Electrical Distribution Networks Research Articles

Estimating primary substation boundaries and the value of mapping Great Britain's electrical network infrastructure

Localised data aggregation in many countries including Great Britain (GB) is typically performed at a geographical level with polygon boundaries that have a robust and trusted governance system in place. This means there is confidence in a process to create a set of polygons that have unique identifiers coupled to geographical areas, and the ability to have these updated through a defined code of practice. Examples found across many countries are in the delivery of post, such as post codes and zip codes, and of the definition of census areas and municipal boundaries. The confidence in these boundaries allows different data to be aggregated by third parties, which itself provides greater amounts of data over comparable geographical areas to enhance wider analysis and decision making. As helpful as these polygons are for certain types of analyses, they are not specifically defined for energy systems analysis. Here we combine publicly available datasets published from the six regional electricity Distribution Network Operators of GB to produce a new geospatial dataset with 4436 unique polygons defining the areas served by electrical primary substations. An example demonstrating the value of these polygons is given to link these polygons with postcode level open government datasets on domestic energy consumption (2015–2020) from the Department of Energy Security and Net Zero (DESNZ). The resulting new data reflects energy statistics aggregated to the geographical areas served by each primary electrical substation across Great Britain. The significant value of the generated data is demonstrated by the quantification of the domestic annual heating demand presently met by natural gas across different primary substation areas which varies from an average of 5100 kWh to 28,900 kWh per property. This highlights how the rate of electrical capacity expansion will have to differ by geography under an electrified heating scenario. Therefore, we believe there is a compelling argument for all countries to set up processes to create and update polygons that have a meaningful relationship to energy systems. This would allow more accurate energy systems analysis to be performed, ultimately leading to an accelerated or potentially lower cost transition to a net zero world.

Study of the Management of the Electrical Energy Production and Distribution System Within the National School of Teachers of Mamou, Guinea

With the energy transition, marked essentially by the mass integration of energy production based on renewable resources, the missions and challenges of electrical energy distribution networks are evolving. This study is part of this dynamic, its objective is the study of the management of the production and distribution system of electrical energy within the National School of Teachers of Mamou. It emerges from this study that the supply of electrical energy to the National School of Teachers of Mamou is ensured by a hybrid system of three power sources: photovoltaic solar fields, Generator Group and Electricity of Guinea. The current electrical energy requirements of the Mamou NST are 40 kW. The total power of the installed photovoltaic solar fields is 70 kWp; the Generator used has a power of 10 kVA; the site’s Electricity of Guinea network is made up of transformers, cabin substations and protective equipment. The electricity distribution network is characterized by: Four (4) 250 A circuit breakers; a 32 A circuit breaker for the departure of lamps, sockets and fans; a 10 A circuit breaker for the lamps; a 10 A circuit breaker for the fans; a 16 A circuit breaker for the sockets and an 800 A mechanical inverter. The study shows that the power of photovoltaic solar fields is largely sufficient to cover the current electrical energy needs of the National School of Teachers of Mamou.

АНАЛІЗ ПОКАЗНИКІВ ЯКОСТІ ПОСЛУГ ПОСТАЧАННЯ ЕЛЕКТРИЧНОЇ ЕНЕРГІЇ

The object of the study is the processes in distribution electric networks and their influence on technical and economic characteristics aimed at achieving the main indicators of reliability, which is characterized by the continuity of electricity supply, namely, indicators of the quality of services: the index of the average duration of long interruptions and the index of the average frequency of long interruptions ( SAIDI, SAIFI), as well as compliance with the guaranteed quality standards of electric energy supply services, which are established by the Resolution of the NCRECP. The problem to be solved is a set of factors aimed at reducing the index of the average duration of long interruptions and the index of the average frequency of long interruptions (SAIDI, SAIFI), taking into account and applying effective measures of stimulating tariff formation (Rab - tariff) aimed at providing quality services to consumers of electric energy in accordance with the guaranteed standards established by the Resolution of the NCRECP. The analysis of the main indicators of the quality of SAIDI and SAIFI services for the period from 01.01.2022 to 03.31.2022 was carried out on the example of the operator of the distribution system JSC "Kharkivoblenergo". The impact of natural and unnatural factors on the formation of these indicators is analyzed, taking into account force majeure circumstances and military aggression on the territory of the Kharkiv region. The changes in the quality indicators of SAIDI and SAIFI services and their compliance with the normative values established by the NCRECP were analyzed. The conducted analysis of SAIDI and SAIFI service quality indicators allows us to state that achieving the target values of electricity supply continuity indicators is a fundamental factor for improving the quality of electricity supply services to consumers. The provision of the necessary guaranteed quality standards for the supply of electric energy to consumers is substantiated taking into account the stimulating tariff formation (Rab - tariff). It is shown that the introduction and development of stimulating tariff formation lays a reliable foundation for a strong and competitive Ukraine on the territory of the European Union and introduces dynamic development for a strong and independent Ukrainian economy. Ref. 19, figure, table.

СКЛАДОВІ ПОТУЖНОСТІ ТИРИСТОРНОГО РЕГУЛЯТОРА НАПРУГИ З АКТИВНИМ НАВАНТАЖЕННЯМ

A study of the power balance of the semiconductor voltage regulator on an active load with phase control by two-operation thyristors was carried out. The suitability of its use for simultaneous obtaining of the reactive power resource for distribution electric networks has been confirmed. According to the concept of intelligent electrical networks, such devices belong to the class of flexible alternating current transmission systems, and they can be the basis for building virtual energy sources. The power components for individual components of the regulator, including the thyristor block, were studied. The spectral method of describing currents and voltages at the regulator sections is applied. The obtained results of theoretical studies were confirmed by an example with numerical calculations, which made it possible to clarify the physical essence of energy transformations during voltage regulation. Bibl. 8, fig. 3.

Reducing non-technical losses in electricity distribution networks: Leveraging explainable AI and three lines of defence model to manage operational staff-related factors

This study presents a multidisciplinary approach involving Explainable Artificial Intelligence (ExAI) and operational risk management to reduce Non-Technical Losses (NTL) in electricity distribution. It empirically explores how the activities of employees of utility companies contribute to NTL, a phenomenon often overlooked in existing empirical research. An ensemble classification algorithm is used to analyse utility operations data, and the SHAP explainability technique establishes the predictive significance of staff activities for NTL. Subsequently, these staff activities are mapped into risk cells using the BASEL II and III operational risk definitions, and the Three Lines of Defence (3LoD) model is developed for optimizing electricity distribution. The paper makes three original contributions to the literature: first, it empirically links staff operations to NTL; second, it maps NTL causes to Basel II/III operational risk categories; and finally, to the best of the authors’ knowledge, it is the first study to use the 3LoD model for electricity distribution optimization.

Development of a Maintenance System for Low Voltage Electricity Distribution Networks

This research focuses on important efforts to ensure the availability and reliability of electricity supply through the design and implementation of effective systems for monitoring and maintaining low voltage electricity distribution networks. The methods used in this research include analysis of maintenance needs, development of software for network monitoring, and integration of sensor technology for early detection of disturbances. The developed system aims to increase maintenance efficiency by providing real-time information about network conditions, enabling preventive action before disruptions occur. In addition, this system is also designed to reduce downtime and maintenance costs, as well as increase the reliability of electricity supply for customers. The research results show that implementing advanced sensor technology and monitoring software can significantly improve response to disruptions and minimize the impact on customer service. Thus, this system not only increases operational efficiency but also provides long-term benefits in maintaining the stability and reliability of electricity supply.

A Vehicle-to-Grid planning framework incorporating electric vehicle user equilibrium and distribution network flexibility enhancement

The rapid surge in electric vehicle (EV) adoption, coupled with advancements in charging technologies, emphasizes the critical necessity for expanding EV recharging infrastructure. Simultaneously, the Distribution Network (DN) encounters escalating challenges in meeting charging demand during peak traffic periods. Consequently, there is a mounting demand for the deployment of innovative Vehicle-to-Grid (V2G) technologies to augment the DN’s flexibility in power dispatch and alleviate travel costs for EV users. Hence, this paper proposes an EV-user-equilibrium-(UE)-constrained V2G planning framework that enhances flexibility in the DN. The framework aims to ascertain the optimal placement and capacity of EV charging stations (EVCSs) and V2G charging piles within the Transportation Network (TN). It takes into account the equilibrium condition stemming from competitive EV charging and routing behaviors alongside the optimal expansion of DN energy resources to accommodate the electricity supplied by the V2G piles. This study commences by analyzing EV drivers’ travel decisions, considering the influence of charging and V2G pile locations and sizes. Subsequently, we tackle the Traffic Assignment Problem with User Equilibrium (TAP-UE) model to characterize the steady-state traffic flow distribution of EVs. Following this, we formulate the optimization model for the Coordinated Power and Transportation Network (CPTN), which encompasses the optimal expansion of DN facilities and traffic flow regulation under UE conditions. To mitigate the computational complexity associated with the V2G planning model, we introduce a series of linearization methods to obtain a manageable Mixed-Integer Linear Programming (MILP) solution. Finally, to validate the efficacy of our proposed planning framework, we apply it to two test systems, including a real-world case study. Through these case studies, we explore the necessity and potential benefits of V2G technologies.

A Review on Electric Vehicles for Holistic Robust Integration in Cities: History, Legislation, Meta-Analysis of Technology and Grid Impact

Electric vehicle technology is transitioning from mobility based on fossil fuel combustion to one based on vehicle electrification, in which the primary energy is increasingly renewable, and the generation of pollutants and CO2 emissions is being reduced. This paper provides a tour of the key aspects of these systems, reviewing their most important historical, legislative, and grid impact topics. For this purpose, a literature review of publications up to 2022 is conducted. The last decade is the subject of a deeper analysis, shedding light on the essential characteristics of this technology and fundamentally focusing on its integration into electrical distribution networks. This work is carried out based on a review of a selection of articles written by authors worldwide who have researched these topics. We ordered and analyzed the temporal evolution of the defined categories, obtaining their research line direction. A meta-analysis of grid impact was also carried out, prompting clear conclusions about the state of the art and potential future works.

Optimal allocation of EV charging station and capacitors considering reliability using a hybrid optimization approach

This paper proposes a novel approach for strategically placing EV charging stations (EVCS) and capacitors within electrical distribution networks (EDN) to mitigate issues arising from the widespread adoption of Electric Vehicles (EVs). The goal is to maximize the net present value (NPV) by reducing energy losses and minimizing system interruption costs while ensuring reliability. To achieve this, the paper introduces a hybrid optimization technique called HGP_CS, which combines Grey Wolf Optimization (GWO), Particle Swarm Optimization (PSO), and Cuckoo Search optimization methods. By employing various compensation coefficients to assess failure rates and identify strategies for enhancing NPV, the approach aims to optimize the placement of EVCS and capacitors within the EDN. Validation is carried out in IEEE 33-bus and 118-bus systems to demonstrate the performance of the proposed approach. It is found that the proposed approach, compared to the base case, reduced the energy loss cost by 34.19% and 31.57% and also the Expected Interruption Costs (EIC) by 17.26% and 13.41%, for IEEE 33-bus and 118-bus system, respectively. Additionally, the proposed method is economically beneficial as it can attain higher profits. In IEEE 33- bus and 118 bus systems, the annual net profit using the proposed approach is 36,805 $/year and 271,670.72 $/year, respectively. Thus, the proposed technique enhances the overall system performance and significantly boosts profitability, making it a compelling choice for optimizing the placement of charging stations and reactive power sources in networks.

A dynamic reference voltage adjustment strategy for Open-UPQC to increase hosting capacity of electrical distribution networks

Future electrical grids, particularly the distribution networks, may face more severe voltage rises/drops, and in general, more power quality problems in the presence of new loads such as electric vehicle chargers and renewable energy generation units like photovoltaic systems. This necessitates investing in additional high-cost infrastructure to increase the capability of the feeder in hosting higher levels of loads and generation units while the existing capacity is not utilized effectively. In the stated condition, effective voltage stabilization strategies in electrical distribution networks can contribute to hosting capacity improvement and the better utilization of the existing infrastructure. Accordingly, in this paper, the application of Open-UPQC in voltage profile improvement and hosting capacity enhancement is evaluated in low-voltage distribution networks. Furthermore, a dynamic reference voltage adjustment strategy is applied to the device to improve its capabilities in power quality improvement and hosting capacity enhancement. Simulation studies have been implemented to evaluate the capability of Open-UPQC either with static reference voltage or the dynamically-adjusted one in low-voltage networks with real measured data while different cases are assessed regarding the topology and the length of the feeder. The simulation results approved the capability of Open-UPQC especially with the dynamic reference voltage in hosting capacity enhancement while providing the highest level of voltage profile improvement among all the assessed custom power devices in the studied low-voltage networks.

Modeling Interdependent Infrastructure System Vulnerability with Imprecise Information Using Two Fuzzy Inference Systems

Infrastructure systems play important roles in economic development and the social quality of life. Interdependencies exist between infrastructure systems: a functional disruption in one system can affect dependent systems, thereby escalating the impacts. It is vital to properly model interdependencies to understand the full impacts of disruptive events on infrastructure systems. Quantitative data on infrastructure interdependency is often difficult to obtain or unavailable for a variety of reasons. To overcome quantitative data scarcity issues, qualitative subject expert knowledge has been used in interdependency analysis, primarily in the form of linguistic responses. Linguistic data is susceptible to uncertainties arising from variations in intended meanings, which may yield inaccurate results. This paper proposes a framework to address this problem using two fuzzy inference systems to model event-specific, network-wide infrastructure failures. The first fuzzy inference system models the damage induced by interdependencies using verbal descriptions. The second fuzzy inference system accounts for synergistic, compounding effects of multiple incidences of indirect damage caused by interdependencies. A case study is conducted to demonstrate the applicability of the proposed methodology using electric and gas distribution networks in the United Kingdom. Sensitivity analyses are performed to show the flexibility of the fuzzy inference systems. The results show that the proposed method can model the interdependency and vulnerability of infrastructure systems using fuzzy inference systems to handle imprecise input. The proposed framework may assist practitioners in better understanding the interdependency and vulnerability of infrastructure systems, and in making more informed decisions to reduce losses resulting from disruptive events.

APPLICATION OF THE FLOYD-WARSHALL ALGORITHM TO OPTIMIZE ELECTRICITY DISTRIBUTION IN THE CITY OF CIMAHI

Efficiency in the use of electricity is a necessity for the sustainability of a better life. Almost all human activities utilize electrical energy, such as household appliances, industry, and even vehicles. This research contains the efficiency of electricity use in a housing by applying graph theory in optimizing the electricity distribution network system. The purpose of this study is to optimize the electricity distribution network system in the residential area of Kota Mas Cimahi, so that the best network model is obtained. Network data and information were obtained from PT. PLN UP3 Cimahi, West Java. The method used is to determine the minimum spanning tree in the electricity distribution network model by applying the Floyd-Wish algorithm. The initial model of the power grid was constructed by data on the position of substations and power poles, the number of power poles, and the length of the power cables connecting the poles. The data used is data on a line from several electricity distribution lines in this housing. The result of the minimum cable length on this line is 349 meters. The results of this study are expected to provide alternative solutions and additional information in planning and structuring the power grid optimally. Furthermore, the results of this research can also be used by PLN in order to support the government's program towards the efficiency of using electrical energy to serve the community because they get electricity services faster and cheaper

Use of a Decision Tree to Define Transformer Oil Contamination from On-Load Tap-Changer Gases to Ensure Power Quality in the Grid

Power transformers are one of the most important and critical assets in the electricity distribution and transmission network. Power quality (PQ) can be disturbed when a power transformer is brought into or out of service, so it is very important to be sure of the reason for this action. Dissolved gas analysis (DGA) in oil can be used to diagnose the condition of transformer insulation. There may be situations where the DGA results indicate the presence of a serious fault which would lead to the transformer being taken out of service, when in fact the high gas concentrations are due to the leakage into the main oil tank of gases generated in the on-load tap-changer (OLTC) during normal operation. In previous work, using machine learning techniques and a distribution system operator's DGA database, a decision tree (DT) was developed to identify oil contamination from OLTC gases. In this work, the developed DT is applied to a new DGA database to identify contaminated transformers and test its accuracy. A total of 1161 DGA results from 95 transformers with OLTC were used, giving an initial DT accuracy of 83.13% when all samples were analysed and 85.26% when the last DGA result from each transformer was used.

Impact of Fraxinus snag fall on electric distribution and infrastructure stability: An empirical analysis

With increasing climate variability and the movement of exotic pests and diseases, the rate of forest mortality has become an issue of global concern. Emerald Ash Borer (EAB), as one such pest, is causing the mass mortality of ash trees, Fraxinus spp., thus leading to an ongoing surge in the number of snags across North America. Snags are dead-standing trees that pose an extant threat to nearby infrastructure and buildings. In this article, we evaluate the impacts which snags pose to electrical distribution infrastructure. New Jersey, a state with a high degree of urbanization, has an extensive electric grid located in forested areas. New Jersey is currently in the process of upgrading the electric distribution network, which will increase the height of electric distribution lines to increase resiliency and potential capacity. This article demonstrates a yearly risk assessment methodology for Fraxinus snags using an integrated GIS, differential equation, and applied regression model framework under two distribution network parameterizations. The framework is applied to three northern New Jersey counties (Warren, Sussex, and Morris), which are managed by one utility, New Jersey Central Power and Light, and which are home to most of New Jersey’s Fraxinus trees.

Causes of accidents in electrical distribution networks (using the example of the branch of PJSC Rossetti Volga – Saratov Distribution Networks)

The article is a continuation of a series of studies dedicated to the analysis of power transmission through distribution electric networks of PJSC ROSSETI. The presented material analyzes the functioning of the electrical networks of the branch of PJSC Rosseti Volga – Saratov Distribution Networks. An analytical assessment of the electric energy transport through distribution electric networks was carried out for the period 2018–2022. The structure of the company is considered, the structural characteristics of the main elements of the studied electrical networks are given, and the number of emergencies that occurred during the study period is estimated. A quantitative assessment of the magnitude of the electric energy undersupply caused by power supply interruptions is given. The classification of failures according to the degree of the intensity of undersupply was carried out and a quantitative assessment of each group of failures according to their intensity was made. The influence of the seasonal component on the number of emergencies during the study period is considered. Based on the data from 2022–2023, the analysis of the main causes of damage to the elements of electrical networks was carried out. The classification of failures by groups of failure causes is made, their main characteristics for this period are considered. The percentage ratio of the number of failures number for the most characteristic reasons to the total number of outages during the study period has been established. The information published in the open press was used as the source data. General scientific methods as well as numerical methods of analysis were used in the research. MATLAB graphics editor technologies were used to visualize the obtained analysis results. The results obtained may be of interest to the managers of power grid companies, as well as researchers and engineers engaged in research in the field of reliability of power supply.

Advanced control of double stage grid-tied three phase photovoltaic systems with shunt active power filter

This paper explores the challenges associated with the control of a two-stage three-phase electrical grid connected to a photovoltaic (PV) system. The objectives encompass: i) maximizing the available PV power, ii) controlling the DC-link voltage to a predetermined setpoint, and iii) considering that power quality has become an important measure in a distribution electrical network where different loads are connected, the third objective will mainly focus on ensuring power factor correction (PFC). To achieve these objectives, two loops of nonlinear controller are developed. In the outer loop, the duty cycle of a boost converter is controlled using a hybrid technique of backstepping technique and the perturb & observe (P&O) algorithm. In addition, the inner loop employs a hybrid automaton approach to tackle the challenges of a three-phase shunt active power filter (SAPF). The results have been verified through numerical simulation using MATLAB/Simulink power systems environment.

Power and voltage stability analysis of electric vehicle distribution network considering virtual power plants

Power and voltage stability analysis of electric vehicle distribution network considering virtual power plants

On the Improvement of the Reliability of the Electrical Distribution Networks by Using Smart Electric-supply Restoration Algorithm

On the Improvement of the Reliability of the Electrical Distribution Networks by Using Smart Electric-supply Restoration Algorithm

On the Improvement of the Reliability of the Electrical Distribution Networks by Using Smart Electric-supply Restoration Algorithm

On the Improvement of the Reliability of the Electrical Distribution Networks by Using Smart Electric-supply Restoration Algorithm

Load restoration of electricity distribution systems using a novel two‐stage method

AbstractThis paper proposes a new comprehensive load restoration (LR) method for electrical distribution networks. Since two main technologies of switching equipment are there in the modern distribution networks, namely manual switches (MSs) and remote‐controlled switches (RCSs), this article has benefited from this concept effectively. A two‐stage algorithm that provides the system operators with the ability to recover part of the loads in the shortest possible time by RCSs is proposed. After this step, the remaining loads will be restored by a combination of MSs and RCSs. The other strength of this algorithm is to provide accurate and practical solutions so that the sequence of switching actions is clearly defined. Also, using an innovative index called expected weighted energy not supplied as the objective function of the main problem will ensure the operators recover the maximum amount of load in the shortest time possible. This novel method was applied on a sample standard IEEE distribution test network. The simulation results proved the effectiveness of this proposed method.