Journal articles: 'Transient overvoltage'

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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 (June 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 (May 22, 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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Furgał, Jakub. "Influence of Lightning Current Model on Simulations of Overvoltages in High Voltage Overhead Transmission Systems." Energies 13, no. 2 (January 7, 2020): 296. http://dx.doi.org/10.3390/en13020296.

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The analysis of lightning overvoltages generated in electrical power systems has a great meaning for the designers and exploitation engineers because it creates bases for the optimization of construction overhead transmission lines and high voltage substations, reducing costs and increasing reliability of the transmission and distribution of electrical energy. Lightning overvoltages generated in electrical power systems with overhead transmission lines are a result of complex, nonlinear, and surge phenomena occurring in the structure of line towers and electrical substation when the lightning current is flowing through them. Methods of overvoltage stress analysis are intensely developed, and one of the directions is working out models of high voltage electrical devices and phenomena in electrical networks, which influence the shape and values of overvoltage risks. The model of lightning current has a significant influence on the courses of overvoltages in high voltage transmission systems. The paper is focused on the analysis of the influence of the model of lightning current making use of simulations of the shape, and maximal values of overvoltages generated in high voltage transmission systems during a direct lightning strike to the overhead lines. Two models of lightning current used in simulations with the Electromagnetic Transients Program/Alternative Transient Program (EMTP/ATP) were analyzed, i.e., the Heidler model and CIGRE (Conseil International des Grands Réseaux Électriques) model. The EMTP/ATP computer program is very often used in simulations of overvoltages in electrical networks. Unfortunately, the users get no information on the criterion to be used when selecting the model of lightning current used in the simulations. The analysis presented in the paper gives practical knowledge about the effect of the use of a particular kind of lightning current model on the results of simulations of lightning overvoltage propagation in electrical networks, overvoltage protection, as well as on theoretical and practical aspects of the insulation coordination in high voltage transmission systems.

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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 (May 14, 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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Han, Yanzan, and Jimeng Zhang. "Recognition Algorithm of Transient Overvoltage Characteristic Based on Symmetrical Components Estimation." Symmetry 12, no. 1 (January 7, 2020): 114. http://dx.doi.org/10.3390/sym12010114.

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The recognition of transient overvoltage characteristics is the premise of disturbance compensation of the transient overvoltage. Based on that, the recognition algorithm of transient overvoltage characteristics based on symmetrical components estimation was proposed. The generation mechanism of the transient overvoltage in gas insulated switchgear (GIS) was analyzed. Then, the transient overvoltage was measured via the capacitive sensor method. The three-phase voltage of ultra-high voltage grid was asymmetrical when the transient overvoltage appeared. At present, the asymmetrical three-phase voltage was decomposed into the superposition of a symmetrical positive-sequence component, a negative-sequence component, and a zero-sequence component via the symmetrical components estimation to build the superposition model. The model was decomposed via the trigonometric identity and the modified neural network of the least mean square learning rule was used to estimate the parameter vector of the characteristic quantity of the transient overvoltage in real time. The feasibility of the proposed algorithm was verified via comparing the simulation of the proposed algorithm and the algorithm based on dp transformation. The experimental results show that the proposed algorithm has the advantages of a small operand, high detection precision, and fast action.

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Hanus, Oleksii, and Kostiantyn Starkov. "STUDY OF THE NATURE OF OVERVOLTAGES IN THE ELECTRICAL NETWORK ARISING FROM VOLTAGE TRANSFORMERS." Bulletin of the National Technical University "KhPI". Series: Energy: Reliability and Energy Efficiency, no. 1 (2) (July 2, 2021): 28–36. http://dx.doi.org/10.20998/2224-0349.2021.01.05.

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A non-linear dynamic mathematical model of voltage transformer has been considered and overvoltages arising on the elements of voltage transformer equivalent circuit during transient processes have been investigated. The influence of voltage transformer secondary circuit capacitance on overvoltage multiplicity in the primary circuits and the duration of transients has been determined. The advantages of approximation of nonlinearity of voltage transformers by hyperbolic sine are used. Mathematical expressions determining the nature of changes in the forced and free components of the transient process in an electrical network with a voltage transformer have been obtained. It is shown that with the increase of the electric network capacitance the duration of the transition process damping increases and the frequency of the forced oscillations and the level of overvoltage decrease. It is proved that even small, in comparison with the primary nominal sinusoidal voltage, aperiodic components of the voltage transient process can lead to significant overvoltages during voltage transformer outages. It has been substantiated that both the secondary resistance and the switching torque influence the overvoltage multiplicity arising in the primary winding of voltage transformers. It is shown that the closed secondary winding worsens the disconnection process of non-linear inductance of voltage transformers. The values to which overvoltages increase in this case are determined. According to the results of calculations it is determined that with open secondary winding of voltage transformers the duration of transient process significantly increases. It has been found that the decrease of frequency of forced oscillations, which occurs in this case, is accompanied by an increase of currents in the primary winding of the voltage transformer, which is dangerous in terms of thermal stability of the winding insulation. It is shown, that closing the secondary winding of voltage transformers leads to significant reduction of transient damping time. It is suggested that this algorithm can be used to provide a rapid breakdown (suppression) of ferroresonant processes. The effectiveness of such a measure of stopping of ferroresonance processes as short-term shunting of secondary winding of voltage transformers has been investigated. The correlation of parameters of electric networks (capacity of busbar sections, nonlinearity of characteristics of voltage transformers, disconnection torque, etc.) at which ferroresonance process may occur and consideration of which may allow, in terms of prevention of ferroresonance processes, to identify substations (electric networks) that require more detailed research has been determined. The results of analytical studies were tested in the electric networks of JSC "Kharkivoblenergo" and used in the electricity distribution system for the selection of specific voltage transformers for certain configurations of electrical networks.

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R. S. Gates, L. W. Turner, and D. G. Overhults. "Transient Overvoltage Testing of Environmental Controllers." Transactions of the ASAE 35, no. 2 (1992): 727–33. http://dx.doi.org/10.13031/2013.28655.

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Feng, Man, Tao Li, and Jinjuan Liu. "Transient overvoltage characteristics in submarine cables of multi-terminal flexible HVDC transmission system." Journal of Physics: Conference Series 2108, no. 1 (November 1, 2021): 012046. http://dx.doi.org/10.1088/1742-6596/2108/1/012046.

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Abstract The overvoltage transient characteristics of submarine cables are one of the key technologies for submarine power transmission. This article takes the submarine cable of Zhoushan Multi-terminal Flexible HVDC Transmission Project as the research object. The MMC-HVDC simulation models at both ends of converter stations are built in PSCAD. The parameters and equivalent models of the flexible HVDC cables are determined, and the submarine DC cable operating overvoltage is calculated by using statistical methods. The simulation results show that the maximum overvoltage of the submarine cable, that is, the maximum overvoltage of the conductor to sheath, the sheath to the armour, and the armour to the ground are 400 kV, 7.27 kV and 0.45kV respectively. The maximum overvoltage when it occurs faults on grid-side or valve-side appears in the middle of the submarine cable. Maximum overvoltage of HVDC single pole grounding fault appears at the connection point of land cable and submarine cable. The simulation results and the discovery of features in this article provide reference in the design, selection, and testing of submarine power transmission equipment.

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Pannila, Earl A. R. L., and Mahesh Edirisinghe. "Signatures of Transient Overvoltages in Low Voltage Power Systems in Tea Factories and Their Implications on Insulation Deterioration and Allied Power Quality Issues." Journal of Electrical and Computer Engineering 2021 (November 19, 2021): 1–12. http://dx.doi.org/10.1155/2021/2623965.

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Electrical equipment and supply cables demand a better quality of supply, with the recent advancements in integrated sensitive solid-state controls. Divergently, proliferated heavy inductive motors and some performance additions based on power electronics have introduced power quality issues to the network. Thus, this study mainly investigates the impact of switching transients generated by electromechanical machines in industrial power systems on insulation deterioration while taking transient overvoltages due to capacitor bank switching also to support. Transients with a high rate of rise are likely to catalyze the degradation of the insulation quality and break down the insulating material through ionization. These steeply passing overvoltage stresses let partial discharges ensue, which can attack the insulation over long service. To unveil this danger, 314 common-mode transient waveforms were measured in the electrical machines of five tea factories in Sri Lanka, in a 50 ms measurement window, taken in 55 measuring attempts. Most of the transients observed are in the form of a damped oscillatory waveform tailed by fast exponential collapse. That correlates to insulation degradation having a very steep rise as 30.04 V/ns, the highest at the withering section. When machines are heavily loaded, situations tend to generate transients with high amplitudes. There were transient bursts that spread as 426.3 ms, while 14 ns fast rise times were recorded from withering motors. Unlike electrical resonance and power-frequency overvoltages, electromagnetic switching transients last even less than 100 ms. To underline this, an analysis of the frequency domain of transients was also presented, which proves high density of high-frequency components reaching 107 kHz range. Accepting the fact that frequency and amplitude are always under the influences of innumerable dynamics, the observational evidence of the study endorses that electrical stress built by the transient nature of the factories reduces the life expectancy of electrical insulation.

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Kaczmarek, Michał, and Dariusz Brodecki. "Transformation of Transient Overvoltages by Inductive Voltage Transformers." Sensors 21, no. 12 (June 17, 2021): 4167. http://dx.doi.org/10.3390/s21124167.

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Overvoltage transients occur after any type of switching activity in a power network, such as breaker operation, fault occurrence/clearance and rapid load change. This distortion of voltage is transformed to the secondary circuit of a voltage transformer. The maximum values of such impulses may many times exceed the rated value of its secondary voltage. This can lead to malfunction of measuring or protection devices connected to the secondary circuit of a voltage transformer and even their damage. The paper presents the application of determined values of ratio error at harmonics of the inductive voltage of the transformer to predict the value of transformed slow-front transient overvoltage to their secondary circuits. This will help to prevent malfunction of measuring or protection devices connected to the secondary side of the voltage transformer and increase their safety of operation. The inductive voltage transformer equivalent circuit for transformation of higher frequency components of distorted voltage must be extended with internal capacitances of windings. This is caused by the fact that the resonance phenomenon of the slow-front transient overvoltage results from leakage inductance and capacitance of primary winding, not from the magnetic core. Therefore, this behaviour is independent from the value of the applied voltage.

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Yang, Mingkai, Yuanyuan Li, Baomin Fang, Xin Zhang, and Chunmeng Chen. "Power grid practice of suppressing transient overvoltage of sending-end system by ultra high voltage direct current control parameters." Journal of Physics: Conference Series 2310, no. 1 (October 1, 2022): 012036. http://dx.doi.org/10.1088/1742-6596/2310/1/012036.

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Abstract The transient overvoltage off-grid problem of new energy in the sending-end network has become an important factor limiting the ultra high voltage direct current (UHVDC) transmission capacity. In this paper, the causes of transient overvoltage during the DC fault process is analysed firstly, then from the perspective of adjusting the reactive power consumption of the converter, taking the Qingyu UHVDC project in China as an actual simulation example, the influence of the DC control mode and current control parameters at the rectifier side on the transient overvoltage is deeply studied. Combined with the transient voltage evaluation results of the actual power grid, guiding suggestions for DC control strategies are given to improve the transmission capacity. The research results have important reference significance for improving the consumption of new energy and the transmission capacity of UHVDC projects.

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Nie, Yu, Guoqing Zhang, Jiakuo Song, and Guizhong Wang. "Simulation and Experimental Research on Overvoltage Measurement of Hybrid CVT." E3S Web of Conferences 256 (2021): 01016. http://dx.doi.org/10.1051/e3sconf/202125601016.

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The CVT equipment running on site is slightly modified to form a hybrid CVT to achieve transient overvoltage measurement, which is theoretically feasible and practical. In order to study the voltage division method based on the hybrid CVT to measure the overvoltage of the power system, that is, the low voltage capacitor C3 is connected in series between the low voltage terminal of the medium voltage capacitor C2 of the traditional CVT and the ground, and the transient overvoltage measurement is realized through C3. This article uses ATP-EMTP to establish its high-frequency transient model for simulation analysis. For further verification, a power frequency voltage test and an impulse voltage test were carried out on the 110kV hybrid CVT produced by Taikai Transformer Factory, focusing on the analysis of the partial voltage characteristics of the capacitor C3. The simulation results show that the C3 partial pressure method can achieve a relatively accurate measurement of the transient overvoltage. The test results show that the voltage across C3 is affected by uncertain factors and has an impact phenomenon. The above analysis process and results have certain practical value for designing actual products.

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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 (February 17, 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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Wen, Ding Jun, Xiu Bin Zhang, Hong Gang Chen, Feng Jiang, and Ya Ming Sun. "Impact of 750kV Transmission Line Series Compensation Capacity on Power Frequency Overvoltage." Advanced Materials Research 986-987 (July 2014): 330–33. http://dx.doi.org/10.4028/www.scientific.net/amr.986-987.330.

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The overvoltage calculation of 750kV transmission line with series compensation has great significance on the design, insulation coordination and protection of the line. In this paper, a transient model of 750kV power transmission system with series compensation is established. Effects of different capacity on no-load capacitive rise overvoltage, single-phase grounding overvoltage, two-phase grounding overvoltage are calculated. Secondary arc current and recovery voltage of different series compensation capacity in single-phase grounding is also calculated.

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Stanchev, Plamen Antonov. "Investigation of the Overvoltages in Electrical Power Lines with a Grounded through a Resistance Neutral." ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA 4, no. 1 (June 30, 2020): 73–78. http://dx.doi.org/10.29114/ajtuv.vol4.iss1.174.

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The paper examines the variation of electrical variables during phase-to-ground faults on medium voltage electrical power lines with a grounded through a resistance neutral. The studies were performed with simulation models of a medium voltage electrical power line. The parameters under consideration have been the voltages and the currents in the transient and steady state operation of the line and more precisely their dependence on the variation of the arc resistance in the place of the fault and the distance from the fault to the supply source. Calculated, accordingly, is the overvoltage during the transient process, the maximum magnitude of the overvoltage and phase-to-earth fault current, the duration of the transient phase-to-ground fault current as well as the maximum magnitude of the overvoltage оn the neutral.

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Peng, Guoping, Chuanming Fu, Ping Yang, Ben Shi, Hongzhan Wang, Jun Zeng, and Yangbo Liu. "Research on Lightning Overvoltage Characteristics of High-Voltage Diode Rectifier." Electronics 11, no. 23 (November 22, 2022): 3840. http://dx.doi.org/10.3390/electronics11233840.

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Failure of the high-voltage diode rectifier caused by lightning will cause huge losses. The traditional analysis of overvoltage induced by the high-voltage diode rectifier shell under lightning stroke cannot adapt to the overvoltage process caused by lightning stroke-induced conduction invading the inside of the high-voltage diode rectifier. Therefore, this paper proposes to establish a high-frequency equivalent model of the core components of the high-voltage diode rectifier, including diodes, reactors, transformers, and overhead lines. On this basis, a lightning overvoltage model of lightning-induced conduction into the high-voltage diode rectifier is built, and the transient process of diode lightning overvoltage under the constraint of reverse recovery charge is analyzed. Then, we describe the transient distribution of overvoltage in high-voltage diode rectifiers caused by lightning stroke. The transient distribution of overvoltage induced by lightning in series diodes under different diode equivalent models is analyzed by simulation. The simulation results show that the inconsistent parameters of series diodes can easily lead to diode damage due to uneven voltage distribution when lightning strikes. Therefore, this paper puts forward a scheme to reduce lightning damage, including selecting diodes with the same parameters and adding fast-melting fuses at the transformer’s secondary side and in front of the series diode bridge arm. The simulation shows that the scheme proposed in this paper can effectively prevent the high-voltage diode rectifier from being damaged by lightning strikes.

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Long, Chen, Yifei Wu, Yang Yang, Zhaomin Yao, Yu Xiao, Qiong Kang, Feng Zhang, and Chuangchuang Tao. "Study on Overvoltage Rise Rate Suppression Method for DC Interruption." Journal of Physics: Conference Series 2213, no. 1 (March 1, 2022): 012023. http://dx.doi.org/10.1088/1742-6596/2213/1/012023.

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Abstract DC circuit breaker is the key equipment for control and protection in the medium and high voltage DC system. Mechanical DC circuit breakers have transient overvoltage in breaking, which may lead to re-breakdown of the breaker or even breaking failure in severe cases. In this paper, the transient overvoltage in the breaking process of typical mechanical DC circuit breakers is studied. An improved topology which can supress the transient voltage is propose. The effect of different capacitance and resistance parameters on weakening the transient voltage is investigated, and the adaptability of the proposed method to different breaking currents is studied.

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Ren, Hongtao, and Jianfeng Chen. "Study on lightning impulse voltage distribution and Transfer Overvoltage of 500kV transformer." Journal of Physics: Conference Series 2260, no. 1 (April 1, 2022): 012013. http://dx.doi.org/10.1088/1742-6596/2260/1/012013.

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Abstract Lightning shock wave acts on transformer, and the electromagnetic field in transformer winding is very complex. Due to the electromagnetic oscillation inside the winding, overvoltage will be produced on the main insulation or longitudinal insulation of the transformer, and the potential gradient at the end of the winding is very large, so that the insulation of the transformer is broken down. Therefore, the impact resistance of insulation should be considered in the insulation design of transformer. The amplitude and distribution of overvoltage in transformer winding will affect the selection of insulation material and insulation structure. At the same time, the analysis of transient overvoltage in transformer winding can also provide a theoretical basis for lightning warning system of power system. In order to understand the distribution of transient overvoltage in transformer winding, this paper analyzes the models of cake winding by computer simulation.

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Niu, Shuanbao, Xianbo Ke, Qiang Shen, Chao Huo, Ning Chen, and Hua Li. "Research on Transient Overvoltage Suppression Measures for Photovoltaics Connected to the DC Sending End in the Smart Power System for Industry 4.0." Mathematical Problems in Engineering 2020 (October 14, 2020): 1–13. http://dx.doi.org/10.1155/2020/4585297.

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The development of smart power systems in Industry 4.0 will bring people better quality electrical energy. The photovoltaic power generation system in the smart grid for Industry 4.0 is also the focus of development. The rapid development of photovoltaic power generation systems will bring people cleaner and greener energy. However, it will cause the transient overvoltage phenomenon near the DC sending terminal when the large-scale photovoltaic plant is connected to the power grid, further bringing about a profound impact on the power grid and its security and stability. In this paper, it is proposed that the rise of transient overvoltage at the photovoltaic terminal is caused by three main factors including the reactive power surplus of DC commutation failure, the weak power grid at the sending terminal, and the control characteristics of the photovoltaic plant. Then, the coordinated control strategy of transient overvoltage is proposed, and the overvoltage control strategy of the DC transmission terminal and the photovoltaic power plant control strategy are, respectively, optimized. Finally, the influence parameters of overvoltage are analysed and the corresponding photovoltaic strategy is presented. The optimization results of photovoltaic parameters and the proposed strategies of photovoltaic power generation can effectively restrain the voltage or frequency fluctuation and power oscillation caused by HVDC commutation failure. This study promotes the development of the photovoltaic power generation system in the intelligent power system of industry 4.0.

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Standler, R. B. "Equations for some transient overvoltage test waveforms." IEEE Transactions on Electromagnetic Compatibility 30, no. 1 (1988): 69–71. http://dx.doi.org/10.1109/15.19891.

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Adhikari, Prottay M., Luigi Vanfretti, Anja Banjac, Roland Bründlinger, Michael Ruppert, and Michael Ropp. "Analysis of transient overvoltages and Self Protection Overvoltage of PV inverters through RT-CHIL." Electric Power Systems Research 214 (January 2023): 108826. http://dx.doi.org/10.1016/j.epsr.2022.108826.

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Zhao, Pengcheng, Jingang Wang, Qian Wang, Qianbo Xiao, Ruiqiang Zhang, Shucheng Ou, and Yaqin Tao. "Simulation, Design, and Test of a Dual-Differential D-Dot Overvoltage Sensor Based on the Field-Circuit Coupling Method." Sensors 19, no. 15 (August 3, 2019): 3413. http://dx.doi.org/10.3390/s19153413.

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Accurate measurement of overvoltage in power grids is of great significance to study the characteristics of overvoltage and design of insulation coordination. Based on the research of D-dot voltage sensor, we designed a Dual-Differential D-dot overvoltage sensor. In order to quantify the structural parameters of the sensor, improve the performance and measurement accuracy of the sensor. The Field-Circuit Coupling method was proposed to be used in the parameter design of D-dot overvoltage sensor. The joint simulation of space electromagnetic field model and equivalent circuit model of the Dual-Differential D-dot overvoltage sensor was established with the finite element simulation software Ansoft Maxwell and circuit simulation software Simplorer. Finally, the actual sensor was manufactured. A test platform was built to verify the steady-state and transient performance of the sensor. The results show that the Dual-Differential D-dot sensor has excellent steady-state and transient performance, the error of phase and amplitude are small, and the sensor can achieve the non-contact measurement of power transmission line. Simultaneously, the rationality of the Field-Circuit Coupling method was further verified.

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Li, Yecheng, Pengcheng Guo, Wenbin Zhuang, Zhiqiang Li, Chengxiang Huo, Jiahuan Zhang, Lei Yue, and Ancheng Xue. "A Dynamic Reactive Power Allocation Method for Sending-End Power System of the UHVDC Delivering Large Terminal of Renewable Energy." Mathematical Problems in Engineering 2023 (February 4, 2023): 1–12. http://dx.doi.org/10.1155/2023/9764844.

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Allocation of reactive power equipment can relieve the transient overvoltage, which is a big threat to the sending-end electric power system of ultrahigh-voltage direct current (UHVDC). However, the dynamic reactive power allocation mostly depends on the trial-and-error method, lacking in an optimal allocation method based on the quantitative evaluation index. To deal with the abovementioned problem, in this study, a dynamic reactive power optimal allocation method is proposed based on the reactive power compensation sensitivity. In detail, first, based on the existing transient overvoltage assessment index, the general form of reactive power optimization problem is proposed. Then, taking the sending-end power system of UHVDC as an example, the reactive power allocation location is determined based on a reactive power compensation sensitivity. Furthermore, combined with the sensitivity, the compensation capacity of each place is determined by particle swarm optimization (PSO). The simulation results show that the proposed method can effectively allocate the dynamic reactive power and suppress the transient overvoltage after fault.

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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 (January 8, 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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Sarajcev, Petar, Antun Meglic, and Ranko Goic. "Lightning Overvoltage Protection of Step-Up Transformer Inside a Nacelle of Onshore New-Generation Wind Turbines." Energies 14, no. 2 (January 8, 2021): 322. http://dx.doi.org/10.3390/en14020322.

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This paper presents an electromagnetic transient analysis of lightning-initiated overvoltage stresses of the step-up transformers installed inside a nacelle of onshore, multi-megawatt, new-generation wind turbines. The increase in the wind turbine (WT) nominal power output, necessitated introducing the step-up transformer into the nacelle. A transformer installed inside a nacelle is subjected to completely different overvoltage stresses from those present if it were installed at the base of the WT tower. This has serious repercussions on its overvoltage protection (i.e., selection and installation of surge arresters) and insulation coordination. Furthermore, the overvoltage protection of medium-voltage cables (inside the tower) is also problematic when considering their length, proximity to the tower wall, and their screen grounding practices, and needs to be tackled in conjunction with that of the step-up transformer. This paper presents detailed models for the various components of the latest-generation WTs, intended for fast-front transient analysis and assembled within the EMTP software package. We further present the comprehensive results of the lightning-transient numerical simulations, covering both upward and downward (first and subsequent) strikes, their analysis, and recommendations for the optimal selection of medium-voltage surge arresters for the step-up transformers installed inside a nacelle.

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Sarajcev, Petar, Antun Meglic, and Ranko Goic. "Lightning Overvoltage Protection of Step-Up Transformer Inside a Nacelle of Onshore New-Generation Wind Turbines." Energies 14, no. 2 (January 8, 2021): 322. http://dx.doi.org/10.3390/en14020322.

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This paper presents an electromagnetic transient analysis of lightning-initiated overvoltage stresses of the step-up transformers installed inside a nacelle of onshore, multi-megawatt, new-generation wind turbines. The increase in the wind turbine (WT) nominal power output, necessitated introducing the step-up transformer into the nacelle. A transformer installed inside a nacelle is subjected to completely different overvoltage stresses from those present if it were installed at the base of the WT tower. This has serious repercussions on its overvoltage protection (i.e., selection and installation of surge arresters) and insulation coordination. Furthermore, the overvoltage protection of medium-voltage cables (inside the tower) is also problematic when considering their length, proximity to the tower wall, and their screen grounding practices, and needs to be tackled in conjunction with that of the step-up transformer. This paper presents detailed models for the various components of the latest-generation WTs, intended for fast-front transient analysis and assembled within the EMTP software package. We further present the comprehensive results of the lightning-transient numerical simulations, covering both upward and downward (first and subsequent) strikes, their analysis, and recommendations for the optimal selection of medium-voltage surge arresters for the step-up transformers installed inside a nacelle.

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Zhang, Zhong Yuan, Xin Ge, and Zeng Chao Wang. "Research on Nonlinear Modeling for Power Transformer over Wide Frequency Range." Applied Mechanics and Materials 446-447 (November 2013): 832–36. http://dx.doi.org/10.4028/www.scientific.net/amm.446-447.832.

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This paper proposes a new nonlinear broadband model of the power transformer which is both fit for steady state and transient simulation in power system. The model consists of high-frequency module and low-frequency module in parallel. Based on the black-box method, the high-frequency block is built in the form of π-type equivalent circuit, and the low-frequency block is in the form of conventional gamma-type circuit, in which core saturation characteristic is expressed by a nonlinear inductor. A power transformer is studied in the laboratory, simulations and experiments are carried out in case of power-frequency steady state, excitation currents distortions, lightning overvoltage, and very fast transient overvoltages (VFTO) respectively. The comparisons between the simulated and measured results verify the feasibility and validity of the model.

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Pramana, Putu Agus Aditya, Aristo Adi Kusuma, Buyung Sofiarto Munir, and Handrea Bernando Tambunan. "Covered conductor burn-down prevention for distribution line in Indonesia." MATEC Web of Conferences 197 (2018): 11003. http://dx.doi.org/10.1051/matecconf/201819711003.

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Covered conductor (CC) is used to resolve temporary line to ground fault in the distribution line. However, some cases of CC burn down were found in Indonesia. These phenomena were triggered by lightning strikes that cause transient overvoltage with a magnitude greater than basic insulation level (BIL) of insulator. Consequently, short circuit current will flow through the pinhole on CC. Burn down phenomena will create high impedance fault that is unable to be detected by protection relay, thus the conductor will remain energized and harmful to the surroundings. Therefore, this paper presents study about CC burn down prevention. The study was performed using transient simulation to find the effect of earth wire utilization against the transient overvoltage due to lightning strike. In addition, finite element simulation and laboratory testing were also performed to analyze the effect of power arc device on burn down prevention. The results show that the lightning strike with negative polarity will not cause transient overvoltage with a magnitude greater than the insulator BIL. However, if the lighting strikes have positive polarity then the insulator BIL will be potentially exceeded. Furthermore, the utilization of power arc device will prevent the CC burn down.

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Ma, Guo-Ming, Cheng-Rong Li, Wei-Jiang Chen, Min Chen, Ze-Lai Sun, Wei-Dong Ding, and Zhi-Bing Li. "Very Fast Transient Overvoltage Measurement With Dielectric Window." IEEE Transactions on Power Delivery 29, no. 5 (October 2014): 2410–16. http://dx.doi.org/10.1109/tpwrd.2014.2320749.

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LIU, YING, and CHI XIE. "IMAGE RECOVERY OF TRANSIENT VOLTAGE BASED ON REAL-TIME MONITORING." Modern Physics Letters B 22, no. 05 (February 20, 2008): 353–58. http://dx.doi.org/10.1142/s0217984908014821.

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In modern high-energy physics, a powerful electromagnetic field must be supplied for some elementary particles to be accelerated by passing through the region of high-energy physics fields. The electric current and high voltage producing the powerful electromagnetic field are very important to high-energy accelerators, but the insulation of electromagnetic coils in the accelerators suffers from electric damage under powerful electricity. Epecially, it may be stricken by transient overvoltage from the a.c. generator or electric network at any time. For the insulation problem of electromagnetic coils in the accelerator stricken by transient overvoltage, based on real-time monitoring and virtual image technique, the image recovery of transient voltage and the insulation safety of electromagnetic coils in the accelerator can be analyzed and predicted on-line.

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Grigoriev, A. V., L. N. Tokarev, and D. A. Makarov. "Operation of propeller motors composed of ship electric propulsion systems with semiconductor converters." Journal of Physics: Conference Series 2061, no. 1 (October 1, 2021): 012029. http://dx.doi.org/10.1088/1742-6596/2061/1/012029.

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Abstract The calculations of transient processes in ship electric propulsion systems (EPS) with semiconductor converters (SC) show that when the inverter transistors are locked, overvoltage occurs that may break through the insulation of propeller motors (PM). A feature of this overvoltage is its short duration and large value. Pulsed overvoltage of small duration and the EPS value of dozens or more kilovolts may occur in the circuits of the inverter supplying the PM winding. The main cause of overvoltage is the EPS self-induction resulting from rapid current reduction in circuits with inductances, including in motor windings, when the inverter transistors are locked. The paper presents the results of mathematical modeling of the processes arising when the inverter transistors functioning as part of the frequency converter are locked. The results of the analysis confirmed the possibility of overvoltage on the PM winding, which should be taken into account when designing the EPS and selecting equipment.

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Zhou, Zikai, Yaxun Guo, Xiaofeng Jiang, Gang Liu, Wenhu Tang, Honglei Deng, Xiaohua Li, and Ming Zheng. "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 (November 13, 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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Priya. K.R, Anu, and Sasilatha T. "Transformer Exchanging with Vacuum Electrical Switch." Indonesian Journal of Electrical Engineering and Computer Science 8, no. 3 (December 1, 2017): 679. http://dx.doi.org/10.11591/ijeecs.v8.i3.pp679-680.

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<p>This paper presents investigation of conceivable transient overvoltage that can be produced amid vacuum electrical switch (VCB) operation at the association purpose of a photovoltaic power plant. Average exchanging occasion that is identified with VCB concerns stimulation and de-empowerment of emptied transformer. Nonetheless, at the common photovoltaic power plant the transformer is sustained by an inverter outfitted with LC (or LCL) channels that are important for constraint of music and swell in voltage and current. From the perspective of exchanging operations, the inductance and capacitance of the LV side associated channel influence the regular recurrence of the transformer, which is reflected by various transient framework reaction amid VCB working. In this article, research facility estimation of overvoltage produced amid dispersion transformer exchanging by methods for VCB is examined. Effect of the LC channel associated at the LV side on the overvoltage concealment was contemplated. EMTP-ATP recreations were directed with a specific end goal to confirm the likelihood of homeless people end by methods for extra arrangement associated RL gag at the transformer medium voltage side.</p>

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Dong, Hua Ying, Li Ze Xu, Gui Shu Liang, Xin Liu, and Xu Cheng. "Wide-Band Modeling of Grounding Grid Based on the Fractional Order Differential Theory." Advanced Materials Research 860-863 (December 2013): 2292–95. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.2292.

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Research on the wide-band modelling method of the grounding grid and the analysis of the electromagnetic transients on the grounding grid has significant practical meaning on the engineering problems, e.g. overvoltage protection, insulation coordination and electromagnetic interference and the increasing levels of capacity in the power and communication systems. This paper presents strategies which establish the equivalent circuit for computing the transient performance of grounding grid base on fractional order differential theory, which takes into account the fractional frequency characteristics of soil permittivity. In order to validate the presented method, an example is considered and the transient responses are compared with the results obtained by the method of moments.

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35

Yanabu, S., H. Murase, H. Aoyagi, H. Okubo, and Y. Kawaguchi. "Estimation of fast transient overvoltage in gas-insulated substation." IEEE Transactions on Power Delivery 5, no. 4 (1990): 1875–82. http://dx.doi.org/10.1109/61.103684.

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36

Ahmad, A., P. Johannet, and Ph Auriol. "Efficient inverse Laplace transform algorithm for transient overvoltage calculation." IEE Proceedings C Generation, Transmission and Distribution 139, no. 2 (1992): 117. http://dx.doi.org/10.1049/ip-c.1992.0019.

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37

Shibuya, Y., S. Fujita, and N. Hosokawa. "Analysis of very fast transient overvoltage in transformer winding." IEE Proceedings - Generation, Transmission and Distribution 144, no. 5 (1997): 461. http://dx.doi.org/10.1049/ip-gtd:19971134.

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38

Xu, Cuidong, Zhu Chen, Ka Cheng, Xiaolin Wang, and Ho Ho. "A Supercapacitor-Based Method to Mitigate Overvoltage and Recycle the Energy of Pantograph Arcing in the High Speed Railway." Energies 12, no. 7 (March 28, 2019): 1214. http://dx.doi.org/10.3390/en12071214.

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The pantograph arcing phenomenon may shorten the service life of a pantograph and even destroy onboard devices and instruments, due to the irregular motions of the train and the intermittent line–pantograph disconnection. This paper points out that abrupt inductive energy from the magnetizing inductance of the traction transformer can lead to an electromagnetic transient process with unexpected overvoltage across it. Further, a supercapacitor-based power electronic system is proposed, which can not only redirect the inductive energy to the supercapacitor pack through bidirectional converters but also mitigate the overvoltage across the main electrical equipment when pantograph arcing occurs. Simulation results show the overvoltage could be reduced and the energy stored in the supercapacitor which could also be used to provide energy for sensors or other devices.

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Duggirala, V. N. Ananth, and V. Nagesh Kumar Gundavarapu. "Dynamic Stability Improvement of Grid Connected DFIG Using Enhanced Field Oriented Control Technique for High Voltage Ride Through." Journal of Renewable Energy 2015 (2015): 1–14. http://dx.doi.org/10.1155/2015/490178.

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Doubly fed induction generator (DFIG) is a better alternative to increased power demand. Modern grid regulations force DFIG to operate without losing synchronism during overvoltages called high voltage ride through (HVRT) during grid faults. Enhanced field oriented control technique (EFOC) was proposed in Rotor Side Control of DFIG converter to improve power flow transfer and to improve dynamic and transient stability. Further electromagnetic oscillations are damped, improved voltage mitigation and limit surge currents for sustained operation of DFIG during voltage swells. The proposed strategy has advantages such as improved reactive power control, better damping of electromagnetic torque oscillations, and improved continuity of voltage and current from stator and rotor to grid during disturbance. In EFOC technique, rotor flux reference changes its value from synchronous speed to zero during fault for injecting current at the rotor slip frequency. In this process, DC-Offset component of stator flux is controlled so that decomposition during overvoltage faults can be minimized. The offset decomposition of flux will be oscillatory in a conventional FOC, whereas in EFOC it is aimed to be quick damping. The system performance with overvoltage of 1.3 times, 1.62 times, and 2 times the rated voltage occurring is analyzed by using simulation studies.

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Barzkar, Ashkan, and Mona Ghassemi. "Precise Evaluation of Repetitive Transient Overvoltages in Motor Windings in Wide-Bandgap Drive Systems." Vehicles 4, no. 3 (July 19, 2022): 697–726. http://dx.doi.org/10.3390/vehicles4030040.

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The increasing interest in employing wide-bandgap (WBG) drive systems has brought about very high power, high-frequency inverters enjoying switching frequencies up to hundreds of kilohertz. However, voltage surges with steep fronts, caused by turning semiconductor switches on/off in inverters, travel through the cable and are reflected at interfaces due to impedance mismatches, giving rise to overvoltages at motor terminals and in motor windings. The phenomena typically associated with these repetitive overvoltages are partial discharges and heating in the insulation system, both of which contribute to insulation system degradation and may lead to premature failures. In this article, taking the mentioned challenges into account, the repetitive transient overvoltage phenomenon in WBG drive systems is evaluated at motor terminals and in motor windings by implementing a precise multiconductor transmission line (MCTL) model in the time domain considering skin and proximity effects. In this regard, first, a finite element method (FEM) analysis is conducted in COMSOL Multiphysics to calculate parasitic elements of the motor; next, the vector fitting approach is employed to properly account for the frequency dependency of calculated elements, and, finally, the model is developed in EMTP-RV to assess the transient overvoltages at motor terminals and in motor windings. As shown, the harshest situation occurs in turns closer to motor terminals and/or turns closer to the neutral point depending on whether the neutral point is grounded or floating, how different phases are connected, and how motor phases are excited by pulse width modulation (PWM) voltages.

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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 (December 8, 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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Chinges, Tserensambuu, Qingmin Li, and Jiyao Zhao. "Lightning Transient Analysis Comparison and Wind Turbine Models Using PSCAD/EMTDC Circuit Simulator." Journal of Physics: Conference Series 2320, no. 1 (August 1, 2022): 012020. http://dx.doi.org/10.1088/1742-6596/2320/1/012020.

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Abstract This paper aims to compute the lightning electromagnetic transient overvoltage and current on the wind turbine using the PSCAD/EMTDC simulation program. The double-peaked lightning current, tower, grounding system models, and dangerous situation of the grounding system are investigated by the PSCAD simple circuit branch segment codes and defining components. A comparison analysis has been performed to see the influence of lightning current wave shapes and grounding characteristics. The simulation results show that 43 kA and 31 kA lightning currents produce 200 kV overvoltage on the turbine grounding in case of 1000 Ω·m soil resistivity. However, current amplitudes on the equipotential grounding system become 28 kA and 20 kA. The influencing factors of the surge protection device are determined using good accuracy computer simulation.

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He, Huiwen, Lei Wang, Peihong Zhou, and Fei Yan. "Overvoltage and Insulation Coordination of Overhead Lines in Multiple-Terminal MMC-HVDC Link for Wind Power Delivery." International Journal of Rotating Machinery 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/4849262.

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The voltage-sourced converter-based HVDC link, including the modular multilevel converter (MMC) configuration, is suitable for wind power, photovoltaic energy, and other kinds of new energy delivery and grid-connection. Current studies are focused on the MMC principles and controls and few studies have been done on the overvoltage of transmission line for the MMC-HVDC link. The main reason is that environmental factors have little effect on DC cables and the single-phase/pole fault rate is low. But if the cables were replaced by the overhead lines, although the construction cost of the project would be greatly reduced, the single-pole ground fault rate would be much higher. This paper analyzed the main overvoltage types in multiple-terminal MMC-HVDC network which transmit electric power by overhead lines. Based on ±500 kV multiple-terminal MMC-HVDC for wind power delivery project, the transient simulation model was built and the overvoltage types mentioned above were studied. The results showed that the most serious overvoltage was on the healthy adjacent line of the faulty line caused by the fault clearing of DC breaker. Then the insulation coordination for overhead lines was conducted according to the overvoltage level. The recommended clearance values were given.

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44

Mendis, S. R., and D. A. Gonzalez. "Harmonic and transient overvoltage analyses in arc furnace power systems." IEEE Transactions on Industry Applications 28, no. 2 (1992): 336–42. http://dx.doi.org/10.1109/28.126739.

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Woivre, V., J. P. Arthaud, A. Ahmad, and N. Burais. "Transient overvoltage study and model for shell-type power transformers." IEEE Transactions on Power Delivery 8, no. 1 (1993): 212–22. http://dx.doi.org/10.1109/61.180339.

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Suresh Babu, B. N., and H. B. Wollman. "Transient and overvoltage recovery testing of analog-to-digital converters." IEEE Transactions on Instrumentation and Measurement 44, no. 1 (1995): 53–60. http://dx.doi.org/10.1109/19.368103.

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Paul, D., and V. Haddadian. "Transient Overvoltage Protection of Shore-to-Ship Power Supply System." IEEE Transactions on Industry Applications 47, no. 3 (May 2011): 1193–200. http://dx.doi.org/10.1109/tia.2011.2125772.

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Ogawa, S., E. Haginomori, S. Nishiwaki, T. Yoshida, and K. Terasaka. "Estimation of Restriking Transient Overvoltage on Disconnecting Switch for GIS." IEEE Power Engineering Review PER-6, no. 4 (April 1986): 36–37. http://dx.doi.org/10.1109/mper.1986.5527717.

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Ogawa, S., E. Haginomori, S. Nishiwaki, T. Yoshida, and K. Terasaka. "Estimation of Restriking Transient Overvoltage on Disconnecting Switch for GIS." IEEE Transactions on Power Delivery 1, no. 2 (1986): 95–102. http://dx.doi.org/10.1109/tpwrd.1986.4307939.

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Okabe, S., M. Koto, F. Endo, and K. Kobayashi. "Insulation characteristics of GIS spacer for very fast transient overvoltage." IEEE Transactions on Power Delivery 11, no. 1 (1996): 210–18. http://dx.doi.org/10.1109/61.484018.

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Journal articles on the topic 'Transient overvoltage'

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