Results 51 to 60 of about 1,320 (184)

Breakdown process on rod–rod air gap under oscillating lightning impulse voltage

High Voltage, 2020
This study presents the discharge process on rod–rod electrodes under oscillating lightning impulse voltage. For this purpose, a measurement system has been developed to record the discharge currents at both rod electrodes simultaneously and to ...
Akif Gürlek
doaj   +1 more source

Lightning Impulse Voltage Stresses In Underground Cables

Journal of Physics: Conference Series, 2023
Abstract Underground power cables are crucial for transmission and distribution. Lightning can stress their insulation, but not directly. So, impulse cable testing is studied. This research examines the cable’s transient response to standard and non-standard lightning impulse voltage waveforms.
M S Laili, C M L Fen, M Isa, SNM Arshad, Z N Zakaria   +4 more
openaire   +1 more source

Trends in thunderstorm days, lightning activity, squalls and the environmental factors in Hong Kong

Weather, EarlyView.
This study analyses trends in Hong Kong's convective weather using long‐term observer‐based and shorter‐term instrument‐based data. Annual thunderstorm days increased significantly by 1.9 days decade−1 in 1947–2024, notably in June–September, consistent with increasingly favourable warm‐season environments for thunderstorms.
Yuk Sing Lui, Kin‐chung Hui, Chun‐wing Choy, Pak‐wai Chan, Ming‐chun Lam, Kin‐yu Chan   +5 more
wiley   +1 more source

Evaluation Methodology, Numerical Verification and Retrofilling Procedure for Power Transformers to Ensure K‐Class Flame Retardancy and Environmentally Friendly

High Voltage, EarlyView.
ABSTRACT With increasing demands for fire safety and environmental friendliness, retrofilling transformers with alternative insulating liquids has become a growing trend. However, retrofilling power transformers remains uncertain, as more residual mineral oil compromises K‐class flame retardancy, and its impact on environmental performance has yet to ...
Zhenfu Tang, Yihua Qian, Dan Zhou, Wei Hu, Feipeng Wang, Yang Xu   +5 more
wiley   +1 more source

Development of ± 550 kV DC GIS Basin Insulator

High Voltage, EarlyView.
ABSTRACT The basin insulator is a core component of the insulation system for ± 550 kV gas‐insulated switchgear (GIS). This paper, using a finite element method for multi‐physics simulations of electric–thermal coupling, determines a geometry suitable for the industrial production of ± 550 kV GIS basin insulators.
Shaohua Cao, Chengwei Jing, Siqiong Zhang, Zuodong Liang, Zehao Zhang, Fangwei Liang, Yong Yang, Geng Chen, Jinliang He, Chuanyang Li   +9 more
wiley   +1 more source

Comparison of Dielectric Recovery After Arc Burning in SF6 Gas and Its Potential Alternatives

High Voltage, EarlyView.
ABSTRACT Although sulphur hexafluoride (SF6) exhibits exceptional insulating properties, it is a potent greenhouse gas. Therefore, studying alternatives to SF6 is critical for developing environmentally friendly high‐voltage electrical equipment.
Ziqi Liu, Hao Sun, Yi Wu, Mingzhe Rong, Zeyuan Luo   +4 more
wiley   +1 more source

Impact of Electrode Distance in a Quasi-Uniform Model Electrode System on Lightning Impulse Breakdown Voltage in Various Insulating Liquids

Energies
This study presents findings on the influence of gap length distance on the lightning impulse breakdown voltage of three dielectric liquids of different chemical origins.
Wiktor Kunikowski, Pawel Rozga, Bartlomiej Pasternak, Jakub Staniewski, Filip Stuchala, Konrad Strzelecki   +5 more
doaj   +1 more source

Mechanism of Quasi‐Power‐Frequency Resonant Overvoltage Triggered by Multiple Lightning Strikes in High‐Voltage Alternating Current Systems Equipped With Shunt Reactor

High Voltage, EarlyView.
ABSTRACT This paper investigates the generation mechanism of quasi‐power‐frequency resonant overvoltage triggered by multiple lightning strikes in high‐voltage alternating current (HVAC) systems equipped with shunt reactors. Based on field measurements from a 500 kV AC system, equivalent and simplified circuit models have been established to analyse ...
Tao Liang, Tao Cui, Zhengxi Wang, Tongwei Guo, Xiaohui Wu, Hong Zeng, Jie Guo, Yanzhao Xie   +7 more
wiley   +1 more source

Study on the Coupled Effects of High‐Speed Airflow and Charged Sand on Power‐Frequency Discharge Characteristics of Conductor–Tower Gaps in Strong Wind–Sand Environments

High Voltage, EarlyView.
ABSTRACT Strong wind–sand weather in Xinjiang threatens power grid safety by increasing transmission line tripping risks. Existing studies focus on sand polarization but neglect the coupled influence of high‐speed airflow and charged sand on gap discharge characteristics.
Jianghai Geng, Yang Wang, Ping Wang, Yang Lu, Songsong Zhou, Yujian Ding, Xiaojun Zhang, Wenbing Zhuang, Yu Su   +8 more
wiley   +1 more source

Application Status and Development Trends of DC Ice‐Melting Devices in China's Power Grid

IET Smart Energy Systems, EarlyView.
This paper summarises the development history and engineering application status of DC ice‐melting devices (DCIMD) in China, analyses the principles, advantages, disadvantages and adaptability of mainstream topologies and discusses the key problems and corresponding improvement directions.
Ming Lei, Tianlong Zhang, Zhenglin Li, Jian Wang, Tao Zhang, Peng Wang, Ruiqi Zhan   +6 more
wiley   +1 more source