Results 21 to 30 of about 370 (172)

A Review of Research Progress in Very Fast Transient Overvoltage (VFTO) Suppression Technology

Energies
The very fast transient overvoltage (VFTO) is characterized by steep wavefronts, high amplitude, and wide spectrum. These characteristics can lead to partial discharges or insulation breakdowns in potted insulators, which can lead to localized ...
Huan Wang, Yinglong Diao, Xixiu Wu, Bolun Du   +3 more
doaj   +2 more sources

Dispersion characteristics of switching transients from large‐scale experiments in a 1100 kV gas insulated switchgear circuit

High Voltage, Volume 8, Issue 6, Page 1253-1263, December 2023., 2023
The switching operation of gas insulated switchgear (GIS) disconnector will produce multiple random spark discharges between the gas gaps of the disconnector.
Jiangong Zhang, Zheyuan Gan, Weijiang Chen, Kejie Li, Jun Zhao, Zhenghai Liao, Zihan Teng, Baoquan Wan   +7 more
core   +2 more sources

A novel embedded voltage‐clamped circuit for multilevel modular converters submodule to suppress very fast transient overvoltage

High Voltage, Volume 9, Issue 6, Page 1202-1207, December 2024.
The submodule in multilevel modular converters experiences a very fast transient overvoltage (VFTO) during switch operation of gas‐insulated switchgear, which also results in overvoltage on power devices, such as thyristors and insulated gate bipolar ...
Zifan Dong, Hong Shen, Yao Yao, Jiayi Shao, Lei Qi, Mian Xiao, Zhonghao Dongye, Xiangyu Zhang   +7 more
core   +2 more sources

Influence of Switching Conditions on the VETO Magnitudes in a GIS [PDF]

IEEE Power Engineering Review, 2001
Estimation of very fast transient overvoltage (VFTO) has been carried out using EMTP for various switching conditions in a 420 kV gas-insulated substation (GIS). The variation of the VFTO peak along the GIS bus nodes for disconnector and circuit breaker switching operations, as well as the variation of VFTO peak with different magnitudes of trapped ...
Kumar, VV, Thomas, JM, Naidu, MS
openaire   +3 more sources

The Optimization Design of VFTO Measuring Method

DEStech Transactions on Engineering and Technology Research, 2017
Whether VFTO can be fast accurate measured becomes an important index of GIS substation equipment safety. The research in this article used the optical voltage measuring method, through the simulation results of single photon road to analyze the advantages and disadvantages, furthermore the double optical path method was put forward, and by the ...
Xue-geng CHEN, Hui-bin SUI, Ying-chao LI, Shu-jiang LI   +3 more
openaire   +3 more sources

Restrike characteristics of vacuum circuit breaker in its opening process under DC voltage

IET Science, Measurement &Technology, Volume 17, Issue 8, Page 297-307, October 2023., 2023
In this paper, a withstand voltage test platform of 40.5‐kV vacuum circuit breaker was established to obtain the effects of the contact spacing and loop and inrush currents of vacuum circuit breaker on the number of restrike, the wavefront steepness of the breakdown voltage, and the breakdown duration.
Jixing Sun, Yongzhi Fan, Jiyong Liu, Jindong Huo, Sibo Song, Yujian Ding, Yu Tian, Huili Wang, Nana Wu   +8 more
wiley   +1 more source

A low‐cost and high‐performance self‐trigger method for high‐voltage transient measurement

High Voltage, Volume 8, Issue 2, Page 412-420, April 2023., 2023
Abstract Stable triggering of acquisition devices is critical to accurately measure electromagnetic transients, especially for very fast transient overvoltages (VFTOs). A highly stable and low‐cos t self‐trigger method for transient measurement is proposed.
Hao Liu, Guoming Ma, Weiqi Qin, Wei Wang, Houxian Du, Lei Wang, Shicong Zhai, Fuping Zeng, Weixing Han   +8 more
wiley   +1 more source

A quantitative research on the level of disturbance to secondary signal ports of electronic voltage transformers under the operation of gas‐insulated switchgear

High Voltage, Volume 7, Issue 1, Page 165-175, February 2022., 2022
Abstract The collectors of electronic transformers has the problem of electromagnetic incompatibility under the operation of disconnecting switches, which limits their wide application in smart grids. To evaluate the maximum level of disturbance that collectors are able to withstand in the stochastic process of switching operation, this work introduces
Qi Wang, Chao Fu, Fanwu Chu, Yue Tong, Xiaozhou Wang, Guoxiong Ye, Xiong Wu   +6 more
wiley   +1 more source

Study on Very Fast Transient Overvoltage Characteristics of Gas‐Insulated Switchgear Substation Based on Hybrid Reactive Power Compensation

Mathematical Problems in Engineering, Volume 2022, Issue 1, 2022., 2022
In recent years, gas‐insulated switchgear (GIS) substations have become widely used in power systems. Due to their compact structure, extremely high oscillation frequencies are prone to extremely high oscillation transient overvoltages or very fast transient overvoltages (VFTOs) when the isolating switch or circuit breaker is operated.
Caiquan Wen, Zheng Yang, Yitao Lu, Yongfeng Huang, Hanliang Lin, Zhiyuan Zhang, Taiyu Chen, Yingnan Liu, Bo Yang   +8 more
wiley   +1 more source

Interference to the Secondary Cable Caused by a Very Fast Transient Overvoltage in a Gas‐Insulated Switchgear Substation

Mathematical Problems in Engineering, Volume 2022, Issue 1, 2022., 2022
When a very fast transient overvoltage (VFTO) propagates in a high‐voltage bus, the capacitive voltage transformer (CVT) causes considerable interference on its secondary side, which will affect the normal operation of the secondary equipment. In this article, a CVT equivalent calculation circuit model was established, and the disturbance voltage of ...
Hanliang Lin, Zhiyuan Zhang, Hongshun Liu, Yifan Wang, Yingnan Liu, Dayang Yu, Qiuqin Sun   +6 more
wiley   +1 more source