used for signal separation. The results of this paper can be utilized in the development of the signal processing module of an on-site, real-time partial discharge location approximation system.

In the last decade, dynamic line rating (DLR) as a novel and cost-effective transfer capacity calculation method has been getting into the scope of transmission system operators (TSOs). By applying DLR method, it is possible to increase the ampacity of the overhead lines (OHLs) averagely in 95% of the time based on the monitoring of the actual weather conditions in the vicinity of the conductors. On the other hand, one important pillar during the application of this method - from the aspect of the TSOs - is the day-ahead transfer capacity prediction for the determination of generation schedules, which requires accurate weather forecast. By using accurate weather parameters as an input of DLR models, there is no sag violation at the maximum allowable conductor temperature. Otherwise, getting precise weather forecast is almost impossible; this affects the sag and, in this way, the whole DLR method. The aim of this article is to present how sag and clearance of the OHL spans change due to weather forecast uncertainties. For the simulations, field data from an OHL equipped with line monitoring sensors and weather stations are applied. Sag-clearance monitoring is also an important aspect in case of DLR applications regarding to the electric and magnetic field strength and distribution. Because of the potential threat for general public and occupational personnel, monitoring of sag increment might be an important aspect in the state of the art DLR related researches.

FLEXITRANTORE as a HORIZON 2020 project aims to develop an integrated platform for the next generation flexible electricity transmission system. During the project the investigation and implementation of state-of-the-art technologies will be realized, like storage systems, new market designs and business models, Dynamic Line Rating (DLR) technology or de-icing methodologies. The objective of FLEXITRANTORE’s WP7 work package is to develop a DLR based anti-icing technology for transmission lines, therefore make the grid more reliable [1].

In the risk calculation connected to lightning protection, it is important to determine the expected average annual number of accidents caused by a lightning strike. There are different methods for that (the most popular ones are the Probability Modulated Attraction Space (PMAS) theory and the Dynamic Electro-Geometric Model (DEGM)). The paper aims to represent the correct use of the mesh method (regarding different articles and methods) in lightning protection compared to the results of the rolling sphere method. For an air-termination system, it is necessary to know not only the number of the possible lightning overall but to estimate the shielding failures as well. If there is much simplification, or some parameters or environmental factors will be inadequately neglected, that could cause incorrect risk determination.

High voltage live-line maintenance (LLM) is a commonly applied method worldwide to execute planned works in the grid economically [1] . In case of bare-hand technique workers wear a so-called conductive clothing acting as a Faraday-cage which protects them against the high electric fields during the work.

Shielding properties of conductive protective suits were tested by currents and power frequency electric field strengths for different exposure conditions. The differences between torso and head shielding factors, as well as shielding factors with and without face screen were determined. Near wire and in air capacity exposure test setups were the most valid for head shielding factor assessment.

The personal protective equipment (conductive suit) should decrease the power frequency electric field high levels up to occupational permissible limit values for human safety. The personal protective equipment screening property realized by conductive materials which has shielding coefficient. It is relevant for practice to develop test method of conductive suit and materials protection properties by direct power frequency electric field measurement. The paper presents the comparison of results shielding materials testing by different methods. There were compared data of direct power frequency electric field measurement and standard test method according to IEC 60895. The suggested shielding efficiency test method was based on electric field strength measurements inside the metal holder covered by materials test sample placed in high level power frequency electric field. 14 test samples of protective suit textile with use two methods was compared. The results obtained by both methods were analyzed by means of linear approximation function as a correlation between suggested and standard test methods. This function defined minimal shielding efficiency requirements for conductive material of power frequency electric field personal protective equipment measured by suggested method. In prospect, the new method will allow conductive suits manufacturers to predict maximum possible power frequency electric field decrease for compliance with permissible limit values at workplaces. Therefore, the suggested method of shielding efficiency assessment is nearest to standardization in hygienic practice and control at workplaces parameter.

To determine the expected number of accidents caused by a lightning strike has different methods (most popular is PMAS, EGM or SLIM). The aim of the paper to present the case of the further-delvelope of PMAS method throw interesting special case.For an air-termination system it is necessary to know the number of the possible lightning strikes for a given area in a given year to design it well. If the methods, which serve that purpose to determinate the risk level, use too much simplification or will be inadequately neglected that could be cause incorrect risk determination.The aim of this paper is to show one possible case when this could happen.

Due to the increasing energy demand, new questions raise for engineers such as how to achieve high utilization of the existing transmission system. For this purpose, the investigation of network equipment and elements is indispensable. Dynamic line rating (DLR) is a cost-efficient way to raise the transmission power capacity of the existing high voltage overhead lines. DLR technology is based on the real-time thermal equilibrium of the conductors, which is the basis of the ampacity calculation of the given line. Therefore, the investigation of the thermal behavior of wires is essential to fine tune the existing calculation methodologies. The aim of this paper is to present the research regarding to the thermal behavior of high voltage conductors performed in the High Voltage Laboratory of Budapest University of Technology and Economics. In this research the time constant of a wire was determined both in case of different static and dynamic thermal processes, thus the heating and cooling mechanism of the conductor can be described in a more precise way in case of thermal monitoring of the wires.

The key issues during the operation of transmission system is the integration of renewable energy sources, the increasing demand for energy and the spreading of distributed energy generation. The transmission capacity of the overhead lines should be increased to satisfy the above-mentioned questions, while the high level of operation safety is also should be provided. Dynamic Line Rating (DLR) calculation methodology offers a cost-effective way to determine the ampacity of overhead lines in real-time. This method not only increases the transmission capacity of the line, but also improves the operational safety with the forecast of thermal overloads, which means a more resilient and flexible grid against the conventional static approach. International DLR models have some neglections while the implementation of these systems for practical application is also in initial phase. The aim of this paper to investigate the practical application of DLR system with the extension and fine-tune of existing physical models. Furthermore, the advantages of the extended physical model are also demonstrated through case studies.

Nowadays in the electricity system several challenges have been appeared that system operators have to cope with. One of the major challenges is to increase the transmission capacity of the overhead lines (OHL), while maintaining the safety and security level of the network. Dynamic Line Rating (DLR) by monitoring the real-time environmental parameters next to the conductor is a promising and cost-effective way to use the existing infrastructure with higher efficiency. There are several different deterministic DLR models in the international literature, but there are also other approaches based on soft computing or Monte Carlo simulations for the calculation of transmission capacity. The aim of this paper is to demonstrate the operation of the different models by presenting a real case study.

The transmission and distribution network play a central role in the electricity system. According to this, their operational safety and reliability are highly important due to the continuous availability of electrical energy. Live Working (hereinafter referred to as LW) is a group of activities where line workers work on energized network elements, reducing the number of blackouts and interrupts on the network. However, in the last few years the electricity system has changed, so that new challenges have been appeared for system operators. One of the main goals is to increase the flexibility of the transmission and distribution network while maintaining the reliability level. As a result, new methods such as Dynamic Line Rating (hereinafter referred to as DLR) are being introduced to increase the capacity of transmission lines. In addition to the emergence of new methods, existing technologies also need to be reviewed. The main aim of this article is to present how live line maintenance (LLM) equipment test and technology education were revised, and how DLR method could improve the reliability of the distribution network.

High voltage live-line maintenance (LLM) became a decisive working method in Hungary in the 1960s. Most of the LLM techniques and equipment - which are still in operation nowadays - were developed by Dr. Bela Csikos, who was one of the pioneers of high voltage live-line work. In those days the live maintainability of the power lines was a significant aspect during the design of towers and insulator strings. Contrarily, structures change year-by-year, especially regarding the insulators. Therefore, live working methods also shall be developed. Nowadays, new types of tower structures and insulator strings are used with reduced distances, which also means reduced clearance between the different potentials in the arrangement. During barehand live working method, the lineman has to keep the adequate distances from different potentials of power lines. Moreover, there is no uniform standard and international practice for the regulation of safety clearances. New type of mounting chair made of non-conductive material is suitable for approaching the insulator strings and their fittings safely, as the air gap between the conductive parts does not shorten. The aim of this paper is to investigate the usability of non-conductive mounting chair and the regulation of phase-to-ground clearances during insulator replacement technology, in case of several tower types and insulator types used in the Hungarian transmission grid. Another purpose of this article is to examine the possibility of reducing minimal approach distances, such as by the application of portable protective air gap (PPAG).

Due to the growing demand for electrical energy, the use of alternative transfer capacity-enhancing methods such as Dynamic Line Rating (DLR) become more and more significant. However, there are some challenges regarding the prediction of the DLR value, which are still unresolved. In the last few years several DLR pilot projects have been constituted resulting a big database of the measured environmental and load parameters. One aim of this article is to introduce how different Monte Carlo methods could be applied in probability-based DLR models to predict the DLR value and the operational safety risk factor. Based on simulations, it is possible to implement a smart DLR system in the future, which will be able to set the model parameters from time to time using big data. In order to demonstrate the advantages, relevance and limitations of the Monte Carlo simulations, a case study is presented for a genuine transmission line.

The evolution of the digital transformation presents new challenges and many new opportunities, and provides unique solutions to individual issues, both for sectors and regions. The challenges posed by the digital world have a significant impact on social and economic processes, as well as our environment. This paper aims to provide an indicator-based understanding of the main characteristics of digitalization promoting sustainable development in the member countries of the Visegrad Cooperation. The main goal of this research is to study the relationship between digitalization transformation and sustainability together. One of the basic indicators of the article is the Digital Economy and Society Index (DESI). We examined interconnections between the dimensions of the DESI index and the indicators of the Sustainable Development Goal (SDG) targets together in the V4, presented the change, evaluated the selected countries based on these aspects, and set up their ranking. Competitiveness performance data shed light on the situation in Hungary within the V4 countries, pointing out the strengths and shortcomings. The results show the extent of digital performance in each country and the relationship between their digital performance and sustainability indicators.

The lightning protection of different components of flexible systems are more and more important because the produced energy quotient increases by the time. Proportionally, the risk and the number of the lightning strikes and the probability of the fault are increasing, too. Nowadays the renewable power plants take a determinative part in the energy sector and therefore, it is necessary to calculate with the loss after a lightning strike or because other overvoltage caused fault.