Distribution System Research Articles

Reliability Assessment of Power Distribution Cyber–Physical Systems Considering the Impact of Wireless Access Networks

With the rapid increase in the number of various terminal devices in distribution systems, the important impact of communication networks on power supply reliability in cyber–physical distribution systems (CPDSs) is becoming increasingly prominent. The traditional wired communication method makes it difficult to meet the demand in some scenarios due to high cost and construction difficulty. For this reason, this study evaluated the reliability of power distribution cyber–physical systems, considering fifth-generation (5G) mobile communication technology wireless access conditions. First, a reliability model of a communication channel in a 5G communication network was established, and the indirect impact of information system failure on the power distribution system was analyzed. Secondly, a reliability assessment method based on the improved least path method was devised by combining switch action failure, self-healing processing, and load transfer. The simulation results show that 5G communication technology has significant advantages in improving system reliability, and the proposed method is closer to the development direction of future power distribution systems, which provides an effective reference basis for the optimized operation of power distribution cyber–physical systems.

Legionella community dynamics in a drinking water distribution system: Impact of residual chlorine depletion

This study investigated the occurrence of Legionella spp. in a chlorinated drinking water distribution system (DWDS), focusing on their community compositions and association with physicochemical water quality. Water samples were collected throughout the DWDS, covering from the treated water reservoir to distal ends. Although Legionella spp. genes were not detected at the reservoir, their abundance dramatically increased along the distribution network, reaching up to 4.4 log copies/L at distal sites. The Legionella communities were further characterized by high-throughput amplicon sequencing targeting the genus-specific 16S rRNA gene. The results revealed a diverse Legionella community, including amplicon sequence variants with high similarity (> 99 %) to potentially pathogenic species such as L. drozanskii and L. pneumophila, albeit at low levels. Moreover, Legionella community diversity increased significantly along the distribution system, leading to distinct community compositions at distal sites. Importantly, decay of residual chlorine concentration was identified as a key factor both in increasing the Legionella gene levels and shaping the community structure. Overall, this study underscores the importance of preventing pipe corrosion and maintaining adequate disinfectant residuals to minimize Legionella regrowth in DWDS.

Three-Level Double LLC Resonant Converter with Ripple-Free Input Current for DC Microgrid Application

DC distribution systems have garnered interest in recent years due to their advantages over AC distribution systems, such as their high power conversion efficiency and lack of harmonic issues. An isolated DC-DC converter with low-input noise, high efficiency, and high-power density is required for DC microgrids within DC distribution systems. Although existing DC to DC converters have high efficiency and high power density, they still have input noise problems due to pulsating input currents. Thus, a large input filter should be inserted, which increases the cost and degrades the power density. In this study, a novel three-level double LLC resonant converter with zero-input-current ripple is presented for DC microgrid application with a high-voltage DC bus. The input-current ripple of the proposed converter theoretically decreases to zero without adding large input filters. Moreover, the voltage stress on each main switch is only half of the input voltage when using the modified three-level structure, which enables the use of low-voltage-rated power switches for high-voltage input applications. In addition, all the primary switches and secondary diodes are softly switched over a wide input voltage range. The experimental results of the prototype are presented to verify the performance of the proposed converter.

How Has Cuisine Identity Sustained the Fancy Food Markets Throughout the Worlds Food Distribution Systems?

How Has Cuisine Identity Sustained the Fancy Food Markets Throughout the Worlds Food Distribution Systems?

Development of a Machine-learning-based Framework to Assess the Performance of Water Distribution Systems

Recent statistics indicate that the national water supply coverage is approximately 99%, reflecting a high level of service. However, the aging infrastructure continues to cause issues such as pipe failures and water quality concerns, creating operational difficulties. To solve these issues, performance assessments are used to quantitatively evaluate the system conditions and ensure effective maintenance. In Korea, these assessments are based on a scoring system that combines direct and indirect assessments. However, direct assessment of all pipes is limited by cost and time constraints. To address this issue, a deep neural network is used to assess the aging of water distribution systems. This study develops a framework to estimate direct results from indirect data by analyzing the correlation between indirect and direct assessments. Additionally, data augmentation is considered to compensate for the lack of training data in direct assessments, improve the reliability of performance assessments, and support better prioritization in system maintenance.

Analysis of cooling load calculations using AHU in swimming pools (indoor pools)

AC or Air Conditioner is one of the most widely used mechanical devices in Indonesia. A machine device that functions as an air conditioner so that the indoor air temperature is comfortable, healthy, and has the humidity required by the occupants. Air freshening systems or ACs are increasingly becoming a necessity for urban communities, whether in homes, office buildings, apartments, hotels, swimming pools, hospitals, and even in lecture rooms. The indoor swimming pool measuring 40 x 11 x 3.5 m is located in the apartment So it is uncomfortable for swimmers. Thus, it is necessary to design using an AC system so that the temperature in the swimming pool is cool and comfortable for swimmers. The planning methodology starts by determining data on the indoor swimming pool in apartment AC used. From the analysis results, the cooling load was obtained at 411.5 kW, including a sensible load of 397.66 kW and a Latin load of 13.85 kW, the refrigerant used by the engine was R134a, the compressor power was 81 HP, while the COP was 6.8. So that the indoor air is evenly distributed comfortably, the indoor cold air distribution system uses an AHU (Air Handling Unit) system, capacity of 1900 m3/hour. 2 AHU Units, Blower Power 3 kW

Analysis of the Electric Power Distribution System Service Reliability Index at PLN Lancang Garam

The level of electrical energy demand in an area reflects the welfare of that community. The greater the use of electrical energy, the higher the community's standard of living, followed by the public's critical attitude towards everything that happens and influences lives, including electricity services. Generally, a network's reliability level can be seen from the size of the SAIDI and SAIFI values on the PLN (state electricity company) side. The calculation and reliability analysis results of the Lhokseumawe ULP above show that the total SAIFI index value is 2.68 times/year. The SAIFI Rayon Lhokseumawe reliability index is categorized as reliable because its value does not exceed the standard set by PLN in SPLN 68-2 of 1986, namely 3.2 times/year. The total value of the SAIDI index is 45.30 hours/year. The Lhokseumawe Rayon SAIDI reliability index is categorized as unreliable because its value exceeds the standard set by PLN in SPLN 68-2 of 1986, namely 21 hours/year. There are certainly differences in infrastructure, electrical equipment, and number of customers in 1986 compared to current years; this has a different influence on electricity reliability values such as SAIDI and SAIFI.

Analysis of Micro Business Marketing Strategy in Facing Competition

This study is motivated by the challenges faced in the development of micro-enterprises at Bukit Sion Market, largely due to the high level of competition. Many businesses struggle to determine appropriate financing models and product offerings, as the market is saturated with similar products offered by competitors. The objective of this research is to analyze the marketing strategies employed by micro-enterprises and identify the obstacles they face in dealing with competition at Bukit Sion Market, Lahomi District. The research employs a descriptive qualitative method. The findings reveal that all food stalls adopt marketing strategies that include market selection, product planning, pricing, distribution systems, and marketing communication. Effective marketing strategies, such as offering discounts, special promotions, or hosting promotional events, have been shown to significantly boost sales. However, the food stalls encounter several challenges, including intensified competition due to the emergence of similar businesses offering comparable products, a lack of product innovation and promotion, fluctuations in raw material prices, as well as issues with product quality consistency, customer service, and overall customer experience.

Sistem Pendistribusian Zakat oleh Baznas Kabupaten Langkat Menurut Undang-undang No. 23 Tahun 2011 tentang Pengelolaan Zakat: Studi Kasus di Desa Karang Rejo, Kec. Stabat, Kab. Langkat

UU no. 23 of 2011 concerning zakat management as a complement to the previous law, namely law no. 38 of 1999. This law provides institutional strengthening in integrated zakat management into a unified integrated system. In turn, the National Amil Zakat Agency becomes the only institution holding zakat authority, and the Amil Zakat Institution as a partner in assisting the National Amil Zakat Agency, as well as government oversight as a regulator. The research aims to answer the problem of how the distribution of zakat according to zakat law no. 23 of 2011 in Kab. Langkat. How is the zakat distribution system by BAZNAS Langkat Regency in Karang Rejo Village. What are the factors causing the delays of the BAZNAS distribution system in Langkat Regency. What is the strategy of BAZNAS Langkat Regency to increase the collection and effectiveness in distributing zakat in Karang Rejo Village, Langkat Regency. This research is a qualitative research using a legal sociology approach. The types of data used in this study are primary data and secondary data, secondary data as initial data obtained from primary and secondary legal materials, then followed by primary data or field data obtained from documents and interviews with several Amil Agency officials Langkat District National Zakat. The results of the study show that the National Amil Zakat Agency in Langkat Regency has not run optimally in the distribution of zakat due to several obstacles, one of which is the lack of synergy with the local government in terms of regulations that have an impact on non-optimal distribution.

Karakteristik Breakdown Voltage Pada Dielektrik Minyak Mineral dan Minyak Ester Natural

The increasing demand for electrical energy, driven by population growth and industrial development, necessitates efficient and sustainable power distribution systems. Transformers, essential components of these systems, typically use mineral oil for insulation and cooling, despite its environmental drawbacks, such as high carbon emissions and non-biodegradability. In response, natural ester oils have emerged as eco-friendly alternatives. This study aimed to compare the dielectric breakdown voltage characteristics of mineral oil (Diala B) and natural ester oil (FR3) in transformer applications. The testing followed the IEC 60156 standard, focusing on transformers operating at 20 kV, with a minimum breakdown voltage threshold of 30 kV/2.5mm. Both treated and untreated samples were examined.The results indicated that FR3 ester oil exhibited superior dielectric properties, including higher breakdown voltage, flashpoint, and firepoint, as well as lower carbon emissions compared to mineral oil. These findings suggest that natural ester oil has significant potential as a sustainable replacement for mineral oil, particularly in applications where environmental and safety concerns are prioritized.The study recommends further long-term testing under operational conditions to confirm the performance and stability of ester oil in real-world transformer applications. These findings contribute to the growing body of research supporting the transition to more environmentally friendly transformer insulation materials, which could have broad implications for the power industry’s sustainability efforts

ANÁLISE SOBRE A INDÚSTRIA 4.0 NA DISTRIBUIÇÃO DE ENERGIA E O FUTURO DAS REDES INTELIGENTES

The technological evolution brought about by Industry 4.0 has significantly impacted several sectors, including the energy sector. The introduction of smart grids into the energy distribution system offers solutions to increase efficiency, integrate renewable sources, and reduce losses. These networks use technologies such as automation, big data, and the Internet of Things to modernize the way energy is managed and distributed. The overall objective of this research was to analyze the impact of Industry 4.0 on energy distribution, focusing on the implementation of smart grids in Brazil. To achieve this objective, the methodology adopted was a literature review with a qualitative approach, using articles published between 2020 and 2024, obtained from databases such as Lilacs, Periódicos Capes, and Scielo. The research addressed the benefits and challenges of modernizing the Brazilian electricity system, with an emphasis on the integration of renewable sources, such as solar and wind, and on combating non-technical losses. The results indicate that smart grids contribute to greater efficiency in the energy distribution system, enabling real-time management, in addition to promoting better security against failures and cyber threats. Another relevant point identified was the importance of training professionals capable of implementing these new technologies. The research concludes that the adoption of Industry 4.0 in the energy sector is a necessary step towards the sustainability and modernization of the electrical system in Brazil.

Evaluasi Metode Health Index Untuk Menentukan Prioritas Pemeliharaan Gardu Distribusi

Electricity is an essential energy source that plays a crucial role in human life. A key component of power distribution systems is the distribution substation. As distribution substations are in operation over time, their components experience aging, which can result in operational failures. This situation emphasizes the necessity for regular evaluations and diagnostics of distribution substations. Such assessments are crucial for identifying when equipment requires repair or replacement, ensuring that the system operates at maximum efficiency. By implementing a proactive maintenance strategy, utilities can mitigate risks, enhance reliability, and extend the lifespan of their infrastructure. The scoring matrix method is a technique for evaluating the condition of distribution substations. It combines results from field and laboratory tests to produce values that accurately reflect the substation's condition. The research focused on four distribution substations managed by PT PLN, classifying them into high, medium, and low categories based on their health index scores. The results show that, among the four distribution substations evaluated, substations A and C received health indices exceeding 80%, classifying them in the high category. It is therefore recommended that these substations continue operating normally while adhering to their scheduled periodic maintenance. In contrast, substation B received a health index between 50% and 80%, placing it in the medium category. While it can remain operational, it requires closer monitoring and maintenance at specific intervals to ensure reliability and prevent potential issues.

Receiving-End Voltage Compensation Method with NPC-Inverter-Based Active Power Line Conditioner in Three-Phase Four-Wire Distribution Feeder

This study proposes a receiving-end voltage compensation method employing a phase-specific reactive power control strategy with a neutral-point-clamped (NPC) inverter in a three-phase four-wire distribution system. The principle of the proposed receiving end voltage compensation method is explained. Further, the proposed control strategy can solve the problems of the three-phase, four-wire distribution system, which are an increase in the neutral-line current and the unbalanced voltage. Computer simulation is performed to confirm the validity of the proposed method. The simulation results indicate the receiving-end voltages can be compensated using the proposed method.

Spark: A Statistical Comparison and Evaluation of Classification Algorithms for Fault Prediction in Electrical Secondary Distribution Network

Managing faults in the electrical secondary distribution network is a challenging task given the nature, size, and complexity. Predicting faults early before they occur helps in increasing the safety and reliability of the power distribution system. Various statistical and machine learning techniques are being used to predict different types of faults. This study applies classification algorithms available in the big data framework Apache Spark through its python interface PySpark to predict electrical secondary distribution network faults. The study evaluates and compares nine algorithms: Decision tree, Gradient-boosted tree, Logistic regression, Naïve Bayes, Multilayer perceptron, Random forest, Linear Support Vector Machine, One-versus-rest and Factorization machines. The research uses Friedman’s test followed by the Nemenyi post hoc test to find the significance of performance differences among the algorithms. The results show significant differences among the algorithms. Gradient-boosted tree and One-versus-rest with Gradient-boosted tree had the best performance for binary and multiclass classification, respectively, while Naïve Bayes had the worst performance.

Water Volume and 3D Topographic Analysis of Hub Dam, Karachi, Using Remote Sensing and Global Bathymetry Data

Background: Karachi one of the largest and fastest-growing cities in the world, the city faces severe water scarcity and aggravated by climate change, excessive groundwater extraction in dense urban areas and inefficient water distribution systems. The Hub Dam, along with the Keenjhar Lake, is the source of water for Karachi's population as well as for the industrial and urban agricultural sectors. It is therefore important to have current information on the dam's storage capacity, its topographic features and the hydrological dynamics of its catchment area, which remains poorly understood to date. Objectives: This study's primary objectives are (1) to assess the hydrography of Hub Dam using global bathymetric and remote sensing data and (2) to create a detailed 3D model of the dam to facilitate analysis of its hydrological features. (3) Also generate data-driven insights to guide improvements in Karachi’s urban water management policies. Methods: The methodology integrates global bathymetric data with remote sensing and Google Earth Engine (GEE) for analysing Hub Dam’s hydrological and topographic characteristics. Data processing and visualization were conducted in Google Colab by python codes. This process enabling an efficient workflow for handling and analysing large datasets. Results: Hub Dam 3D model is developed. The approaches is enhancing visualization of the dam's water volume and terrain features to support detailed hydrological analysis. 3D volumetric analysis estimates with total water volume at approximately 79.954 · 106 m3. It was found that currently, the Hub Dam reservoir has enough water to fulfil Karachi needs for 503 days, a critical reserve for urban planning, resource management. Using a topographic analysis that includes surrounding slopes and watershed features, key elements affecting dam performance were identified. This result helps to adjust the filling of the dam with water. The Hub Dam's ability to store water was confirmed through a preliminary volume assessment. Conclusion: The study successfully achieved its objectives. The results obtained highlight the importance of adaptive well informed strategies for sustaining well managed water resources in response to environmental pressures. The current study further advance rational water management by integrating remote sensing and data-driven methodologies into this area of knowledge. That is, the effectiveness of Using Remote Sensing and Global Bathymetry Data has been repeatedly proven by other studies in different areas of knowledge. However, in the current study, this scientific approach has successfully demonstrated the efficient and rapid acquisition of accurate, up-to-date information on reservoir capacity and hydrological characteristics, which opens up new opportunities for efficient water management.

Streamlining logistics: Innovating cross-docking distribution systems for operational excellence

A logistics service company in Batam faces challenges related to warehouse load fulfillment and sorting inaccuracies. This study aims to identify proposed efficiency improvements to the goods distribution system using the cross-docking method. The research method chosen is cross-docking, a technique that eliminates the storage process in the warehouse, thus saving time and cost. The research findings show significant benefits, especially in achieving zero inventory efficiency. Data processing and discussion revealed that efficiencies were apparent by increasing the sorting tables from 1 to 6, with an output of 90,000 kg during aircraft loading and unloading (compared to approximately 77,000 kilograms). This efficiency arises from the larger output of the sorting tables compared to the input, eliminating the need for warehousing and adding ten trucks. As a result, the shipment can be completed in one trip, with no goods stored in the warehouse. The analysis shows that implementing cross-docking in the company increases efficiency in distributing goods to forwarding partners.

Sistem Pendistribusian Zakat oleh Baznas Kabupaten Langkat Menurut Undang – Undang No. 23 Tahun 2011 tentang Pengelolaan Zakat: Studi Kasus di Desa Karang Rejo, Kec. Stabat, Kab. Langkat

UU no. 23 of 2011 concerning Zakat Management as a complement to the previous law, namely Law no. 38 of 1999. This law provides institutional strengthening in integrated zakat management into a unified integrated system. In turn, the National Amil Zakat Agency becomes the only institution holding zakat authority, and the Amil Zakat Institution as a partner in assisting the National Amil Zakat Agency, as well as government oversight as a regulator. The research aims to answer the problem of how the distribution of zakat according to zakat law no. 23 of 2011 in Kab. Langkat. How is the zakat distribution system by BAZNAS Langkat Regency in Karang Rejo Village. What are the factors that cause delays in the BAZNAS distribution system in Langkat Regency. How is the strategy carried out by BAZNAS Langkat Regency to increase the collection and effectiveness in distributing zakat in Karang Rejo Village, Langkat Regency. This research is a qualitative research using a legal sociology approach. The types of data used in this study are primary data and secondary data, secondary data as initial data obtained from primary and secondary legal materials, then followed by primary data or field data obtained from documents and interviews with several Amil Agency officials Langkat District National Zakat. The results of the study show that the National Amil Zakat Agency in Langkat Regency has not run optimally in the distribution of zakat due to several obstacles, one of which is the lack of synergy with the local government in terms of regulations that have an impact on non-optimal distribution. Keywords: Distribution of Zakat, BAZNAS Kab. Langkat.

The role of automated surface water distribution systems in energy-saving agriculture: A case study from central Iran’s Arid Plateau

Study regionThe NekooAbad Irrigation District in central Iran faces challenges due to inefficient surface water distribution. 82 million m3 of groundwater is extracted annually from 15,000 tube-wells, leading to decreased groundwater levels and increased energy consumption of 234 million kWh per year. Study focusThis study explores implementing automation in surface water distribution to reduce groundwater extraction and conserve energy. A hydraulic simulation model and a centralized Model Predictive Control approach were used to analyze the existing system and propose a recovery plan. The potential impact of automated surface water distribution on reducing groundwater extraction and energy conservation was evaluated through spatial assessment in GIS. New hydrological insights for the regionThe results demonstrate that the introduction of automation can significantly improve surface water distribution and, accordingly, groundwater overexploitation and, consequently, energy conservation, particularly during water scarcity. Energy conservation increased by 42.3 %, 54.8 %, 56.2 %, and 57.7 % under normal conditions, with water shortages of less than 10 %, 10–15 %, and 15–20 %, respectively. However, as the surface water shortages intensified, the energy conservation rates decreased to 57.7 %, 43.7 %, 25.4 %, and 18.9 % for normal conditions, water shortages of 15–20 %, 20–30 %, 30–40 %, and over 40 %, respectively. The automation introduction effectively provided reliable surface water resources, prompting farmers to shut down pumping stations or reduce working hours. Even in extreme scenarios, the project achieved up to 18.9 % energy savings.

Improving the distribution system capability by incorporating ZnO nanoparticles into high-density polyethylene cable materials

This paper introduces a novel insulated cable designed to enhance the distribution system’s capabilities. Accordingly, high-density polyethylene loaded with varying concentrations of zinc oxide (ZnO) nanoparticles (NPs) ranging from 0.0 to 5 wt% was prepared using the melt-blending technique. Zinc oxide (NPs) is synthesized by using sol–gel technique and their microstructure was examined by X-ray diffraction. The new insulated cable, HDPE nanocomposite loaded with 1 wt% of ZnO, demonstrates a 43% reduction in the relative dielectric constant and a 16.5% improvement in breakdown strength compared to pure HDPE. The observed changes in both the dielectric constant and breakdown strength offer several advantages in electrical applications. These benefits include a decrease in feeder current at the same loading level, mitigation of inrush transients during load switching, and a reduction in earth fault current values, particularly in unearthed distribution networks with ungrounded cables. A comparative study is conducted between the conventional insulating cable based on the original material (HDPE) and the new insulated cable incorporating ZnO nanomaterial at a ratio of 1.0 wt% of the total cable mass per unit length. This comparison utilizes data from two actual medium-voltage distribution feeders. Both actual feeders are simulated using the EMTP/ATP package. The obtained results prove the efficacy of the developed material cable (polymer doped with ZnO NPs) compared to the base material. The peak and duration of inrush current can be cut to 77.3% and 67% of their original values, respectively. The earth fault current can be reduced to 56.5% in ungrounded networks, while substation current under the normal operation can be cut to 84.3% with the same load currents.

Fuzzy Multi-Agent Simulation for Collective Energy Management of Autonomous Industrial Vehicle Fleets

This paper presents a multi-agent simulation implemented in Python, using fuzzy logic to explore collective battery recharge management for autonomous industrial vehicles (AIVs) in an airport environment. This approach offers adaptability and resilience through a distributed system, taking into account variations in AIV battery capacity. Simulation scenarios were based on a proposed charging/discharging model for an AIV battery. The results highlight the effectiveness of adaptive fuzzy multi-agent models in optimizing charging strategies, improving operational efficiency, and reducing energy consumption. Dynamic factors such as workload variations and AIV-infrastructure communication are taken into account in the form of heuristics, underlining the importance of flexible and collaborative approaches in autonomous systems. In particular, an infrastructure capable of optimizing charging according to energy tariffs can significantly reduce consumption during peak hours, highlighting the importance of such strategies in dynamic environments. An optimal control model is established to improve the energy consumption of each AIV during its mission. The energy consumption depends on the speed, as demonstrated via numerical simulations using realistic data. The speed profile of each AIV is adjusted according to the various constraints within an airport. Overall, the study highlights the potential of incorporating adaptive fuzzy multi-agent models for AIV energy management to boost efficiency and sustainability in industrial operations.