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Journal articles on the topic 'Switching overvoltage'
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1
Keitoue, Samir, Ivan Murat, Božidar Filipović-Grčić, Alan Župan, Ivana Damjanović, and Ivica Pavić. "Lightning caused overvoltages on power transformers recorded by on-line transient overvoltage monitoring system." Journal of Energy - Energija 67, no. 2 (2022): 44–53. http://dx.doi.org/10.37798/201867279.
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Transient overvoltages generated by lightning strikes or switching operations represent a significant risk to bushings and windings of power transformers. They cause stress on the insulation system and can, over time, cause dielectric failure and damage to power transformers. Many transformer failures are reported as dielectric failures and they are not necessarily linked to any particular event when they occur but may be the result of prior damage from transient overvoltage events. Lightning and switching overvoltage waveforms appearing at transformer terminals in real operating conditions may significantly differ from standard impulse voltage waveforms used during laboratory testing. The number and amplitudes of overvoltages which stress the insulation depend on various parameters such as the lightning strike density in the considered area, since it determines how often the transformer is stressed by lightning overvoltages. Since the overvoltage amplitudes at transformer terminals are usually unknown, an on-line overvoltage transient recorder can be used with the ability to sample, analyse and store transients in real-time. In this paper, an on-line transient overvoltage monitoring system (TOMS) for power transformers is presented that is capable to continuously record in real-time various kinds of transient overvoltages such as lightning or switching overvoltages. Special attention is paid to lightning caused transient overvoltages recorded at the terminals of 150 MVA power transformer. Recorded waveforms originating from lightning strikes to overhead lines are correlated with data from the lightning location system (LLS) and supervisory control and data acquisition (SCADA) system. Collected data about overvoltage stresses can be used as the basis for the assessment of the transformer insulation condition, estimation of health index and for analysis of various kinds of events such as faults or equipment failures.
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Furgał, Jakub, Maciej Kuniewski, and Piotr Pająk. "Analysis of Internal Overvoltages in Transformer Windings during Transients in Electrical Networks." Energies 13, no. 10 (2020): 2644. http://dx.doi.org/10.3390/en13102644.
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Due to the increasing requirements for the reliability of electrical power supply and associated apparatus, it is necessary to provide a detailed analysis of the overvoltage risk of power transformer insulation systems and equipment connected to their terminals. Exposure of transformer windings to overvoltages is the result of the propagation condition of electromagnetic waves in electrical networks and transformer windings. An analysis of transformer winding responses to transients in power systems is of particular importance, especially when protection against surges by typical overvoltage protection systems is applied. The analysis of internal overvoltages in transformers during a typical transient related to switching operations and selected failures is of great importance, particularly to assess the overvoltage exposure of insulation systems in operating conditions. The random nature of overvoltage phenomena in electrical networks implies the usage of computer simulations for the analysis of overvoltage exposures of electrical devices in operation. This article presents the analysis of the impact of transient phenomena in a model of a medium-voltage electrical network during switching operations and ground faults on overvoltages in the internal insulation systems of transformer windings. The basis of the analysis is simulations of overvoltages in the windings, made in the Electromagnetic Transients Program/Alternative Transients Program (EMTP/ATP) using a model with lumped parameters of transformer windings. The analysis covers the impact of the cable line length and the ground fault resistance value on internal overvoltage distributions.
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Al-Tak, Mazyed A., Mohd Fadzil Ain, Omar Sh Al-Yozbaky, and Mohamad Kamarol Mohd Jamil. "Effect of shunt reactor rating on the switching transients overvoltage in high voltage system." Bulletin of Electrical Engineering and Informatics 13, no. 1 (2024): 38–49. http://dx.doi.org/10.11591/eei.v13i1.6100.
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This paper includes a computer simulation of switching transient overvoltages during the disconnecting of shunt reactors (SR). Based on the results of the transient simulations, two reactors (150 MVAr and 50 MVAr) were examined. Reactor current interruption causes significant overvoltages, especially across the reactor and the circuit breaker (CB). The severity of these overvoltages may surpass the voltage level, which might endanger the reactor’s insulation and accelerate the CBs ageing process. For this reason, a significantly modified circuit model is proposed. The results of the field testing showed that the proposed modified circuit technique was successful. The transient overvoltages were computed using ATP-draw simulations of the equivalent circuit during switching. Successful synchronous switching could decrease the electromagnetic and mechanical stress generated during frequent switching operations. The model was examined the switching transient overvoltage for different values of current chopping (0-20) A. The proposed model proved that the reduction of the overvoltage was 86% in case of (50 MVAr) shunt reactor rating and 87% in case of (150 MVAr) shunt reactor rating.
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Zhang, Wen, Zhe Yu Zhang, Fred Wang, Leon M. Tolbert, Daniel Costinett, and Benjamin Blalock. "Characterization and Modeling of a SiC MOSFET’s Turn-Off Overvoltage." Materials Science Forum 924 (June 2018): 827–31. http://dx.doi.org/10.4028/www.scientific.net/msf.924.827.
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The overvoltage during hard switching limits the full utilization of devices due to higher blocking voltage requirement. The faster switching speed of SiC MOSFET worsens the trade-off, and the understanding of the overvoltage’s mechanism is crucial for the better utilization. In this paper, experimental characterizations on the influence of circuit parasitic parameters and gate resistances on overvoltage are performed. Furthermore, a SPICE-based device behavioral model is built and found to able to accurately predict the overvoltage. The same method could be applied to device rating selection in converter design.
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Florkowski, Marek, Jakub Furgał, Maciej Kuniewski, and Piotr Pająk. "Overvoltage Impact on Internal Insulation Systems of Transformers in Electrical Networks with Vacuum Circuit Breakers." Energies 13, no. 23 (2020): 6380. http://dx.doi.org/10.3390/en13236380.
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Vacuum circuit breakers are increasingly used as switching apparatus in electric power systems. The vacuum circuit breakers (VCBs) have very good operating properties. VCBs are characterized by specific physical phenomena that affect overvoltage exposure of the insulation systems of other devices. The most important phenomena are the ability to chop the current before the natural zero crossing, the ability to switch off high-frequency currents, and the rapid increase in dielectric strength recovery. One of the devices connected directly to vacuum circuit breakers is the distribution transformer. Overvoltages generated in electrical systems during switching off the transformers are a source of internal overvoltages in the windings. The analysis of the exposure of transformers operating in electrical networks equipped with vacuum circuit breakers is of great importance because of the impact on the insulation systems of switching overvoltages (SO). These types of overvoltages can be characterized by high maximum values and atypical waveforms, depending on the phenomena in the circuit breaker chambers, system configuration, parameters of electrical devices, and overvoltage protection. Overvoltages that stress the internal insulation systems are the result of the windings response to overvoltages at transformer terminals. This article presents an analysis of overvoltages that stress the transformer insulation systems, which occur while switching off transformers in systems with vacuum circuit breakers. The analysis was based on the results of laboratory measurements of switching overvoltages at transformer terminals and inside the winding, in a model medium-voltage electrical network with a vacuum circuit breaker.
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Belsky, R. A., V. Y. Frolov, R. I. Zhiligotov, and E. P. Safonov. "Peducing the frequency of switching overvoltage in generator networks." Power engineering: research, equipment, technology 26, no. 3 (2024): 96–107. http://dx.doi.org/10.30724/1998-9903-2024-26-3-96-107.
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THE PURPOSE of the study is to study the problem of switching overvoltages in 10 kV generator networks. Using the Matlab Simulink package, create a model of common auxiliaries of a 10/0.4 kV power station, calculate the overvoltage at different sections of the current, evaluate the effect of vacuum switches on each other, evaluate the effectiveness of nonlinear overstrain limiters, with parallel switching.THE SCIENTIFIC SIGNIFICANCE consists in obtaining a method for calculating transients with simultaneous switching of several switches. THE PRACTICAL SIGNIFICANCE lies in the possibility of using the resulting model for a more accurate selection of protective equipment.METHODS. To create a model of common auxiliaries of 10/0.4 kV and the calculations of transition processes, it used a Matlab Simulink package. RESULTS. The article discusses switching overvoltages in their own needs of 10/0.4 kV. The influence of parallel switching of vacuum circuit breakers on the increase in the multiplicity of overvoltages is estimated. The influence of the specific energy intensity of nonlinear surge limiters on the multiplicity of overvoltages was also evaluated.CONCLUSION. This model showed that the parallel switching of two vacuum circuit breakers can increase the frequency of overvoltage by 20-40 %, which can lead to an increase in wear of both insulation of the protected equipment and the probability of re-breakdown in a vacuum chamber. Moreover, the higher the current cut, the higher the increase in the frequency of the overstrain, the multiplicity will also increase if the shutdown time between the switches is reduced. The main means of protection against switching overvoltages is a non -linear overstrain limiter, but when they are selected, the nominal working voltage is primarily taken into account, which leads to the fact that the increase in the frequency of overstrain from parallel switching can level the effectiveness of a nonlinear limiter.
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Lyakhomskii, A. V., S. V. Kuzmin, S. V. Petukhov, and A. P. Kudryashov. "Accident rate dynamics and enhanced phase-to-ground fault protection in 6-10 kv network and electrics in open pits and quarries." Mining informational and analytical bulletin, S64 (October 20, 2018): 134–44. http://dx.doi.org/10.25018/0236-1493-2018-12-64-134-144.
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At the current development stage of power supply in mines, the main causes of emergency power cutoffs are connected with phase-to-ground faults which are 3.9 times more often than short-circuits. This article analyzes origins of phase-to-ground faults and short-circuits in 6-10 kV networks in mines. The main causes are switching overvoltage, overvoltage under phase-to-ground faultо and natural ageing of insulation. It is shown that over a period of 2005 to 2015, once secondary switching overvoltages became one of the main causes of phase-toground faults. The authors emphasize the requirement of efficient limitation of switching overvoltages while reduction in grouped de-energization needs effective decrease in switching overvoltages under phase-to-ground faults and 100% selectivity of protections. Furthermore, phase-to-ground faults in 6-10 kV networks of quarries and open pit coal mines contributes to natural insulation aging governed by process and climatic factors. In terms of Chernogorsky open pit coal mine, the correlation dependence is obtained between total number of emergency power cutoffs and operation life. It is highlighted that the period of 2016 to 2018 shows a trend of reduction in phase-to-ground faults and short-circuits by 9 and 13%, respectively.
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Leman, Jon T., and Robert G. Olsen. "Bulk FDTD Simulation of Distributed Corona Effects and Overvoltage Profiles for HSIL Transmission Line Design." Energies 13, no. 10 (2020): 2474. http://dx.doi.org/10.3390/en13102474.
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Power system load growth and transmission corridor constraints are driving industry activity in the area of high surge impedance loading (HSIL). Examples include compact structure design and uprating existing transmission lines. Recent research relating electric field uniformity to transmission line capacity and critical flashover voltage underscored the need for better overvoltage data to quantify insulation margins for HSIL design. To that end, this work extends the finite difference time domain (FDTD) method with distributed corona losses to transmission lines with bundled conductors. The model was adapted for practical use in high-volume statistical transient simulation and applied to an example 500 kV line. Transients included line energization and trapped charge reclosing. Overvoltage profiles and statistical distributions were generated from 9500 simulations obtained by random breaker close timing and variation in line length and altitude. Distributed corona losses reduced 98th percentile line-to-ground switching overvoltages by 4%–14% of nominal. The estimated line-to-ground switching surge flashover probability was 54%–80% lower with corona loss. Corona had less impact on line-to-line overvoltages, but the effects were still notable. Results highlight the importance of considering detailed overvoltage profiles and accounting for corona loss attenuation when seeking to carefully quantify insulation design margins.
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Bayu Lopari, Argia, Zulhajji Zulhajji, and Yunus Tjandi. "ANALYSIS OF TRANSIENT OVERVOLTAGES DUE TO LIGHTNING SURGES AT 150KV MAKALE TANA TORAJA SUBSTATION." Jurnal Media Elektrik 22, no. 2 (2025): 167–77. https://doi.org/10.59562/metrik.v22i2.4508.
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Transient overvoltage is a phenomenon in the power system that can be caused by lightning or switching surges. These overvoltages have large amplitudes and short durations, potentially damaging equipment, especially the Circuit Breaker, leading to failure in power distribution. As such, analyzing transient overvoltage is critical for understanding its impact and for designing systems that can withstand such surges. This study investigates transient overvoltages at PT PLN (Persero) 150 kV Makale Tana Toraja Substation, calculating the highest possible transient overvoltage that could affect Circuit Breakers. The research employs a quantitative descriptive approach with an Ex-Post Facto design, using the lattice diagram method to analyze the transient overvoltage behavior. Findings reveal that the highest recorded transient overvoltage was 227.231 kV, with values decreasing as the distance from the lightning strike increases. Furthermore, calculations suggest that in the case of properly functioning arresters, transient overvoltage values at Circuit Breakers 1 and 2 are 512.33 kV and 542.514 kV, respectively. However, if the arresters are damaged, these values increase significantly to 1031.94 kV and 1028.814 kV. This study emphasizes the importance of maintaining functional lightning arresters to ensure protection system efficacy. By optimizing the design and operational parameters of protection equipment, this research contributes to strengthening the resilience of substations, ensuring the safety and reliability of critical infrastructure in areas prone to lightning strikes.
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Lobodzinskiy, Vadim, Nikolay Buryk, Lyudmila Spinul, Valeriy Chibelis, and Olga Illina. "Reduction of Overvoltages under Connection on a High-Voltage Cable Line Due to Optimal Controlled Switching." Problems of the Regional Energetics, no. 3(59) (August 2023): 25–32. http://dx.doi.org/10.52254/1857-0070.2023.3-59.03.
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The purpose of the work is to develop a mathematical model of a cable transmission line, which allows modeling and choosing the optimal conditions for controlled switching to limit overvoltage at the development and design stage. The goal is achieved by solving the problem of determining the initial angle of each phase, so that each phase has an initial switching angle equal to zero with a time delay. A high-voltage cable line for a voltage of 330 kV, implemented using Matlab, has been chosen as the object of study. The most significant result is the method of numerical simulation of the cable line that allows you to analyze transients when each phase of a three-phase cable line is connected to a three-phase source with a time delay, the switching angle of all phases is zero. This, in turn, makes it possible to limit switching overvoltages. The significance of the results obtained lies in the possibility of the proposed technique to choose the optimal conditions for controlled switching, which makes it possible to use it in the design of switching nodes, as well as the use of controlled switching to eliminate unwanted electrical transients during planned switching. The simulation results showed that the greatest effect of using numerical simulation is when each phase of a three-phase cable line is connected to a three-phase source with a time delay of 1/150 second, then the switching angle of all phases is zero, which makes it possible to limit switching overvoltages. Keywords: three-phase cable line, switching overvoltage, transient processes, controlled switching, theory of multipoles, modeling of electrical engineering objects.
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Jasika, Ranko, Jovan Mrvić, and Stefan Obradović. "Insulation stresses of power equipment exposed to non-standard overvoltage waveforms." Zbornik radova Elektrotehnicki institut Nikola Tesla, no. 32 (2022): 27–41. http://dx.doi.org/10.5937/zeint32-41430.
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During its operation, electrical equipment is constantly exposed to overvoltages of various waveforms, such as lightning discharges, switching operations, faults, etc. Therefore, adequate selection of overvoltage protection and equipment insulation withstand voltages are key factors in increasing system reliability. In general, insulation coordination is carried out by analyzing the insulation behavior for standard impulse and switching overvoltage waveforms. However, overvoltages that occur in operating conditions can significantly deviate from the standard waveforms of insulation withstand voltages, in terms of the front time, the duration of the wave, the existence of highfrequency components as result of reflections in the facility and other factors. This paper presents possible methods of assessing the behavior of equipment insulation for real voltage waves to which the insulation is exposed during exploitation and which deviate from standard waveforms, by analysis in the frequency domain. As there are different components in the overvoltage signal at different frequencies, which a different energy, the main goal of this paper is to analyze the insulation characteristics of a specific transformer from the point of view of the energy spectral density of the voltage wave that occurs at its terminals when an atmospheric discharge occurs. The analysis is based on the determination of the safety margin on the entire frequency spectrum of the overvoltage wave, that is, on the calculation of the so-called FDSF (Frequency Domain Severity Factor). The calculation results show that although the overvoltage amplitude is lower than the withstand voltage of the transformer insulation with an appropriate safety margin (the condition of the classic approach to insulation coordination is satisfied), the spectrum analysis of the voltage wave in the frequency domain shows that the insulation may still be compromised.
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Jasika, Ranko, Jovan Mrvić, and Stefan Obradović. "Insulation Stresses of Power Equipment Exposed to Non-standard Overvoltage Waveforms." Zbornik radova, Elektrotehnički institut Nikola Tesla 32, no. 32 (2022): 27–41. https://doi.org/10.5937/zeint32-41430.
Full textAbstract:
During its operation, electrical equipment is constantly exposed to overvoltages of various waveforms, such as lightning discharges, switching operations, faults, etc. Therefore, adequate selection of overvoltage protection and equipment insulation withstand voltages are key factors in increasing system reliability. In general, insulation coordination is carried out by analyzing the insulation behavior for standard impulse and switching overvoltage waveforms. However, overvoltages that occur in operating conditions can significantly deviate from the standard waveforms of insulation withstand voltages, in terms of the front time, the duration of the wave, the existence of high-frequency components as result of reflections in the facility and other factors. This paper presents possible methods of assessing the behavior of equipment insulation for real voltage waves to which the insulation is exposed during exploitation and which deviate from standard waveforms, by analysis in the frequency domain. As there are different components in the overvoltage signal at different frequencies, which a different energy, the main goal of this paper is to analyze the insulation characteristics of a specific transformer from the point of view of the energy spectral density of the voltage wave that occurs at its terminals when an atmospheric discharge occurs. The analysis is based on the determination of the safety margin on the entire frequency spectrum of the overvoltage wave, that is, on the calculation of the so-called FDSF (Frequency Domain Severity Factor). The calculation results show that although the overvoltage amplitude is lower than the withstand voltage of the transformer insulation with an appropriate safety margin (the condition of the classic approach to insulation coordination is satisfied), the spectrum analysis of the voltage wave in the frequency domain shows that the insulation may still be compromised
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Yu, Jian, Renhui Shen, Le Zhou, Zelin Jia, and Yulong Hao. "Investigation of a Low-Speed Commutation Voltage Shock Problem in Three-Level ANPC Inverter with Hybrid Modulation Mode." Machines 12, no. 1 (2023): 27. http://dx.doi.org/10.3390/machines12010027.
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With the development of the photovoltaic industry; there will be an increasing demand for efficient, high-power density, and low-cost grid interface converters. Compared with two-level inverters, multilevel inverters have the following advantages: (1) lower device voltage ratings; (2) better output filtering spectrum; (3) lower electromagnetic interference (EMI) noise; and (4) higher switching speed capability. However, the complex switching circuit of the multilevel inverter will bring more parasitic inductance, resulting in severe switching overvoltage (ringing). Especially in order to reduce the cost of the inverter, using the long-loop modulation mode, the commutation loop will introduce more parasitic inductance, which will make the overvoltage more serious. Consider that commonly used overvoltage absorption schemes are effective only for overvoltage or suppression of oscillations. Therefore, a new overvoltage absorption circuit is proposed in this paper, which can not only alleviate the overvoltage and ringing phenomena but also suppress the effect of voltage jumps during low-frequency switching on high-frequency input voltage. This overvoltage absorption circuit is characterized by low overvoltage, fast ringing damping, and minimum capacitance. Experiments and simulations are conducted to verify the effectiveness of this overvoltage absorption circuit using a three-level ANPC inverter as a prototype. The results show that the proposed overvoltage absorption circuit can significantly reduce the overvoltage level, shorten the oscillation time, and reduce the voltage difference between the upper and lower DC bus capacitors.
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Elshekhi, Abubkr Ali, Ali Tamtum, and Shukri El Dabar. "Switching overvoltage calculations and reduction, for 400 KV-line connecting Khoms and Gmmra substations." مجلة الجامعة الأسمرية: العلوم التطبيقية 1, no. 2 (2016): 141–49. http://dx.doi.org/10.59743/aujas.v1i2.1556.
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Transient overvoltage in power systems is one of the most important issues to be considered for system stability. Switching surges is one of the most important reasons that cause Transient overvoltage. This paper presents a full study of the high-voltage line connecting KHOMS and GMMRA substations. The study utilizes the Alternative Transient Program (ATP) to compute the transient overvoltage due to switching surges (line closing and re-closing); as well as presenting the usage of surge arrester with pre-insertion resistor to reduce the upper limit of transient overvoltage. The results present the positive effect of using surge arrester and resistor switching element to limit transient overvoltage and keep it at certain level; as well as damping the isolation in the voltage waveform.
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Tikhonov, K. V. "Study of switching overvoltages in electrical networks up to 1000 V." iPolytech Journal 27, no. 2 (2023): 370–79. http://dx.doi.org/10.21285/1814-3520-2023-2-370-379.
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The aim was to study the effect of switching modes on the power of supply transformers in electrical networks up to 1000 V on the multiplicity of switching overvoltages, as well as to develop recommendations for their reduction. The study was carried out during switching of supply transformers in networks up to 1000 V. Vacuum contactors were used to study overvoltages arising during switching of supply transformers. Overvoltages were recorded using an RDN-1000 active divider and a Tektronix TDS2024B digital oscilloscope. The RC circuit capacitance was measured by a Mastech MY6243 digital LC-meter. To limit switching overvoltages, RC quenchers based on RC circuits were used, reducing not only the switching pulse amplitude, but also the rate of the switching pulse voltage rise. In addition, RC quenchers lack fading zones under high-frequency switching pulses. The capacitance of the primary winding of the transformers under study was measured. An increase in the transformer power was found to lead to a decrease in the multiplicity of switching overvoltages, when the transformer is disconnected from the mains. Under a 1.5-fold increase in the power of the transformer, its inductance and wave impedance decreases. As a result, when the same capacitance is connected to the transformer terminals, the wave resistance in more powerful transformers will be reduced to a larger extent (by 3 to 6 times), thus providing a more effective overvoltage limitation. The conducted experimental studies confirmed the effectiveness of RC circuits in limiting switching overvoltages.
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Sadeghkhani, Iman, Abbas Ketabi, and Rene Feuillet. "Radial Basis Function Neural Network Application to Measurement and Control of Shunt Reactor Overvoltages Based on Analytical Rules." Mathematical Problems in Engineering 2012 (2012): 1–14. http://dx.doi.org/10.1155/2012/647305.
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This paper presents an artificial intelligence application to measure switching overvoltages caused by shunt reactor energization by applying analytical rules. In a small power system that appears in an early stage of a black start of a power system, an overvoltage could be caused by core saturation on the energization of a reactor with residual flux. A radial basis function (RBF) neural network has been used to estimate the overvoltages due to reactor energization. Equivalent circuit parameters of network have been used as artificial neural network (ANN) inputs; thus, RBF neural network is applicable to every studied system. The developed ANN is trained with the worst case of the switching angle and remanent flux and tested for typical cases. The simulated results for a partial of 39-bus New England test system show that the proposed technique can measure the peak values and duration of switching overvoltages with good accuracy.
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Borecki, Michał, and Maciej Ciuba. "Testing of Selected Surge Protection Devices in the Context of the Possibility of Ensuring the Reliability of Power Grids." Energies 16, no. 3 (2023): 1445. http://dx.doi.org/10.3390/en16031445.
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The paper aims to analyze the parameters of prototypes of new overvoltage protection devices for power grids—a multi-chamber insulator arrester (MCA) and a long flashover arrester (LFA). The article presents the research results on determining the actual MCA and LFA impact characteristics. Moreover, the results were compared to assess the effectiveness of the overvoltage protection devices. The research results presented in this article will supplement missing information about the devices. They will make it possible to evaluate the possibility of using overvoltage protection devices for a new type of spark gap based on a multi-segment system in high-voltage networks of a specific country. The analysis of its properties against the background of atmospheric overvoltages and their impact on high voltage lines will be carried out by assessing the effectiveness of the tested overvoltage protection device in laboratory conditions. The tests will also be carried out by applying standardized lightning and switching surges to the tested device to map the overvoltage processes on the power grid elements. Two different generators will be used for this purpose. The proposed research will also allow learning about the influence of structural elements on the operation of the tested devices.
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Г. О., ШЕЇНА. "Investigation of overvoltage in electrical networks." Journal of Electrical and power engineering 24, no. 1 (2021): 46–50. http://dx.doi.org/10.31474/2074-2630-2021-1-46-50.
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The paper considers the processes that occur in power lines and power transformers at atmospheric and switching overvoltages. Atmospheric overvoltages are divided into two types: direct, which occur due to a direct lightning strike; and induction - occur at any switching. Direct overvoltages reach values sufficient to cover the insulation of any voltage class. Protection of power transmission lines from them - suspension of grounded lightning protection cables, protection of substation equipment - installation of lightning rods. It is important to study the wave processes in power lines that occur when switching, which occurs when the power supply is turned on, when disconnected from the power supply, in the event of short circuits, when power lines are struck by lightning. In addition, it is important to study the wave processes in power transformers, the effect of the pulse corona, the effect of overvoltage on the transformer windings. In a more detailed analysis of the processes, the following conclusions were made: 1) under the condition of the same mains voltage, the voltage wave will be higher in the cable transmission line than in the air, due to the difference in impedance. 2) in the XX mode, the load current will drop to zero, and the load voltage will double. The voltage of the reflected wave will keep the sign. In short-circuit mode, the load voltage will drop to zero and the load current will double. The voltage of the reflected wave will change the sign. Thus, when the substation equipment is under a voltage close to XX, there is a probability of equipment damage during atmospheric overvoltages. 3) For substations that are powered by overhead power lines, it is advisable to use a tank to smooth the slope of the refracted wave, and for substations that are powered by cable transmission lines, it is advisable to use inductance to smooth the slope of the refracted wave. 4) Inductance and capacitance can have a significant effect on the amplitude of the voltage wave, provided that. 5) Capacitance performs protective functions in all directions, both refracted and reflected wave, and inductance only smooths the refracted wave. The obtained relations can be used to study the overvoltage in the connection nodes of node substations.
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Zhou, Zikai, Yaxun Guo, Xiaofeng Jiang, et al. "Study on Transient Overvoltage of Offshore Wind Farm Considering Different Electrical Characteristics of Vacuum Circuit Breaker." Journal of Marine Science and Engineering 7, no. 11 (2019): 415. http://dx.doi.org/10.3390/jmse7110415.
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For the study of transient overvoltage (TOV) in an offshore wind farm (OWF) collector system caused by switching off vacuum circuit breakers (VCBs), a simplified experimental platform of OWF medium-voltage (MV) cable collector system was established in this paper to conduct switching operation tests of VCB and obtain the characteristic parameters for VCB, especially dielectric strength parameters; also, the effectiveness of the VCB reignition model was verified. Then, PSCAD/EMTDC was used to construct the MV collector system of the OWF, and the effects of normal switching and fault switching on TOV amplitude, steepness, and the total number of reignition of the VCB were studied, respectively, with the experimental parameters and traditional parameters of dielectric strength of the VCB. The simulation results show that when the VCB is at the tower bottom, the overvoltage amplitude generated by the normal switching is the largest, which is 1.83 p.u., and the overvoltage steepness of the fault switching is the largest, up to 142 kV/μs. The overvoltage amplitude and steepness caused by switching off VCB at the tower bottom faultily with traditional parameters are about 2 and 1.5 times of the experimental parameters under the same operating condition.
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Shevtsov, Dmitry, Dmitry Pavluchenko, and Evgeny Prohorenko. "The Basic Principles of Controlled Switching and Synchronous Vacuum Circuit Breaker Application in Local Distribution Networks." Applied Mechanics and Materials 698 (December 2014): 743–48. http://dx.doi.org/10.4028/www.scientific.net/amm.698.743.
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The paper is devoted to the solution of the switching overvoltage problem in distribution networks by application synchronous vacuum circuit breaker. The basic principles of controlled switching are considered. The example of vacuum circuit breaker application realizing principles of synchronous switching is presented. It is shown, that synchronous vacuum circuit breaker is reliable and effective device for overvoltage reduction.
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Adalev, A. S., V. V. Glushakov, R. A. Karzunov, M. V. Pronin, and N. I. Fedorov. "Calculation of RC Circuits, Switching Overvoltage and Energy Loss in Thyristor Converters." LETI Transactions on Electrical Engineering & Computer Science 15, no. 7 (2022): 57–65. http://dx.doi.org/10.32603/2071-8985-2022-15-7-57-65.
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In thyristor converters, abrupt voltage changes occur during switching of valves. The voltages change most significantly when the thyristors are switched off. To limit overvoltage, thyristors are shunted by RC circuits. RC circuits reduce overvoltages, but usually do not eliminate them completely. Switching overvoltages depend on the reverse current in thyristors when they are switched off, on the parameters of the converter circuit and on the parameters of RC circuits. Experimental studies have been carried out and a simulation model with a thyristor rectifier and RC circuits in MatLab-Simulink has been developed taking into account special resonant circuits forming a proper current shape. Calculations of electric processes in the model have been performed. The results of the calculations were compared with experimental data, and a sufficient coincidence was achieved.
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Eliyan, Tamer, Saad F. Al-Gahtani, Z. M. S. Elbarbary, and Fady Wadie. "Characterization of lightning-induced overvoltages in wind farms." PLOS One 20, no. 6 (2025): e0325514. https://doi.org/10.1371/journal.pone.0325514.
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Wind farms are exposed to various weather hazards, including lightning strikes, which can pose significant risks. However, the impact of different wind farm topologies on the magnitude of lightning-induced overvoltages has not been extensively studied, creating a gap in existing literature. This paper addresses this gap by analyzing the characteristics of lightning-induced overvoltages injected into the grid for various wind farm topologies. The scientific scope of this study is to evaluate the influence of wind farm topology on the severity of different types of lightning-induced overvoltages including positive, negative, and double-peaked lightning strikes, using simulation-based analysis. The topologies tested include radial, single-sided ring (SSR), double-sided ring (DSR), and star topologies. The results demonstrate that radial topology leads to the highest overvoltage injection, while switching to SSR, DSR, or star topologies results in reductions of overvoltage by 11.5% to 51.0%, 39.5% to 66.0%, and 62.3% to 89.0%, respectively. These results support a topology-based risk assessment approach, offering clear guidance for selecting configurations that improve lightning resilience.
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Mazyed, A. Al-Tak, Fadzil bin Ain Mohd, Sh.Al-Yozbaky Omar, and Kamarol Mohd Jamil Mohamad. "A novel method of overvoltage suppression due to de-energization of shunt reactor in high voltage system." A novel method of overvoltage suppression due to de-energization of shunt reactor in high voltage system 14, no. 4 (2023): 2134–47. https://doi.org/10.11591/ijpeds.v14.i4.pp2134-2147.
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Substations usually employ shunt reactors to reduce the reactive power of systems. Due to current chopping when the shunt reactor is shut off, a high frequency and amplitude overvoltage is generated. This study was aimed at eliminating switching-related overvoltages in shunt reactors so as to maintain the equipment, prevent insulation failure, and avoid reignition. Therefore, the circuit was modified according to the suggested mitigation strategy to verify that transient overvoltages are suppressed by the circuit breaker and shunt reactor. With a view to evaluate the existing chopping caused by the switching of reactor bank, the alternative transients program (ATP-Draw) model was used to simulate the transients resulting from switching a shunt reactor. This work has been put into practice for various current chopping values. The collected results of the simulation showed that the proposed model was significantly highlighted for the suppression of overvoltages, with the voltage across the circuit breaker being reduced from 679 KV to 478 KV at a current chopping value of 5 A and from 351 KV to 152 KV across the shunt reactor.
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Chen, Jiangui, Yan Li, and Mei Liang. "A Gate Driver Based on Variable Voltage and Resistance for Suppressing Overcurrent and Overvoltage of SiC MOSFETs." Energies 12, no. 9 (2019): 1640. http://dx.doi.org/10.3390/en12091640.
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A SiC MOSFET is a suitable replacement for a Si MOSFET due to its lower on-state resistance, faster switching speed, and higher breakdown voltage. However, due to the parasitic parameters and the low damping in the circuit, the turn-on overcurrent and turn-off overvoltage of a SiC MOSFET become more severe as the switching speed increases. These effects limit higher frequency applications of SiC MOSFET. Based on the causes of overcurrent and overvoltage of SiC MOSFET, a novel gate driver with the variable driving voltage and variable gate resistance is proposed in this paper to suppress the overcurrent and overvoltage of SiC MOSFETs. The proposed gate driver can realize the variation in driving voltage and gate resistance during switching transitions. It not only suppresses the overcurrent and overvoltage of SiC MOSFETs, but also has little effect on switching loss. The working principle of the proposed gate driver is analyzed in this paper. Finally, experimental verification on a double-pulse test platform is performed to verify the effectiveness of the proposed gate driver.
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Al-Tak, Mazyed A., Mohd Fadzil Bin Ain, Omar Sh Al-Yozbaky, and Mohamad Kamarol Mohd Jamil. "A novel method of overvoltage suppression due to de-energization of shunt reactor in high voltage system." International Journal of Power Electronics and Drive Systems (IJPEDS) 14, no. 4 (2023): 2134. http://dx.doi.org/10.11591/ijpeds.v14.i4.pp2134-2147.
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<span lang="EN-US">Substations usually employ shunt reactors to reduce the reactive power of systems. Due to current chopping when the shunt reactor is shut off, a high frequency and amplitude overvoltage is generated. This study was aimed at eliminating switching-related overvoltages in shunt reactors so as to maintain the equipment, prevent insulation failure, and avoid reignition. Therefore, the circuit was modified according to the suggested mitigation strategy to verify that transient overvoltages are suppressed by the circuit breaker and shunt reactor. With a view to evaluate the existing chopping caused by the switching of reactor bank, the alternative transients program (ATP-Draw) model was used to simulate the transients resulting from switching a shunt reactor. This work has been put into practice for various current chopping values. The collected results of the simulation showed that the proposed model was significantly highlighted for the suppression of overvoltages, with the voltage across the circuit breaker being reduced from 679 KV to 478 KV at a current chopping value of 5 A and from 351 KV to 152 KV across the shunt reactor.</span>
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Martinez, Juan A., Dan Goldsworthy, and Randy Horton. "Switching Overvoltage Measurements and Simulations—Part I: Field Test Overvoltage Measurements." IEEE Transactions on Power Delivery 29, no. 6 (2014): 2502–9. http://dx.doi.org/10.1109/tpwrd.2014.2303575.
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Li, Bing, Haoran Chen, Chuanqi Zhou, Xingyu Li, Jundi Liu, and Hanxu Wu. "Real-type test platform capacitor bank switching oscillation suppression strategy and switching device design." Journal of Physics: Conference Series 2849, no. 1 (2024): 012008. http://dx.doi.org/10.1088/1742-6596/2849/1/012008.
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Abstract The true-type test platform is widely used to evaluate whether relay protection devices are effective and accurate in handling simulated single-phase ground faults. However, since the system scale needs to be increased or decreased by switching capacitors connected in parallel on the feeder line, uncontrolled switching of capacitors may cause the magnetic latching relay to burn out. This article studies the transient process of switching and analyzes the reasons for relay burnout. Switching capacitors at non-current zero-crossing points will produce a large inrush overvoltage, which will burn the relay. To solve this problem, a switching control strategy based on delay compensation is proposed to ensure no inrush overvoltage during the switching process, improve the service life of the magnetic latching relay, and improve the safety of the power capacitor.
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Manihuruk, Jonner, Toga Simorangkir, and Novrin L. Sitanggang. "Studi Kemampuan Arrester Untuk Pengaman Transformator Pada Gardu Induk Tanjung Morawa 150 KV." Jurnal ELPOTECS 4, no. 1 (2021): 16–25. http://dx.doi.org/10.51622/elpotecs.v4i1.447.
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Overvoltage is a voltage that can only be held for a very limited time. Overvoltage that occurs for a time that exceeds the equipment's capacity limit will damage the equipment connected to the network that is subjected to overvoltage. Lightning overvoltage is a periodic overvoltage caused by external overvoltage, both direct and indirect strikes. Lightning overvoltage only lasts a very short time but has a voltage that is so high that it exceeds the operating voltage of the equipment so it is potentially very damaging. Lightning Arrester is an installation safety equipment from overvoltage disturbances due to lightning strikes (Lightning Surge) or by switching surges (Switching Surge). Transformer / power transformer serves to distribute power / electrical power by increasing or decreasing the voltage at the substation. This research focuses on substation equipment, namely Lightning Arrester ASEA type XAR 170A3/144 which is connected to a Power I transformer (transformer) UNINDO 906007289. Good protection is obtained when the arrester is placed as close as possible to the transformer clamp. However, in practice the arrester must be located at a distance X from the transformer being protected. Therefore, the distance must be determined properly so that the resulting protection can be obtained properly. Arrester installation according to theory is 50 meters from the transformer, in practice at the TAMORA Substation the arrester distance is 3 meters from the temporary transformer based on calculations in this final project the best distance is 10.96 meters.
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Siagian, Lestina, Widia Viviana Simanjuntak, and Junus Sunaryo Banjarnahor. "Desain Pemrograman Visual Pengendalian Nomor Urut." Jurnal ELPOTECS 4, no. 1 (2021): 26–31. http://dx.doi.org/10.51622/elpotecs.v4i1.448.
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Overvoltage is a voltage that can only be held for a very limited time. Overvoltage that occurs for a time that exceeds the equipment's capacity limit will damage the equipment connected to the network that is subjected to overvoltage. Lightning overvoltage is a periodic overvoltage caused by external overvoltage, both direct and indirect strikes. Lightning overvoltage only lasts a very short time but has a voltage that is so high that it exceeds the operating voltage of the equipment so it is potentially very damaging. Lightning Arrester is an installation safety equipment from overvoltage disturbances due to lightning strikes (Lightning Surge) or by switching surges (Switching Surge). Transformer / power transformer serves to distribute power / electrical power by increasing or decreasing the voltage at the substation. This research focuses on substation equipment, namely Lightning Arrester ASEA type XAR 170A3/144 which is connected to a Power I transformer (transformer) UNINDO 906007289. Good protection is obtained when the arrester is placed as close as possible to the transformer clamp. However, in practice the arrester must be located at a distance X from the transformer being protected. Therefore, the distance must be determined properly so that the resulting protection can be obtained properly. Arrester installation according to theory is 50 meters from the transformer, in practice at the TAMORA Substation the arrester distance is 3 meters from the temporary transformer based on calculations in this final project the best distance is 10.96 meters.
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Wang, Kefeng, Fuyue Wen, Baokui Sun, Jianbo Zhou, Lei Han, and Jiangyong Wang. "Gate modulation drive and modeling of IGBT in MMC converters." Journal of Physics: Conference Series 2474, no. 1 (2023): 012031. http://dx.doi.org/10.1088/1742-6596/2474/1/012031.
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Abstract The energy surplus caused by the alternating current (AC) system’s failure results in a severe overvoltage problem in Bai hetan-Jiangsu ±800 kV hybrid cascade direct current (DC) project. However, the insulated gate bipolar transistor’s (IGBT) off-state voltage is the crucial reason for the insufficient voltage capacity of modular multilevel converter (MMC). Therefore, analysis and suppression of the off-state overvoltage are of vital significance. The off-state model of IGBT in an MMC converter is established, and the process of IGBT’s turning off is analyzed. Then, based on the characteristics of IGBT’s off-state and traditional resistance switching strategy, the gate modulation drive strategy is proposed, and the equivalent topology of the MMC submodule with the strategy is established. Finally, MMC submodule models with gate modulation drive and resistance switching strategy, respectively, are built in simulation software, and two groups of data are compared under multiple groups of the control cycle and reference current slope given. The simulation results show that the gate modulation drive supresses the off-state overvoltage on IGBT better than the resistance switching strategy. Moreover, the shorter the control cycle and the less reference current slope, the better the overvoltage suppression.
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Zhang, Kun, Jianqiao Hu, Xiaoyan Lu, Zhengwei Peng, Peihua Ma, and Feng Gao. "Influence of fast switching fault current limiter on electromagnetic transient of extra-high voltage transmission line." Journal of Physics: Conference Series 2903, no. 1 (2024): 012007. https://doi.org/10.1088/1742-6596/2903/1/012007.
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Abstract The rapid advancement of power systems has led to an increase in short-circuit currents. The short-circuit current can be effectively limited by adding a fast-switching fault current limiter. However, incorporating a current-limiting reactor into ultra-high voltage lines may impact electromagnetic transients. This study utilizes PSCAD/EMTDC electromagnetic transient simulation software to develop a typical 330kV transmission line model for simulation analysis. The paper aims to study whether the current limiting reactor will affect the switching overvoltage in the automatic reclosing overvoltage. The results show that the input of the current-restricting transformer efficiently constrains the magnitude of short-circuit currents and exerts minimal influence on the automatic reclosing overvoltage in ultra-high voltage transmission lines.
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SADEGHKHANI, IMAN, ABBAS KETABI, and RENE FEUILLET. "CONTROL OF SHUNT REACTOR OVERVOLTAGES BY CONTROLLED SWITCHING DURING POWER SYSTEM RESTORATION." Journal of Circuits, Systems and Computers 21, no. 07 (2012): 1250051. http://dx.doi.org/10.1142/s021812661250051x.
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The shunt reactors located on both line terminals and substation bus-bars are commonly used on long extra high voltage (EHV) transmission systems for controlling voltage during load variations. In a small power system that appears in an early stage of a black start of a power system, an overvoltage could be caused by core saturation on the energization of a shunt reactor with residual flux. The most effective method for the limitation of the switching overvoltages is controlled switching since the magnitudes of the produced transients are strongly dependent on the closing instants of the switch. A harmonic index has been introduced that it's minimum value is corresponding to the best-case switching time. In addition, in this paper an artificial neural network (ANN) is used to estimate the optimum switching instants for real time applications. ANN is trained with equivalent circuit parameters of the network, so that developed ANN is applicable to every studied system. To verify the effectiveness of the proposed index and accuracy of the ANN-based approach, two case studies are presented and demonstrated.
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Prabowo, Rizky Drajat, and Badaruddin Badaruddin. "ANALISA INRUSH CURRENT DAN TRANSIENT OVERVOLTAGE TRANSFORMATOR 292 MVA DENGAN PENGUJIAN LINE CHARGING STUDI KASUS PADA PLTGU CILEGON." Transmisi 24, no. 1 (2022): 29–37. http://dx.doi.org/10.14710/transmisi.24.1.29-37.
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Kehandalan sistem dan peralatan yang memberikan supply listrik kepada konsumen menjadi fokus utama dalam upaya penyediaan energi listrik. Untuk memastikan kehandalan tersebut dilakukan serangkaian pengujian dalam sistem kelistrikan, salah satu pengujian tersebut adalah pengujian line charging. Pengujian line charging adalah kondisi dimana mesin pembangkit beroperasi isolated untuk memberikan supply ke saluran transmisi, peralatan transmisi dan ke beban, dalam situasi yang dikondisikan. Peralatan penting yang memiliki kemungkinan failure dalam pengujian tersebut adalah transformator. Dampak operasi transformator dalam pengujian line charging adalah terjadinya inrush current dan transient overvoltage. Hal tersebut memiliki potensi mengurangi kehandalan transformator. Penelitian ini dilakukan untuk mengetahui nilai inrush current, transient overvoltage dan mengetahui dampaknya terhadap transformator dari data hasil simulasi pemodelan dan data aktual pengujian line charging. Berdasarkan hasil analisa yang dilakukan inrush current dan transient overvoltage terbesar diperoleh dari pemodelan dengan metode switching pada 52L dengan nilai 6.56 kA dan 307.3 kV. Nilai transient overvoltage dari hasil simulasi menunjukkan hasil 2.5 kali dari tegangan nominalnya, hal ini jika dilakukan terus menerus akan menyebabkan kegagalan operasi transformator. Metode yang paling efektif untuk menurunkan inrush current adalah metode switching pda 52G dengan sequential switch, dengan metode ini didapatkan penurunan inrush current sebesar 83.6 % dari metode 52G.
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Guo, Hongbing, Jianying Meng, Yue Yang, Lu Zheng, Xuan Liu, and Ming Tan. "Life Prediction of Dry Reactor Sensor Based on Deep Neural Network." Journal of Sensors 2022 (June 25, 2022): 1–7. http://dx.doi.org/10.1155/2022/6982950.
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In order to solve the problem of increasing the number and service life of a dry-type air core reactor and frequent interturn insulation faults, this paper proposes a life prediction method of a dry-type reactor sensor based on the deep neural network. On the basis of summarizing the research status of turn-to-turn insulation-related problems, this method studies the switching overvoltage generated in the process of breaking the dry-type air core reactor, the deterioration law of turn-to-turn insulation under the cumulative action of switching overvoltage, the influence of thermal aging on the Switching Overvoltage Withstand characteristics of turn-to-turn insulation, and the electrical aging life of turn-to-turn insulation under the power frequency overvoltage. Based on the deep neural network, the electrical aging life model of turn-to-turn insulation of the dry-type air core reactor under power frequency overvoltage is obtained. The results are as follows: with the increase of the applied voltage amplitude, the deterioration speed of the turn-to-turn insulation of the model sample accelerates. When the applied voltage amplitude reaches a certain value, the maximum discharge amount and pulse discharge power of the partial discharge pulse increase rapidly, and the image coincidence degree reaches 85%. The electric aging life curve of the modified interturn insulation model sample of the dry-type air core reactor has a high correlation with the measured aging life data, and the performance is more than 95%. The research results of this paper lay a practical foundation for further research on the deterioration mechanism of interturn insulation under the combined action of multiple factors and provide theoretical support for the risk and life assessment of the dry-type air core reactor.
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Soomro, Mansoor, Riaz Abbasi, Mazhar Baloch, Sohaib Tahir Chauhdary, and Mokhi Maan Siddiqui. "Assessment of Insulation Coordination and Overvoltage for Utility Girds Integrated with Solar Farms." Energies 17, no. 21 (2024): 5487. http://dx.doi.org/10.3390/en17215487.
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Due to the economic and environmental concerns associated with fossil fuels, many government and private organizations are progressively shifting towards the integration of solar farms with Utility Grids. However, these systems are facing insulation failure issues due to internal and external transient overvoltage’s, in which their shape, magnitude, and duration are unpredictable, and consequently, the insulation stress also becomes unpredictable. To ensure the safety and integrity of the system against any transient overvoltage event, it is important to carry out an insulation coordination analysis. The primary goal of this research work is to achieve this optimization in an economically viable manner, ensuring both operational stability and cost-effectiveness in the design of electrical equipment like surge Arresters. The research work presented in the literature does not fully evaluate all International Electrotechnical Commission (IEC) overvoltage classes as specified in the insulation coordination standards for Utility Grids integrated with solar farms. Therefore, this research paper investigates the impact of various transient and switching overvoltage conditions, as defined in the IEC 60071.4 Insulation Coordination Standard at the Solar and Utility Grid Electrical power system using PSCAD 4.6/EMTP Software. Five distinct simulation scenarios were developed to assess the systems’ resilience against insulation stress events. The proposed system was also examined with and without the application of a lightning surge arrester.
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Liu, Qiujiang, Binghan Sun, Qinyao Yang, Mingli Wu, and Tingting He. "Harmonic Overvoltage Analysis of Electric Railways in a Wide Frequency Range Based on Relative Frequency Relationships of the Vehicle–Grid Coupling System." Energies 13, no. 24 (2020): 6672. http://dx.doi.org/10.3390/en13246672.
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Harmonic overvoltage in electric railway traction networks can pose a serious threat to the safe and stable operation of the traction power supply system (TPSS). Existing studies aim at improving the control damping of grid-connected converters, neglecting the impedance frequency characteristics (IFCs) of the actual TPSS. The applicable frequency range of these studies is relatively low, usually no more than half of the switching frequency, and there is a large gap with the actual traction network harmonic overvoltage frequency range of 750 Hz–3750 Hz. In this paper, first, the IFCs of the actual TPSS in the wide frequency range of 150 Hz–5000 Hz are obtained through field tests, and the resonant frequency distribution characteristics of TPSS are analyzed. After that, the aliasing effect of the sampling process and the sideband effect of the modulation process of the digital control of the grid-connected converter are considered. Based on the relative relationships among the inherent resonant frequency of the TPSS, sampling frequency and switching frequency, an impedance matching analysis method is proposed for the wide frequency range of the vehicle–grid coupling system. By this method, the sampling frequency and switching frequency can be decoupled, and the harmonic overvoltage of traction network in the frequency range of two times switching frequency and above can be directly estimated. Finally, the method proposed in this paper is validated by the comparative simulation analysis of seven different cases.
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Wang, Zheng De. "Fault Analysis of Switching Regulator Induced by the Diode Turn-On Time." Advanced Materials Research 779-780 (September 2013): 1207–10. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.1207.
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Recently, switching regulator clock rate and transition time have become faster, making diode turn-on time a critical issue. A potential difficulty due to diode turn-on time is that the resultant transitory overshoot voltage across the diode, even when restricted to nanoseconds, can induce overvoltage stress, causing switching regulator IC failure. This paper provides a testing methology enabling proper diode selection for switching regulators.
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Síťař, Vladislav, and Jan Veleba. "Modelling of Metal Oxide Surge Arresters in Simulation Software DYNAST." TRANSACTIONS ON ELECTRICAL ENGINEERING 6, no. 1 (2020): 21–27. http://dx.doi.org/10.14311/tee.2017.1.021.
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This paper describes the possibilities for mathematical modelling of gap-less surge arresters in simulation software DYNAST. This tool does not belong to standard modelling softwares in the field of electric power engineering. However, it may provide some key advantages when compared to more frequently used softwares such as EMTP-ATP and MATLAB-Simulink. Description of the metal oxide varistor modelling at temporary and switching overvoltages, fast-front states, and lightning strokes is presented. More information about the defined internal structure of surge arrester models and ways for implementing respective V-I characteristics are provided. To verify the correct behaviour of the models, both slow and fast overvoltage scenarios are simulated and evaluated.
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CHMIELEWSKI, Tomasz. "Switching overvoltage analyses under distorted supply voltage conditions." PRZEGLĄD ELEKTROTECHNICZNY 1, no. 3 (2019): 121–27. http://dx.doi.org/10.15199/48.2019.03.28.
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Marković, Nenad, Slobodan Bjelić, and Strahinja Marković. "The analytical method for determining the parameters of impulse overvoltages from atmospheric discharges." Bakar 50, no. 1 (2025): 89–104. https://doi.org/10.5937/bakar2501089m.
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Impulse generators with RC circuits form the foundation for producing surge voltages used in high-voltage equipment testing. In high-voltage engineering literature, the expressions for impulse voltage waveforms include known parameters of lightning or switching overvoltages, which are used to determine the amplitudes and time constants of impulse overvoltages in RC discharge circuits. However, both standards and scholarly publications often lack clarification for various ambiguities-such as the commonly cited factor of 1.67 for rise time-without providing rigorous physical or mathematical justification. All overvoltage parameters are typically defined axiomatically, and the existing formulas for designing impulse voltage generators are often inadequate. This paper presents implemented formulas and derived solutions that enable accurate determination of all parameters and electrical quantities of an RC circuit generating a specified impulse voltage waveform. For method verification, an adapted module of the MATLAB simulation package, psbsurgeovervoltage.mdl, was employed.
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Florkowski, Marek, Jakub Furgał, and Maciej Kuniewski. "Propagation of Overvoltages in the Form of Impulse, Chopped and Oscillating Waveforms in Transformer Windings—Time and Frequency Domain Approach." Energies 13, no. 2 (2020): 304. http://dx.doi.org/10.3390/en13020304.
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This paper describes a comparison of overvoltage propagation in transformer windings. Expanding and evolving electrical networks comprise various classes of transient waveforms, related to network reconfigurations, failure stages and switching phenomena, including new sources based on power electronics devices. In particular, the integration of renewable energy sources—mainly solar and wind—as well as expanding charging and energy storage infrastructure for electric cars in smart cities results in network flexibility manifested by switching phenomena and transients propagation, both impulse and oscillating. Those external transients, having a magnitude below the applied protection level may have still a considerable effect on winding electrical insulation in transformers, mainly due to internal resonance phenomena, which have been the root cause of many transformer failures. Such cases might occur if the frequency content of the incoming waveform matches the resonance zones of the winding frequency characteristic. Due to this coincidence, the measurements were performed both in time and frequency domain, applying various classes of transients, representing impulse, chopped (time to chopping from 1 µs to 50 µs) and oscillating overvoltages. An additional novelty was a superposition of a full lighting impulse with an oscillating component in the form of a modulated wavelet. The comparison of propagation of those waveforms along the winding length as well as a transfer case between high and low voltage windings were analyzed. The presented mapping of overvoltage prone zones along the winding length can contribute to transformer design optimization, development of novel diagnostic methodology, improved protection concepts and the proper design of modern networks.
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SHVETS, Nikolay N., Nikolay M. LEPEKHIN, Valery P. MIROSHNICHENKO, et al. "Electric Power Distribution System Overvoltage Protection Devices." Elektrichestvo, no. 2 (2022): 4–18. http://dx.doi.org/10.24160/0013-5380-2022-2-4-18.
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Surge protection devices of limiting and combined types used in 0.4 kV electric power distribution networks are described, and results of their experimental studies are presented. The devices have been developed in four earthquake-resistant designs with the use of new-generation nonlinear resistors (varistors) and controlled vacuum arresters. The developed protective devices are intended to limit transient overvoltages, which occur under the influence of man-made, natural and switching electromagnetic pulses, to a safe level, which for the developed design versions of protective devices lies in the range from 1.5 kV to 4.0 kV, and to remove pulses of high-energy currents (up to 500 kJ in a pulse). The article presents the results from studies of the switching characteristics of the developed protective devices in their nominal (multiple) and maximum (single) operation modes, with the measurement of limit voltages at their terminals. The practical effectiveness of using the combined type protective devices is estimated, and the performance characteristics of protection devices from different manufacturers are given.
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Panteleev, V. I., I. S. Kuzmin, A. A. Zavalov, A. V. Tikhonov, and E. V. Umetskaia. "Power quality in power supply systems of mining and processing enterprises in Russia." Proceedings of Irkutsk State Technical University 25, no. 3 (2021): 356–68. http://dx.doi.org/10.21285/1814-3520-2021-3-356-368.
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This paper investigates the effect of the load factor of frequency converters and thyristor converters on electrical power quality. Recommendations for reducing the influence of higher harmonics and switching overvoltages on the characteristics of electrical power are provided. Higher harmonics were measured by a PKK57 complex device for controlling electrical parameters and a digital oscilloscope of the Tektronix TDS 2024V type. Impulse switching overvoltages were recorded by an active resistance divider of the DNEK-10 type and the above-mentioned oscilloscope. The obtained data were processed by the Loginom 6.4 software and the methods of mathematical statistics. The lower threshold level of the load factor of frequency converters and thyristor converters was set equal to 0.8, at which the sinusoidal distortion of voltage curves correspond to the RF standard of electrical power quality. The suppression degree of higher harmonics from the 5th to 17th frequency by power transformers with a capacity of 250–6,300 kV. A ranged from 95 to 45%. The use of the ‘transformer–converter–electric receiver’ system as applied to the power supply systems of mining and processing enterprises was substantiated. It was shown that electric motors with a capacity of up to 2,500 kW inclusively require protection against switching overvoltages. Conventional RC-absorbers based on RC-circuits connected to the terminals of electric motors are shown to be highly efficient for protecting electric motors against switching overvoltages. Thus, the quality of electrical power in power supply systems of mining and processing enterprises in Russia can be ensured by frequency converters and thyristor converters with a load factor of 0.8 or greater. Provided that the transformer capacity does not exceed 1,000 kV. A, a more efficient and less expensive ‘transformer–converter–electrical receiver’ system is recommended. Effective protection of electric motors of up to 2,500 kW inclusive can be provided using the proposed conventional RC absorber, which maintains the overvoltage rate at a level not exceeding 1.7.
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Kazakova, S. A. "The Use of Line Surge Arresters to Provide Safety of Live Working." Applied Mechanics and Materials 698 (December 2014): 738–42. http://dx.doi.org/10.4028/www.scientific.net/amm.698.738.
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Live working (LW) is performed to provide high reliability of transmission lines (TL). Only “bare hand” method of LW is used at voltage systems more than 200 kV. Live working (LW) is possible if the minimum approaching distances are in working place. This requirement provides the safety of LW excluding flashover of insulating gaps under the switching overvoltage impact. In some cases it is impossible to provide the required gaps in LW zone. In order to protect it against possible flashover, special arresters were designed. Their effect on overvoltage magnitude was checked in calculations.
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Liu, Hong Shun, Ting Ting Lv, Ming Ming Han, Liang Zou, Li Zhang, and Qing Quan Li. "Close-Operation Overvoltage of No-Load Transmission Line with Fault Current Limiter." Applied Mechanics and Materials 672-674 (October 2014): 1373–79. http://dx.doi.org/10.4028/www.scientific.net/amm.672-674.1373.
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The comprehensive impacts of series resonance type fault current limiter (FCL) on power system need further investigation and verification. With regard to switching on 500kV EHV no-load transmission line, the instantaneous peak value, the free component oscillation frequency, the fundamental component amplitude and free component amplitude of terminal overvoltage waveform are simulated with and without installation of FCL considering different switching times. The relationship curves of free component oscillation period, the fundamental component amplitude and free component amplitude are gotten respectively by simulation results. The law of the influence of different fault current limiting reactance on terminal voltage of switching on no-load line is also summarized. The analysis results show that the installation of FCL is benefit for switching on no-load line.
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Sun, Jixing, Kaixuan Hu, Yongzhi Fan, Jiyong Liu, Shengchun Yan, and Yan Zhang. "Modeling and Experimental Analysis of Overvoltage and Inrush Current Characteristics of the Electric Rail Traction Power Supply System." Energies 15, no. 24 (2022): 9308. http://dx.doi.org/10.3390/en15249308.
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High-speed EMUs (electric multiple-units) frequently pass through the phase-separation zone during operation. Overvoltage generated during the operation of the vehicle-mounted circuit breaker has a long duration and high waveform steepness, which accelerates the service life of the vehicle-mounted equipment and is likely to cause insulation failures. For the above-mentioned problems, the operating overvoltage characteristics of high-speed EMU were obtained by traction substation-catenary-EMUs system (SCES) analysis and experiments, thus deriving the influences of the closed phase angle and the residual magnetism of the vehicle-mounted transformer on operating overvoltage. The results showed that the voltage phase of the catenary significantly affected the operating overvoltage, and the closed switching overvoltage was small at 0–40°, 140–210° and 320–350°. The voltage on the primary side of the vehicle-mounted transformer was 60.78 kV, with the transient impact of high-frequency oscillation overvoltage of 22.71 kV, and an initial period of oscillation of 0.01 ms. Then, the period became longer, and it took 0.5 ms for the high-frequency oscillation from attenuation to disappearance. Finally, a scheme of series reactance suppression devices was proposed to protect vehicle-mounted voltage transformers. This work is to provide data support for the insulation design and system protection of a traction power supply system.
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Ren, Hongtao. "Analysis on switching overvoltage of 500 kV GIS disconnector." Energy Reports 8 (August 2022): 169–76. http://dx.doi.org/10.1016/j.egyr.2022.02.143.
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Yang, Yalong, Ling Zhang, Ge Gao, Li Jiang, and Fengwei Zha. "Analysis of suppression switching overvoltage for CRAFT power supply." Energy Reports 8 (July 2022): 1656–66. http://dx.doi.org/10.1016/j.egyr.2022.02.288.
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Tao Zhang, Liuxue Sun, and Yin Zhang. "Study on Switching Overvoltage in Off-Shore Wind Farms." IEEE Transactions on Applied Superconductivity 24, no. 5 (2014): 1–5. http://dx.doi.org/10.1109/tasc.2014.2340438.
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Awad, Eman A., Ebrahim A. Badran, and Fathi M. H. Youssef. "A proposed supercapacitor-based mitigation of microgrid switching overvoltage." International Transactions on Electrical Energy Systems 28, no. 2 (2017): e2484. http://dx.doi.org/10.1002/etep.2484.
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