Electric Facilities Research Articles

Design of Monitoring System for Electric Vehicle Charging Facilities Based on Cloud Platform

Faced with the increasingly severe pressure of traditional energy consumption and environmental problems, electric vehicles have become the hotspot and trend of the development of the world automobile industry due to their energy-saving and environmental protection characteristics. The cloud platform in the paper was introduced into the monitoring system of electric vehicle charging facilities, and a model of electric vehicle charging facility monitoring system based on cloud platform was proposed. Aiming at the difficulty of charging facility monitoring system in large concurrent data processing, a M/M/C queuing theory model was presented. Data concurrency control algorithm. The transmission process of the data frame in the monitoring system was analyzed, and the concurrent processing algorithm was applied to the large charging station for analysis experiments. The experimental results showed that the proposed algorithm not only satisfied the real-time and concurrency requirements of data frame transmission, but also proved that the gateway optimization method could accurately derive the optimal number of gateways.

An Exploration of Environmental Practices in the Hospitality Industry. Evidence from Hotels in Addis Ababa, Ethiopia

Hotels create unforeseen damages to the environment by depleting natural resources and driving out wastes. Studies have rarely been conducted to investigate the nexus between hotels and the environment in Ethiopia. This study aims to explore environmental practices among Addis Ababa hotels. The quantitative research design was applied to the study. The data were gathered through a self-administered questionnaire and analyzed through descriptive statistics. The totels' environmental practice indicators were examined under the themes of water-saving, energy-saving, green purchase, and waste management. Within these themes, the installation of energy-efficient bulbs, installation of a key card for light; using energy-efficient appliances; regular maintenances of water and electric facilities; the installing of dual toilet and other low flow water technologies; placing of dustbins; sorting and disposing of solid wastes, and buying of local products were implemented to a certain extent. The study implicates the requirement of intervention to make hotel operation environmentally sustainable.

Pareto optimality in cost and service quality for an Electric Vehicle charging facility

This paper examines the problem of planning an Electric Vehicle (EV) charging facility that provides a high quality of service in charging EVs and incurs a low cost to the facility manager. This problem is challenging because a facility with a larger charging capacity (hence better service quality) can be more expensive to build and operate. This paper contributes to the literature by planning an EV charging facility that overcomes this trade-off and achieves Pareto optimality, i.e. a facility with a higher quality of service but at a lower cost. We propose an optimization model to size an EV charging facility that minimizes the facility cost and guarantees a high quality of service. To reduce the cost further and negate the cost increase from quality service quality, we adopt demand management strategies. Two strategies are explored, namely Stationary Demand Management (a local energy storage system) and Mobile Demand Management (rescheduling charging sessions of EVs). The proposed model produces a facility that guarantees a high quality of service in charging EVs at a minimal cost. A facility with demand management strategies achieves a higher service quality but at a lower cost, compared to a facility without demand management strategies. Stationary Demand Management can reduce the cost similarly to Mobile Demand Management, while the latter can be more challenging in practice due to the compliance issues and demand uncertainty of the drivers.

Evolutionary Approaches to Fog Node Placement in LV Distribution Networks

Smart grids merge intelligent computing technologies and electrical grid networks for better monitoring, control and management of electrical energy and facilities. The maturity of cloud computing has been the major driving factor for its adoption in smart grid deployments. Despite the elasticity of cloud resources, centrality and long distances to remote data centers cause high latency, high bandwidth consumptions and unstable connectivity, which are undesirable for IoT-based smart grid applications. Fog computing as an extension of cloud computing services to the edges of the network overcomes these challenges and perfectly suit the distributed nature of the low voltage (LV) electrical distribution networks as part of smart grid. The pressing issues with the adoption of fog computing for smart grid applications are finding the best placement plan for fog node locations in LV distribution networks to enhance monitoring and control. The main goal of this work is to present a mathematical model to address the aforementioned issues focusing on minimizing deployment cost and network delay. In addressing this multi-objective problem, a new algorithm, namely Future Search Particle Swarm Non-dominated Sorting Genetic Algorithm (FPNSGA), is proposed based on the combination of the best features of the NSGA-II, SMPSO, and a recently formed algorithm, Future Search. The effectiveness of the algorithm is evaluated based on the benchmarking technique (Weighted Sum approach), the convergence and diversification of the solutions using HV indicators and CPU time. The results from simulations show that the proposed mechanism is very competitive and outperforms other fog planning network schemes.

Digital technologies for managing anthropogenic risks in electric power industry

The article examines the information and analytical technology implemented during the operation of electrical networks, based on the capabilities of multi-agent monitoring of the somatic and mental condition of the staff of power grid companies and predictive analysis of anthropogenic risks of energy production within the framework of a risk-based approach to human resource management. The analysis includes instrumental monitoring, assessment of indicators (using objective data) characterizing the condition of operational managers, operational and maintenance staff involved in real technological and business processes for servicing equipment of network companies using optimization theory methods, fuzzy sets, index analysis, provision of integral information to operational managers and management of energy companies, the formation of proposals on the areas of investment in the development of their human resources based on solving the optimization problem of minimizing damage due to wrong actions, inaction and violation of safety requirements for energy production. It is proposed to use a system of dimensionless index indicators for assessing the condition of staff, predictive analysis of the success of their professional activities and the formation of its ontological model in order to manage anthropogenic risks to ensure reliable and safe functioning of energy production with the possibility of developing measures and scenarios of impacts on staff within the production process. The article presents approaches to the formation of monitoring technology, which ensures the construction of unified systems for recording the condition of staff operating electric power facilities, statistics of failures due to staff's fault to determine the optimal type, composition and cost of impact on staff, improving their health based on multi-agent analysis of monitoring data, allowing to direct the flow of events in accordance with the conditions set by the availability of funds for these purposes. The authors have developed a mathematical apparatus, proposed devices and software, with the help of which an automated analysis of the indices of the condition of staff of each category, servicing equipment units (assemblies) and the formation of scenarios of impacts on it (agent-based modeling of condition-controlled behavior) has been carried out.

Failure mode and reliability study for Electrical Facility of the High Temperature Engineering Test Reactor

The first-of-a-kind commercial electricity and hydrogen cogeneration system is being designed by the Japan Atomic Energy Agency (JAEA) to establish the industrial application of the High Temperature Gas-cooled Reactors (HTGR). The High Temperature Engineering Test Reactor (HTTR) is expected to be coupled with a test cogeneration plant to demonstrate its safety features and justify further HTGR technology development. The aim of this work was to assess the frequency of the unplanned outages of such a plant due to the failures of the HTTR Electrical Facility. The system analysis has been performed followed by the Failure Mode and Effect Analysis (FMEA). The new FMEA-based Gradual Screening Approach has been proposed and applied in order to select the most relevant failure modes. The initial calculation performed for the standard configuration of the system indicated that the reliability may be insufficient for its long-term commercial operation, as planned for about 20 years. Therefore, several modifications of the design have been proposed, aiming at the reliability enhancement. However, the updated results are still below the industrial standards. This opens up a new field of research in reliability engineering and creates a challenge for the HTGR-based cogeneration plants consisting of the joint nuclear-chemical facilities.

Attachable Magnetic-Piezoelectric Energy-Harvester Powered Wireless Temperature Sensor Nodes for Monitoring of High-Power Electrical Facilities

In this paper, we report attachable magnetic-piezoelectric energy harvester powered wireless temperature sensor nodes for monitoring of high-power electrical facilities. Each of sensor nodes consists of a magnetic-piezoelectric energy-harvester, power-management circuit, energy-storage capacitor, wireless transmitter, and temperature sensor. To harness different levels of magnetic-field energy induced by wires/conductors operated at different current levels in high-power electrical facilities, we design energy harvesters with different mechanisms specifically for above levels. These include a force-deflected cantilever energy harvester, force-deflected simple-beam energy harvester, and strain-mediated magnetoelectric (ME) energy harvester. The above energy harvesters powered sensor nodes are attached on an industrial standard copper bus-bar carrying different ultra-high currents to test their energy-harvesting and temperature-monitoring performance. The test results show that the maximum current-carrying capacity of the copper bus-bar for the cantilever-beam, simple-beam, and magnetoelectric energy harvesters are 266 A, >900 A, and >900 A, respectively. Based on this, the energy harvesting performance of the cantilever, simple-beam, and ME energy-harvesters powered wireless temperature sensor nodes are 966 μW at 260 A, 526 μW at 700 A, and 59.8 μW at 700 A, respectively, and the corresponding cycle time of wireless temperature sensing are 3.5 minutes, 6 minutes, and 99 minutes, respectively. According to these results, the sensor nodes not only successfully achieve temperature sensing/monitoring of ultra-high-current electrical facilities, but also provide total solutions for electrical facilities with different power/current specifications. These results will be important fundamentals toward wireless sensors network (internet of things) for temperature monitoring of high-power electrical facilities.

접지봉 매설을 위한 유도공 굴착장치 및 탄소접지동봉 활용 접지저항 경감 방법

In korea, the electric facilities and communication equipments have been built with a grounding construction in order to protect human life from electrical shock of lightning/ surge voltage and secure the performance of electric appliances and rapid emit an impulsive current into underground for safety. Also, the value of grounding resistance of the electric facilities was legislated to certain resistance value in korea and it should be perform the reinforcement construction for maintaining less than the specified value. But it’s very hard to carry out the grounding reinforcement construction without any damage on the seven underground utilities scattered around underground of downtown area. Futhermore, although it is inevitable to use additional resistance reducing materials for qualifying the value, but the porosity of ground and resultant loss of reducer make that uncontrollable. Therefore we had to seek the process of minimizing the economic loss and basically preventing the national property loss, negligent accident, futhermore, appling the method of cost reduction as well.

Hybrid nanocomposites of a molybdenum disulfide (MoS2) based hydrophobic filler for a robust self-cleaning effect

This work has been sought to improve the self-cleaning effect in insulators and insulating covers made of polymer material used in electric supply facilities by modifying their surface hydrophobicity. The multilayers 2D nanosheet MoS2 was exfoliated into a single or several layers to obtain a highly flexible nanostructure. MoS2-intermediate derivate was formed by disulfide bonds via a reaction between the thiol groups of cysteine and the sulfide groups of the outer layers of MoS2. This MoS2-intermediate derivate was reacted with polydimethylsiloxane to fabricate hybrid organic-inorganic nanocomposites fillers, then, the adhesion, mechanical strength, and surface roughness were determined. A 7.5wt% nanofiller-containing polymeric insulator and insulating cover exhibited an increasing in receding contact angle of about 20°–36° compared to the pristine material. This work demonstrated the self-cleaning properties as in terms of their high voltage tracking resistance, insulation strength, breakdown voltage and strength, and weatherability effects afforded by the nanocomposite fillers.

Taxi trajectory data based fast-charging facility planning for urban electric taxi systems

This study develops a taxi trajectory data based fast-charging facility planning model for an urban taxi system by considering battery degradation and vehicle heterogeneity in driving range. The developed model comprises three functional modules: (i) fast-charging location determination, (ii) fast-charging facility deployment (FCFD) and (iii) FCFD solution tuning. Under the FCFD module, charging demand prediction considering battery degradation and vehicle heterogeneity, charging demand allocation and charger configuration optimization are executed sequentially. The FCFD solution is tuned by an effective backward elimination method to find a more economic and practical planning solution where the minimal number of chargers at each station can be specified. A case study in Singapore is thoroughly conducted, and insightful policy implications are revealed: policy-makers could use the tuning mechanism to significantly save investment and reduce total waiting time for charging; overlooking battery degradation and vehicle heterogeneity will yield a biased electric taxi charging facility planning.

Extinguishment of cable fires at packaged transformer substations

Introduction. According to the statistical data, electrical fires account for the majority of all fire accidents. Hence, better fireproofing of fuel and energy facilities is a relevant issue. The article addresses electrical fire extinguishment using high-expansion foam. An extinguishment time analysis methodology, applicable to fire extinguishment using high-expansion foam, has been developed to validate these solutions. The purpose of this article is to calculate the dependence between the fire extinguishment time and the foam consumption rate. The research objectives are to 1) identify the principal values to be used in the calculations and the list of input data; 2) to identify the dependence between the extinguishment time and the foam consumption rate using packaged transformer substation 2BKTP (1,000 kVA) as an example. Calculation methodology. The calculation methodology is based on the material balance equation between the amount of foam, applied for firefighting purposes, and the amount of foam, destroyed as a result of its contact with the heated wire surface, which is the main fire load inside burning electrical facilities. Research results. The co-authors have calculated the fire suppression time using packaged transformer substation 2BKTP (1,000 kVA) as an example. Dependencies between fire extinguishment time, specific foam consumption rate, and foam application rate are identified. Conclusions. The co-authors have identified the main values, needed to simulate a fire extinguishing model. They have also shown optimal foam consumption and application rates and offered their assessment of the applicability of high-expansion foam to electrical fires.

Infrared Thermal Image-Based Sustainable Fault Detection for Electrical Facilities

Faults in electrical facilities may cause severe damages, such as the electrocution of maintenance personnel, which could be fatal, or a power outage. To detect electrical faults safely, electricians disconnect the power or use heavy equipment during the procedure, thereby interrupting the power supply and wasting time and money. Therefore, detecting faults with remote approaches has become important in the sustainable maintenance of electrical facilities. With technological advances, methodologies for machine diagnostics have evolved from manual procedures to vibration-based signal analysis. Although vibration-based prognostics have shown fine results, various limitations remain, such as the necessity of direct contact, inability to detect heat deterioration, contamination with noise signals, and high computation costs. For sustainable and reliable operation, an infrared thermal (IRT) image detection method is proposed in this work. The IRT image technique is used in various engineering fields for diagnosis because of its non-contact, safe, and highly reliable heat detection technology. To explore the possibility of using the IRT image-based fault detection approach, object detection algorithms (Faster R-CNN; Faster Region-based Convolutional Neural Network, YOLOv3; You Only Look Once version 3) are trained using 16,843 IRT images from power distribution facilities. A thermal camera expert from Korea Hydro & Nuclear Power Corporation (KHNP) takes pictures of the facilities regarding various conditions, such as the background of the image, surface status of the objects, and weather conditions. The detected objects are diagnosed through a thermal intensity area analysis (TIAA). The faster R-CNN approach shows better accuracy, with a 63.9% mean average precision (mAP) compared with a 49.4% mAP for YOLOv3. Hence, in this study, the Faster R-CNN model is selected for remote fault detection in electrical facilities.

A novel method to correct temperature problems revealed by infrared thermography in electrical substations

The need to monitor and know the state of electrical facilities and their associated equipment has become of crucial importance to ensure the continuity of electrical power supply. To this end, scientific advances result in new measuring instruments that allow diagnosing the state of electrical equipment and thus preventing failures. Infrared thermography is one of the most used methods in predictive maintenance of electrical facilities in high, medium, and low voltage. Its application in electrical substations is especially relevant due to the key role of these facilities in the power supply chain of most of customers. Its low cost, rapid implementation, and the effectiveness of the results obtained make it possible to perform thermography diagnosis several times a year if necessary. However, at the moment of taking thermography images, the electrical facility may not be subject to the maximum electrical current that can circulate through it, and, consequently, the results of the diagnosis may be erroneous since the temperature reached is not the maximum, i.e., a detected hot spot that is determined as non-problematic can become so in the nominal conditions of the facility. The need to extrapolate the results obtained according to certain current to the situation where the maximum current circulates is thus evident. In this paper, a formula is proposed to extrapolate the temperature obtained with certain current to the temperature that should be reached with higher currents, closer to the maximum values of the facility. The proposal is based on experimental data obtained from laboratory thermography tests and it was successfully used in the field.

Peculiarities of the nature of intentional non-payment for energy loss cost at electrical grid facilities

The research subject is theoretical and practical developments of the need for legislative regulation of a legal prohibition of intentional non-payment for energy loss cost at electrical grid facilities. The research object is social relations ensuring legal protection against electrical energy misuse by electrical grid facilities. The authors study the distinction between  the non-payment for actual energy loss cost and the similar civil wrongs. Special attention is given to subjective and objective signs which should be established in order to classify the offense as the illegal use of electric energy which has caused property damage to the energy supplier. The research methodology is based on the general dialectical, logicalm formal-legal, hermeneutical, and statistical research methods. The scientific novelty of the research consists in the fact that the imposition of criminal responsibility for deliberate non-payment for electric energy loss at electrical grid facilities is an area of concern in a current law enforcement practice as it requires the establishment of an objective and subjective parties to an offence and its distinguishing from other civil wrongs. The absence of a common strategy of imposition of criminal liability on those responsible can cause the growth of the number of illegal and unreasonable decisions during a pre-investigation review, and therefore, the growth of equivalent crimes. It explains the need for the optimization of legal measures by means of amending the current Resolution of the Supreme Court Plenum, or the article 165 of the Criminal Court of the Russian Federation with a new regulation on illegal use of electric energy. 

Development of a method for using AI systems for assessing cyber threats to electric power facilities

Modern trends in the development of the electric power industry declare the widespread use of information and communication technologies and digital services to improve the operation of relay protection and automation (RPA) subsystems, ICS, WAMS, etc. However, this is associated with an increase in the number of cyber threats and risks of disrupting the stable functioning of electric power facilities due to destructive information influences. The report presents the results of the synthesis of a hybrid method for modeling cyber threats with possible cyber-physical consequences and the development of a demonstration prototype of an expert system that implements the method.

Neural network model of decision making in electric power facilities under conditions of uncertainty

The article is devoted to the issue of creating a mathematical model of the problem of making management decisions in electric power facilities based on modern intelligent technologies, which makes it possible to take into account the influence of various factors on the operating modes of the power system. A systematic approach to describing processes in the mathematical language of the theory of fuzzy sets is proposed. To solve the problem of controlling the operating modes of the power system, a neurofuzzy network has been developed that combines the algorithms of Takagi-Sugeno fuzzy inference, as well as a recurrent neural network. An adaptive learning algorithm based on the Frechet method is proposed for training a neural network. The analysis of the efficiency of the fuzzy control model under the conditions of various modes of functioning of the local power system is carried out.

Development of Safe Two-Store Minimalist Type of Residential House Against COVID-19, Based on Local Wisdom of the Bugis, and Environmental Insight

This study intends to explore the values of local wisdom of the Bugis tribe, in building houses, which are associated with the current situation of the COVID-19 Pandemic. The purpose of this study was to find: (1) the development of a minimalist, two-story type residential design that is safe against COVID-19, based on local wisdom of the Bugis Tribe, and environmentally friendly, (2) steps for implementing the design, and (3) supporting factors and impediments to design development. Research locations in the Districts: Bone, Soppeng, and Wajo. The research sample was 300 people, selected by purposive sampling. The research variables are: (1) visible design development, (2) design implementation steps, and (3) supporting factors and inhibiting design development implementation. Data analysis technique, is a qualitative descriptive analysis. After concluding the analysis, the next step is to develop the design. The results of the research on the design development of a minimalist, two-story type residential house that are safe against COVID-19, based on local wisdom of the Bugis Tribe, and environmentally friendly, show that: 1) Front view seen from: (a) the position of the sun facing east, (b) contour the ground is facing a higher and flatter direction, (c) the position of the road facing the main highway, (d) the slope of the roof is 25-30 degrees, and (4) the shape of the roof, gable and shield. 2) Steps for implementing the design: (a) conducting socialization, (b) providing explanations about healthy houses and local wisdom of the Bugis Tribe, and (c) collaborating with relevant stakeholders. 3) Factors supporting the implementation of the design are: (a) affordable selling prices for low-income earners, (b) available land for house development and green open land, (c) house designs are classified as healthy, and (d) available roads, water facilities clean, and electric facilities. The inhibiting factors are: (a) the Bugis forget their local wisdom, (b) the planning consultants and developers do not understand the local wisdom of the Bugis.

Application of battery energy storage systems in industrial facilities

For any facility, reliability and availability of power are key. Traditional gas- or diesel-driven power generation designs for facilities rely on generated spinning reserve to achieve power system stability and availability for defined operational scenarios and expected transients. Spinning reserve is extra generating capacity that is usually introduced by running additional power generator(s). Battery energy storage systems (BESSs) as energy storage units provide for a virtual spinning reserve in a hot standby arrangement to achieve the same effect for a set period during operating scenarios and transient events. Use of BESS technology is becoming more frequent within electrical network systems, remote sites and industrial facilities on the back of improved battery technology. This lends itself to better BESS reliability, effectiveness and lower associated cost to procure and install. Many of Clough’s projects are remote and islanded where they need to be self-sufficient, generating and distributing their own power needs. BESS units are scalable energy storage systems that can be used as a part of power generation solutions for facilities installed onshore or offshore. In addition to supplementing the primary generation on a facility as static storage units, BESS units offer benefits such as reduced emissions on facilities by not burning fossil fuels to achieve spinning reserve; they also allow for power management of generation systems, store any excess power from primary generators, allow for integration of renewables, offer constructability benefits and reduced operational/maintenance costs. The commercial and environmental benefits of BESS units are key drivers in Clough’s decision to embrace their use on future projects.

Half division two-dimensional method for simple sinusoidal quantities parameters accurate measurement

Several variants of half division two-dimensional method are proposed, which is the basis of a fundamentally new approach for constructing measuring instruments for sinusoidal or periodic electrical quantities. These measuring instruments are used in the diagnosis of electric power facilities. The most general variant, called midpoint method, is considered. The proposed midpoint method allows you to measure much smaller than using widespread methods, alternating currents or voltages, especially when changing the amplitude of the measured signal in very wide ranges, by 1–2 orders of magnitude. It is shown that using the midpoint method it is possible to suppress sinusoidal or periodic interference in the measuring path, in particular, to measure small alternating current when sinusoidal or periodic interference is 1–2 orders of magnitude higher than the useful signal. Based on the results of comparative tests, it was found that the current measuring device implementing the midpoint method is an order of magnitude more sensitive than the currently used high-precision measuring instruments.

Aspects of the concept of cyber-protected objects of a digital electrical network with elements of Zero Trust Architecture in Russia

Modern trends in the development of the electric power industry declare the widespread use of information and communication technologies and digital services to improve the operation of relay protection and automation (RPA) subsystems, Industrial Control Systems (ICS), commercial electricity metering systems, etc. However, it is associated with an increase in the number of cyber threats and risks of disrupting the stable functioning of electric power facilities due to destructive information influences. The report presents aspects of a holistic concept of building cyber-protected digital substations with elements of Zero Trust Architecture. Based on the results of the theoretical investigation the authors assume the possibility of technical testing of the proposed approaches to build a cyber-protected digital substation as a part of the emerging Research and Development (R&D) programs for the practical implementation of the zero-trust policy.