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Öhnell, Richard F. "Some PQ problems." Acta Medica Scandinavica 130, S206 (2009): 17–19. http://dx.doi.org/10.1111/j.0954-6820.1948.tb12015.x.
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Goud, B. Srikanth, Ch Rami Reddy, Mohit Bajaj, Ehab E. Elattar, and Salah Kamel. "Power Quality Improvement Using Distributed Power Flow Controller with BWO-Based FOPID Controller." Sustainability 13, no. 20 (2021): 11194. http://dx.doi.org/10.3390/su132011194.
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The integration of hybrid renewable energy sources (HRESs) into the grid is currently being encouraged to meet the increasing demand for electric power and reduce fossil fuels which are causing environmental-related problems. Integration of HRESs into the grid can create some power quality (PQ) problems. To mitigate PQ problems and improve the performance of grid-connected HRESs some flexible devices should be used. This paper presents a distributed power flow controller (DPFC), as a type of flexible device to mitigate some PQ problems, including voltage sag, swell, disruptions, and eliminating the harmonics in a hybrid power system (HPS). The HPS presented in this work comprises a photo voltaic (PV) system, wind turbine (WT) and battery energy storage system (BESS). As a result, black widow optimization (BWO) with DPFC with real and reactive power (DPFC-PQ) is built in this paper to solve the PQ issues in HRES systems. The main aim of the work is to mitigate PQ problems and compensate for load demand in the HRES scheme. The controller used to drive this DPFC-PQ is a fractional-order PID (FOPID) controller optimized by the black widow optimization (BWO) technique. To assess the capability of BWO in fine-tuning the FOPID controller parameters, twelve optimization techniques were presented: P&O, PSO, Cuckoo, GA, GSA, BBO, Whale, ESA, RFA, ASO, and EVORFA. Additionally, a comparison between the FOPID controller and the classical PI controller is introduced. The results showed that the proposed BWO-FOPID controller for DFPC had mitigated the PQ problems in grid-connected HRESs. The system’s performance with the presented BWO-FOPID controller is compared with eleven optimization techniques used to optimize the FOPID controller and also compared with the conventional PI controller. The design of the proposed system is implemented in the MATLAB/Simulink platform and performances were analyzed.
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Sa'idu, Adamu, Nasiru B. Kadandani, and Bala Boyi Bukata. "A review of convolutional neural networks for classifying power quality problems using Keras API." Indonesian Journal of Electrical Engineering and Computer Science 38, no. 1 (2025): 1. https://doi.org/10.11591/ijeecs.v38.i1.pp1-21.
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<p>The major causes of electric power quality (PQ) problems are mainly due to the increased utilization of nonlinear loads, capacitor and load switching events, transformer energization, and occurrence of assorted faults at the distribution corridor. The problems often introduce harmonics and other waveform anomalies like voltage sags, voltage swells and interruptions along the power systems. A timely classification of such problems is important in understanding their impact on costly power system economy. The paper explores comprehensive review of PQ issues, operational concept of convolutional neural network (CNN) and its utilization in solving PQ problems. Novel deep learning (DL) approach using variant of DenseNet CNN technique in Keras API platform is deployed to extract the features of, and classify PQ problems. The proposed technique improves classification performance with an accuracy of 99.96%. It shows remarkable improvement over the traditional techniques in the literature which were 73.53% to 99.92% accurate for a period from 2018 to 2023. The most promising part of the method is the improvement shown in the classification performance when compared with that obtained in the literature. The technique can also be applied in real time to cater for real PQ problems.</p>
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Adamu, Sa'idu Nasiru B. Kadandani Bala Boyi Bukata. "A review of convolutional neural networks for classifying power quality problems using Keras API." Indonesian Journal of Electrical Engineering and Computer Science 38, no. 1 (2025): 1–21. https://doi.org/10.11591/ijeecs.v38.i1.pp1-21.
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The major causes of electric power quality (PQ) problems are mainly due to the increased utilization of nonlinear loads, capacitor and load switching events, transformer energization, and occurrence of assorted faults at the distribution corridor. The problems often introduce harmonics and other waveform anomalies like voltage sags, voltage swells and interruptions along the power systems. A timely classification of such problems is important in understanding their impact on costly power system economy. The paper explores comprehensive review of PQ issues, operational concept of convolutional neural network (CNN) and its utilization in solving PQ problems. Novel deep learning (DL) approach using variant of DenseNet CNN technique in Keras API platform is deployed to extract the features of, and classify PQ problems. The proposed technique improves classification performance with an accuracy of 99.96%. It shows remarkable improvement over the traditional techniques in the literature which were 73.53% to 99.92% accurate for a period from 2018 to 2023. The most promising part of the method is the improvement shown in the classification performance when compared with that obtained in the literature. The technique can also be applied in real time to cater for real PQ problems.
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Arov, D. Z., B. Fritzsche, and B. Kirstein. "Completion problems forj pq-inner functions. II." Integral Equations and Operator Theory 16, no. 4 (1993): 453–95. http://dx.doi.org/10.1007/bf01205289.
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Arov, D. Z., B. Fritzsche, and B. Kirstein. "Completion problems forj pq-inner functions. I." Integral Equations and Operator Theory 16, no. 2 (1993): 155–85. http://dx.doi.org/10.1007/bf01358952.
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Bhende, C. N., A. Kalam, and S. G. Malla. "Mitigation of Power Quality Problems in Grid-Interactive Distributed Generation System." International Journal of Emerging Electric Power Systems 17, no. 2 (2016): 165–72. http://dx.doi.org/10.1515/ijeeps-2015-0163.
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Abstract Having an inter-tie between low/medium voltage grid and distributed generation (DG), both exposes to power quality (PQ) problems created by each other. This paper addresses various PQ problems arise due to integration of DG with grid. The major PQ problems are due to unbalanced and non-linear load connected at DG, unbalanced voltage variations on transmission line and unbalanced grid voltages which severely affect the performance of the system. To mitigate the above mentioned PQ problems, a novel integrated control of distribution static shunt compensator (DSTATCOM) is presented in this paper. DSTATCOM control helps in reducing the unbalance factor of PCC voltage. It also eliminates harmonics from line currents and makes them balanced. Moreover, DSTATCOM supplies the reactive power required by the load locally and hence, grid need not to supply the reactive power. To show the efficacy of the proposed controller, several operating conditions are considered and verified through simulation using MATLAB/SIMULINK.
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Bjerring, Jens Christian, and Wolfgang Schwarz. "Granularity Problems." Philosophical Quarterly 67, no. 266 (2016): 22–37. http://dx.doi.org/10.1093/pq/pqw028.
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Dhanakodi.V, N.Balachandar, and M.Gayathri. "Power Quality Monitoring and Feedback Control for Hybrid Renewal Energy System using Meta Heuristic Optimization Technique." International Journal of Scientific Methods in Intelligence Engineering Networks 01, no. 04 (2023): 33–44. http://dx.doi.org/10.58599/ijsmien.2023.1404.
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Solar and wind energy are becoming more popular. Hybrid Renewable Energy System (HRES) is a fast-growing power industry segment. Power quality (PQ) issues have increased as renewable energy has increased in the electricity supply. This study will help electrical engineers identify power quality (PQ) disruptions from hybrid renewable power sources like solar and wind. The investigation will predict powergeneration-induced PQ problems. A self-contained Hybrid Renewable Energy System (HRES) is the project’s main goal. We will collect and analyses energy system data using Grey Wolf Optimization to improve mitigation and reduce PQ interruptions. The suggested technique analyses live data from several sources and historical data in many formats. To prevent problems, the hardware’s controllers will receive the data. Algorithms and designers will improve system efficiency and design ability. The monitoring system will predict PQ disturbances caused by electricity generation from different energy sources. The suggested device labels PQ disturbances by impact.
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Karthik, N., Shaik Abdul Gafoor, and M. Surya Kalavathi. "Classification of Power Quality Problems by Wavelet Fuzzy Expert System." Advanced Materials Research 463-464 (February 2012): 1573–78. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.1573.
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Electric power quality, which is a current interest to several power utilities all over the world, is often severely affected by harmonics and transient disturbances. There is no unique model which can assess the power quality problem and to identify and classify them properly. Existing automatic recognition methods need improvement in terms of their versatility, reliability, and accuracy. The FUZZY LOGIC based tools have been applied for the PQ classification. This paper addresses Power quality problem classification by wavelet and fuzzy expert system. Major Key issues and challenges related to these advanced techniques in automatic classification of PQ problems are highlighted. New intelligent system technologies using DSP, expert systems, AI and machine learning provide some unique advantages in intelligent classification of PQ distortions
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Mayyadah Sahib Ibrahim and Ali Sachit Kaittan. "Efficient Classification of Power Quality Using Long Short-Term Memory Network Technique." Proceedings of Engineering and Technology Innovation 29 (February 10, 2025): 26–46. https://doi.org/10.46604/peti.2024.13831.
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This study aims to apply a new deep-learning technique to detect and categorize individual and complex PQ issues such as swell, flickers, surges, interruptions, and sags. The suggested technique, the long short-term memory (LSTM) network, is a novel artificial intelligence technique and an identifiable form of recurrent neural network. This technique is utilized to detect and identify power quality (PQ) issues based on three principal solutions: automatic feature extraction, voltage/current magnitude calculations, and PQ problem duration. Simulated PQ problems generated by the Matlab simulation and many real field data sets are used to authorize the proposed technique's capability. The real data contain voltage and current waveforms that are measured, recorded, and analyzed in medium-voltage and high-voltage (MV/HV) substations by using a data acquisition device. The simulation results show that the proposed method is capable of detecting and classifying PQ problems more accurately compared with other artificial intelligence techniques.
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Mewes, Ricarda, Boris Friele, and Evert Bloemen. "Validation of the Protect Questionnaire: A tool to detect mental health problems in asylum seekers by non-health professionals." Torture Journal 28, no. 2 (2018): 56–71. http://dx.doi.org/10.7146/torture.v28i2.106884.
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Introduction: Prevalence rates of trauma-related mental disorders such as posttraumatic stress disorder (PTSD) or major depression (MD) are high in asylum seekers. The PROTECT Questionnaire (PQ) was designed to detect indications of those disorders in asylum seekers. Empirical data are needed to evaluate the PQ psychometrically. The objective of this study is to investigate the reliability, validity, sensitivity, and specificity of the PQ.
 Method: The PQ and validated questionnaires for PTSD (Posttraumatic Diagnostic Scale, PDS) and depression (Patient Health Questionnaire-9, PHQ- 9) were filled in by a sample of recently arrived asylum seekers in Germany (n=141). A sub-sample of 91 asylum seekers took part in a structured clinical interview to diagnose PTSD or MD (SCID-I).
 Results: The PQ showed a one-factor structure and good reliability (Cronbach’s ⍺= .82). It correlated highly with the PDS and the PHQ-9 (rs=.53-.77; ps≤.001). Diagnostic accuracy with regard to PTSD (AUC=.74; SE=.06; p<.001; 95%-CI=.63-.84) and MD (AUC=.72; SE=.06; p<.001; 95%-CI=.61- .83) was adequate, suggesting an optimal cut-off of 8 or 9. By categorizing participants into a low- and high-risk category, the PQ differentiated well between asylum seekers who fulfilled a PTSD or MD diagnosis and those who did not.
 Discussion: The results support the use of the PQ as a reliable and valid instrument for the purpose of detecting signs and symptoms of the two most common mental disorders in asylum seekers. Persons found to be at risk of mental disorders should be referred to a clinical diagnostic procedure.
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Jiang, Shulun, Jian Yang, and Di-an Fang. "Transcriptome changes of Takifugu obscurus liver after acute exposure to the oxygenated-PAH 9,10-phenanthrenequione." Physiological Genomics 52, no. 8 (2020): 305–13. http://dx.doi.org/10.1152/physiolgenomics.00022.2020.
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Contamination with polycyclic aromatic hydrocarbons (PAHs) causes noticeable ecological problems in aquatic ecosystems. 9,10-Phenanthrenequione (9,10-PQ) is an oxidized PAH and is highly toxic to aquatic animals. However, the effects of 9,10-PQ on the molecular metabolism of fish remain largely unknown. In this study, Takifugu obscurus juveniles were acutely exposed to 44.30 µg/L 9,10-PQ for 3 days. The transcriptome profile changes in their livers were compared between the 9,10-PQ treatment group and the control using T. rubripes as the reference genome. The results identified 22,414 genes in our transcriptome. Among them, 767 genes were differentially expressed after exposure to 9,10-PQ, which enriched 16 KEGG pathways. Among them, the glycolysis, phagosome, and FOXO signaling pathways were significantly activated in 9,10-PQ treatment compared with the control. These data indicate that 9,10-PQ increased the glycolysis capacity to produce more energy for resistance and harmed immune function. Moreover, several genes related to tumorigenesis were significantly upregulated in response to 9,10-PQ, displaying the carcinogenic toxicity of 9,10-PQ to T. obscurus. Genes in steroid biosynthesis pathways were downregulated in the 9,10-PQ treatment group, suggesting interference with the endocrine system. Overall, these findings provide information to help evaluate the environmental risks that oxygenated-PAHs present to T. obscurus.
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Devi, T. Anuradha, G. Srinivasa Rao, T. Anil Kumar, et al. "Hybrid optimal-FOPID based UPQC for reducing harmonics and compensate load power in renewable energy sources grid connected system." PLOS ONE 19, no. 5 (2024): e0300145. http://dx.doi.org/10.1371/journal.pone.0300145.
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Integration of renewable energy sources (RES) to the grid in today’s electrical system is being encouraged to meet the increase in demand of electrical power and also overcome the environmental related problems by reducing the usage of fossil fuels. Power Quality (PQ) is a critical problem that could have an effect on utilities and consumers. PQ issues in the modern electric power system were turned on by a linkage of RES, smart grid technologies and widespread usage of power electronics equipment. Unified Power Quality Conditioner (UPQC) is widely employed for solving issues with the distribution grid caused by anomalous voltage, current, or frequency. To enhance UPQC performance, Fractional Order Proportional Integral Derivative (FOPID) is developed; nevertheless, a number of tuning parameters restricts its performance. The best solution for the FOPID controller problem is found by using a Coati Optimization Algorithm (COA) and Osprey Optimization Algorithm (OOA) are combined to make a hybrid optimization CO-OA algorithm approach to mitigate these problems. This paper proposes an improved FOPID controller to reduce PQ problems while taking load power into account. In the suggested model, a RES is connected to the grid system to supply the necessary load demand during the PQ problems period. Through the use of an enhanced FOPID controller, both current and voltage PQ concerns are separately modified. The pulse signal of UPQC was done using the optimal controller, which analyzes the error value of reference value and actual value to generate pulses. The integrated design mitigates PQ issues in a system at non-linear load and linear load conditions. The proposed model provides THD of 12.15% and 0.82% at the sag period, 10.18% and 0.48% at the swell period, and 10.07% and 1.01% at the interruption period of non-linear load condition. A comparison between the FOPID controller and the traditional PI controller was additionally taken. The results showed that the recommended improved FOPID controller for UPQC has been successful in reducing the PQ challenges in the grid-connected RESs system.
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MANIMALA, K., K. SELVI, and R. AHILA. "POWER DISTURBANCES PATTERN RECOGNITION USING SUPPORT VECTOR MACHINE." International Journal of Information Acquisition 08, no. 01 (2011): 53–64. http://dx.doi.org/10.1142/s0219878911002331.
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Recently, many signal processing techniques, such as fast Fourier transform, short-time Fourier transform, wavelet transform (WT), and wavelet packet transform (WPT), have been applied to detect, identify, and classify power quality (PQ) disturbances. For research on PQ analysis, it is critical to apply the appropriate signal processing techniques and classifier to solve PQ problems. The aim of this paper is to develop a classification method based on the combination of Hilbert transform (HT) and support vector machine (SVM) for the assessment of power quality events. Recent data mining literature has shown that support vector machine methods generally outperform traditional statistical and neural methods in classification problems involving power disturbance signals. The features obtained from the Hilbert transform are distinct, understandable and immune to noise. Analysis is presented to verify that the merits of HT and SVM combination make it adequate for PQ analysis when compared with the existing techniques in the literature.
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Bläsius, Thomas, and Ignaz Rutter. "Simultaneous PQ-Ordering with Applications to Constrained Embedding Problems." ACM Transactions on Algorithms 12, no. 2 (2016): 1–46. http://dx.doi.org/10.1145/2738054.
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Kaleybar, Hamed Jafari, Morris Brenna, Federica Foiadelli, Seyed Saeed Fazel, and Dario Zaninelli. "Power Quality Phenomena in Electric Railway Power Supply Systems: An Exhaustive Framework and Classification." Energies 13, no. 24 (2020): 6662. http://dx.doi.org/10.3390/en13246662.
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Electric railway power systems (ERPS) as one of the most critical and high-power end-user loads of utility grids are characterized by outlandish power quality (PQ) problems all over the world. The extension and evolution of different supply topologies for these systems has resulted in significant and various forms of distortions in network voltage and current in all ERPS, the connected power system, and adjacent consumers. During the last years, numerous studies have been offered to investigate various aspects of PQs in a specific supplying topology. Variation in the supply structure of the ERPS and different types of locomotives has propelled the observation of different PQ phenomena. This versatility and development have led to confront considerable types of two-way interactive interfaces as well as reliability and PQ problems in ERPS. In addition, the lack of standards explicitly dedicated to ERPS has added to the ambiguity and complexity of this issue. In this paper, an extensive review of PQ distortions and phenomena in different configurations of ERPS is proposed and a systematic classification is presented. More than 140 scientific papers and publications are studied and categorized which can provide a fast review and a perfect perspective on the status of PQ indexes for researchers and experts.
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Aldosary, Abdallah. "Power Quality Conditioners-Based Fractional-Order PID Controllers Using Hybrid Jellyfish Search and Particle Swarm Algorithm for Power Quality Enhancement." Fractal and Fractional 8, no. 3 (2024): 140. http://dx.doi.org/10.3390/fractalfract8030140.
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Power quality (PQ) is a major issue in today’s electrical system that affects both utilities and customers. The proliferation of power electronics devices, smart grid technology, and renewable energy sources (RES) have all contributed to the emergence of PQ concerns in today’s power system. The Unified Power Quality Conditioner (UPQC) is a versatile tool that can be used to fix distribution grid issues caused by irregular voltage, current, or frequency. Several tuning parameters, however, restrict the effectiveness of the Fractional-Order Proportional Integral Derivative (FOPID) control technique, which is proposed to improve UPQC performance. To move beyond these restrictions and find the optimal solution for the FOPID controller problem, a hybrid optimization strategy called the Hybrid Jellyfish Search Optimizer and Particle Swarm Optimizer (HJSPSO) is employed. To meet the load requirement during PQ issue periods, the suggested model incorporates a renewable energy source into the grid system. Whether the load is linear or non-linear, the design maintains PQ problems to a minimum. Furthermore, the FOPID control technique is compared with other controllers. Results show that grid-connected RES systems using the proposed FOPID control approach for UPQC have fewer PQ problems. The presented UPQC with HJSPSO strategy significantly outperformed, with the shortest computing time of 127.474 s and an objective function value of 1.423.
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Khaleel, Mohamed. "Power Quality Enhancement Using Renewable Energy Sources and Electric Mobility." Brilliance: Research of Artificial Intelligence 3, no. 2 (2023): 306–15. http://dx.doi.org/10.47709/brilliance.v3i2.3252.
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In the present day, there is a growing emergence of obstacles pertaining to the remuneration of power quality (PQ) issues. In this context, the implementation of renewable energy sources (RES) solutions has a critical significance. The transition from traditional electrical power grids to smart grids necessitates the utilization of a significant quantity of power electronics converters and RES. These converters are essential for the incorporation of crucial technologies like renewable energies, electric mobility, and energy storage systems. Consequently, PQ concerns gain heightened significance in this context. The article focuses on elucidating the primary phenomena related to PQ issues in smart grids, their origins, and consequences across various sectors. Additionally, the paper provides a comprehensive examination and categorization of the primary PQ issues, along with their corresponding alignment with established standards. It also offers an assessment of PQ problems associated with RES and their integration with electric mobility.
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Bharatiraja, C., and Harish Chowdary V. "Real Time Power Quality Phenomenon for Various Distribution Feeders." Indonesian Journal of Electrical Engineering and Computer Science 3, no. 1 (2016): 10. http://dx.doi.org/10.11591/ijeecs.v3.i1.pp10-16.
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Power Quality (PQ) brings more challenges to the large- scale and medium scale industries because in the recent years most of them use high efficiency and low energy devices which cause vulnerable PQ disturbances at Point of Common Coupling (PCC). In this paper, the measurement at different times during load condition and analysis of all types of disturbances occurred has been done. When large rated equipments run, the disturbance (harmonics, RMS variations, and switching transients) levels are very high and poor power factor (PF) has also appeared. Due to this poor PF, reactive power consumption in load increases and accordingly total power increases. An electronic device such as LED lights, fluorescent lamps, computers, copy machines, and laser printers also disturb the supply voltage. We are very well known that every PQ problem directly or indirectly must affect economically. Many researchers have investigated PQ audit for over three decades. However these studies and analysis have been done only at simulation level. Hence, the PQ analyzer based study is required to find out the PQ issues at distribution feeders. It will be a valuable guide for researchers, who are interested in the domain of PQ and wish to explore the opportunities offered by these techniques for further improvement in the field of PQ. This paper gives a brief Real Time PQ measurement using PQ analyzer HIOKI PW3198 at Distribution Feeders and it gives an idea to the researcher to optimize problems-related to PQ with respect to the high rated and low rated electric machinery of different feeders at PCC level. This study further extends to analyze the grid disturbances and looks forward to the optimization methods for each individual PQ disturbance.
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Liubčuk, Vladislav, Virginijus Radziukynas, Gediminas Kairaitis, and Darius Naujokaitis. "Power Quality Impact and Its Assessment: A Review and A Survey of Lithuanian Industrial Companies." Inventions 10, no. 2 (2025): 30. https://doi.org/10.3390/inventions10020030.
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Poor PQ is a partial case of power system impact on society and the environment. Although the significance of good PQ is generally understood, the topic has not yet been sufficiently explored in the scientific literature. Firstly, this paper discusses the role of PQ in sustainable development by distinguishing economic, environmental, and social parts, including the existing PQ impact assessment methods. PQ problems must be studied through such prisms as financial losses of industrial companies, damage to end-use equipment, natural phenomena, interaction with animals, and social issues related to law, people’s well-being, health and safety. Secondly, this paper presents the results of the survey of Lithuanian industrial companies, which focuses on the assessment of industrial equipment immunity to both voltage sags and supply interruptions, as well as a unique methodology based on expert assessment, IEEE Std 1564-2014 and EN 50160:2010 voltage sag tables, matrix theory, a statistical hypothesis test, and convolution-based sample comparison that was developed for this purpose. The survey was carried out during the PQ monitoring campaign in the Lithuanian DSO grid, and is one of the few PQ surveys presented in the scientific literature. After counting the votes and introducing the rating system (with and without weights), the samples are compared both qualitatively and quantitatively in order to determine whether the PQ impact on various end-use equipment is similar or not.
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Ranjan, Ashish, and Jayanti Choudhary. "Meta-heuristic based power quality improvement in UPQC based grid-connected hybrid renewable energy system." Intellectual Journal of Energy Harvesting and Storage 2, no. 1 (2024): 14–29. https://doi.org/10.11591/ehs.v2i1.pp14-29.
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In recent days, the integration of the grid-connected load system with hybrid renewable energy system (HY-RES) to improve reliability and reduce losses are cheered. In order to satisfy the requirement of the load demand, the HY-RES is incorporated with the grid-connected load which leads to the power quality (PQ) problems in the system. Hence, the UPQC based HPSO-GWO are proposed in this paper. With the utilization of the UPQC device, the PQ issues are minimized by satisfy the load need in the HY-RES system to solve the PQ issues is the major goal of this work. To mitigate the PQ issues, the HPSO-GWO optimization algorithm with an inverter for SAPF and SH-APF is introduced to enhance the UPQC’s performance. HY-RES is originally built in this study with a PV system, WT, and BESS, all of which are connected to the load system. The load is connected to the system to produce PQ difficulties in order to examine the suggested technique's presentation. With the help of the HY-RES system, PQ problems are minimized and load demand is reimbursed. The proposed method has been implemented in the MATLAB/Simulink platform, and its results have been evaluated. In this paper, for validating the performance of the proposed technique, three various cases such as sag, swell, and fluctuation is analyzed. In addition, the total harmonic distortion (THD) is analyzed. Furthermore, the suggested strategy is compared to existing methods such as GWO and PSO algorithms to prove the proposed technique is superior to existing techniques.
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Alhaiz, Hussain A., Ahmed S. Alsafran, and Ali H. Almarhoon. "Single-Phase Microgrid Power Quality Enhancement Strategies: A Comprehensive Review." Energies 16, no. 14 (2023): 5576. http://dx.doi.org/10.3390/en16145576.
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Renewable distributed generators (RDGs) have made inroads in recent power systems owing to the environmental effect of traditional generators and their high consumption of electric energy. The widespread use of RDGs has been a recent trend in numerous nations. The integration complexity and the intermittent nature of RDGs can undermine the security and stability of microgrids (µGs). In order to guarantee the effectiveness, dependability, and quality of the electricity delivered, appropriate control methods are necessary. RDGs are being included in single-phase microgrids (1Ø-µGs) to generate energy closer to the user. The creation of low-voltage µGs allows for increased energy efficiency and improved electrical supply dependability. Nevertheless, the combined power pumped by DGs might create power quality (PQ) difficulties, especially during off-grid operations. The three biggest problems with PQ are reactive-power swapping, voltage and frequency (VαF) variations, and current and voltage (IαV) harmonic falsification associated with 1Ø-µGs; these conditions may affect the operation of µGs. The designed and implemented (primary–secondary control systems) in RDGs are the prevalent strategy discussed in the literature for mitigating these PQ difficulties. Furthermore, emerging grid innovations like the electrical spring offer viable alternatives that might reduce some problems through decentralized operation. Although several research studies have addressed PQ concerns in 3Ø-µGs, not all of these solutions are immediately applicable to their 1Ø equivalents. In this paper, the state of the art and a performance comparison of several PQ enhancement strategies of µGs is discussed. Additionally, the primary difficulties and several PQ approach tactics are highlighted. All vital features from high-quality published articles and new dimensions in this field are presented for mitigating PQ difficulties in 1Ø-µGs.
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Howell, Robert. "The Russellian Monist's Problems with Mental Causation." Philosophical Quarterly 65, no. 258 (2014): 22–39. http://dx.doi.org/10.1093/pq/pqu058.
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Ibrahim, Nagwa F., Abdulaziz Alkuhayli, Abderrahmane Beroual, Usama Khaled, and Mohamed Metwally Mahmoud. "Enhancing the Functionality of a Grid-Connected Photovoltaic System in a Distant Egyptian Region Using an Optimized Dynamic Voltage Restorer: Application of Artificial Rabbits Optimization." Sensors 23, no. 16 (2023): 7146. http://dx.doi.org/10.3390/s23167146.
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Photovoltaic (PV) systems are crucial to the production of electricity for a newly established community in Egypt, especially in grid-tied systems. Power quality (PQ) issues appear as a result of PV connection with the power grid (PG). PQ problems cause the PG to experience faults and harmonics, which affect consumers. A series compensator dynamic voltage restorer (DVR) is the most affordable option for resolving the abovementioned PQ problems. To address PQ difficulties, this paper describes a grid-tied PV combined with a DVR that uses a rotating dq reference frame (dqRF) controller. The main goal of this study is to apply and construct an effective PI controller for a DVR to mitigate PQ problems. The artificial rabbits optimization (ARO) is used to obtain the best tune of the PI controller. The obtained results are compared with five optimization techniques (L-SHADE, CMAES, WOA, PSO, and GWO) to show its impact and effectiveness. Additionally, Lyapunov’s function is used to analyze and evaluate the proposed controller stability. Also, a mathematical analysis of the investigated PV, boost converter, and rotating dqRF control is performed. Two fault test scenarios are examined to confirm the efficacy of the suggested control approach. The parameters’ (voltage, current, and power) waveforms for the suggested system are improved, and the system is kept running continuously under fault periods, which improves the performance of the system. Moreover, the findings demonstrate that the presented design successfully keeps the voltage at the required level with low THD% values at the load side according to the IEEE standards and displays a clear enhancement in voltage waveforms. The MATLAB/SIMULINK software is used to confirm the proposed system’s performance.
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Esmail, Yahia M., Ali H. Kasem Alaboudy, M. S. Hassan, and Gamal M. Dousoky. "Mitigating power quality disturbances in smart grid using FACTS." Indonesian Journal of Electrical Engineering and Computer Science 22, no. 3 (2021): 1223. http://dx.doi.org/10.11591/ijeecs.v22.i3.pp1223-1235.
Pełny tekst źródłaStreszczenie:
Power quality (PQ) assurance is a vital part of electrical distribution networks. There are many advantages and benefits of improving PQ, especially in the modern/smart grid. Smart grid (SG) has a lot of complicated and sensitive electrical components (non-linear loads) in addition to renewable energy systems (wind-solar) that may also be a source of PQ disturbances. PQ problems harm personal life and national production. Static synchronous compensator (STATCOM) and unified power quality conditioner (UPQC) are among the fastest response flexible alternating current transmission systems (FACTS) installed in smart grids to mitigate power quality disturbances such as voltage fluctuations, sag, swell, and harmonics. In this research, STATCOM and UPQC are designed and simulated in MATLAB/Simulink to overcome PQ-related disruptions in smart grids. Accordingly, the differences between the proposed two solutions are highlighted across this research and renewable energy sources' reliability during faults. Therefore, the reader will be able to choose the appropriate FACTS devices. This study emphasizes the extent of the smart grid need for the FACTS. As per the given results of this study, STATCOM and UPQC have shown exemplary performance in the PQ improvement investigations conducted in the context of smart/modern grids.
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Obiora, Gerard N., Festus O. Oghenegweke, Godwin O. Igbinosa, Tobenn Obidire, Collins B. Fiemobebefa, and Oluwaseun A. Bamido. "Reduction of Power Quality Perturbations: A Review." European Journal of Applied Science, Engineering and Technology 3, no. 3 (2025): 174–90. https://doi.org/10.59324/ejaset.2025.3(3).11.
Pełny tekst źródłaStreszczenie:
Power is usually generated by various power plants and transmitted at high voltages to the end users. This is made possible through a sophisticated network of diverse components utilized in a given power system. Also, every day, domestic and commercial activities such as cooking, transportation, manufacturing, illumination of offices and homes, air conditioning, refrigeration, and the likes, makes use of electricity. It is thus impossible that the power quality (PQ) will remain the same given that most components utilized across these processes are mostly and highly non-linear in nature. What this implies is that there will always be power quality problems, and these issues cannot be totally eliminated but can be effectively reduced. In this study, firstly, the various PQ problems were categorized accordingly and their overview given. Then, the causes and effects of these issues were succinctly listed and lastly, the ways of reducing PQ perturbations were given. Industry experts, other researchers and enthusiasts will find this study very useful.
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Vedant, S. Samudre*. "POWER QUALITY STANDARDS, PROBLEMS AND THEIR SOLUTIONS." INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY 5, no. 12 (2016): 219–27. https://doi.org/10.5281/zenodo.192584.
Pełny tekst źródłaStreszczenie:
Power quality is one of the major concerns and emerging issues in the present era. With increasing quantities of non-linear loads being added to electrical systems, it has become necessary to investigate the power quality issues as all electrical devices are prone to failure when exposed to one or more power quality problems. This paper highlights power quality problems, effect of power quality problems in different apparatuses and methods for its correction. This paper will be very much helpful for engineers, technicians, designers, researchers and system operators as it is necessary for them to become familiar with power quality issues.
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Esmail, Yahia M., Ali H. Kasem Alaboudy, M. S. Hassan, and Gamal M. Dousoky. "Mitigating power quality disturbances in smart grid using FACTS." Indonesian Journal of Electrical Engineering and Computer Science 22, no. 3 (2021): 1223–35. https://doi.org/10.11591/ijeecs.v22.i3.pp1223-1235.
Pełny tekst źródłaStreszczenie:
Power quality (PQ) assurance is a vital part of electrical distribution networks. There are many advantages and benefits of improving PQ, especially in the modern/smart grid. Smart grid (SG) has a lot of complicated and sensitive electrical components (non-linear loads) in addition to renewable energy systems (wind-solar) that may also be a source of PQ disturbances. PQ problems harm personal life and national production. Static synchronous compensator (STATCOM) and unified power quality conditioner (UPQC) are among the fastest response flexible alternating current transmission systems (FACTS) installed in smart grids to mitigate power quality disturbances such as voltage fluctuations, sag, swell, and harmonics. In this research, STATCOM and UPQC are designed and simulated in MATLAB/Simulink to overcome PQ-related disruptions in smart grids. Accordingly, the differences between the proposed two solutions are highlighted across this research and renewable energy sources' reliability during faults. Therefore, the reader will be able to choose the appropriate FACTS devices. This study emphasizes the extent of the smart grid need for the FACTS. As per the given results of this study, STATCOM and UPQC have shown exemplary performance in the PQ improvement investigations conducted in the context of smart/modern grids.
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Obiora, Gerard N., Festus O. Oghenegweke, Godwin O. Igbinosa, Tobenn Obidire, Collins B. Fiemobebefa, and Oluwaseun A. Bamido. "Reduction of Power Quality Perturbations: A Review." European Journal of Applied Science, Engineering and Technology 3, no. 3 (2025): 174–90. https://doi.org/10.59324/ejaset.2025.3(3).11.
Pełny tekst źródłaStreszczenie:
Power is usually generated by various power plants and transmitted at high voltages to the end users. This is made possible through a sophisticated network of diverse components utilized in a given power system. Also, every day, domestic and commercial activities such as cooking, transportation, manufacturing, illumination of offices and homes, air conditioning, refrigeration, and the likes, makes use of electricity. It is thus impossible that the power quality (PQ) will remain the same given that most components utilized across these processes are mostly and highly non-linear in nature. What this implies is that there will always be power quality problems, and these issues cannot be totally eliminated but can be effectively reduced. In this study, firstly, the various PQ problems were categorized accordingly and their overview given. Then, the causes and effects of these issues were succinctly listed and lastly, the ways of reducing PQ perturbations were given. Industry experts, other researchers and enthusiasts will find this study very useful.
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Guivant, Jose, Brett Seton, and Mark Whitty. "2D Path Planning Based on Dijkstra's Algorithm and Pseudo Priority Queues." Proceedings of the International Symposium on Combinatorial Search 3, no. 1 (2021): 206. http://dx.doi.org/10.1609/socs.v3i1.18255.
Pełny tekst źródłaStreszczenie:
This paper presents the application of the PPQ Dijkstra approach for solving 2D path planning problems. The approach is a Dijkstra process whose priority queue (PQ) is implemented through a Pseudo Priority Queue (PPQ) also known as Untidy PQ. The performance of the optimization process is dramatically improved by the application of the PPQ. This modification can be used for a family of problems. The path planning problem belongs to the family of feasible problems that can be solved by considering PPQ-Dijkstra approach. The solution provided by the PPQ-Dijkstra algorithm is optimal, i.e. it is identical to the solution obtained through the standard Dijkstra algorithm. The PPQ-Dijkstra algorithm can be also applied for higher dimensionality problems such as non-holonomic planning processes, e.g. involving configuration spaces of higher dimension.
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Wei, Tian Cai, Shun Tao, Bin Su, and Chao Luo. "Current Detection Method and its Application of an Extension pq Theory." Applied Mechanics and Materials 668-669 (October 2014): 907–10. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.907.
Pełny tekst źródłaStreszczenie:
In the modern society, with the rapid development of industrial technology and information industry, electrical loads become more and more complex. As a result, the harmonics and reactive power problems have become increasingly serious. In the non-sinusoidal conditions, conventional power definitions don’t work well any more. Power theory is one of the foundations of financial accounts for energy, evaluation of the efficiency of power transmission and control of current compensation. Among them, the instantaneous reactive power theory is regarded as one of the most promising power theories. What’s more, it has been improved. Based on the three-phase three-wire system and four kinds of different supply voltage conditions, this paper compares the instantaneous reactive power theory (pq theory) with the extension pq theory. At last, the simulation results are presented. As a conclusion, the extension pq theory is the improvement of the pq theory and has a wider applicability.
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DU, GAO-XIANG, HAO HE, LI-BING LIAO, and LI-JUAN WANG. "MECHANO-CHEMICAL PREPARATION OF POWDER QUARTZ/TiO2 COMPOSITE PARTICLES." Surface Review and Letters 20, no. 02 (2013): 1350016. http://dx.doi.org/10.1142/s0218625x13500169.
Pełny tekst źródłaStreszczenie:
Titanium dioxide pigment is a white pigment of high performance. However, its production could cause severe environmental and resource problems. In this paper, powder quartz/ TiO2 composite particles (PQ/TCP), a type of core (powder quartz)–shell( TiO2 ) composite powder, were prepared by a mechano-chemical method. The pigment properties of PQ/TCP and the mechanism of the mechano-chemical reaction between quartz and TiO2 were investigated. Orthogonal analyses of experimental vairables showed optimal pigment characteristics of PQ/TCP under the following conditions: 4 h of activation for powder quartz, mixing/grinding at 1000 rpm for 1 h, with a mixing slurry made of 50% powder quartz and 0.4% dispersant. Powder quartz was evenly coated by TiO2 and the Si–O–Ti bond was formed between powder quartz and TiO2 in PQ/TCP as revealed by FTIR analyses and confirmed by surface thermodynamic calculation.
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Rajender, Kumar Beniwal1 Akanksha Aggarwal *1 Rohit Saini2 Sunita Saini3. "ANALYSIS OF ELECTRICITY SUPPLY IN THE DISTRIBUTION NETWORK OF POWER SECTOR." INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY 7, no. 2 (2018): 404–12. https://doi.org/10.5281/zenodo.1173535.
Pełny tekst źródłaStreszczenie:
Nowadays, consumers of electricity are demanding for better quality of services and this creates competition in power utility companies to provide better services which are reliable as well as efficient and less costly also to their consumers. Assessment of PQ problems is a tedious task and the various aspects of power system and equipment modelling, disturbance mitigation and data analysis are involved in it. The majority of the work is focused on the distribution system where the sensitive equipments experience interference under different kinds of power disturbances from the system and the local network. For the effective mitigation of these disturbances, some knowledge about PQ events and its effects on equipment is important. So, in this concern PQ is a challenging issue in current scenario. The main aim of this review paper is to investigate different techniques reported by the researchers for detection and classification of PQ events.
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Cahill, Kevin. "The Nature of Philosophical Problems: Their Causes and Implications." Philosophical Quarterly 66, no. 263 (2015): 406–8. http://dx.doi.org/10.1093/pq/pqv054.
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Chilakapati, Lenin Babu, and T. Gowri Manohar. "Power Quality Enhancement in a Grid-Integrated Solar-PV System with a Hybrid UPQC Control Strategy." Solar Energy and Sustainable Development Journal 13, no. 2 (2024): 120–37. http://dx.doi.org/10.51646/jsesd.v13i2.220.
Pełny tekst źródłaStreszczenie:
The supply grid network has been periodically experiencing frequent problems with Power Quality (PQ), and these problems have gotten worse over time due to the rise of electrical appliances. Thus, supplying consumers with electricity in the custom of sinusoidal voltages and currents that have adequate magnitudes and frequencies near the common point of coupling (PCC) stays one of the Utility system's main responsibilities. Thus, in order to improve PQ in the supply grid network, this article examines the practice of solar-PV coordinated Unified Power Quality Conditioner (UPQC). By means of optimizing the utilization of solar energy and improving PQ, the Solar-PV fed UPQC contributes clean, renewable energy to the grid and solves environmental problems at the same time. This study presents Adaptive Leaky Least Mean Square (AL_LMS) algorithm-based control techniques for UPQC, which include both traditional Proportional-Integral (PI) and Adaptive Neuro Fuzzy Inference System (ANFIS) controllers for UPQC series and shunt active converter switching. This method gets the reference signals with switching on the shunt and series voltage source converters (VSCs) of UPQC by means of iteratively updation of the weights. Accordingly, PQ consternations for instance, voltage sag and swell of load voltage and harmonic distortions of grid current are reduced when control techniques have been applied to solar-PV fed UPQC. This work is carried out in MATLAB/Simulation software, and also the results of simulations demonstrate that the suggested ANFIS controlled AL_LMS algorithm is the most effective at improving power quality while adhering to IEEE-519 Standards when applied to a solar-PV fed UPQC.
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Reddy, Ch Rami, B. Srikanth Goud, Flah Aymen, Gundala Srinivasa Rao, and Edson C. Bortoni. "Power Quality Improvement in HRES Grid Connected System with FOPID Based Atom Search Optimization Technique." Energies 14, no. 18 (2021): 5812. http://dx.doi.org/10.3390/en14185812.
Pełny tekst źródłaStreszczenie:
An intelligent control strategy is proposed in this paper which suggests the Optimum Power Quality Enhancement (OPQE) of grid-connected hybrid power systems with solar photovoltaic, wind turbines, and battery storage. Unified Power Quality Conditioner with Active and Reactive power (UPQC-PQ) is designed with Atom Search Optimization (ASO) based Fractional-order Proportional Integral Derivative (FOPID) controller in the proposed Hybrid Renewable Energy Sources (HRES) system. The main aim is to regulate voltage while reducing power loss and reducing Total Harmonic Distortion (THD). UPQC-PQ is used to mitigate the Power Quality (PQ) problems such as sag, swell, interruptions, real power, reactive power and THD reductions related to voltage/current by using ASO based FOPID controller. The developed technique is demonstrated in various modes: simultaneous to improve PQ reinforcement and RES power injection, PRES > 0, PRES = 0. The results are then compared to those obtained using previous literature methods such as PI controller, GSA, BBO, GWO, ESA, RFA, and GA and found the proposed approach is efficient. The MATLAB/Simulink work framework is used to create the model.
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Gamasu, Ramesh. "Load flow Pseudo-inverse and Magnitude Conversions for Mitigation of PQ Problems using DVR." International Journal of Advanced Science and Technology 60 (November 30, 2013): 9–24. http://dx.doi.org/10.14257/ijast.2013.60.02.
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Gade, Swati, Rahul Agrawal, and Ravindra Munje. "Recent Trends in Power Quality Improvement: Review of the Unified Power Quality Conditioner." ECTI Transactions on Electrical Engineering, Electronics, and Communications 19, no. 3 (2021): 268–88. http://dx.doi.org/10.37936/ecti-eec.2021193.244936.
Pełny tekst źródłaStreszczenie:
The electrical power sector is currently focusing on power quality (PQ) issues and their mitigation. Industrial automation and the use of power electronic converters for the integration of distributed generation create various PQ problems. This necessitates PQ enhancement, which in turn helps to improve the life span of the equipment as well as the reliability of supply for feeding critical loads within the system. This paper presents a comprehensive review of the Unified Power Quality Conditioner (UPQC) and its widespread application in the distribution system. The UPQC belongs to the family of active power filters. It contributes to the alleviation of voltage and current-related PQ issues along with power factor correction and the integration of renewable energy systems in the distribution network. This paper discusses various topologies, compensation methods, control theories, and the technological developments in recent years. More than 160 research papers have summarized the features of UPQC for further applications. Based on the outcomes of the investigation, the future direction of the UPQC is discussed. This paper is expected to play a major role in guiding research scholars in the application of the UPQC.
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DEKHANDJI, Fatma Zohra, Salim TALHAOUI, and Youcef ARKAB. "Power Quality Detection, Classification and Monitoring Using LABVIEW." Algerian Journal of Signals and Systems 4, no. 2 (2019): 101–11. http://dx.doi.org/10.51485/ajss.v4i2.86.
Pełny tekst źródłaStreszczenie:
In recent years, Power Quality becomes increasingly a major concern for both electric utilities and end users. Accordingly, the electrical engineering community has to deal with the analysis, diagnosis and solution of PQ issues using system approach rather than handling these issues as individual problems. This paper describes the analysis of PQ using advanced signal processing tools represented in Hilbert & Wavelet Transforms (HT-WT) and artificial intelligence tools represented in Artificial Neural Network & Support Vector Machine (ANN-SVM) for detection and classification of power quality disturbances respectively. These techniques were successfully simulated using LABVIEW software capabilities. The results of simulation indicate that the signal processing techniques are effective mechanisms to detect and classify power quality disturbances. At the end, the combination of WT as a tool of detection and features extraction with SVM as a classifier tool resulted as the best combination for PQ monitoring system.
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Singh, Pradeep, Krishan Arora, and Umesh C. Rathore. "Control Strategies for Improvement of Power Quality in Grid Connected Variable Speed WECS with DFIG – An Overview." Journal of Physics: Conference Series 2327, no. 1 (2022): 012008. http://dx.doi.org/10.1088/1742-6596/2327/1/012008.
Pełny tekst źródłaStreszczenie:
Abstract The presented paper gives a detailed observation of the PQ related problems for WE based on the EFIG or DFIG (Extra or Doubly Fed Induction Generator. Fundamental Frequency Components are the most typical reasons of disruption of power quality. On the other hand, wind loading conditions also disrupt the power quality. Numerous modes for the removing of these problems were studied to get the rid of these fundamental frequency components of the WES (Wind Energy Systems). In the presented paper, there is substantial analysis of numerous controlling techniques were presented to eliminate these PQ and different loading conditions i.e. grid conditions and wind loading conditions. Furthermore, utilizing the WECS (Wind Energy Conversion System) as an operative filter. This analysis of DFIG based WECS help research scholars to choose the adequate control procedures while utilizing the WECS as an operative filter.
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Arov, D. Z., B. Fritzsche, and B. Kirstein. "On Some Completion Problems for Various Subclasses of $j_{pq}$-inner Functions." Zeitschrift für Analysis und ihre Anwendungen 11, no. 4 (1992): 489–508. http://dx.doi.org/10.4171/zaa/589.
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Hosokawa, Takafumi, Tsuyoshi Tajika, Morimichi Suto, and Hirotaka Chikuda. "Surgical Treatment of Distal Radius Fractures Complicated by Concomitant Flexor Carpi Radialis Brevis: A Case Series and Surgical Techniques." Journal of Orthopaedic Case Reports 13, no. 11 (2023): 18–23. http://dx.doi.org/10.13107/jocr.2023.v13.i11.3990.
Pełny tekst źródłaStreszczenie:
Introduction: The flexor carpi radialis brevis (FCRB) is a rare anatomical variation, with a reported prevalence ranging from 0.9% to 8.7%. Our previous report showed three cases of FCRB in distal radius fracture (DRF) and found that hypoplastic pronator quadratus (PQ) adjacent to the FCRB muscle made it difficult to cover a volar locking plate (VLP). As we subsequently experienced additional six FCRBs, we report on new findings and surgical tips. Case Report: VLP fixation was performed on DRF with FCRB in nine limbs of eight patients. The prevalence was 2.9% (9 of 310 limbs). Of the seven patients that underwent unilateral surgery, six were muscle type and one was tendon type. One patient who underwent bilateral surgery had a muscle type on the left and a tendon type on the right. In three muscle types, as the FCRB muscle belly was widely attached to the radial side of the radius and the radial side of the PQ was hypoplastic, postoperative covering of the plate by repair of the PQ was impossible. Then, in two of those cases, the PQ and FCRB were sutured and the plate was covered. FCRB muscle could be retracted to the radial side in all cases. One patient with a tendon type had a ruptured tendon, which was left unrepaired. All patients had no postoperative problems. Conclusion: In the muscle-type FCRB, the muscle should be retracted to the radial side for VLP fixation. The muscle belly might occupy the radial side of the radius, and the PQ might be hypoplastic and unrepairable. However, the plate can be covered by suturing the PQ and FCRB. Keywords: Flexor carpi radialis brevis, distal radius fracture, hypoplastic pronator quadratus.
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Prasad, Devalraju, and C. Dhanamjayulu. "A Review of Control Techniques and Energy Storage for Inverter-Based Dynamic Voltage Restorer in Grid-Integrated Renewable Sources." Mathematical Problems in Engineering 2022 (September 29, 2022): 1–43. http://dx.doi.org/10.1155/2022/6389132.
Pełny tekst źródłaStreszczenie:
Power quality (PQ) is a key issue, particularly for technologically advanced process equipment, whose performance mainly depends on the quality of supply. Problems with PQ such as voltage swells/sags, interruptions, and harmonics are defined by any voltage, current, or frequency abnormalities causing damage or failure of the end-user equipment. Outages and interruptions lead to malfunctioning of end-user equipment or sensitive loads, such as diagnostic equipment in healthcare facilities, clinics, educational institutions, and detention centers, while further increasing significant economic losses. Custom power devices (CPDs) are recommended for enhancing power quality, and the best and most economical solution is considered to be the dynamic voltage restorer (DVR). Several methods are suggested to improve the PQ by using the dynamic voltage restorer; among them, most encouraging ways are to use a multilevel inverter (MLI) in the dynamic voltage restorer. This article combines the latest work of the literature, as well as a detailed discussion on PQ issues of the grid-integrated renewable energy sources (RESs), DVR principle with its operating procedures, system components, energy storage-based DVR topologies, DVR control unit, and DVR power converter-based topologies. In addition, synthesis of energy storage, control strategies, and multilevel inverters for DVR. This review benefits those interested in investigating DVR as a relevant and comprehensive reference.
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Tzinman, Rina. "Thinking Parts and Embodiment." Philosophical Quarterly 71, no. 1 (2020): 163–82. http://dx.doi.org/10.1093/pq/pqaa020.
Pełny tekst źródłaStreszczenie:
Abstract According to the thinking parts problem, any part sufficient for thought—e.g. a head—is a good candidate for being a thinker, and therefore being us. So we can’t assume that we—thinkers—are (or are constituted by) human beings rather than their proper parts. Many solutions to this problem have been proposed. However, I will show that the views currently on the market all face serious problems. I will then offer a new solution that avoids these problems. The thinking parts problem arises from considerations that seem to be empirically substantiated. One virtue of my solution is that in addition to its theoretical apparatus it appeals to empirically substantiated considerations.
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Ehtesham, Mohammad, and Md Junaid. "Advanced compensation scheme for enhancing photovoltaic power quality." Indonesian Journal of Electrical Engineering and Computer Science 27, no. 3 (2022): 1223. http://dx.doi.org/10.11591/ijeecs.v27.i3.pp1223-1230.
Pełny tekst źródłaStreszczenie:
With the photovoltaic (PV) system becoming highly popular in distribution network, there is also a growing concern regarding its adverse impacts over the power quality (PQ) of integrated system. This deterioration in PQ hassparked a new interest in the filtering techniques used in the power systemfor mitigating these problems. In contrast to conventional passive filters now active power filters (APFs) are being looked as the predominant solution.This paper presents a state-estimation based effective compensation strategy for enhancing performance of employed APF scheme. A novel control technique for PQ enhancement is proposed where Kalman filtering approach has been applied for generating the reference signals. Also, an adaptive hysteresis band technique has been applied here in the switching strategy. Thus an enhanced filter performance is achieved with reduced complexity and better elimination of distortions. Simulated results obtained in MATLAB/Simulink platform have been analyzed completely, where the superiority of filtering algorithm has been also demonstrated through leasttotal harmonic distortion (THD) achieved in source current among all the existing Kalman filters.
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Mattar, El-Zahraa M., Ekramy S. Mahmoud, and Mohammed Ibrahim El-Sayed. "Mitigation of voltage sag and voltage swell by using dynamic voltage restorer." International Journal of Power Electronics and Drive Systems (IJPEDS) 15, no. 2 (2024): 1290. http://dx.doi.org/10.11591/ijpeds.v15.i2.pp1290-1299.
Pełny tekst źródłaStreszczenie:
Recent power quality (PQ) research shows that the most common types of power quality disturbances are voltage sags and swells in medium and low-voltage distribution grids. This paper shows how to improve two significant power quality disturbances: sags and swells voltage. To find out what effect these two PQ issues have in real life, a study case based on real nonlinear loads data from large induction motors at Beshai Company in Sadat City in Egypt is investigated. The dynamic voltage restorer (DVR) has been suggested as a solution to the voltage swell and voltage sag issues. The point of common coupling (PCC) is linked with the dynamic voltage restorer to mitigate the PQ problems that have been found. The power network, loads, and DVR may all be modeled using the MATLAB/Simulink platform. The jellyfish search optimizer (JFS) is used to get the gain settings of the proportional and integral (PI) controller for the proposed DVR. MATLAB/Simulink's results show that the proposed device is effective, reliable, and has low latency.
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Ehtesham, Mohammad, and Mohammad Junaid. "Advanced compensation scheme for enhancing photovoltaic power quality." Indonesian Journal of Electrical Engineering and Computer Science 27, no. 3 (2022): 1223–30. https://doi.org/10.11591/ijeecs.v27.i3.pp1223-1230.
Pełny tekst źródłaStreszczenie:
With the photovoltaic (PV) system becoming highly popular in distribution network, there is also a growing concern regarding its adverse impacts over the power quality (PQ) of integrated system. This deterioration in PQ has sparked a new interest in the filtering techniques used in the power system for mitigating these problems. In contrast to conventional passive filters now active power filters (APFs) are being looked as the predominant solution. This paper presents a state-estimation based effective compensation strategy for enhancing performance of employed APF scheme. A novel control technique for PQ enhancement is proposed where Kalman filtering approach has been applied for generating the reference signals. Also, an adaptive hysteresis band technique has been applied here in the switching strategy. Thus an enhanced filter performance is achieved with reduced complexity and better elimination of distortions. Simulated results obtained in MATLAB/Simulink platform have been analyzed completely, where the superiority of filtering algorithm has been also demonstrated through least total harmonic distortion (THD) achieved in source current among all the existing Kalman filters.
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Mattar, El-Zahraa M., Ekramy S. Mahmoud, and Mohamed I. El-Sayed. "Mitigation of voltage sag and voltage swell by using dynamic voltage restorer." International Journal of Power Electronics and Drive Systems (IJPEDS) 15, no. 2 (2024): 1290–99. https://doi.org/10.11591/ijpeds.v15.i2.pp1290-1299.
Pełny tekst źródłaStreszczenie:
Recent power quality (PQ) research shows that the most common types of power quality disturbances are voltage sags and swells in medium and low-voltage distribution grids. This paper shows how to improve two significant power quality disturbances: sags and swells voltage. To find out what effect these two PQ issues have in real life, a study case based on real nonlinear loads data from large induction motors at Beshai Company in Sadat City in Egypt is investigated. The dynamic voltage restorer (DVR) has been suggested as a solution to the voltage swell and voltage sag issues. The point of common coupling (PCC) is linked with the dynamic voltage restorer to mitigate the PQ problems that have been found. The power network, loads, and DVR may all be modeled using the MATLAB/Simulink platform. The jellyfish search optimizer (JFS) is used to get the gain settings of the proportional and integral (PI) controller for the proposed DVR. MATLAB/Simulink's results show that the proposed device is effective, reliable, and has low latency.
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Chilakapati, Lenin Babu, and T. Gowri Manohar. "Control Strategies for Enhancing Power Quality with Unified Power Quality Conditioner in a Solar-PV Integrated Utility System." International Journal of Experimental Research and Review 35 (November 30, 2023): 1–15. http://dx.doi.org/10.52756/ijerr.2023.v35spl.001.
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The electrical utility systems are well-liked as local energy systems because of their capacity to incorporate renewable energy, enhance energy effectiveness and strengthen the resilience of the power system. These benefits do, however, come with specific complications regarding control and power quality (PQ). PQ within a utility system is paramount to ensure the appropriate operation of connected devices and the well-being of the overall system. As a result, both voltage quality & current quality are significant. Control strategies in conjunction with cutting-edge power electronics devices (PED) offer a solid framework to handle PQ challenges. Hence, this paper’s proposed work discusses the application of a Solar-Photovoltaic (PV) fed Unified Power Quality Conditioner (UPQC) for power quality enhancement towards the supply grid network. The Solar-PV fed UPQC enhances PQ and maximizes solar energy utilisation, leading to an eco-friendly and cost-effective solution while injecting clean, renewable energy into the grid. In this paper, the control strategies for UPQC are based primarily on the Adaptive Leaky Least Mean Square (AL_LMS) algorithm as compared with the Synchronous Reference Frame (SRF) based theory for switching of series and shunt active converters of UPQC. This AL_LMS approach extracts reference signals to switch UPQC’s shunt and series voltage source converters (VSCs) by iteratively updating the weights. Thus, the control strategy applied to Solar-PV fed UPQC mitigates voltage problems like voltage sag and swell, current harmonic distortions and other PQ issues. The work is done in MATLAB/ Simulation software and simulation outcomes show the effectiveness of Solar-PV fed UPQC in improving power quality by maintaining within the IEEE-519 Standards.