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Wearing personal safety protective equipment (PSPE) plays a key role in reducing electrical injuries to electrical workers. However, substation employees often ignore this regulation due to lack of safety awareness and discomfortable feeling of wearing PSPE. Therefore, it is necessary to develop a detection algorithm for PSPE and workers to build real-time video surveillance systems in power substations. In this paper, a wear-enhanced YOLOv3 method for real-time detection of PSPE and substation workers is proposed. The gamma correction is first applied as the preprocessing method to highlight the details of the operators and data augmentation is performed. Next, K-means++ algorithm replaces K-means in wear-enhanced YOLOv3 method to derive the most suitable prior bounding box size and lift the detection speed. Then, the proposed method can be quickly and effectively trained based on transfer learning. Finally, extensive experiments are carried out on a dataset of images about usage of safety helmets, insulating gloves and boots. Using the proposed method, the mean average precision is improved by over 2% and the frames per second is the highest compared with other typical object detection methods, which illustrates the effectiveness of the wear-enhanced YOLOv3 method for PSPE and workers detection.

The IEC 61850 standard has contributed significantly to the substation management and automation process by incorporating the advantages of communications networks into the operation of power substations. However, this modernization process also involves new challenges in other areas. For example, in the field ofsecurity, several academic works have shown that the same attacks used in computer networks (DoS, Sniffing, Tampering, Spoffing among others), can also compromise the operation of a substation. This article evaluates the applicability of hierarchical clustering algorithms and statistical type descriptors (averages), in the identification of anomalous patterns of traffic in communication networks for power substations based on the IEC 61850 standard. The results obtained show that, using a hierarchical algorithm with Euclidean distance proximity criterion and simple link grouping method, a correct classification is achieved in the following operation scenarios: 1) Normal traffic, 2) IED disconnection, 3) Network discovery attack, 4) DoS attack, 5) IED spoofing attack and 6) Failure on the high voltage line. In addition, the descriptors used for the classification proved equally effective with other unsupervised clustering techniques such as K-means (partitional-type clustering), or LAMDA (diffuse-type clustering). El estándar IEC 61850 ha contribuido notablemente con el proceso de gestión y automatización de las subestaciones, al incorporar las ventajas de las redes de comunicaciones en la operación de las subestaciones de energía. Sin embargo, este proceso de modernización también involucra nuevos desafíos en otros campos. Por ejemplo, en el área de la seguridad, diversos trabajos académicos han puesto en evidencia que la operación de una subestación también puede ser comprometida por los mismos ataques utilizados en las redes de cómputo (DoS, Sniffing, Tampering, Spoffing entre otros). Este artículo evalúa la aplicabilidad de los algoritmos de agrupamiento no supervisado de tipo jerárquico y el uso de descriptores de tipo estadístico (promedios), en la identificación de patrones de tráfico anómalo en redes de comunicación para subestaciones eléctricas basadas en el estándar IEC 61850. Los resultados obtenidos demuestran que, utilizando un algoritmo jerárquico con criterio de proximidad distancia Euclidiana y método de agrupación vínculo simple, se logra una correcta clasificación de los siguientes escenarios de operación: 1) Tráfico normal, 2) Desconexión de dispositivo IED, 3) Ataque de descubrimiento de red, 4) Ataque de denegación de servicio, 5) Ataque de suplantación de IED y 6) Falló en la línea de alta tensión. Además, los descriptores utilizados para la clasificación demostraron ser robustos al lograrse idénticos resultados con otras técnicas de agrupamiento no supervisado de tipo particional como K-medias o de tipo difuso como LAMDA (Learning Algorithm Multivariable and Data Analysis).

This paper introduces the concept of a battery energy storage system as an emergency power supply for a separated power network, with the possibility of island operation for a power substation with one-side supply. This system, with an appropriately sized energy storage capacity, allows improvement in the continuity of the power supply and increases the reliability of the separated network at a specified time during the limitation of power transmission as a result of damage or disconnection of the main power line. This paper presents and describes a specific method of energy storage system dimensioning based on real measurement data. Based on the obtained parameters, an analysis of the reliability improvement of the considered network was performed. The implementation of the battery energy storage system will contribute to a more than 5-fold reduction in the occurrence of power outages in the time interval from 3 min to 1.5 h, which will clearly reduce the System Average Interruption Frequency Index and System Average Interruption Duration Index factors. In this paper, the network conditions for operational normality and failure are presented and the cost for implementation of an energy storage system (about EUR 1 million) is compared with the possible implementation of an additional power line (about EUR 5 million) to a specific power substation.

Transformers are most needful equipment in any power substation. Power supply at different voltage levels is acquired through transformer only, which gives great ease to power networks. The life of transformer can be calculated with the help of insulating parameters like oil, paper insulation, etc. In this paper, various assessment techniques are studied to explain the characteristic of transformer insulation system. These techniques deals with different parameters related to oil and paper insulation system. Characteristics of these parameters determine the degradation and aging aspect of insulation system and hence life of any transformer. Here, five aged transformer oil samples were tested at different substation locations of Himachal Pradesh State Electricity Board of rating range 16–20 MVA. Efforts are made to establish a co-relation between these different parameters and find out the condition of transformer insulation.

Power substations have accumulated a large number of knowledge texts in various forms. Named Entity Recognition (NER) of power substation knowledge can identify entities from these texts and lays the foundation for the subsequent knowledge management. To realize the entity recognition of power substation knowledge more efficiently, an improved Transformer- BiLSTM-CRF model is proposed. The model consists of embedding layers, improved Transformer module and BiLSTM-CRF module. The proposed model is compared with LSTM, BiLSTM, CRF, Transformer and their combined models in the dataset provided by power enterprises. The result on the test dataset shows that the precision is 84.8%, the recall is 85.8%, and the F1-score is 0.853, which are all better than the comnarative models.

This paper presents an upgrade of an existing fuzzy logic method for evaluation of the reliability of power substations with implemented distributed generation, considering uncertainty and imprecision of the input data. The method is presented on a 110/35 kV/kV substation and gives satisfactory results from an engineering point of view and provides a high level of precision and model simplicity.

With the world facing the urgency of energy transition, the development of efficient and quiet electrical infrastructures is of topical importance in the construction of the environment of the future. The problem of noise from power distribution systems is often underestimated, although several works in the literature underline the effect of disturbance on the population, especially concerning the low frequency range. This paper overviews the issue of the low-frequency noise generated by electrical substations, from the experimental characterization of the source to the possible mitigation measures at the source, along the propagation path and at the receiver. Alongside the general presentation, a case study serves as a practical demonstration of the proposed methodological approach. It was found that in the investigated situation the main disturbance comes from the transformer at two low-frequency harmonics of twice the networking frequency. A traditional noise barrier is designed taking into account the strict size constraints imposed by technical compatibility with the electrical infrastructure, which limits its efficacy at low frequency. Noise masking with broadband signals can be a complementary solution to further reduce noise disturbance and contain it within prescribed limits. The evaluation of subjective response of the receivers to different mitigation solutions is made possible by the availability of the impulse response.

The power systems have a history of more than 100 years. Through the years, the experience gained through the design and operation of power substations have been adapted and implemented in international standards and national regulations. The power substation design considers, simplifying, technical and safety aspects. The technical aspects address the system functional reliability, such as insulation clearances. The safety aspects consider the personnel safety during the substation operation, such as electrical safety distances in air. This paper focuses on the safety aspects not the technical. Certain safety aspects which has been considered safe during the years might be revised given the increase of the system voltages and evidence obtained during the last half century. Specifically, the distances to a live part and the vicinity zone, defined in the standards, may be revised to ensure safety during the operation and maintenance of power substations. Evidence is shown that at higher the system voltage, personnel can be strike in the event of a breakdown using the present approach. Thus, this paper addresses electrical safety distances in air as given in some power substation standards with the aim to highlight discuss the relation between the insulation design and the criteria of electrical safety. Evidence, from laboratory tests, show that the breakdown phenomena, at higher voltages, challenges today’s definition of electrical safety distances in air. For this reason, a contribution is done to obtain electrical safety distances in air to ensure that the risk of personnel of being strike, in the event of a breakdown, when working in power substations, is not higher than the risk of today’s modern life.

A power substation is susceptible to intrusions of foreign objects. The intrusions can likely result in failures of power supplies. Therefore, recognizing foreign objects becomes important to ensure constant and stable power supplies. However, existing object recognition methods fail to achieve acceptable accuracy and performance. In this paper, we propose an efficient Foreign Objects Detection Network for Power Substation (FODN4PS) to improve the recognition accuracy with less time. FODN4PS consists of a Moving Object Region Extraction Network (MORE Net) and a classification network, where the MORE Net can get the position of foreign objects, and the classification network can recognize the category of foreign objects. Experimental results show that FODN4PS is faster and more accurate in object recognition than the Fast R-CNN and Mask R-CNN.

Most often, electrical consumers in the residential and educational sectors are different from industrial electrical consumers. Whereas the vast majority of industrial electrical consumers are low-voltage, three-phase (with three or four wires), electrical consumers in the residential and educational sectors are low-voltage, single-phase. However, in practice, electrical consumers in the residential and educational sectors are in large numbers. Usually, current and voltage unbalances are lower in the industrial sector compared to the residential and educational sectors, where there are a large number of low-voltage, single-phase consumers that are connected/disconnected in an uncontrollable way and that need to be wired and balanced on each phase of power transformers from power substations. The purpose of this paper is to present the results of electrical balance and improve the power factor in the power substation from residential and educational sectors. The paper investigates the current and voltage unbalance of nonlinear con sumers in the residential and educational sectors. For this purpose, we performed measurements in the laboratory and the power substation to investigate the unbalance in the three-phase system. Laboratory measurements were made in the unbalanced operation of the single-phase electrical consumers connected at three-phase system. The measurements from power substation were carried out after the electrical consumers were uniformly spread among the three phases from the low-voltage power network, on two different days: a workday and a weekend day. The current and apparent power unbalance were reduced and the power factor was improved using the capacitive single-phase electric consumers (e.g., personal computers, which are in large numbers in such sectors) evenly across the phases.

Monitoring of electromagnetic field (EMF) has been widely demanded, particularly in vicinity of well-known EMF sources, such as high-power substations. Regarding the fact that modern power substations are equipped with different communication equipment for remote control and supervision of its processes, they become an additional, important source of the high-frequency electric field. Thus, this paper considered the high-power 110/x kV outdoor substation “Novi Sad 7”, once more, performing periodic EMF monitoring and presenting newest measurement results of the high-frequency electric field in its vicinity. The latest measurement results are compared with results obtained in previous 2015 measurement campaign. Regarding the acquired measurement results in 2018, as well as in 2015, they are below the Serbian prescribed reference levels, while subsequent EMF exposure is also far below the maximum allowed level.

Recently infrared cameras have been widely used to diagnosis degradation status of the power substitution system. At the place of high magnetic field, however, electronic parts of infrared camera take a place problem that is not reasonable working due to high magnetic field. In this paper, technique of design for reflector is proposed to perform degradation diagnosis without damage of infrared camera in a power substation system including the rectifier that is able to impact to the infrared camera by high magnetic field.

The high-power substations, as an essential part of power distribution network, are being equipped with various communication equipments for remote control and processes supervision. Therefore, those objects become sources of the high-frequency electromagnetic field (EMF). Moreover, regarding its infrastructure and constant security observation, those objects become highly interesting for operators of commercial communication services. These facts are in line with public demand for EMF investigation in the vicinity of such objects, but not only of the low-frequency magnetic field. In this paper, the case study of the high power 110/x kV outdoor substation “Novi Sad 7” has been considered, presenting the high-frequency electric field strength monitoring in its vicinity. The obtained measurement results are below the Serbian prescribed reference levels, while potential EMF exposure is far below of the maximal allowed level.

The article presents the idea of using expert evaluation methods for choosing power substations equipment. The article suggests using analytic hierarchy process as the most convenient for such type of complex task solving. Direct analytic hierarchy process is represented as an improvement over the traditional method developed by Thomas L. Saaty. It simplifies analytic hierarchy process by getting weights of the criteria and alternatives without pair-comparison matrix forming.

The nonintrusive load monitoring is an emerging technology which aims to control energy consumption and the analysis of electrical equipment behavior from power substation internal services equipment. The paper describes a calculus method and a system for nonintrusive load monitoring of the electrical parameters from the auxiliary services on a power substation.

The most known sources of the low-frequency electromagnetic field (EMF) can be found in electric power systems. Those systems and their power distribution parts have become the backbone of economic, technological and overall development of human society, intensely in modern-days. The actual humanity highly depends on the reliable power supply and thus a number of power distribution substations have been established, even in densely populated residential parts of the cities. The presence of such a power substation increases the public concerns on dangerous health effects, considering the exposure to EMF in the vicinity of substations. Thus, the comprehensive and detailed monitoring was demanded, along with the exposure assessment to EMF radiation. The continuous broadband monitoring method of the Serbian Electromagnetic Field Monitoring Network - SEMONT has been considered in this paper, in a case study of the power substation “NS7 - South Telep”, located in the city of Novi Sad, the Republic of Serbia. The exposure assessment, based on daily boundaries, has been employed, showing that acquired results emerge to be far below the Serbian prescribed reference levels.

The intensive increase of the number of population in modern cities demands a highly reliable power supply, requiring power distribution systems that will accomplish this challenging task. In order to increase the reliability of consumers supply, the additional power distribution substations are commonly installed, which in time become surrounded by the expanded residential areas. In consequence, their presence increases the health concern of residents, having in mind that power substations are known sources of the low-frequency electromagnetic field (EMF). Therefore, the continuous monitoring of EMF is expected, as well as the adequate assessment of corresponding exposure of population in vicinity of such objects. In this paper, the test utilization of a modern, wireless sensors-based monitoring network, the Serbian Electromagnetic Field Monitoring Network - SEMONT, was considered for the advanced low-frequency EMF monitoring in the upcoming smart cities environment. The case study and test measurements were performed in vicinity of the power substation “NS7 - South Telep”, located in the city of Novi Sad, the Republic of Serbia, where the acquired results emerge to be far below the Serbian prescribed reference levels.

Northrop Grumman Corporation has been developing 10 kV SiC MOSFETs and Junction Barrier Schottky diodes for application to a 13.8 kV 2.7 MVA solid-state power substation. The design of half-bridge power modules has extensively used simulation, from electron-level device simulations to the system-level trade studies, to develop the most efficient module for use in the SSPS.

While continuity based testing is a relatively well accepted method for assessing the integrity of a grounding grid, no specific continuity based test has distinguished itself with practitioners at large. Why this continues to be the case is not completely understood but it is likely a combination of ignorance of more effective procedures and the availability of better instrumentation. This paper reviews the various continuity based methods used for integrity testing and the characteristics required of a test procedure to make it effective at assessing integrity. This is considered primarily due to a lack of review of the various methods and instrumentation available to perform integrity testing. Accurate measurement of resistance in the electrically noisy environment of a power substation is a difficult task. In the case of grounding grid measurements, not only are the noise levels quite high but the resistances to be measured are relatively small, and the absolute significance of a specific measurement can be obscure. In practice the context of any given measurement is crucial to determining the significance of the measurement. While continuity testing can be performed at any power installation this paper concentrates specifically on the integrity assessment of a major substation. Most power utility substations are of a reasonable size, typically a few thousand square meters of real estate, which usually defines the extent of the grounding system and hence the extent of the integrity testing. This paper identifies the obstacles to performing an accurate measurement of resistance in the noisy environment of a power substation, establishing measurement targets and specific instances of poor integrity.

The paper represents results of an investigation of distribution of the magnetic field intensity near the equipment of the 500 kV power substations in Russian Federation. The investigation is conducted with position of security life activity of the technical personnel.

KEYWORD:HTS; Cryogenic; Forced circulation; Heat loss; HTS substation; HTS apparatus; Cool- ing system ABSTRACT:A 10 kV High Temperature Superconducting power substation with a cooling system was developed and has been put into operation in power distribution system for more than three years. The working conditions, heat resource and the distribution character of the four apparatuses working at the 10 kV/630 kVA HTS substation were analyzed. The heat load is distributed along the length for the cable for which thus a forced enclosed circulation system is necessary; while it is con- centrated within only several cryostats for the other three HTS apparatus for which it is enough to cool only with an opened loop cooling system by consuming of liquid nitrogen. And an independent cooling system with refrigerator for the 1 MJ SMES is a good selection due to the different working temperature range. Based on the analysis and discussion, a concentrated evaporative cooling station which includes an opened loop cooling system without circulation and a forced circulation system with a closed circle was designed and constructed.

This paper describes software realization and implementation for the communication according to the IEC61850 Standard, between the module for supervising teleprotection equipments and the power substation server. Teleprotection equipment have important role in transmission of messages for power line section tripping. Software is implemented on the hardware platform type: MSC “nanoRISC-S3C2416 MB2” which belongs to the “COM - computer on module” systems.

The paper presents results of an investigation of distribution of the electric field intensity near the equipment of the 500 kV power substations in Russian Federation. The investigation is conducted with position of security life activity of the technical personnel.

Many types of regenerative braked cars are being introduced in dc electric railway for energy saving. Recently specially inverter cars are being placed in service. In East Japan Railway Company inverter control cars (type 209) have their regeneration coefficient mutch increased from about 25% to about 33% as compared with cars (type 205) with superposed field excitation control.We may expect the regenerative coefficient to be lowered by invalidation on particular sections or particular time zoon, so we must search for the dc feeding system which can level up the regenaration coefficient. On the other hand, recently thyristor rectifier substations are being built to superannuated silicon rectifier substations. We can control the feeding voltage of substation. In the case of inverter cars such as type 209 the author has studied the quantitative effect of saving enegy with many kinds of feeding voltage control system, and demonstrated with simulation the increase in regenerative power and decrease in power consumption without levellig down the acceleration ability of cars.

Summary form only given. This paper presents a conceptual approach for eliminating the multiple estimation problem of impedance-based fault location methods applied to power distribution systems, using the available measurements of current and voltage fundamentals at the power substation. Three test systems are used to identify the faulted lateral obtaining high performance, even in the case of similar feeder configurations. This approach shows that it is possible to obtain a unique fault location, eliminating the problem of multiple estimation in tree-shaped radial systems using the single-end measurements at the distribution substation. Finally, this approach also contributes to improve the power continuity indexes in distribution systems by the opportune zone fault location.

Experimental Results from Physical Model of Bidirectional Power Flow Regulator for Power Substations of Electrical TransportThis article is about model of bidirectional power flow regulator for power substations of electrical transport. The paper presents an experimental model which is made in the laboratory of Power and electrical engineering of Riga Technical University. Also principal block scheme and principal schemes of that model are presented in the form of computer modeling as well as some main results of experiments are presented in the form of diagrams.