Distribution System Reliability Research Articles

A Proposed Mathematical Model for Networked and Distributed System Reliability Evaluation in Tanzanian Universities

A Proposed Mathematical Model for Networked and Distributed System Reliability Evaluation in Tanzanian Universities

Performance Evaluation of Overcurrent Relay and Ground Fault Relay Coordination in Distribution Feeder

Reliable and sustainable electrical distribution systems require effective protection measures against internal and external disturbances, especially short-circuit disturbances, to avoid damage to the equipment. Overcurrent relays (OCR) and ground fault relays (GFR) play an important role in the safety of the distribution network. To improve performance, evaluation of relay coordination is essential. During the short circuit, the nearest relay to the fault point is activated first and the backup relay is activated if the fault current exceeds the adjustment of the main relay. Coordination ensures that timely signaling is sent to interrupt the circuit. Inspection of the OCR relay revealed that it did not comply with the IEC 60255 standard and consequently adjusted the classification time to 0.402 seconds. Similarly, the results of the GFR relay inspection did not meet the standards and required an adjustment of the evaluation time to 0.492 seconds. Resolving these deviations is crucial to maintaining the reliability and compliance of the distribution network with industry standards, ensuring that the protection relays respond quickly and effectively to disturbances, thereby preventing possible damage to equipment

Improving Reliability in Distribution Systems through Optimal Allocation of Distributed Generators, Network Reconfiguration and Capacitor Placement

Improving Reliability in Distribution Systems through Optimal Allocation of Distributed Generators, Network Reconfiguration and Capacitor Placement

Overview of Distribution System Reliability Optimization Against Lightning

The reliability of the distribution system relies on the occurrence of lightning phenomena, which can significantly affect the distribution of electricity and result in power service disruptions. Therefore, ensuring the reliability of the distribution system is an ongoing challenge that necessitates continuous research for optimal solutions. Researchers have always developed solutions that are always up to date by leveraging advancements in mathematics, engineering technology, and management strategies. This paper presents a comprehensive summary and discussion of various optimization models for enhancing system reliability. It offers an overview of commonly employed mathematical programming techniques and algorithms for Lightning Protection Systems (LPSs), while also highlighting the influence of lightning phenomena on these solutions. The focus of this paper is to present the engineering aspects behind the development of modern LPSs. It encompasses historical reliability data, technical limitations, and economic considerations. By utilizing operations research and optimization theory, researchers have been able to devise more effective approaches for addressing reliability issues, even in highly intricate systems across different domains. Technological advancements have prompted researchers to adopt a new perspective on solving reliability problems, based on practical engineering requirements. In conclusion, the continuous progress in mathematics, engineering technology, and management approaches has enabled researchers to tackle the challenges associated with distribution system reliability. This paper serves as a valuable resource, providing insights into the development of modern LPSs and offering guidance on optimizing system reliability in various practical engineering scenarios.

Electrical power projects: the role of risk management and reliability

The management of power outages caused by severe weather disasters such as earthquakes, tornadoes, and weather disturbances is critical in power transmission and distribution systems. The transmission system is the key to any power system and can trigger severe or significant effects if it fails. Different causes of fires, extreme weather conditions, ageing components, poor maintenance and malfunctions, human error, mal-operative procedures, and high operating network variables may cause transmission components to fail. System reliability is the probability that, despite component failures, a system remains available or functional. Risk management of the failures describes it. There are several methods to predict the failure rate, including exponential and Bayesian distributions. In this study, Poisson distribution forecasted the outage patterns for transmission and distribution networks for one and five years. A probability distribution function generated this pattern. Moreover, previous data were obtained from the National Electric Power Regulatory Authority (NEPRA). On comparing the acquired results with previous outage data, it was reported that the average outages in the transmission system were 567. The average outages in the distribution system stood at 37 for five years with a 100% confidence level. However, the probability of getting 620 transmission outages and 50 distribution outages was the highest in the probability distribution function for five years. Poisson distribution proved to be a useful tool to assess the transmission and distribution system reliability by estimating the failure rate over the years. It would allow the risk professionals to schedule, reduce, and track the systems’ risks. It would also help to improve the system’s reliability.

Optimisation of the Distribution System Reliability with Shielding and Grounding Design Under Various Soil Resistivities

Lightning strikes can cause equipment damage and power outages, so the distribution system's reliability in withstanding lightning strikes is crucial. This research paper presents a model that aims to optimise the configuration of a lightning protection system (LPS) in the power distribution system and minimise the System Average Interruption Frequency Index (SAIFI), a measure of reliability, and the associated cost investment. The proposed lightning electromagnetic transient model considers LPS factors such as feeder shielding, grounding design, and soil types, which affect critical current, flashover rates, SAIFI, and cost. A metaheuristic algorithm, PSOGSA, is used to obtain the optimal solution. The paper's main contribution is exploring grounding schemes and soil resistivity's impact on SAIFI. Using 4 grounding rods arranged in a straight line under the soil with 10 Ωm resistivity reduces grounding resistance and decreases SAIFI from 3.783 int./yr (no LPS) to 0.146 int./yr. Unshielded LPS has no significant effect on critical current for soil resistivity. Four test cases with different cost investments are considered, and numerical simulations are conducted. Shielded LPSs are more sensitive to grounding topologies and soil resistivities, wherein higher investment, with 10 Ωm soil resistivity, SAIFI decreases the most by 73.34%. In contrast, SAIFIs for 1 kΩm and 10 kΩm soil resistivities show minor decreases compared to SAIFIs with no LPS. The study emphasises the importance of considering soil resistivity and investment cost when selecting the optimal LPS configuration for distribution systems, as well as the significance of LPS selection in reducing interruptions to customers.

Study on the Preparation and Aging Performance of Temperature-Indicating Patch Used for Thermal Defect Detection of Transformer Bushing Cylinder Head

Elevated temperatures at the transformer bushing cylinder head can precipitate failures, leading to significant power outages. In response, this study introduces a reversible temperature-indicating patch for the nuanced detection of thermal anomalies in the transformer bushing’s cylinder head. The patch, crafted through a melting process, utilizes a reversible discoloration material and is developed in two variants via an adsorption substrate method. Comprehensive evaluations of the patches’ color-changing characteristics, alongside their electrical and hydrophobic properties, were conducted using an automatic contact angle measuring instrument and an AC flashover test platform. The findings reveal that the temperature-indicating patch exhibits a discernible color transition within the range of 49~55 °C, with a color reversion temperature span of 45~55 °C, denoting marked sensitivity and robust reversibility. Additionally, it was observed that prolonged thermal aging correlates with a decrease in both the water contact angle and the discharge voltage per unit length across the surface of the patches, indicating a degradation in performance. Among the variants, the binder-based temperature-indicating patch demonstrated superior stability in electrical performance compared to its vacuum-based counterpart. The outcomes of this research offer valuable insights for the development of advanced diagnostic tools for the identification of thermal defects in transformer bushings, potentially enhancing reliability and safety in power distribution systems.

Loss of Life Transformer Prediction Based on Stacking Ensemble Improved by Genetic Algorithm By IJISRT

Prediction for loss of life transfomer is very important to ensure the reliability and efficiency of the power system. In this paper, an innovative model is proposed to improve the accuracy of lost of life transfomer prediction using stacking ensembles enhanced with genetic algorithm (GA). The aim is to develop a robust model to estimate the remaining life of a transformer in order to generally increase the reliability of the electrical energy distribution system. This approach involves integrating various machine learning models as a basic model, namely Support Vector Machines (SVM) and K-Nearest Neighbor (KNN). A stacking ensemble framework is then used to combine the predictions of these base models using a meta model namely Logistic Regression (LR). The results show a significant improvement in both transformers using stacking-GA, both TR-A and TR-B, with each prediction evaluation 99% and with a minimal error rate, namely approaching 0.the developed framework presents a promising solution for accurate and reliable transformer life prediction. By integrating a variety of basic models, applying improved stacking layouts using GA, these models offer valuable insights to improve maintenance strategies and system reliability in power grids.

Pioneering Maintenance Strategies for Enhanced Reliability of Low Voltage Switchboards

This study highlights the critical need for rigorous maintenance protocols, focusing on routine inspections, preventative measures, and timely corrective actions. Low voltage switch panels (PHB-TR) are vital for ensuring the efficiency and reliability of electricity distribution systems. Through systematic analysis of existing maintenance procedures and field evaluations across diverse setups, the research confirms that structured maintenance not only mitigates the risk of failures but also significantly reduces workplace accidents. The findings advocate for strict adherence to standard operating procedures and improved coordination among technicians, suggesting these strategies as global standards for enhancing the safety and functionality of electrical distribution networks. Highlights: Proper maintenance ensures optimal performance and reduces the risk of system failure. Adherence to applicable SOPs is crucial to prevent work accidents. Coordination and adherence to job distribution streamline work execution. Keywords: PHB-TR Maintenance, Split Switch Panel Maintenance, Low Voltage Split Switch Board

Testing of The Insulation Resistance and Turns Test Ratio (TTR) of The Distribution Transformers at PT PLN (Pesero) UP3 Sidoarjo

Electricity plays a vital role in human life and the economic growth of Indonesia. Therefore, a reliable electrical transmission and distribution system is essential. Transformers, especially in an industrial context, play a key role in power supply. Transformer maintenance is a critical step in maintaining a stable flow of electricity. This study adopts the Research and Development (R&D) method and focuses on measuring insulation resistance and voltage ratios in the context of transformer maintenance. The research was conducted at the Pole Transformer Substation (GTT) in P. Melati, Sidoarjo Regency, East Java, starting in August 2023. The research variables involve measuring the insulation resistance referring to IEC standards and measuring the voltage ratio to ensure proper transformer performance. The test results indicate that the insulation resistance in the transformer, both on the primary and secondary sides, meets the standards, demonstrating that the transformer functions well and safely. Voltage ratio measurements closely approximate theoretical calculations and fall within a tolerance of ± 0.5%. This study underscores the importance of transformer maintenance in maintaining a stable flow of electricity. Proper maintenance will prevent disruptions that can be detrimental, such as current leakage or short circuits. With good maintenance, the continuity of a reliable and safe electricity distribution service for consumers can be ensured.

Effects of integration of distributed generation on reliability in distribution system

The reliability of power supply to consumers is the main factor that is to be considered while designing, planning and operation of a distribution network. This problem can be solved by incorporating distributed generation (DG) at the consumer side itself. In order to enhance service availability, power quality, reliability, and loss reduction, DG is positioned optimally at the consumer end within the system. The optimal DG location and size is to be calculated in such a way that the total loss in the system should be minimal and cost savings should be maximal. In this study, for the investigation of effects of DG on reliability of distribution system, a practical 11 KV feeder with 41-bus, was employed. The selected practical feeder is modelled using the power world simulator (PWS) software and reliability of the system is verified by calculating various reliability indices such as system average interruption frequency index (SAIFI), system average interruption duration index (SAIDI), customer average interruption duration index (CAIDI), average system utility index (ASUI) and average service availability index (ASAI). After applying proposed loss sensitivity factor (LSF) method, the active and reactive power loss reduction are 41.30 % and 38.64 % respectively, least bus voltage is enhanced to 0.9405 pu from 0.8978 pu and the reliability indices are also improved.

A Review Article on Analysis and Design of Water Distribution Network for Jabalpur antonment Board Area

The provision of a reliable and efficient water distribution system is fundamental for ensuring adequate water supply to urban areas. This review article aims to analyze and evaluate the design aspects, hydraulic performance, and challenges related to the water distribution network in the Jabalpur Cantonment Board Area. The study comprehensively examines the current state of the water distribution system, evaluates its operational efficiency, and proposes recommendations for enhancing its performance and sustainability.The review commences by providing an overview of the Jabalpur Cantonment Board Area, highlighting the demographic, geographic, and infrastructural aspects relevant to the water distribution network. It delves into the existing system layout, network configuration, pumping stations, reservoirs, pipe materials, and other infrastructure components contributing to the distribution of potable water to the residents.Furthermore, the review article conducts a detailed analysis of hydraulic modeling techniques and software applications utilized in assessing the performance and optimization of the water distribution network. It scrutinizes factors influencing network efficiency, including water demand patterns, pressure management, leakage detection, and water loss reduction strategies.Through a critical evaluation of the existing challenges faced by the water distribution network in Jabalpur Cantonment, the review identifies issues such as aging infrastructure, inadequate maintenance, uneven distribution, non-revenue water, and insufficient pressure management.

Financial Analysis for a Multi-Carrier Energy System Equipped with CCHP

The interest on distributed generation has been increasing in recent years, especially due to technical development on generation systems that meet environmental and energy policy concerns. One of the most important distributed energy technologies is Combined Cooling, Heat and Power (CCHP) systems. CCHP is a small and self-contained electric, heating and cooling generation plant that can provide power for household applications, commercial or industrial facilities. It can reduce power loss and enhance service reliability in distribution systems. Since the input of a CCHP system is natural gas then natural gas price is so important in CCHP penetration level in DG’s market. In this paper authors by considering gas price, capital cost and also sales revenue, find the effects of these parameters in financial parameters for a multi-carrier energy system with optimal size and operation by applying COMFAR III software.

Ways to improve the reliability of gas supply systems

Background: The concept of reliability of gas distribution systems implies the possibility of reliable transportation of the required amount of gas to the consumer in compliance with the specified parameters in normal operation for a certain period of time.
 Aim: The peculiarity of gas distribution networks is that they are long-term planning systems, with the growth of cities and the connection of consumers, the radius of their impact increases, expands, rebuilds, worn-out nodes and elements are replaced with new ones. The main goal at this stage of operation is the absence of significant reconstruction measures to improve the reliability of the system.
 Materials and methods: Work has been carried out to analyze the probability of triggering, the failure rate and the probability of failures of gas supply systems for single indicators.
 Results: To ensure the reliability and durability of gas boilers during replacement, the following 8 different measures were proposed.
 Conclusion: The article proposes a closed circuit, the introduction of network redundancy in the system by ringing or duplicating elements and considers the social nature of gas distribution systems.

Power Loss Reduction and Reliability Improvement of Radial Distribution Systems Using Optimal Capacitor Placement Technique

Improving reliability and power quality in Radial Distribution Systems (RDS) is of large significance to ensure the provision of electricity within a reliable and acceptable standard to consumers with increasing load requirements. An Optimal Capacitor Placement (OCP) technique is used in the present work to achieve the highest power quality and system reliability in a balanced manner at the same time. The proposed technique has been tested with 69 typical IEEE RDS buses using the Improved Binary Particle Swarm Optimization (IBPSO) algorithm. The proposed algorithm shows a high ability to find the best location and size of injected capacitors inside the RDS to implement a single-objective function for minimization of Active Power Loss (APL). The simulation results obtained from the MATLAB environment show that the OCP technique has a significant potential to enhance RDS reliability, bus voltage, and loss reduction as compared to other previous work.

Techno-economic evaluation of meshed distribution network planning with load growth and expansion with multiple assets across multiple planning horizons

The smart grid paradigm has ushered in an era where modern distribution systems are expected to be both robust and interconnected in topology. This paper presents a techno-economic-based sustainable planning (TESP) strategy, which can be used as a planning framework for linked distribution systems, seeking to discover a realistic solution among competing criteria of diverse genres. In this comparative analysis-based study, three voltage stability assessment indices—VSA_A, VSA_B, and VSA_W—and a loss minimization condition (LMC)-based framework are used in the initial stage to achieve optimal distributed generation (DG)-based asset optimization for siting, followed by sizing. The respective techniques are evaluated across two variants of multiple load growth horizons spread across 10 years. The suggested TESP technique is tested on two variants of a mesh-configured microgrid (MCMG) with varied load growth scenarios. One variant considers a 65-bus MG with a fixed load growth of 2.7% across two load growth horizons. The other variant considers a 75-bus MG with varied load growth across four load growth horizons, encapsulating an expansion-based planning perspective. The numerical results of the suggested TESP approach in a comparative study demonstrate its effectiveness, and it can be used by researchers and planning engineers as a planning framework for interconnected distribution tools across multiple planning horizons. The proposed study would contribute to enhancing the robustness and interconnectivity of smart grid distribution systems. This dual focus could lead to more cost-effective and reliable power distribution systems.

Graphical Environment to Study Reliability of Electric Power Distribution Systems.

In this paper we present an application for reliability studies of electric power distribution systems. These studies are easily carried out using a graphical interface that allows interaction with the user. The program is capable of evaluating a reliability index and allows the modification of features related to the distribution network or related to the way in which service restoration is done when there is a fault in the system. Thus, it is possible to study several reliability improvement measures as shown in an example in this paper.

Improving Sustainable Energy Distribution in the USA: Leveraging the Theory of Constraints’ Thinking Process Tools

This study explores the improvement of sustainable energy distribution in the USA through the application of the Theory of Constraints’ Thinking Process Tools. The research adopts a mixed-methods approach, combining quantitative analysis of energy production, consumption, and transmission data with qualitative analysis of stakeholder perspectives and regulatory frameworks. The findings reveal key challenges, including infrastructure bottlenecks, regulatory barriers, and coordination issues among stakeholders. Through the application of the Theory of Constraints’ tools, targeted strategies are developed to address these constraints and enhance the efficiency, reliability, and sustainability of the energy distribution system. Recommendations are provided to invest in infrastructure upgrades, streamline regulatory processes, foster stakeholder collaboration, prioritize research and innovation, and promote public awareness and engagement. By implementing these recommendations, stakeholders can work together to overcome existing challenges and accelerate the transition towards a more sustainable energy future in the USA.

Optimizing Electricity Infrastructure Management: A Dashboard Approach for Samarkand Region

Electricity infrastructure management plays a pivotal role in ensuring the reliability and efficiency of power distribution systems. In this paper, we present a comprehensive approach to electricity infrastructure management in the Samarkand region through the development and implementation of a dashboard using ArcGIS Online. The dashboard serves as a centralized platform for stakeholders to visualize, analyse, and monitor various aspects of the electricity network. Key features of the dashboard include filters by district and sub-district, as well as options to select specific electricity lines by name and voltage level. This enables users to focus their analysis on specific areas of interest within the region, enhancing the granularity and relevance of the information presented. The implementation of this dashboard represents a significant step towards modernizing electricity infrastructure management practices in the Samarkand region. By leveraging the power of GIS technology and ArcGIS Online, stakeholders are empowered with a user-friendly and intuitive tool for accessing, analysing, and interpreting electricity infrastructure data.

Quantitative Analysis of Distribution and Reliability Based on Maximum Capacity Segmented Subscribers on Distribution Lines

The rapid economic progress and widespread use of sophisticated technology elevate the output value per kWh of electricity consumed, underscoring the paramount importance of maintaining an uninterrupted and dependable power supply to avoid substantial economic losses for consumers and society. Investigating the reliability of urban distribution systems emerges not only as a pivotal factor in enhancing power supply quality but also as a cornerstone of electric power modernization, significantly impacting production, technology, and management within the industry while bolstering its economic and social benefits. This study adopts a multifaceted approach: firstly, establishing a methodology for grid-side storage capacity distribution to mitigate substation load factors and implement peak shaving, thereby minimizing load discrepancies. Secondly, it develops a mathematical model encompassing diverse user distributions, employing analytical techniques to derive reliability indices and optimal segment numbers tailored to different user distributions. The research proposes segment optimization based on user distributions, considering both economic viability and reliability, showcasing an interdisciplinary amalgamation of combinatorial principles and scientific computing methodologies. This approach aims to optimize segment distribution, enhancing the reliability and economic feasibility of urban distribution networks through advanced mathematical and computational techniques.