Uninterruptible Power Supply Research Articles (Page 1)

This research presents a systematic method for developing an Energy Planning Blueprint for Stewart County, Georgia. The study focuses on energy efficiency, renewable energy integration, and economic improvement. A thorough analysis of current energy consumption, identification of efficiency gaps, and feasibility assessment of renewable energy sources have led to a strategic framework for energy transition. The outcomes include lower energy costs for county facilities and residents, as well as increased interest from renewable energy businesses. As part of the implementation, the project was applied to an emergency shelter to achieve energy self-sufficiency. This involved integrating renewable energy systems, enhancing energy efficiency measures, and ensuring uninterrupted power supply for critical operations. The findings demonstrate that such interventions can significantly reduce reliance on external energy sources, lower operational costs, and improve resilience in emergency response infrastructure. Stewart County has historically faced economic and demographic challenges, including population decline, low workforce participation, and a lack of high-paying jobs. The research demonstrates that energy efficiency improvements and renewable energy adoption can contribute to reversing these trends. The study evaluates existing energy sources, environmental impacts, and feasibility of renewable energy investments. The findings support policy recommendations that enable residents and businesses to adopt energy-efficient measures and transition to renewable energy solutions. The project was conducted in collaboration with Kennesaw State University experts. Major tasks included energy audits of county buildings, development of energy conservation guidelines, and feasibility studies of renewable energy projects. The project also resulted in the creation of an interactive online resource offering energy efficiency recommendations and renewable energy options for stakeholders. Collaboration with state agencies, renewable energy investors, and research institutions has helped position Stewart County as a leader in sustainable energy initiatives. The study's measurable impacts include reduced energy expenditures, improved air quality, job creation, and overall economic growth. The framework developed in this research can serve as a reference model for other rural communities aiming for a transition to clean and sustainable energy systems.

Enhancing state-of-health estimation for uninterruptible power supply systems using lithium batteries under constant-voltage charging scenario

The object of the study is the technical characteristics of autonomous trolleybuses and the systems that ensure their uninterrupted power supply. A key challenge is the dependence of conventional trolleybuses on contact networks, which limits their route versatility, complicates operations in historic city centers, bridge crossings, and regions with underdeveloped infrastructure. The article examines key technological aspects of autonomous trolleybuses, including types of charging stations (contact, inductive, with pantographs), charging efficiency, energy consumption, and autonomous range. Examples of the implementation of this technology in Ukraine are presented, along with an analysis of charging costs and energy characteristics for runs of 20–50 km. The prospects of using autonomous trolleybuses for optimizing the city transport network, reducing CO₂ emissions, and improving the quality of passenger service are emphasized. Calculations have been made of the energy required for a trolleybus to travel a distance of 20–50 km, taking into account the average energy consumption (1.2–2.0 kWh/km), charging station capacity (up to 100 kW,) and charging efficiency (0.9). Calculations have shown that for an autonomous trolleybus run of 30 km, 45 kWh of energy is required. Modern lithium-ion batteries and charging stations with a capacity of up to 100 kW provide a full charge in 30 minutes. Intermediate charging at stops minimizes contact infrastructure while maintaining transport system flexibility. Autonomous trolleybuses reduce dependence on contact networks, which is especially relevant for bridge crossings with complicated construction or maintenance and historic centers requiring architecture preservation without excess infrastructure. They also significantly reduce CO₂ emissions to promote ecological sustainability and improve urban air quality by lowering pollution and benefiting public health.

This study employs Gray Relational Analysis (GRA) to evaluate and compare various power supply devices, including switched-mode power supplies, linear power supplies, uninterruptible power supplies, battery packs, and solar power systems. The analysis focuses on four critical parameters: power requirements, efficiency, environmental factors, and noise sensitivity. The research methodology involves normalizing data, calculating deviation sequences, and determining Gray Relation Coefficients for each device across the four parameters. The final step computes the Gray Relation Grade (GRG) to rank the power supply options. Results indicate that battery packs emerge as the top-ranked power supply device with a GRG of 0.8333, excelling in power requirements, efficiency, and environmental factors. Solar power systems secure the second position with a GRG of 0.5525, demonstrating a balanced performance across all criteria. Linear power supplies, switched-mode power supplies, and uninterruptible power supplies follow in descending order. The study highlights the importance of considering multiple factors in selecting power supply devices for various applications. While battery packs show overall superiority, each type of power supply exhibits unique strengths suitable for specific use cases. The analysis underscores the need for a holistic approach in power supply selection, taking into account not only efficiency but also environmental impact, noise sensitivity, and power requirements. The strong performance of battery packs and solar power systems indicates a trend towards more sustainable and flexible power solutions. Future developments may focus on improving the efficiency and environmental impact of these leading options while addressing the specific strengths of other power supply types to create more versatile and optimized power solutions.

Cardiovascular disease (CVD) encompasses various heart conditions, such as arrhythmias, congenital heart diseases, and strokes. This review focuses on the remote monitoring of CVD patients by discussing the already available devices, the architecture of the CVD remote monitoring system, the challenges, and future perspectives. CVDs have become a major cause of morbidity and mortality globally, responsible for about 30% of all diseases. Risk factors for CVD include demographic characteristics, smoking, genetic factors, and lifestyle habits, such as obesity and physical inactivity. CVDs are no longer limited to developed countries, with 80% of CVDrelated mortality occurring in developing nations. Remote Patient Monitoring (RPM) technology allows healthcare providers to monitor patients using wearable and non-wearable devices, enabling efficient evaluation and consultation for better patient care. In the case of CVDs, timely intervention hinges on regular symptom monitoring and response to treatment, with Remote Patient Monitoring (RPM) emerging as a key approach. This method allows automatic recording of patient data through various devices, including invasive ones, such as pacemakers and implantable cardioverter defibrillators. Non-invasive devices aid in long-term self-management by monitoring and transmitting data to prevent emergencies and enhance prognosis. Patients with serious CVDs may have cardiac implantable electronic devices that provide continuous physiological information, which can be analyzed using machine learning algorithms to identify risks. RPM devices can reduce hospitalizations and costs by enabling preventive interventions and medication management, ultimately enhancing healthcare systems' ability to provide remote care for CVD patients. Despite the numerous applications of the digital health system, challenges hinder its implementation in developing countries. The main challenge lies in the absence of ICT infrastructure in rural areas, which hinders the effectiveness of healthcare systems, along with the difficulty in obtaining electronic devices and ensuring an uninterrupted power supply, both of which hamper the deployment of ICT services and the adoption of digital health systems by healthcare professionals and consumers. Overall, addressing these challenges requires human resource training, universal standards for RPM advancement, and a change in stakeholders' perceptions towards digital health technologies in underdeveloped nations.

Abstract The increasing interconnection of offshore oil and gas platforms via submarine cables has heightened the need for enhanced power system stability. Transient stability is critical in these networks, as disturbances from operational faults or equipment failures may cause oscillations or system collapse. This study investigates the transient stability of a representative offshore oilfield power network using the Electrical Transient Analyzer Program (ETAP). Two critical fault scenarios are examined: generator disconnection and a three-phase submarine cable short circuit. Simulation results reveal that reducing the system load by 6 MW within 0.15 s after a generator cut-off, and by 5.3 MW following a submarine cable fault, effectively restores power angle, voltage, and frequency stability. These findings provide practical guidelines for energy management strategies to enhance resilience and ensure uninterrupted power supply in offshore environments.

Coordinated optimization of distributed energy system and storage-enhanced uninterruptible power supply in data center: A three-level optimization framework with model predictive control

The energy sector of any country is a strategic one, even in peacetime. Its importance in creating general technological conditions for production and prices for national products, its impact on the quality, cost and comfort of life of the population, its role in shaping macroeconomic characteristics of employment, production scale, foreign trade and inflation in the country, and its significant anthropogenic impact on all components of the environment characterize the key importance of energy in the development of economic, environmental, social and security components of the national economic system. Russia's military aggression has created new internal challenges for the energy sector of our country (physical destruction of energy facilities, reduction of capacity, the need to diversify generation sources, reliability and uninterrupted power supply, etc.), which has strengthened its importance for the current survival and future sustainable development of Ukraine. The purpose of the article is to study the main indicators of the energy sector of modern Ukraine in general and the electric power industry as its key component, to identify transformations caused by military actions. The conducted research allows us to conclude that the full-scale invasion significantly affected all economic characteristics of the electric power industry of our country, changing its absolute and structural characteristics. The electric power sector is going through a difficult stage of transformations, when, in accordance with internal challenges, it is necessary to actively rebuild energy generation and transportation, taking into account the requirements for its diversification, decentralization and national security, and in accordance with external global challenges, it is necessary to take into account the requirements for environmental friendliness and energy efficiency, rational use of nature and prevention of climate change. It can be stated that the energy sector of Ukraine in general and its key component, the electric power industry, despite the destructive negative consequences of military aggression, still performs the basic functions assigned to it of providing all consumers with energy of the appropriate quantity and quality. The country's energy system remains unified and stable thanks to the dedicated work of energy professionals and significant state and international support.

Relevance of the study lies in the development of intelligent power supply systems (IPS), which implies the improvement of existing, implementation and improvement of modern protection, diagnostic systems, monitoring of high-voltage electrical equipment (HVE) elements.The purpose. To consider modern state, as well as the ways of development and possibilities of integration of protection and diagnostic systems of cable-overhead lines (COL) of IPS.Methods. For solving the problem, a comparative analysis of the reasons that lead to the operation the protection systems of the COL of IPS, their shortcomings and possible ways of their improvement were carried out. The current state of protection, diagnostics, monitoring of COL of IPS and the ways of their development were analyzed. In particular, promising methods for diagnosing insulation, coupling joints of cable lines (CL) according to the characteristics of partial discharges (PD), overhead lines (OL) elements according to the data of thermal imaging inspection were considered. RESULTS. The article provides an overview of existing protection and diagnostic systems for COL of IPS of high and medium voltage classes. The article is devoted to current issues protection development of ISE of distributed generation, which include renewable energy source (RES) generators, in order to prevent overvoltage and ensure uninterrupted power supply to consumers in distributed generation systems. The article considers current issues of development of modern methods of COL diagnostics up to the level of monitoring systems, including using thermal imaging survey methods, dielectric impedance spectroscopy (DIS), and the PD method.Conclusion. Development of ISE will be one of the main task for a long time. The most advanced ISE protections will be adaptive protections using artificial neural networks (ANN) in which be integrate the most modern mathematical algorithms and diagnostic methods, primarily smart grids technologies, microgrids technology, independent component method (ICM), PD methods, thermal imaging survey, electrical impedance spectroscopy (DIS), and dielectric spectroscopy (DS).

The global uninterruptible power supply forecast market is estimated at nearly USD 4.04 billion in 2024 owing to the growth in demand at data centers and other crucial sectors. Despite the great deal of information available in battery research, most of the literature on uninterruptible power supply does not consider the variability (temperature, depth of discharge, duty cycle) and mode of operation (grid-interactive vs. Standalone) performance during other operational modes. This review overcomes these deficiencies by providing three contributions: (1) variability in uninterruptible power supply specific quantitative performance metrics; (2) a growth map predicting the adoption of various battery chemistries in UPS on a short, medium, and long-term basis; (3) a sustainability assessment through the lens of primary materials, recyclability, and costs from the life cycle. Representative outcomes include: low-cost standby solutions from VRLA batteries, but limited cycle life (500–1,500 cycles); continuous UPS applications are dominated by LFP and LTO chemistries, which have a high tolerance to deep cycles; Li–S batteries have a high energy density (350–600 Wh/kg), but poor cycle life (<1,000); flow batteries have limited energy power density, but excel in longevity (>10,000 cycles) and are still too bulky for compact uninterruptible power supply systems. These conclusions provide a reasonable assessment of the cross technology trade-offs and the underlying research gaps to derive a pathway towards next generation reliable UPS batteries.

ABSTRACT Recent inverter topologies based on switched capacitors are ideal for Uninterruptible Power Supply (UPS) applications, enabling one-stage DC to AC power conversion along with improving system performance. The new multi-level inverter circuit, based on a high-gain, soft-charged switched-capacitor (SC), features two switched capacitors, eight power switches, two diodes, and a triple voltage gain for a seven-level output voltage. The proposed design addresses the issue of inrush currents through capacitors with the usage of a charging inductor to steady-state charge the capacitor. Other key design features include a smaller number of power switches having low voltage stress and self-voltage balancing of capacitor voltages. The merits of the suggested topology are demonstrated through extensive comparisons with similar topologies and a hardware prototype for testing.

Energy management is a key issue for energy security and policy in meeting the electricity demand in small tourist settlements, especially those located in locations that do not guarantee stable and sufficient energy supply from the power grid and renewable energy sources with energy storage. The integration of intermittent renewable energy sources increases the difficulty of managing the electricity grid and maintaining the balance of electricity supply and demand, especially in small tourist settlements. A holistic approach to electricity management takes into account all the above aspects and presents the concept of using municipal waste for energy production in a biogas plant supported by photovoltaic systems and shared electricity storage to ensure uninterrupted power supply for a small tourist settlement. The study also shows how energy storage management can be used to adjust the size and manage the supply and demand of energy in the settlement based on the optimization of energy consumption for own needs. It is also shown that we can achieve the goals of the circular economy and sustainable development of local communities by using the waste utilization. The novelty of the study is the basis for assessing the energy storage capacity and the size of renewable energy sources in order to balance the energy management process without the need for grid power supply and using only biodegradable municipal waste for biogas supply and solar energy for electricity production, thus ensuring its uninterrupted supply for a small tourist settlement.

Neural network sliding mode control of three-phase multilevel inverters for uninterruptible power supply applications

The non-fossil fuel generator is a flywheel energy storage system (FESS), which has attracted new research attention recently in applications like power quality, regenerative braking, and uninterruptible power supply (UPS). As a sustainable energy storage method, flywheel energy storage has become a direct substitute for batteries in UPS and other electrical applications. This project work, however, presents an overview of the applications of FESS in power systems and micro grids (MG) and also analyzes the design parameters to improve the energy density of the fuel-less generator. The aim is to improve its value and enhance its applications in numerous fields, such as renewable power generation. At the end of the project work, it was observed that the speed of the flywheel and generator pulley has a linear relationship. Varying the size of either the motor wheel or the flywheel that is connected to the generator will affect the amount of voltage produced and also the amount of work done on the system. Thus, increasing either of them will increase the speed of the generator and, thus, increase the voltage produced. This shows that the higher the speed, the more the voltage supplied, and vice versa. On testing the generator, the output voltage generated was 101V at a speed of 234rpm on the flywheel.

The growth of modern industry directly connects to the introduction of a wide variety of electrical apparatus and complex electronic devices. This growth inevitably leads to a significant increase in electricity consumption. As a result, industrial facilities require an uninterrupted power supply. Voltage sags present a serious obstacle in this process, causing disruptions in operations and equipment failures, which can lead to costly downtimes and increased maintenance expenses.Objective. This study aims to analyze the issue of ensuring voltage stability at industrial enterprises in the context of voltage sags.Methods. The research includes an overview of existing engineering measures designed to neutralize voltage sags. These measures encompass both hardware solutions, such as UPS systems and voltage regulators, and software strategies that monitor and manage electrical loads.Results. The article discusses the relevance of the topic, defines voltage sags, and outlines the main characteristics of this phenomenon, including depth and duration. The analysis presents data on the primary causes and effects of voltage sags at various enterprises. It evaluates available means and methods for minimizing the impact of voltage sags on technological processes, thereby enhancing operational efficiency.Conclusion. Each method for addressing voltage sags comes with its own advantages and disadvantages. Moreover, some methods influence the depth of the failure while others affect its duration. Users should justify the choice of method based on the specific requirements of each electrical system, ensuring compatibility with other technological processes during the design phase. By thoughtfully applying these strategies, businesses can enhance their operational resilience against voltage disturbances.

This article presents the design and implementation of an Automatic Transfer Switch (ATS) system with automatic generator activation, aimed at ensuring the continuity of electricity supply from the National Electricity Company (PLN) grid, photovoltaic (PV) systems, and generator sets (Gensets). As reliance on the PLN grid is often compromised by various disruptions, including short circuits and natural disasters, integrating reliable backup energy sources is essential for maintaining operational efficiency across critical sectors such as healthcare, education, and industry. The ATS is structured to facilitate seamless transitions between power sources, minimizing downtime and enhancing system reliability. Test results demonstrate the ATS's effectiveness in managing switching processes, showing minimal voltage fluctuations and flicker durations, which underscores its capability to sustain uninterrupted power supply. By employing advanced monitoring technologies, this ATS system not only optimizes energy management but also bolsters the resilience of electrical infrastructure, addressing the growing need for dependable electricity in an increasingly variable energy landscape.

The use of technologies aimed at increasing energy efficiency and energy independence of technological processes is a key direction in the development of the oil and gas industry. For gas infrastructure facilities, it is possible to use the energy released when reducing the gas flow. For this purpose, installations based on turboexpanders are used. Their use for generating electricity allows to provide power supply to consumers of the gas infrastructure facility and reduce or abandon gas consumption for technological processes. In order to increase the energy independence of gas infrastructure facilities, it is advisable to use backup power sources. For these purposes, the use of cogeneration plants based on gas piston engines is proposed. Their use does not require diesel fuel, which reduces operating costs. Thermal energy released during the operation of the cogeneration plant can be used in technological processes of the gas infrastructure facility. To ensure uninterrupted power supply, it is necessary to use energy storage systems. Storage systems based on chemical elements and inertial accumulators are considered. The options for constructing an uninterrupted power supply system for gas infrastructure facilities have been proposed and analyzed. It has been shown that the smallest overall dimensions will be those of a plant that contains a piston engine, an inertial storage device and an electric generator integrated into a single module. Further development of the proposed concept consists in creating energy generation systems using expander-generator units and cogeneration plants. This will ensure the power supply of critical consumers during long power outages, which will increase the stability of operation of both gas infrastructure facilities and external consumers of critical infrastructure.

In modern power distribution networks, ensuring uninterrupted power supply with minimal losses is critical, especially for sensitive and critical loads. Static Transfer Switches (STS) play a key role in maintaining continuity by rapidly switching between two independent power sources during disturbances. However, conventional STS control strategies often rely on predefined thresholds and do not consider the dynamic state of the network, leading to inefficient switching and increased power losses. This paper proposes a novel approach to enhance the performance of STS by integrating advanced state estimation techniques. Using real-time estimation of voltage magnitudes, phase angles, and system stability indicators is performed. These estimated parameters are then used to intelligently control the switching operation of the STS, selecting the optimal source based on system health and expected power loss. A simulation model is developed in MATLAB/Simulink to evaluate the proposed method under various fault and load conditions. The results acquired demonstrated the competency of the proposed approach to endow improved voltage stability, reduced switching time, and significant minimization of power distribution losses as compared to traditional switching approaches. This work highlights the potential of state-estimation-based control in making STS operations more adaptive, reliable, and energy-efficient in smart distribution networks.

The article is devoted to increasing the efficiency of design, analysis, evaluation, and ensuring the reliability of highly responsible systems, such as an autonomous power supply system (APS) for farms and other critical infrastructure. The reliability of APS is an essential factor for modern technological processes, automated control systems, and agricultural enterprises, where even short-term power interruptions can cause significant economic losses, data loss, and affect human safety. The study provides a comprehensive analysis of the structure, operating modes, and failure characteristics of APS with hierarchical configurations, focusing on both continuous operation and periodic preventive and repair activities in accordance with current regulations. The paper reviews recent research and publications in the field of autonomous power supply systems, including the use of renewable energy sources (RES) and hybrid configurations. The analysis highlights the main factors influencing the choice of optimal APS configuration, such as the reliability of centralized power supply, the required backup capacity, the duration of autonomous operation, the level of automation, and economic feasibility. Two main design variants are considered: systems based solely on uninterruptible power supplies (UPS) with battery storage, and combined systems integrating UPS with minimal battery capacity and autonomous diesel or gasoline generators. The advantages and limitations of each solution are discussed in detail, including capital and operational costs, battery life, and the impact of automation on reliability and investment. The article presents cost analysis graphs for different APS configurations, demonstrating the economic justification for using UPS with batteries for backup capacities up to 1.5 kVA and short autonomous operation periods (up to 2–3 hours). For higher capacities and longer operation times, combined systems with autonomous generators offer significant advantages in terms of reliability and cost-effectiveness. The study emphasizes the importance of structural reliability analysis, using block diagrams and mathematical modeling to assess system reliability indicators at all life cycle stages, from design to operation. Special attention is given to the peculiarities of APS operation, such as the use of both permanently active and standby reserve elements, logical redundancy, and the need for parallel power supply chains to ensure uninterrupted and guaranteed power for critical consumers. The article concludes that the reliability of APS is determined by numerous factors, including the reliability of generating units, the ratio of their capacities, the availability of renewable sources, and the specifics of battery operation. The findings confirm the practicality of using combined backup schemes to enhance the economic efficiency and reliability of APS, especially for capacities above 1.5 kVA and extended autonomous operation.

This study examines the implementation and optimization of solar photovoltaic (PV) systems in mission-critical infrastructure facilities across the United States, with particular emphasis on reliability-centered maintenance (RCM) methodologies. Critical infrastructure facilities, including hospitals and data centers, require uninterrupted power supply to maintain essential operations. While solar PV systems offer resilience benefits and reduced environmental impact, their integration into critical infrastructure demands rigorous performance optimization and reliability assurance. This paper presents a comprehensive framework for optimizing solar PV system performance in these environments, analyzing case studies from diverse geographical regions in the US, and proposing a systematic approach to maintenance optimization under various stress conditions. Findings indicate that RCM approaches can enhance system availability by up to 27% while reducing lifecycle costs by 18-23% compared to traditional maintenance strategies. The research contributes to the understanding of solar PV reliability in mission-critical contexts and provides actionable guidelines for facility managers and energy system designers.