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In smart electric grid systems, various sensors and Internet of Things (IoT) devices are used to collect electrical data at substations. In a traditional system, a multitude of energy-related data from substations needs to be migrated to central storage, such as Cloud or edge devices, for knowledge extraction that might impose severe data misuse, data manipulation, or privacy leakage. This motivates to propose anomaly detection system to detect threats and Federated Learning to resolve the issues of data silos and privacy of data. In this article, we present a framework to identify anomalies in industrial data that are gathered from the remote terminal devices deployed at the substations in the smart electric grid system. The anomaly detection system is based on Long Short-Term Memory (LSTM) and autoencoders that employs Mean Standard Deviation (MSD) and Median Absolute Deviation (MAD) approaches for detecting anomalies. We deploy Federated Learning (FL) to preserve the privacy of the data generated by the substations. FL enables energy providers to train shared AI models cooperatively without disclosing the data to the server. In order to further enhance the security and privacy properties of the proposed framework, we implemented homomorphic encryption based on the Paillier algorithm for preserving data privacy. The proposed security model performs better with MSD approach using HE-128 bit key providing 97% F1-score and 98% accuracy for K=5 with low computation overhead as compared with HE-256 bit key. [ABSTRACT FROM AUTHOR]

As global concerns about climate change intensify, the transition towards zero-emission freight is becoming increasingly vital. Drayage is an important segment of the freight system, typically involving the transport of goods from seaports or intermodal terminals to nearby warehouses. This sector significantly contributes to not only greenhouse gas emissions, but also pollution in densely populated areas. This study presents a holistic optimization model designed for an efficient transition to zero-emission drayage, offering cost-effective strategies for the coordinated investment planning for power systems, charging infrastructure, and electric drayage trucks. The model is validated in the Greater Los Angeles area, where regulatory goals are among the most ambitious. Furthermore, the model's design allows for easy adaptation to other regions. By focusing on drayage trucks, this study also paves the way for future research into other freight categories, establishing a foundation for a more extensive exploration in this field. • Joint planning of charging stations and power systems. • Focus on heavy-duty drayage trucks. • Utilization of large-scale GPS data and electric substation data. • Over 200MW power capacity upgrades needed by 2030, even in optimistic scenarios. • Identification of the port area as a key hotspot for public truck charging stations. [ABSTRACT FROM AUTHOR]

The high-voltage direct current (HVDC) transmission system, which links the Gurun Substation of the National Electric Authority of Malaysia (Tenaga Nasional Berhad, TNB) with the Khlong Ngae Station of the Electricity Generating Authority of Thailand (EGAT), has been extensively researched to achieve the highest quality because it is the largest of its kind in Thailand, and there is a plant to expand its transmission power. However, the impact on the whole system is under-researched. To study and develop this system, the HVDC transmission line is modelled with the MATLAB/Simulink program and a laboratory setup to investigate the effect of transmission line distance, load power, and voltage on power loss, voltage drop, and waveform. The HVDC transmission line parameters are calculated from the actual transmission line parameters and converted to the simulation model parameters using the per-unit method. The model is verified and tested by the simulation program before creating the experimental setup. The simulation and experimental results demonstrate the effects of changing system conditions via the three aspects. All the three conditions directly affect the HVDC transmission line; nevertheless, they affect each aspect differently. [ABSTRACT FROM AUTHOR]

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Infrared image recognition plays an important role in the inspection of power equipment. Existing technologies dedicated to this purpose often require manually selected features, which are not transferable and interpretable, and have limited training data. To address these limitations, this paper proposes an automatic infrared image recognition framework, which includes an object recognition module based on a deep self-attention network and a temperature distribution identification module based on a multi-factor similarity calculation. First, the features of an input image are extracted and embedded using a multi-head attention encoding-decoding mechanism. Thereafter, the embedded features are used to predict the equipment component category and location. In the located area, preliminary segmentation is performed. Finally, similar areas are gradually merged, and the temperature distribution of the equipment is obtained to identify a fault. Our experiments indicate that the proposed method demonstrates significantly improved accuracy compared with other related methods and, hence, provides a good reference for the automation of power equipment inspection. [ABSTRACT FROM AUTHOR]

High dispersion of data, either obtained by field investigations, or created by time history analyses (THA), for developing fragility curves (FCs), results in remarkable uncertainty in seismic risk evaluation. Regarding the lack of studies on uncertainty reduction of FCs of electric power equipment, this paper presents three means for reducing this dispersion: (1) using spectral acceleration at fundamental period of the system, Sa(T1), instead of peak ground acceleration (PGA) as the intensity measure (IM), (2) using Sa(T1) + Sa(T2), as the IM, and (3) using a set of scenario earthquakes for THA instead of randomly chosen accelerograms. First, a brief history of FCs development for electric power equipment is presented, followed by a short review of the studies on improvement of fragility functions. Then, comparison of the mentioned methods for two key structures of electric substations, a post insulator (PI) and a current transformer (CT) is done. For the PI, first a set of randomly chosen accelerograms was employed, once using PGA, and once more Sa(T1) as the IM, and then a set of scenario-based records, with the same IMs. For the CT, first PGA, then Sa(T1) and finally Sa(T1) + Sa(T2) were used as the IM. Results show that using scenario-compatible records leads to more consistent data for developing the FCs, and that this consistency gets better and much better, respectively, by using Sa(T1) and Sa(T1) + Sa(T2) as the IM. It is suggested that for very high frequency systems, such as PI, Sa(T1) is used, while for moderate- and low-frequency systems, such as CT, Sa(T1) + Sa(T2) is used. [ABSTRACT FROM AUTHOR]

One of the important components of the passenger transportation system in many domestic cities is trolleybus transport, as one of the types of environmentally friendly urban passenger vehicles for public use. Since the beginning of the 2000s, in many countries of the world, its intensive development has been taking place at a new level thanks to the use of trolleybuses with autonomous running, capable of transporting passengers on sections of routes not equipped with a contact electrical network. The purpose of this study is to analyze the economic and social aspects of the development and use of trolleybuses with autonomous running in Ukraine. Based on the analysis of the main design parameters of trolleybuses with autonomous running, the effect of autonomous mileage on reducing the nominal passenger capacity without increasing the permissible gross weight regulated for classic trolleybuses and buses was assessed. The market value of new modern models of trolleybuses of Ukrainian and Belarusian manufacturers, equipped with various autonomous sources of electricity, in particular traction batteries and supercapacitors, was analyzed. The inadequacy of the market value of trolleybuses with autonomous running is shown, which is much higher than classic trolleybuses. A generalized evaluation indicator of the technical excellence of trolleybuses with autonomous running is proposed, which takes into account the total structural weight, nominal passenger capacity and autonomous mileage. Two options for the development of trolleybus transport and its integration into urban transport systems are considered, related either to the existing trolleybus electric networks or, in the near future, to the reconstruction and construction of more powerful electric substations for faster charging of autonomous sources of electric energy. Their implementation will ensure a significant increase in the autonomous mileage of trolleybuses without a significant increase in the capacity of autonomous sources of electricity. Proposed measures to ensure the active development of urban and suburban passenger transport systems based on the use of trolleybuses with autonomous running. [ABSTRACT FROM AUTHOR]

This article presents a new method for the estimation of active power losses based on a "field" approach, i.e., on the theory of the electromagnetic field and the theory of propagation of electromagnetic waves in a dielectric medium. Electromagnetic waves are assumed to transmit energy from the traction substation to electric rolling stock through the airspace of the inter-substation zone (i.e., not through the wires of the traction network) and meet electrically conductive surfaces on their way. The waves are partially reflected from the surfaces and partially penetrate them, thus creating thermal losses, the determination of which is the main task of this article. The analytical expressions for specific losses of active power are obtained by solving the system of Maxwell's equations. Calculations of specific power losses in the catenary, rails, roofs, and bottoms of carriages and electric locomotives are performed. Power losses in carriages and electric locomotives are found to be at least 7%. A comparative assessment of the magnitude of total power losses of different types obtained by the "field" and "circuit" approaches is provided, which has established that "conditional" losses correspond to losses in rails, train carriages, and electric locomotives. [ABSTRACT FROM AUTHOR]

A constant worldwide growing load stress over a power system compelled the practice of a reactive power injection to ensure an efficient power network. For this purpose, multiple technologies exist in the knowledge market out of which this paper emphasizes the usage of the flexible alternating current transmission system (FACTS) and presents a comparative study of the static var compensator (SVC) with the static synchronous compensator (STATCOM), inducted in a real electric substation. The aim is to improve the power factor (PF) and power quality and to encounter reliably extreme conditions. A 220 kV electric substation was opted for the analysis, and both the static and dynamic conditions were observed with the help of a power system analysis tool termed PowerFactory-DIgSILENT. Multiple aspects were investigated via software simulations to assess the performance of the aforementioned FACTS devices, such as the voltage profile evaluation via the load flow analysis method (LFA), the harmonic response via the power quality and harmonic analysis tool, and the short-circuit response via the RMS simulation tool. The outcomes were verified and compared with permissible values included in the universal standards, such as IEC and IEEE. The superiority of the STATCOM over the SVC was proven in light of the simulative results. [ABSTRACT FROM AUTHOR]

Historically, dense vegetation cover near buildings has caused power disruptions during weather phenomena. These types of severe storms impact the coast of Florida each year. However, challenges exist for obtaining both power outage data and calculating the impact of tree cover. NASA's Nighttime Lights, Black Marble, VNP46 product is utilized to analyze the natural and built environments. One aspect of the built environment that can be mapped with the Black Marble data is the megawatts of electricity used by the electrical power grid based on the magnitude of emitted nighttime light energy. This paper discusses using Black Marble data and other landscape variables within a probabilistic model to examine spatial patterns and map electricity outages with Bayesian networks. The research results indicate a high probability of a significant power outage when dense vegetation is present, but nuances in our natural and built environments like electric substations and land cover type alter the chance of reducing energy emissions. [ABSTRACT FROM AUTHOR]

Background: After notification of the Electricity Act, 2003, the Indian power sector has undergone a major transformation in bringing competition, in the development of electricity industry as a whole, protecting interest of consumers, ensuring supply of electricity to all, reduction of losses and rationalization of electricity tariff, etc. Enough generation capacity has been added, „Power for All? has been implemented in true terms, and both transmission and distribution network has been strengthened considerably. There is still enough work to be done in terms of 100 % metering, and reduction of line losses and commercial losses. Transmission and Distribution (T&D) losses are a percentage of energy lost in the power grid in the process of transporting electricity from generating stations to points of consumption. It is important to measure and understand the source of losses before tackling them. Energy audit of 11 kV lines and Distribution Transformers (DTs) comes into picture here. This paper discusses the challenges in performing the Energy audit in distribution sector and proposes few remedies for the same. Objectives: To understand the difference between the Technical loss, Commercial loss and AT&C loss in power distribution companies; To find out various ways of finding/calculating technical loss, commercial loss and AT&C loss in power distribution companies; To know the significance and method of calculating the Energy Audit of 11 kv feeders and Distribution Transformers; To list out the challenges faced in finding out the Energy Audit of 11 kv feeders and Distribution Transformers; To explore remedies to perform effective energy Audit. Methods: In this paper, various methods of finding out the 11 kv feeder energy audit are discussed. The challenges faced in performing such audit are also listed out. Few remedies to do the audit in a better way is also discussed. [ABSTRACT FROM AUTHOR]

Aiming at the recovery and utilization of train electric braking feedback energy, this paper analyzes the train operation characteristics, and focuses on the relationship between the train operation process and the voltage fluctuation of the traction network. Combined with the dynamic mismatch between the power supply of the traction substation and the electric power of the train, the scheme of the on-board braking energy recovery and utilization system is adopted, and a supercapacitor charging and discharging control strategy based on the dynamic change of the electric power of the train is proposed. The scheme is mainly composed of super capacitor series-parallel energy storage unit and bidirectional DC-DC converter. In this paper, MATLAB is used for modeling and simulation analysis. The simulation results show that the control strategy can effectively recover and utilize the train braking energy while suppressing the voltage fluctuation of the traction network, which provides an effective solution for the recovery and utilization of the train braking energy. [ABSTRACT FROM AUTHOR]

A Virtual Reality System provides an intuitive tridimensional user interface, with distinct interaction when compared to a traditional 2D layout, allowing the user to manipulate data similar to the real world. Such systems give the users physical and cognitive immersion, by granting a mental model compatible with field operation. In this work, we present the development aspects and some results of a Virtual Reality based solution to provide a more natural and intuitive environment for controlling electrical operation centers. The solution intends to minimize the issues caused by the operation of electric power substations due to the lack of spatial and functional information on the traditional operation interfaces. The research is being carried out with the collaboration between the energy electric company of Minas Gerais–Brazil (CEMIG) and the Federal University of Uberlândia. Besides operating generation and transmission actives, the environment presents great potential for the training of operators and other professionals of support and maintenance. [ABSTRACT FROM AUTHOR]

We could get many helpful information and results from satellite remote sensing images and aerial images, including disaster monitoring, grid hidden danger identification, and electricity consumption management. In the recent years, novel computer vision and deep neural network have got a lot of attention in many fields because of mimicking mammalian cognitive mechanism as much as possible. With the in-depth of mammalian cognitive and motor mechanisms research, people trend to adopt these reliable and efficient methods for power grid management and maintenance.For utilizing computing resources and improving analysing efficiency flexibly, we propose an assessing and verification framework based on bio-inspired perception and understanding, which summarizes the most appropriate image scale in the electric facilities place recognition. The proposed framework consists of different scenes aerial images datasets, several electric facilities place recognition methods, and credible evaluating methods mimicking mammals. Firstly, we gather satellite remote images and aerial images of sufficient electric power facilities in the United States via Google Earth and other public datasets. Then, several typical place recognition methods are adopted to testing recognition ability of multi-scale perception results, like SAD, NetVLAD, and GIST descriptor. To get more reliable result, multi-units and multi-scenes experiments are implemented roundly. After all experiments and evaluations, we could get that the most appropriate image scale is 1000 m size and the highest recognition accuracy of electric power facilities location is 500 m. Conclusion in our article shows the recommended perception form and scale closest to human cognition in the power grid management and maintenance. [ABSTRACT FROM AUTHOR]

Solar farms are becoming a crucial part of the renewable energy mix. Yet, the literature has not reported a generalized approach to its design. In this regard, this paper attempts to provide a detailed plan of a 5-MW grid-connected solar farm. In addition, the procedure to analyze the land footprint of the solar plant is also developed. At first, the main components of the solar farm are selected qualitatively. Then, using an excel spreadsheet, the sizing of photovoltaic (PV) array, inverters, combiner boxes, transformers, cables and protection devices is carried out. Finally, the land footprint analysis of the proposed solar farm was carried out mathematically. The proposed solar PV power plant comprises 13 490 numbers of PV modules with a 365-W rating. Nineteen numbers of PV modules will constitute a string. One hundred forty-two numbers of strings will be connected to an inverter of 1 MW rating. The energy output from five such inverters will be fed to the nearest electric substation using a transformer of 1 MVA capacity. The DC and AC cables having a voltage drop of less than 1% are selected. The inter-row distance and ground coverage ratio (GCR) are estimated as 1 and 0.78 m, respectively. The required number of mounting module structures is found to be 710. The proposed solar farm's total land use requirement is ~43768.41 m2 (around 3 acres). It was observed that the sizing of solar plant components mainly depends on the electrical parameters of the PV module and inverter selected by the designer. Similarly, the land use requirement is influenced by the inter-row distance and PV site layout. This research is expected to streamline the different approaches of solar farm design, which will be beneficial to energy professionals and policymakers. [ABSTRACT FROM AUTHOR]

Protection is a safety in the electric power system installed in the electric power distribution system, power transformer, electric power transmission, and electric generator used to secure the power system electricity from electrical disturbances or overloads by separating the disturbed parts of the electric power system from the undisturbed electrical power system so that the undisturbed electrical system can continue to work. The protection system at the T75B substation has a work failure where when there is a short circuit on the consumer side, it causes the PMT (Power Breaker) for the Malibu Feeder at the Kebon Sirih Substation to trip while the CBO (Circuit Breaker Outgoing) cubicle at the T75B substation does not trip. This resulted in an unexpected widespread blackout. To find out the cause of the failure of the protection system, several tests and analyzes were carried out, namely protection design testing, protection relay coordination testing, protection system construction analysis, protection equipment performance testing. It is hoped that the test results can be used as a reference for improvement so that similar failures do not recur. [ABSTRACT FROM AUTHOR]

This paper deals with the sizing of stocks of spare transformers and mobile units, necessary to maintain the reliability of a set of substations of electric energy distribution. Two types of failure are considered: (i) catastrophic, in which the transformer suffers unrepairable damage and must be replaced by a new one and (ii) random, when the transformer can be repaired in the substation itself, not requiring its replacement by a spare. Two probabilistic methods are considered based on: Markov process and chronological Monte Carlo simulation (MCS), both implemented in Matlab environment. Initially, the methods are applied to the same set of transformer class and a comparison with results from the literature ensures the validation of the tested models. Because it is more flexible and capable of incorporating operational conditions not supported by the Markov model, the chronological MCS method is chosen to perform a series of numerical applications with a real system considering factors such as: load transfer, increase in the number of transformers in operation, inclusion of reinforcements to the stock of spare transformers and mobile units. Several sensitivity analyses are carried out to identify, from the reliability indices and operating costs, the factors that most influence the system performance. [ABSTRACT FROM AUTHOR]

Since the "big five," the proposed large-scale planning and construction system of substations has seen rapid development, providing enough energy for people while also causing a series of problems, such as a gradual increase in radiation and magnetic fields. It not conducive to artificial operation, such as in case of frequent high-voltage electrical equipment failure, which again negatively influences the whole electric power system operation. Especially, the electrical failure of high-voltage equipment, if not found and solved in time, could cause a major power accident, bring economic losses to the power company, and even threatening the life safety of staff. None of these risks can be ignored. Based on this, in order to reduce the risk of substation accidents and to promptly discover and solve the problem of electrical failure in high-voltage equipment, this paper studies the substation in BX area as an example, by using the frequency response method, such as a low impedance of transformer for the winding deformation test. The winding has carried out with the handover testing and hoisting cover inspection With the collapse of the experiment, not only are the problems causing the fault found, the fault type and location are also determined. The feasibility of this method for detecting electrical faults of high-voltage equipment is confirmed, and the fault characteristics, location, and other information can be accurately judged, which provides support for the formulation of fault strategies in the later stage. [ABSTRACT FROM AUTHOR]

Phase synchronization can aid in understanding the dynamics of underlying systems. In an electric substation, disconnect, failures mostly occur due to overheating. In this work using the Hilbert transform to assess the phase synchrony of a disconnect temperature and its relationship with meteorological variables and disconnect current can be helpful in understanding temperature influences and composition. Statistical methodologies, including entropy analysis, correlation, Kalman filter, Fast Fourier Transform, Augmented Dickey–Fuller test, and Kwiatkowski–Phillips–Schmidt–Shin test, were employed. One of the differentials of this study is the use of the median filter, which was able to access the phase synchrony of the variables with disconnect temperature. An important result is that current is not the most correlated variable with disconnect temperature, instead, air temperature exhibits the highest correlation, and the highest phase synchronization is only obtained when disconnect current and air temperatures are combined. This study contributes to the advancement of power substation operations, advocating for continuous monitoring and analysis to ensure a reliable electricity supply obtaining better predictive maintenance. [Display omitted] • The median filter facilitates access to phase synchronization information. • The combination of air temperature and current demonstrates the highest level of synchronization information. in the disconnect temperature. • Solar incidence decreases synchrony. • The disconnect temperature, disconnect current, and air temperature share the same frequency modules. • Night-time phase synchrony is higher. [ABSTRACT FROM AUTHOR]

This study investigates the spatial characteristics of existing utility-scale solar energy (USSE) development in New York State (NYS) and assesses the land-suitability for the future development of USSE needed to achieve the State's renewable energy goals using GIS-MCDA techniques. Slope, proximity to electric substations, protected lands, and soil quality were used as criteria to develop land suitability scenarios. 40% of present USSE capacity has been developed on agricultural lands, and 84% of identified land suitable for future USSE development (∼140 GW potential) is agricultural. The USSE potential on non-agricultural land is 22.5 GW – just sufficient to accommodate the development of 21.6 GW, which is the estimated USSE capacity that will be required to achieve NYS's 2030 goal of 70% renewable electricity. Thus, agricultural lands will be the prime target for future USSE development. Exploring the state-specific synergies for solar-agriculture colocation, preventing the spatially-concentrated development of USSE, and incentivizing the use of unproductive agricultural lands will help mitigate negative impacts of USSE development on agricultural lands. [Display omitted] • 44% of existing utility-scale solar in New York is developed on agricultural lands. • 84% of suitable land for future utility-scale solar in state is agricultural. • Solar growth should protect prime farmland and encourage agrivoltaics. • Spatial distribution and development on marginal lands should be incentivized. • Decision-making processes need to encourage proactive community involvement. [ABSTRACT FROM AUTHOR]

A mobile electromagnetic environment (EME) monitoring system for electric substations is presented that has been designed to register in real time the levels of electromagnetic interference that can degrade the quality of operating technical means, the purpose of this being to identify systematic disturbances of electromagnetic compatibility and establish the causes of these disturbances. Such interference includes impulse noise arising from lightning strikes, short circuits, and primary equipment switching; overvoltage affecting secondary equipment circuits; fails dips and interruptions in power supply of operating 0.4-kV auxiliary ac/dc systems; and magnetic fields in rooms with technological control systems. The system architecture allows it to be quickly transported and deployed at existing electric substations, which are of the most interest in terms of the EME control. The key functions of the monitoring system are implemented using digital EME recorders and tapped primary measuring data transducers (sensors). The recorder is a digital multichannel oscilloscope equipped with a measuring data solid-state drive and a wireless interface providing access to this data from a master computer. The monitoring system will prevent major accidents at power facilities due to the timely detection of EME deterioration and elimination of EMC violations, as well as collect objective evidence to analyze their triggers. [ABSTRACT FROM AUTHOR]

The aims of this study are to provide a strain and its optimal application in electro-producting performance for revealing the electrical generating mechanism in the future. We constructed microbial fuel cells (MFCs) device that was a bipolar chamber MFC, using metal ion media (MIM) and water as anode and cathode reaction substation fluid, respectively. In this study, we identified an isolate as Raoultella terrigena, named RtZGl, which could produce electron. Also, we optimized the conditions of electrical energy generation. The continuous output current could reach about 200 pA within 3 h when the ratio of electrobacterial fluid to matrix fluid was 1: 4, the temperature was 37 °C, the carbon-nitrogen ratio of the inorganic salt medium was 10: 1, as well as the concentration of MIM was 1. Based on the optimization, it is clear that the most suitable conditions of electricity production for this strain lay the foundation for the application of this strain. [ABSTRACT FROM AUTHOR]

The earthing system is very important to safe human’s lives and protect power system from normal and abnormal faults. High soil resistivity regions is the main problem of installation the earthing systems in electric power substations to pass the current through the earth's surface. This paper has been overcome on high soil resistivity regions by penetrating conductive nanoparticles to have extremely low grounding resistance. Moreover, it has been succeeded to examine the methodology of the proposed Nano-Tech earthing systems in case of single rods, multiple rods and grids. Also, it has been defined optimal types and concentrations of nanoparticles for Nano- Tech grounding system to provide excellence protection for electrical substations with respect to built beneath of soil where substation is located. A comparative study has been discussed and analyzed the results of traditional and nanotechnology grounding systems. [ABSTRACT FROM AUTHOR]

Based on analysis of the problem of the power supply networks of railways innovative transformation, the direction of research is substantiated related to organization of the optimal strategy of computerized intellectualization of the power supply processes to the railways traction substations. The logical structure of a distributed computer environment developed in the form of graph, which adequately reflects the topology of the organization of the power supply system. A differential mathematical model of the computer architecture of the power supply control is proposed. An intelligent method for finding the optimal strategy for the intellectualization of the power supply processes was proposed to guarantee the specified indicators of the optimal functioning of individual nodes and segments of the power supply management computer network. [ABSTRACT FROM AUTHOR]

The increasing adoption of the Industry 4.0 paradigm encompasses digitally interconnected factories which enables many advantages. However, it is still necessary to dedicate effort towards investigating protection mechanisms against cyberattacks in these scenarios. Despite the power demonstrated by Anomaly Detection-based Intrusion Detection Systems in industrial scenarios, their vulnerabilities to adversarial attacks, especially to evasion attacks, make Machine Learning and Deep Learning models ineffective for real scenarios. These type of attacks craft samples misclassified by the Intrusion Detection System and potentially reach industrial devices, causing potentially damaging impacts to factory workers and industry resources. Adversarial attacks linked to industrial scenarios are currently in early stages of development, hence most of them have the capability to craft samples misclassified by the IDS but not reach industrial devices. In this work, we present a new adversarial attack named Selective and Iterative Gradient Sign Method that overcomes the limitation of the adversarial attacks present in the literature. To complement this work we also detail a study of how the detection rate of an Intrusion Detection System is degraded and the time required by each technique to generate adversarial samples. The experiments were carried out using a dataset named Electra, collected from an Electric Traction Substation, and showed that adversarial attacks evaluated crafted samples misclassified by the IDS. However, only the method we proposed generated samples that can be understood by intermediate network devices and, therefore, reach their destination. Our experiment outputs demonstrate a lower period of time to achieve and craft adversarial samples using out our iterative based process method as opposed to other current iterative methods currently available. [ABSTRACT FROM AUTHOR]

Geomagnetically induced current (GIC) in utility systems such as electric power grids occurring during extreme geomagnetic storms can exceed the tolerance limit of the systems, which can cause serious system damages. It has therefore been important to evaluate the GIC levels in the utility systems. This study presents the simulation and analysis of GIC levels in the Shandong 500 kV power grid system consisting of 34 substations under a variety of uniform induced geoelectric fields. The line type, substation grounding resistance, and other influencing factors are included in the simulations. The results show that the GIC level varies largely in the 34 substations. In 11 substations, the GIC exceeds 100 A and it reaches up to ∼200 A in two substations for an assumed 1 V/km induced electric field. The changes in the GIC distribution are found consistent with the direction changes of the electric field. Utilizing the directional sensitivity, we calculate the maximum GIC level for the optimum direction for all substations. By combining this information with statistical tools, we propose a method for identifying the key substations which are most vulnerable. The result can provide suggestions for GIC disaster prevention and mitigation, substation site selection, monitoring equipment installation, and so on, in Shandong province. Key Points: Geomagnetically induced current (GIC) levels in the Shandong 500 kV power grid system are simulated and analyzedIt is shown that GIC levels have high sensitivity to the direction of the geoelectric fieldBy calculating the maximum GIC level for the optimum direction for all substations, we propose a method for identifying the vulnerable substations [ABSTRACT FROM AUTHOR]

Based on the actual damage data of high-voltage electrical equipment in electric substations in the Wenchuan earthquake, this paper uses the cumulative Gaussian distribution function to describe the relationship between the damage rate of high-voltage electrical equipment and the instrumental seismic intensity. The instrumental seismic intensity at strong motion observation stations in the Wenchuan earthquake is calculated, and the Kriging interpolation method is used to estimate the instrumental seismic intensity at 110 kV and above voltage level substations in Mianyang, Deyang, Guangyuan, and Chengdu of Sichuan Province. A cumulative Gaussian distribution function is then used to fit the damage rate-instrumental seismic intensity relationship curve for six types of high-voltage electrical equipment such as the transformer, circuit breaker, voltage mutual inductor, current mutual inductor, isolating switch, and lightning arrester. The results show that transformers have the highest vulnerability during earthquakes, and they suffered a certain level of damage even under low instrumental intensity. The second most vulnerable equipment is the circuit breaker, followed by the lightning arrester, transformer, and isolating switch, which share a similar vulnerability curve. [ABSTRACT FROM AUTHOR]

This work is dedicated to the economic scheduling of the required electric stations in the upcoming 10-year long-term plan. The calculation of the required electric stations is carried out by estimating the yearly consumption of electricity over a long-time plan and then determining the required number of stations. The aim is to minimize the total establishing and operating costs of the stations based on a mathematical programming model with nonlinear objective function and integer decision variables. The introduced model is applied for a real practical case study to conclude the number of yearly constructed stations over a long-term plan in the electricity sector in Jeddah City, Saudi Arabia. The current planning method is based only on intuition by constructing the same number of required stations in each year without searching for better solutions. To solve the introduced mathematical model, a novel recent gaining sharing knowledge-based algorithm, named GSK, has been used. The Augmented Lagrangian Method (ALM) is applied to transform the constrained formulation to become unconstrained with penalization to the objective function. According to the obtained results of the real case study, the proposed GSK with ALM approved an ability to solve this case with respect to convergence, efficiency, quality, and robustness. [ABSTRACT FROM AUTHOR]

High time resolution (1–5 s) magnetometer, geomagnetically induced current (GIC), and mains harmonic distortion data from the Halfway Bush substation in Dunedin, New Zealand, are analyzed. A recently developed technique using very low frequency (VLF) radio wave data provides high‐resolution measurements of mains harmonic distortion levels. Three case studies are investigated, each involving high rates of change of local geomagnetic field, but with different timescales of magnetospheric driver mechanisms, and different substation transformer configurations. Two cases of enhanced GIC during substorm events are analyzed, and one case of a storm sudden commencement. Time delays between magnetic field fluctuations and induced transformer currents are found to be ~100 s for substorm events, but only ~20 s for the storm sudden commencement containing higher‐frequency variations. Boxcar averaging of the magnetic field fluctuations using running windows of ±2 min leads to spectral power profiles similar to those of GIC profiles, with reduced power at frequencies >0.003 Hz (periods <5 min). Substantially lower mains harmonic distortion levels were observed after the removal of the single phase bank transformer, HWB T4, from the high‐voltage configuration at Halfway Bush. No systematic time delay was found between GIC variations and mains harmonic distortion levels. The power spectra of magnetic field fluctuations and GIC variations during the sudden storm commencement with no harmonic distortion showed low levels of low‐frequency power (<0.003 Hz, periods >5 min). This low‐frequency component of the magnetic field power spectrum appears necessary for mains harmonic distortion to occur. Key Points: High time resolution magnetic field, geomagnetically induced currents, and mains harmonic distortion data are analyzed for three case eventsObserved delays of 20–128 s between magnetic field and induced currents, but no delay between induced current and harmonic distortionEnhanced spectral power in induced current at frequencies <0.003 Hz (period >5 min) are required to produce harmonic distortion [ABSTRACT FROM AUTHOR]

Ensuring reliable operation of power transformers as part of electric power facilities is assigned to the maintenance and repair system, whose important components are diagnostics and monitoring of the technical condition. Monitoring allows you to answer the question of whether the transformer abnormalities and how to do they manifest, while diagnostics allow determining the nature, the severity of the problem, determine the cause and possible consequences. The article presents the results of the author's research on creating an algorithm for adaptive control of the technical condition of power transformers using diagnostic and monitoring data. The developed algorithm implements the decision-making procedure for ensuring the reliable operation of oil-filled transformer equipment as part of the substations of electric power facilities. The decision-making procedure is based on the method of statistical Bayesian identification the states of a transformer based on the results of dissolved gas analysis (DGA) in oil. The method is characterized by high reliability of recognizing defects in the transformer and the ability to adapt the probabilities of the obtained solutions to the newly received diagnostic information. These results illustrate the effectiveness of the developed approach and the possibility of its application in the operation of oil-filled transformer equipment. [ABSTRACT FROM AUTHOR]

Generic Object Oriented Substation Event (GOOSE) message reflects the transmission of information between many intelligent electronic devices, which is more reliable as original data. The communication Ethernet opaque also leads to a big problem of information extraction analysis, limiting the development of state maintenance and other techniques. This study describes the process equipment and the network transmission technology of the intelligent substation and analyses the specified message format of IEC61850. The study then compares it with the characteristics of the typical intelligent substation message and gives the analysis method and the meaning of each byte in the actual message frame, making the communication network in the process layer more transparent and giving a clear direction of information acquisitions and analysis. It also provides some reference meanings to the intelligent substation communication and the equipment status analysis. [ABSTRACT FROM AUTHOR]

The drive towards low-carbon economy in South Africa has necessitated alternative energy sources for electricity generation. More alternative sources have evolved in recent times with a view to making energy available to all and sundry. However, asides proliferation of these sources and extensions in form of micro-grids, the questions of increased availability and sustainability has become a growing concern. This survey investigates the state of the renewable energy system in South Africa with focus on the elements, which enhance energy availability and sustainability in the emerging transition to a low-carbon economy. Case studies of other countries were reviewed and considered in the South African context. It was observed that energy availability on the journey to the low-carbon economy is influenced by physical, climatic, human, prosumer concept and political factors. In sustaining the transition and progressing to a green economy, intelligent use of data from power generation, transmission, and distribution sectors for intelligent data-driven decision-making processes was also found as essential. As part of the sustainability roadmap, efficiency at the end-user side of the value chain and a system thinking paradigm in the harvesting of renewable energy sources (RES) and formulation of supporting policies were also identified. In the overall, the study reveals that South Africa is replete with abundance of RES, however, their continuous availability and sustainability depends on joint interventions of both stakeholders and the government with viable environment for the growth of the sector. [ABSTRACT FROM AUTHOR]