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Data analysis has become most widespread field of research and it has extended in almost every field of study. Considering the recent trends and developments in the field of communication and information technology, there is a scope of combining the monitoring of substation equipment with big data analysis technology. That will result in an improved data analysis ability, information sharing and utilization rate of monitoring data. In the proposed work, the authors have introduced the big data analysis and its corresponding application in the monitoring of substations. Basic concepts and the procedures of the typical data analysis for general problems are also discussed. As a main part of the paper, different types of distributed data analysis techniques have been proposed, in which two relational online analysis, namely Hive and Impala and one H Base multidimensional online analysis are important. These data analysis techniques are proposed considering the analysis efficiency, storage performance from the business development requirements point of view of the substation. The result obtained depicts that the proposed model has an advantage in storage overhead and roll-up performance, when compared with the traditional method, although the data loading speed is approximately 1.7–1.9 times of the traditional model. Some experiments are carried out in order to verify the validity of the model.

To balance the potential distribution on the surface of a substation, an equal spacing arrangement of the grounding grid conductors is not an economical solution. The implementable solution is an unequal placement of its constituent elements. The design methodologies of such a configuration are complex and require computer-assisted numerical analysis. This paper proposes and validates a very simple method, based on an arithmetic progression, of arranging the conductors of the grounding grid that guarantees the reduction of touch and step voltages, ensures the efficiency of the material used and has no limitations on its applicability for atypical substation surfaces (too large or too small), respectively for few or many parallel conductors. To certify the method, the proposed algorithm is analyzed, through the CYMGRD Substation Grounding Program, and compared to the technologies currently applied, for the substation grounding grid presented as an example in the IEEE Guide for Safety in AC Substation Grounding 80™- 2013 standard.

Introduction: Recent industrial developments have led to the rapid development of electricity production successively; it leads to power grids and high voltage utilization. The effects of electromagnetic fields have been investigated on the organism by researchers. In many cases, it is not possible to conclusively comment, because of the slowness impact of fields of life-cycle processes and the long-term studies. According to the harmful effects of exposure to electromagnetic waves, this study was conducted to investigate the electric field intensity and magnetic field at high voltage substations (230 kv) in Golestan province. Materials and Methods: This Cross-sectional study (descriptive-analytical) was performed at 230 kv substations in Golestan Province (1396). The electric field and the magnetic field density were measured by instrument model TM-190 at 5 posts in Golestan province and compared with the standards. Results: 100 % of the measured electric field intensity and magnetic field of the 230 kv substations in Golestan Province is less than the standard. Conclusion: The magnitude of the electric and magnetic fields is in the occupational limits.

Guluk-Guluk is supplied by a 20 kV system from the Pamekasan GI and Sumenep GI, resulting in a voltage drop of 5 kV. The fall in the voltage on the load side cannot be overcome through the regulation of transformer tapping or the use of bank capacitors, so the possible way is to build a new GI. The construction of GI Guluk-Guluk requires a new transmission line. A good electric power transmission has a low voltage drop, high efficiency and high surge impedance loading (SIL) values. Efforts to improve the voltage by changing the tapping in the power transformer located at the nearest substation only produce a voltage of 166.07 kV. The provision of bank capacitors in Guluk-Guluk produces a voltage of 17,542 kV. The construction of GI Guluk-Guluk requires a new transmission line that connects Pamekasan to Guluk-Guluk, Sampang to Guluk-Guluk and Guluk-Guluk to Sumenep. The construction of a 150 kV network line requires calculations to determine network configurations, conductors, isolators, tower types, and electrical equipment supporting 150 kV transmission systems such as current transformers, voltage transformers, power breakers, and arresters. In this final project, simulation is done with the help of ETAP 12.6 software. The results of calculations and simulations of the transmission line toward Guluk-Guluk give a voltage drop of 4.89 kV, with an efficiency level of 96.74% and a SIL value of 41.225 MW. so these results are sufficient to be used as a reference for GI development in Guluk-Guluk.

Due to our dependency on electricity, it is vital to keep our powersystems secure from cyber attacks. However, because power sys-tems are being digitalized and the infrastructure is growing increasingly complicated, it is difficult to gain an overview and secure the entire system. An overview of the potential security vulnerabilities can be achieved with threat modeling. The Meta AttackLanguage (MAL) is a formalism that enables the development ofthreat modeling languages that can be used to automatically generate attack graphs and conduct simulations over them. In this article we present the MAL-based language SCL-Lang which has been created based on the System description Configuration Language (SCL) as defined in the IEC 61850 standard. With SCL-Lang one can create threat models of substations based on their SCL files and automatically find information regarding potential cyber attack paths in the substation automation system configuration. This enables structured cyber security analysis for evaluating various design scenarios before implementation Part of proceedings; ISBN 9781450383196, QC 20230117

The deployment of infrastructures related to the Smart Grid concept introduces data communication networks in the grid operation systems (control, communication, and monitoring). The implementation of data communication networks facilitates and improves the efficiency of the tasks related to the generation, transmission, and distribution of electrical energy. In turn, network management is being permeated by new technologies such as Software Defined Networking (SDN) and network virtualization, that promote automation and innovation of communication networks aiming to overcome the lack of flexibility and the difficulties to evolve that are present in current communication networks. In this context, this paper proposes a reconceptualization of the power substations communications network architecture based on the IEC 61850 standard. Here, we present a complete view of the Smart Solution for Substation Networks (S3N) architecture, which allows modeling the future power substations communication networks taking advantage of the benefits introduced by SDN and virtualization technologies. In addition, in order to provide a better understanding of the challenges arising in this area, and to generate new research interest in this field, a review of several studies oriented to determine the feasibility of incorporating SDN as a key element to improve the management and operation of the power substations communication networks is presented.

The continuous development of the power systems by implementing new technologies for management and connection of new sources of electricity requires improvement of the power supply security. The present work is dedicated to analysis of the causes of power outages in the medium and high voltage power grids on the territory of the Republic of Bulgaria. The main types and places of occurring power outages in power lines, substations and power transformers have been analyzed and the causes for them are summarized. Indicators for assessment of the power outages related to power lines and substations are presented. Measures to improve the technical condition of high voltage power lines, substations and medium voltage switchgear are proposed. The power outages due to human errors of the service personnel in the power grids have been considered and measures to prevent such accidents depending on their objectivity and subjectivity are proposed.

Asset-management accounts for a significant share of grid operators&rsquo, influenceable costs, which are under high economic pressure due to deregulation. In asset-management, visual inspections are the main measure to determine asset conditions. In the context of digitalization, we propose a concept to acquire additional information about the condition of distribution substations and to derive flexible inspection intervals from this information, in contrast to fixed intervals that are common in scientific literature and practice. Thus, knowledge about the substations increases, inspection intervals can be expanded dynamically, and significant cost savings are possible, which we demonstrate by the example of a German distribution grid operator.

To aid in the integration of renewable and residual energy sources in the energy system, energy flexibility is required. By charging and discharging energy storage, energy flexibility can be created and heat demand and heat generation can be matched in time. One possible source of energy flexibility is the thermal capacity of the water in district heating network pipes. Effective use of this thermal energy storage requires efficient techniques to determine the available flexibility. The goal of this paper is to determine the required level of detail of a substation model to characterise network flexibility through simulation. The substation models differ in the assumptions that are made and range from a detailed, non-linear model to a simple, linear model. To analyse the results, we identify different phases occurring during a network flexibility activation. By determining if reduced models are as effective in reproducing important flexibility characteristics as more detailed and computationally expensive models, network flexibility characterisation can be simplified and sped up. Results show that the network flexibility can be adequately characterised even with very simple models, provided correct assumptions are made.

We herein discuss a smart district heating (DH) grid whereby smooth operation is achieved, and individual heating solutions, and passive or energy+ building-specific systems are implemented by means of flexible heat demands, thermal energy storages, and transmission resources. For future energy systems, low-temperature district heating lines combined with heat savings and reduced environmental impact represent a promising alternative to integrating fluctuating renewable sources. What makes this study relevant is scientific need of having a low-temperature distribution branch within an existing exclusively high-temperature district heating system. Non-renewable heat production is partially replaced with heat pumps and thermal energy storage facilities. Heat pumps use renewable electricity to produce completely renewable heat. Fundamental technical and consumer-oriented aspects of the power system will have to be adapted to using heat pumps and thermal energy storages. We created a large database of validated heating uptime values for specific buildings and outdoor conditions. We herein dwell upon an alternative heating design. The new concept is based on using transformation units as well as branch lines going from street mainlines to consumers’ substations, whereby a branch line consists of two single pipes, a dual pipe, or a triple pipe. Such branching creates a subnetwork with different heating parameters. The temperature for such a subnetwork is specifically optimized. Optimization relies on such as data as use of thermal energy, heat loss rates, and parental-system data. As a result, we modeled a network whose primary nodes had a low operating temperature. This reduces heat loss as well as fuel consumption while enabling less environmentally harmful heat production. Besides, such use of thermal energy combined with self-production can be important for creating renewable energy systems in the future. Therefore, future research and development shall be targeted at creating low-enthalpy facilities that use renewable energy to produce and store thermal energy as simulated when modeling such a modified subsystem (subnetwork).

Fundamental components of the distribution systems of electric energy are primary and secondary substation networks. Considering the incorporation of legacy communication infrastructure in these systems, they often have in- herent cybersecurity vulnerabilities. Moreover, traditional intrusion defence strategies for IT systems are often not applicable. With the aim to improve cybersecurity in substation networks, in this paper we present two methods for monitoring SCADA system: the first one exploiting neural networks, while the second one is based on formal methods. To evaluate the effective- ness of the proposed methods, we conducted experiments on a real test bed representing the substation domain as close to real-world as possible. From this test bed we collect data during normal operation and during situations where the system is under attack. To this end several different types of attack are conducted. The data collected is used to test two versions of the mon- itoring system: one based on machine learning with a neural network and one using a model-checking approach. Moreover, the two proposed models are tested with new data to evaluate their performance. The experiments demonstrate that both methods obtain an accuracy greater than 90%. In particular, the methodology based on formal methods achieves better per- formance if compared to the one based on neural networks.

For extended critical infrastructures such as the power grid, electromagnetic compatibility (EMC) testing of electronic components alone is not sufficient to assess the risk of electromagnetic (EM) attacks. This paper presents results on a methodology for high-power EM based risk assessment of large structures considering the example of smart grid substations. The evaluation involves control, protection, and communication equipment used in substations as part of supervisory control and data acquisition systems and ready for the smart grid. The methodology developed in this paper evaluates the threat, vulnerability, impact, and protective measures as indicators in various scenarios of both conducted and radiated intentional EM interference (IEMI) threats to these systems. In order to assess these indicators, fundamental data on available IEMI sources, generic substation layouts, and their mitigating effects, coupling paths, and IEMI susceptibilities has been gathered in several test campaigns and studies. Electrical field strengths generable by commercially available power sources inside substations have been estimated considering measured shielding characteristics of the buildings and attainable target distances. A comparison with measured susceptibilities of control equipment to IEMI reveals noticeable security issues. In particular, expected field strengths inside substation buildings can be much higher than the immunity levels for control systems as requested in EMC standards.

With the rapid development of global satellite navigation system technology, multi-mode satellite navigation positioning technology that can be compatible with multiple navigation systems at the same time is bound to become the future development trend. Compared with the single-mode navigation system, the multi-mode navigation system has many advantages, such as a large number of visible stars, a wide coverage, high positioning accuracy, and good reliability. Based on this, this paper applies Beidou and GPS dual-satellite positioning algorithms in substations and studies its key technologies. Specifically, with the aid of MATLAB to solve the Beidou double satellite positioning, GPS positioning results, and the big dipper, GPS double satellite positioning in two times, four times, eight times more weight under the condition of coordinate values and the actual coordinates on the x, y, and z axes deviation were compared. The results pointed out that GPS and Beidou double satellite single point positioning effect would be different under different weights. Therefore, in the actual positioning, the positioning effect of the algorithm can be improved by adjusting the weight. In order to test the feasibility of the proposed Beidou and GPS dual satellite positioning algorithms, positioning experiments were carried out, and the results were compared with the single satellite positioning results. The results showed that the curves of Beidou and GPS dual satellite positioning algorithms were highly fitting to the actual curves, confirming the feasibility of the proposed algorithm. This study aims to improve the accuracy and efficiency of substation positioning and navigation for the development of domestic power transformation.

A three-phase reference system for in-situ calibration of High Voltage (HV) Revenue Metering Systems in substations has been established. It consists of a high-accuracy three-phase power meter, including corresponding current and voltage transformers (CTs and VTs). The reference system is capable of performing power measurements up to 150 kV system voltage and line currents up to 5000 A. The excellent results of the calibration and further testing of power meter, CTs, and VTs indicate that an overall system uncertainty of better than 100μW/VA can be achieved., 2019 IEEE 10th International Workshop on Applied Measurements for Power Systems (AMPS), September 25-27, 2019, Aachen, Germany

With the development of a smart grid, the automatic location of power equipment is becoming a trend. In this study, a method for automatic location identification and diagnosis of external power insulation equipment based on YOLOv3 is proposed. This deep learning algorithm is used to extract the characteristics of image data under the visible light channel of the insulator. It learns and trains the collected data to realise the rapid location identification and frame selection of the external insulation equipment and extract discharge characteristics of the target box under the ultraviolet channel. According to the number of photons and the spot area information, the operating status of the equipment is determined. The results show that the YOLOv3 algorithm with a training rate of 0.005 achieved a fast convergence of the location recognition model. The average recognition accuracy was 88.7% and the average detection time was 0.0182 s. The combination of visible light path insulator target recognition and ultraviolet light path diagnosis can realise a lean and intelligent diagnosis of power equipment. This method had good real-time performance, accuracy, and robustness to the background. It provides a new concept for intelligent diagnosis and location analysis of power equipment.

The article presents the results of the development of new methods aimed at more accurate interval estimate of the experimental values of voltages on grounding devices of substations and circuits in the control cables, that occur when lightning strikes to lightning rods; the abovementioned estimate made it possible to increase the accuracy of the results of the study of lightning noise by 28 %. A more accurate value of interval estimation were achieved by developing a measurement model that takes into account, along with the measured values, different measurement errors and includes the special processing of the measurement results. As a result, the interval of finding the true value of the sought voltage is determined with an accuracy of 95 %. The methods can be applied to the IK-1 and IKP-1 measurement complexes, consisting in the aperiodic pulse generator, the generator of high-frequency pulses and selective voltmeters, respectively. To evaluate the effectiveness of the developed methods series of experimental voltage assessments of grounding devices of ten active high-voltage substation have been fulfilled in accordance with the developed methods and traditional techniques. The evaluation results confirmed the possibility of finding the true values of voltage over a wide range, that ought to be considered in the process of technical diagnostics of lightning protection of substations when the analysis of the measurement results and the development of measures to reduce the effects of lightning are being fulfilled. Also, a comparative analysis of the results of measurements made in accordance with the developed methods and traditional techniques has demonstrated that the true value of the sought voltage may exceed the measured value at an average of 28 %, that ought to be considered in the further analysis of the parameters of lightning protection at the facility and in the development of corrective actions. The developed methods have been tested in surveys of the electromagnettic environment of 27 active high voltage electric substations with a 110 kV outdoor switchgear. The application of the techniques amended the accuracy of the information collected, the correctness of the evaluation of the electromagnetic environment of high-voltage substations with a 110 kV outdoor switchgear, the effectiveness of the developed adequate measures to protect against lightning effects.

The inclusion of smart grid features such as demand response (DR) and network automation for capacity planning of substation transformers may provide substantial monetary savings. This paper proposes an optimization model for quantification of the savings in capacity management of substation transformers over long-run. The proposed model incorporates the DR as a resource to decrease the outage cost during contingencies while considering existing switching types for load transfer between substations. The model provides optimal selection and scheduling of multistage transformer installations and their refurbishments by considering all the costs associated with them including investment, losses, maintenance, reliability, and the salvage value. For a realistic study, numerical value of the savings in transformers’ cost is calculated for a typical Finnish two-transformer primary distribution substation planning over a period of forty years. Case studies are performed based on situations encountered by utilities and type of load transfer switching (manual and remote) between substations. A sensitivity analysis based on DR penetration and load curtailment (LC) cost is also performed. The results indicate that substantial monetary benefits can be obtained in substation transformers’ cost by utilities through employing DR. The benefit of DR is superior for cases where it is used in combination with remote switching of load transfer between neighbouring substations (NSS).

Renewable generation in power systems has proved to be challenging for system operators owing to the increasing levels of penetration. The operation of power systems currently requires additional flexibility and reserves due to the intermittency and unpredictability of renewable generators. However, it is difficult to precisely predict and control the stochastic nature of renewable sources, nevertheless, its capacity continues to increase. To monitor and control renewable generators efficiently, the entire system needs to be established in a hierarchical order. This study proposed the concept of a substation that is uniquely designed for renewable interconnection. The purpose of this substation is simple: to make the renewable generators dispatchable to operators such that each group of renewable generators is sufficiently stable to be considered as conventional generators. For this purpose, methods for sizing and controlling energy storage system are proposed based on forecasts and error distributions.

The management of transformers’ capacity is a vital task for planners and asset managers due to their high cost. This paper proposes an optimization model for capacity management of transformers in a substation over long-run. The model considers the present worth costs of investment, losses, maintenance, reliability, and the salvage value of transformers for providing the optimal selection and scheduling of multistage transformer installations and their refurbishments. In the optimization model, growing failure rate of transformers along with their age is incorporated and the cumulative loss-of-life (LOL) of transformers is also used in determining their salvage value. The developed model is applied for planning and management of transformer capacities for a residential load dominant two-transformer primary distribution substation over a period of 40 years. The simulations are performed for various case studies representing the situations encountered by utilities. An extensive sensitivity analysis is also conducted for several conditions of the system parameters. The numerical results indicate the worth of inclusion of variable failure rate and LOL of transformers in their capacity management.

Group substations have dominated district heating (DH) systems in China so far. In order to explore the applicability of building substations to DH systems in China, the case study has been carried out in Ulanhot, by comprehensively comparing the energy consumptions and costs of group and building substation systems. Firstly, building simulation is used to help design the substations and DH networks, and analyze the operation considering variable flow and holiday control, which revealed the energy-saving advantages and flexibility of the building substation system. Secondly, the structure of the outdoor network in the building substation system is redesigned using the results of building simulation. Then, the total energy consumption of the group and building substation systems, including heating energy, pumping energy, and heat loss, is simulated and compared, considering the regulation of the water temperature. According to the operation data of the group substation system in the last two heating periods, the relative error of the simulated total energy was −6.8%. Finally, the annual cost method is employed for the economic analysis, which shows the superiority of the building substation system with annual cost reductions ranging between 5.7 and 5.9% for a lifetime range of 10–30 years.

For the implementation of measures to maintain the quality of the energy industrial enterprises have to spend a significant material and monetary assets. In this regard, significant is the feasibility study of the allocation of such funds and, primarily, the determination of the economic damage arising from low quality of electricity. The reliability of the electricity metering system, relay protection and automation of modern digital substations depends on the quality of electrical energy. At the present time to improve the reliability of the substation operation it is necessary to monitor indicators of quality of electric energy, allowing you to take organizational and technical solutions for their improvement. Monitoring the power quality at the input traction substation has shown that indicators such as the coefficient of the n-th harmonic component of the voltage does not meet the standards GOST 13109-97. The source of higher harmonics is a voltage Converter used on the locomotive. To eliminate higher harmonics in the supply network for traction substations will need to install power filters. Today, the USB-analyzer of power quality «Digital system for the measurement of electrical energy quality» type of DSMEEQ of accuracy class 0.2. Work energy requires reliable and quality electricity supply to consumers. The new model of balancing energy market are bilateral contracts. The main task of this market, it ensure the stable and reliable operation of the unified energy system of Ukraine, that is, transmission and supply of electricity of appropriate quality., Надежность работы системы учета электроэнергии, релейной защиты и автоматики на современных цифровых подстанциях зависит от качества электрической энергии. В настоящее время для повышения надежности работы подстанции необходимо контролировать показатели качества электрической энергии, что позволяет принимать организационные и технические решения по его повышению.

The advanced traction power supply system (ATPSS) is a new directional development for traction power supply systems, which can totally remove the neutral sections and effectively promote power quality. However, the existing converters suffer from small substation capacity. In this paper, a new configuration based on a three-level neutral point clamped (3L-NPC) three-phase to single-phase cascade converter in a substation is proposed for ATPSS, which can be used to match the capacity of the converter for high voltage and large power applications. The control strategy of the proposed converter is analyzed in depth, and the phase disposition sinusoidal pulse width modulation (PD-SPWM) with phase shift carrier SPWM (PSC-SPWM) is employed in the inverters. Then, the inductance equalizing circuit is applied for the voltage balance on the DC-link. Besides, a LC filter circuit is designed to eliminate the double line-frequency ripple of DC voltage. Afterwards, a simulation model and an experimental prototype are developed, respectively. The simulation results show that the proposed converter in this paper can not only meet the requirements of voltage and capacity for the traction network, but also improve power quality. Finally, the experimental results verify the correctness and feasibility of the proposed control strategy.

Purpose. Definition of the direction for further research to improve accuracy of the calculation of rated parameters of ground grids based on the analysis of statistical databases of electro-physical characteristics of the soil. Methodology. To solve this problem we compiled the statistical base of soil of Ukraine in the location of electrical substation, we performed the statistical analysis for the number of layers of geoelectric structure, and electrical characteristics. In the experiments implemented the comparing of accuracy calculation of the most typical three-layer soil in the Ukraine, by the new three-layer model of ground grids and the equivalent two-layer model, which used previously. Results. On the results of analysis the ranges of the electrical resistivity and statistical distribution for electro-physical characteristics of the soil are determined. The resulting distributions allow to develop criteria for instruments, installations and means of interpretation during the sounding of soil, as well as the requirements for mathematical models of ground grids. It was found that the most typical for places of locations the electrical substations in Ukraine are three-layer geoelectric structures. In the paper the statistical distribution for three-layer soil by type (Q, K, H, A) are described. The results of numerical experiments show that the use of methods to simplify of the multilayers soil does not allow the calculation of grounding grids with high accuracy. In the work recommendations for applicability the method equivalenting depending on the type of geoelectric structure are developed. Originality. For the first time, we obtained the statistical distribution of stratification of the soil in the location of power plant in Ukraine, determined the accuracy of the method to simplify a multi-layer soil in determining the rated parameters of grounding grids. In the paper the necessity to develop a mathematical model of the grounding device located in the three-layer soil is shown, as well as a new installation of soil sounding, which allows to increase the depth of sounding and new means of interpreting the results of sounding Wenner installing a four-layers geoelectric structure. Practical value The resulting recommendations for the applicability of equivalenting of multilayer soil, as well as research in specific work areas would help to reduce costs on materials and labours during the modernization and upgrade of grounding devices, moreover it will increase the electrical safety and reliable operation of electrical substation., На основании анализа результатов зондирования получено статистическое распределение слоистости грунтов в местах расположения энергообъектов Украины, разработаны рекомендации о применимости метода эквивалентирования многослойных геоэлектрических структур при определении нормируемых параметров заземляющих устройств. Доказана необходимость создания математической модели заземляющего устройства, расположенного в трехслойном грунте, а также новой установки для зондирования грунта, позволяющей увеличить глубину зондирования, и средств интерпретации., На основі аналізу результатів зондування отримано статистичний розподіл кількості шарів ґрунту в місцях розташування енергооб’єктів України, розроблено рекомендації щодо застосування метода еквівалентування багатошарових геоелектричних структур при визначені нормованих параметрів заземлювальних пристроїв. Доведена необхідність створення математичної моделі заземлювального пристрою, розташованого в трьохшаровому ґрунті, а також нової установки для зондування ґрунту, котра дозволить збільшити глибину зондування, та засобів інтерпретації.

Introduction. Earthing device electrical substation in modern conditions must meet both the requirements of electrical safety of people and animals, as well as electromagnetic compatibility requirements established her electrical equipment. These requirements are intended to address issues of protection against surges and interference caused by lightning impulse currents and switching. Aim. To investigate the distribution of single-phase short-circuit current in the substation grounding devices. Task. On the basis of the proposed design scheme of substitution substation grounding device, consisting of a substation earthing system and «cable-supported» an algorithm for calculating the resistance of the grounding device substation and distribution of single-phase short-circuit current on the circuit elements. Method. Mathematical modeling and calculation engine. Results. On the basis of calculations and studies analyzed the current distribution of single-phase short-circuit between the substation earthing system and earthing «rope-reliance». Studies carried out for the actual range of variation of the circuit parameters, showed that the earthing resistance substation substantially affects the current distribution in the one-phase short circuit fault. For example, using the graph shows that with increasing resistance grounding system of "rope-supported" the proportion of single-phase short-circuit current flowing from the substation earthing increases, while the proportion of single-phase short-circuit current flowing from the grounding device supports decreases and vice versa. In addition, when rationing grounding systems at substations for the touch voltage is necessary to analyze all the possible modes of operation of the network, which is substationed. Conclusion. The results obtained are recommended to take into account in the design of grounding systems at substations.

Asset management and optimization is becoming increasingly adaptable for distribution utilities with the help of developments in the digital and wireless technology. Medium voltage cables, cable accessories (joints and terminations) and distribution transformers are most prone to the insulation defects. This paper presents an online partial discharge (PD) diagnostic system to detect and locate the weak insulation spots developed in the network components spread over the distribution area. The PD pulses originating and propagating from the defect site arrive at feeder joints, terminals and T-splices and are reflected from there. This makes the interpretation of the measured signals ambiguous in order to find the location of PD faults, while using conventional location techniques. An improved technique is introduced to monitor multi-section multi-branched cable network. Identification of the faulty location is carried out by using direction of arrival (DOA) of PD signals. The DOA of PD signals is obtained by using directionally calibrated Rogowski coil induction sensors. Polarity of captured PD signals with reference to supply voltage, determines their DOA. Rogowski coil along with its directional sensing feature is simulated in ATP-EMTP. The DOA technique is integrated over a medium voltage (MV) cable network and its performance is evaluated using ATP-EMTP environment. Frequency-dependent JMarti cable model is used for simulation. An intelligent algorithm is proposed for practical implementation of DOA technique for PD monitoring and automated location. Proposed scheme can be adopted in distribution automation system to improve proactive diagnostic capabilities of the network.

In this paper a detailed description of different passive shields for Extremely Low Frequency (ELF) applications is presented. The first part of the paper analyzes ferromagnetic and conductive materials by means of simulations and measurements. This step is mainly devoted to the identification of physical characteristics such as the relative permeability of the analyzed ferromagnetic materials. All the simulations are performed with a standard Finite Element (FE) code assuming linear behavior of the tested materials. The results are then used in the design of many shielding configurations and, finally, three different multilayer shield compositions are tested and presented. The second part of this paper outlines guidelines to assure a good shielding efficiency in the actual installation of a multilayer shield. The orientation of the shield as well as the possible decay of the shielding performance due to the discontinuity among the different slabs is investigated by means of experimental measurements. It is observed that the conductive part of the multilayer shield has to be faced to the source to have better performance. Moreover, it is important to assure the electrical conduction between the separate slabs. In this paper the conduction among different plates is conveniently obtained connecting them by straight bars of aluminum. In the third part of the paper the multilayer shield is tested under actual working conditions. A MV/LV substation was reproduced in the laboratory using a 630 kVA transformer working at its rated power. Several configurations were tested and the most significant results are presented. It is highlighted that, if the proper layout is not employed, the performance of the actual shield can be very different from the one of the material.

The paper focuses on the hazardous situations that can rise in urban areas in case of earth fault inside a High Voltage/Medium Voltage station. IEEE and IEC/EN Standards and technical documents are examined and discussed, in order to propose some practical guidelines for a safe integration of such installations in contexts characterized by the presence of low voltage systems and not trained persons.

Low-Energy District Heating (DH) systems, providing great energy savings by means of very low operating temperatures of 55 °C and 25 °C for supply and return respectively, were considered to be the 4th generation of the DH systems for a low-energy future. Low-temperature operation is considered to be used in a low-energy DH network to carry the heat produced by renewable and/or low grade energy sources to low-energy Danish buildings. In this study, a comparison of various design considerations with different levels of maximum design static pressures was performed, and their results evaluated in terms of energetic, exergetic, economic, and environmental perspectives.

Power devices intended for high-voltage systems must be tested according to international standards, which includes the short-time withstand current test and peak withstand current test. However, these tests require very special facilities which consume huge amounts of electrical power. Therefore, mathematical tools to simulate such tests are highly appealing since they allow reproducing the electromagnetic and thermal behavior of the test object in a fast and economical manner. In this paper, a three-dimensional finite element method (3D-FEM) approach to simulate the transient thermal behavior of substation connectors is presented and validated against experimental data. To this end, a multiphysics 3D-FEM method is proposed, which considers both the connector and the reference power conductors. The transient and steady-state temperature profiles of both the conductors and connector provided by the 3D-FEM method prove its suitability and accuracy as compared to experimental data provided by short-circuit tests conducted in two high-current laboratories. The proposed simulation tool, which was proven to be accurate and realistic, may be particularly useful during the design and optimization phases of substation connectors since it allows anticipating the results of mandatory laboratory tests.

The standard IEC61850 is presented, considering its implementation and application as a platform, from the point of view of electrical engineers rather than software and electronic engineers. This is important since electrical engineers are the staff responsible for the design, construction, operation and maintenance of the electrical substations. © 2016 IEEE.

A method to measure ground impedance in various soil structures is described, which takes into account inductive coupling between current and potential wires. For this purpose, a family of coupling effect curves versus the potential wire length was calculated. It was found that these curves are not dependent on the current wire length and are practically identical to the same soil resistivity. The true resistance of the substation grounding is determined using received coupling effect curves, and a simple formula which subtracts the coupling effect from the measured substation grounding resistance. Practical comparative measurements were performed to validate the method.

International audience; District Heating (DH) technology is an efficient and cost-effective solution to provide heating services to the built environment. However, the existing DH technology may not be technically and economically effective to service buildings with low energy demands. Here, low-temperature based district heating (LTDH) can provide a better match between supply and demand in terms of energy quality and quantity. This paper deals with the energy and exergy analyses of a LTDH substation supplying a secondary LTDH network as a subnet of the existing DH system. In order to improve the temperature match, a mix of supply and return streams from the primary DH network are used to supply the substation. Based on modelling and simulation, an energy and exergy analysis is employed to compare the performance of two proposed substation configurations to that of a conventional DH substation operating at low temperatures. The results show that the proposed LTDH substation reduced the share of the yearly energy demand of the LTDH network that is covered by the primary DH supply flow by 20% to 25%; the rest being supplied by the primary DH return flow. Likewise, by using the flow from the main DH return pipe, the final exergy efficiency of the overall system increased by 5% on average. The exergy destruction occurring at the system components was also identified and compared: during high heat demand periods the substation heat exchanger is responsible for the largest share of exergy destruction, whereas for low heat demands, it is due to the pumping effort. Based on these results, the proposed system is seen as an effective approach to increase the quality and quantity match between the low-temperature network and the conventional supply.

3rd International Istanbul Smart Grid Congress and Fair (ICSG) -- APR 29-30, 2015 -- Istanbul, TURKEY WOS: 000379385200010 This paper presents lifetime monitoring algorithm available for critical substation equipment. In the remaining life calculation stage, two proposed methods named the weighted moving average - based monitoring and the trend adjusted (double) exponential smoothing - based monitoring introduced, respectively. Both methods are evaluated for various cases and the validity of the first methods tested on the prototype transformer, experimentally. However, the second newly method has advantages such as wide forecast range, trend determination capability and insensitive to short term fluctuations. These methods with the algorithms are applicable for the instrument or its parts that aging characteristics can be expressed by the empirical equations under certain stress/stresses.

This paper describes software realization and its implementation for the communication, according to the IEC61850 standard, between the module for monitoring teleprotection devices and the control/monitoring server in a power substation. Teleprotection devices have an important role in the transmission of messages for power line section tripping. The software is implemented on the 'MSC nanoRISC-S3C2416 MB2' hardware platform type, which belongs to the COM (computer on module) systems.

Hardwired sensor installations using proprietary protocols found in today’s district heating substations limit the potential usability of the sensors in and around the substations. If sensor resources can be shared and re-used in a variety of applications, the cost of sensors and installation can be reduced, and their functionality and operability can be increased. In this paper, we present a new concept of district heating substation control and monitoring, where a service oriented architecture (SOA) is deployed in a wireless sensor network (WSN), which is integrated with the substation. IP-networking is exclusively used from sensor to server, hence, no middleware is needed for Internet integration. Further, by enabling thousands of sensors with SOA capabilities, a System of Systems approach can be applied. The results of this paper show that it is possible to utilize SOA solutions with heavily resource-constrained embedded devices in contexts where the real-time constrains are limited, such as in a district heating substation.

A reference setup for on-site calibration and validation of revenue metering systems is realized. The system consists of a three-phase power meter and high-accuracy current and voltage transformers (CTs and VTs). Measurements can be made up to 150 kV (system voltage) and line currents up to 5000 A. The power meter, the CTs, and the VTs were all calibrated. Based on the excellent results of the calibration of these components it is possible to predict the full system performance with an accuracy of 35 J.lWNA. This estimation was verified with a full system validation, showing that the system is much more accurate than required and that detrimental effects to the accuracy are well understood., Precision Electromagnetic Measurements (CPEM 2014), 2014 Conference on, 24-29 August 2014, Rio de Janeiro, Series: CPEM Digest

Background The past five years has seen considerable expansion of wind power generation in Ontario, Canada. Most recently worries about exposure to electromagnetic fields (EMF) from wind turbines, and associated electrical transmission, has been raised at public meetings and legal proceedings. These fears have not been based on any actual measurements of EMF exposure surrounding existing projects but appear to follow from worries from internet sources and misunderstanding of the science. Methods The study was carried out at the Kingsbridge 1 Wind Farm located near Goderich, Ontario, Canada. Magnetic field measurements were collected in the proximity of 15 Vestas 1.8 MW wind turbines, two substations, various buried and overhead collector and transmission lines, and nearby homes. Data were collected during three operational scenarios to characterize potential EMF exposure: ‘high wind’ (generating power), ‘low wind’ (drawing power from the grid, but not generating power) and ‘shut off’ (neither drawing, nor generating power). Results Background levels of EMF (0.2 to 0.3 mG) were established by measuring magnetic fields around the wind turbines under the ‘shut off’ scenario. Magnetic field levels detected at the base of the turbines under both the ‘high wind’ and ‘low wind’ conditions were low (mean = 0.9 mG; n = 11) and rapidly diminished with distance, becoming indistinguishable from background within 2 m of the base. Magnetic fields measured 1 m above buried collector lines were also within background (≤ 0.3 mG). Beneath overhead 27.5 kV and 500 kV transmission lines, magnetic field levels of up to 16.5 and 46 mG, respectively, were recorded. These levels also diminished rapidly with distance. None of these sources appeared to influence magnetic field levels at nearby homes located as close as just over 500 m from turbines, where measurements immediately outside of the homes were ≤ 0.4 mG. Conclusions The results suggest that there is nothing unique to wind farms with respect to EMF exposure; in fact, magnetic field levels in the vicinity of wind turbines were lower than those produced by many common household electrical devices and were well below any existing regulatory guidelines with respect to human health.

The development of a reference system for on-site calibration of revenue metering systems in high voltage grids is described. The system consists of a three-phase power meter and high-accuracy current and voltage transformers (CTs and VTs). Measurements can be made up to 150 kV (system voltage) and line currents up to 5000 A. The initial characterization of the power meter and the CTs give excellent results, indicating that an overall system uncertainty of 200 μW/VA can be achieved., 2012 Conference on Precision Electromagnetic Measurements (CPEM 2012), 2012-07-1 - 2012-07-6, Washington, DC, USA

Many substation applications require accurate time-stamping. The performance of systems such as Network Time Protocol (NTP), IRIG-B and one pulse per second (1-PPS) have been sufficient to date. However, new applications, including IEC 61850-9-2 process bus and phasor measurement, require accuracy of one microsecond or better. Furthermore, process bus applications are taking time synchronisation out into high voltage switchyards where cable lengths may have an impact on timing accuracy. IEEE Std 1588, Precision Time Protocol (PTP), is the means preferred by the smart grid standardisation roadmaps (from both the IEC and US National Institute of Standards and Technology) of achieving this higher level of performance, and integrates well into Ethernet based substation automation systems. Significant benefits of PTP include automatic path length compensation, support for redundant time sources and the cabling efficiency of a shared network. This paper benchmarks the performance of established IRIG-B and 1-PPS synchronisation methods over a range of path lengths representative of a transmission substation. The performance of PTP using the same distribution system is then evaluated and compared to the existing methods to determine if the performance justifies the additional complexity. Experimental results show that a PTP timing system maintains the synchronising performance of 1-PPS and IRIG-B timing systems, when using the same fibre optic cables, and further meets the needs of process buses in large substations Refereed/Peer-reviewed

This paper presents a new optimization approach of maintenance strategy for equipment in a transmission and distribution (T&D) system. In this approach, a present and future equipment performance is estimated by using monitoring data, and impacts of performance in each equipment on a whole T&D system are evaluated. By minimizing the impacts, suitable maintenance procedures and timing are derived. This approach is applied to a circuit breaker (CB) in an electric network, and its significance and usefulness are presented.

International audience; The deployment of IEC61850 standard in the world of substation automation system brings to the use of specific strategies for architecture testing. To validate IEC61850 architecture, the first step consists in validating the conformity of the object modeling and services implementation inside devices. The second step consists in validating IEC61850 applications compliance according to the project specifications. A part of the architecture can of course be tested "physically"; however in the design phase or when the actual architecture cannot be checked directly, modeling is helpful. In our research study we propose a co-simulation approach based on several components allowing the realization of advanced tests. This paper describes the need and the design implementation of software and hardware in the loop components as well as the object modeling concept of IED models.

The paper describes a probabilistic method for transmission grid security evaluation. Power system security is the ability of the power system to withstand sudden disturbances such as short circuits. The method presented here uses event and fault trees and combines them with power system dynamic simulations. Event trees model the substation protection and trip operations after line faults. Different event tree end states (fault duration, circuit breaker trips) are simulated with power system dynamic analysis program. The dynamic analysis results (power system post-fault states) are then classified into secure, alert, emergency and system breakdown. The probabilities, minimal cut sets and grid level importance measures (Fussell-Vesely, risk increase and decrease factors) are calculated for the total and partial system breakdown. In this way, the relative importance of the substation devices regarding to the system breakdown can be reached. Also the more and less likely contributing factors to system breakdown are received. With this method, an existing 400 kV transmission grid with its line fault and device failure statistics is analysed.

The design of a magnetic shielding arrangement for an indoor substation is considered. The aim of the intervention is to reduce the magnetic field intensity inside a room above the substation. Stray fields are mitigated by using metallic screens and by rearranging LV cables in order to limit intervention costs. A three-dimensional electromagnetic analysis of stray fields is performed by means of an original integral code, whereas a two-dimensional FEM software is used for assessing the shielding performance locally, in proximity of LV cables. Simulations show that the highest field attenuation levels are attained when phases of conductors and transformers are arranged in optimised configurations. The developed procedure is then applied to design a magnetic shield for a MV/LV substation. It is shown that measured and computed field r.m.s. values of the magnetic flux density are in good agreement.

One of the most important issues in DC electrified transportation system management is to perform, as far as possible, optimal operation in terms of economy, quality and reliability. In this paper a voltage control strategy is performed in order to minimize power losses and contemporaneously optimize the power sharing between feeding substations. The problem is formalized as a multiobjective optimization, this allowing to compare various solutions by simply varying the weights in the objective function. The control structure is designed according to a hierarchical architecture. For the traction load characteristics identification, an estimation algorithm is also described. In the last part of the paper a numerical application is presented, highlighting the feasibility and the goodness of the proposed strategies

This paper presents a computer-aided design of a transformer station grounding system. Fault conditions in a transformer station can produce huge damage to transformer station equipment if the grounding system is not designed properly. A well designed grounding system is a very important part of the project for transformer station design as a whole. This paper analyses a procedure for transformer grounding system design and spatial distribution of touch and step voltage on the ground surface level, using the CDEGS (Current Distribution Electromagnetic Interference Grounding and Soil Structure Analysis) software. Spatial distribution is needed for checking and finding dangerous step and touch voltages above and around the transformer station. Apparent earth resistivity data is measured and analyzed using the RESAP module of the CDEGS software. Because of the very high current flow into the grounding system during a single line to ground fault or a three phase fault in the transformer station, very high and dangerous potentials can be induced on the metallic structures including the fence, which can cause dangerous situations for people and animals near the station and for the personnel inside the station. The PLOT module of CDEGS is used to view the results of the scalar potential, step and touch voltage on the surface. Graphic displays include equipotent contour lines and potential profiles (gradients) in 3D and 2D perspective and apparent soil resistivity (Wm) versus inter electrode spacing (m). The results of alternative grid designs may be displayed simultaneously for the purpose of comparison.

The technological development of electrified railway systems during recent decades has demanded higher and higher quality performances of the supply subsystem. For this purpose, the recourse to electronics and to automation techniques can represent the right way to secure a reliable and efficient electric supply to the railway. The paper summarises the general problems of quality in railway electrification and proposes a new configuration of traction substations for single-phase AC-supply railways, based on the use of a two-phase inverter with nonlinear and variable-structure control system. Such an advanced technical solution allows one to obtain full compensation of load unbalances, constant load voltage, satisfactory power factor and a remarkable reduction of both disturbances and nonlinear-load effects. Some numerical applications show the efficacy of the proposed controlled compensator in containing disturbances and power-parameter variations, as well as its high performances in terms of fast response time, accuracy in steady-state conditions and general low sensitivity to disturbances.

This paper proposes a novel method for an optimal cabling route; a combinatorial design algorithm through heuristic mathematical formulations to choose the optimal path when two or more physical paths are available. The best path, from an EMC point of view, can be chosen based upon various criteria, such as monetary cost minimization, voltage drop and quality (EMC) parameters. This paper initially provides numerical 2D and 3D resolutions of the problems of radiation generated by current sources. The proposed approach is based on the finite element method, associated with absorbing boundary conditions. The presented model makes it possible to consider wave propagation and its effect on heterogeneous mediums in transient, which can be applied in EMC for simulation of radiation. Initially, the formulations for electromagnetic modeling of the proposed problem are specified in detail. The simulation results are used for the cabling routes, with respect to undesirable field distribution in the specified regions. Based upon the aforementioned criteria, using an Analytical Hierarchy Process, the intelligent choice of optimal cabling routes can be achieved. Hence, there is a need for the proposed method to be successfully implemented on two different types of power system; a current injection system, and high voltage substation.

The paper presents a real case of non-ionizing radiation testing in an apartment positioned next to “Belgrade 6” 110/35 kV substation. The measurements were performed in order to check the compliance of non-ionizing radiation levels in the apartment with the limits prescribed by Serbian regulations. The values of magnetic flux density obtained by measurements are significant due to very specific position of the apartment in relation to the substation, as both the apartment and the substation are located inside the same building. Moreover, the equipment in the substation is located very close to the apartment, essentially next to its wall and ceiling. Two main sources of the magnetic field in the apartment were identified on the basis of disposition of the equipment inside the substation. The first one are the 110 kV and 35 kV busbars located near the wall of the apartment, and the second one is the ripple control system located above the apartment. After the measurements were performed, some possible mitigation solutions based on passive shields were investigated by means of 3D simulations. The results of the measurements performed and the results of the shield design are shown in detail in the paper.