Results 131 to 140 of about 370 (172)

Study on the transient characteristics of 1100kV VFTO

2017 4th International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST), 2017
The very fast transient overvoltage (VFTO) generated by switching disconnector (DS) in gas insulated substation (GIS) with the features of high amplitude, short rise-time and complex frequency components, may cause damage to the insulation of electrical equipment.
Wu Xixiu, Zhou Fan, Wu Shipu, Cheng Shimin, Reem A. Almenweer   +4 more
openaire   +1 more source

Analysis of VFTO in 1000kV GIS

2020 6th Global Electromagnetic Compatibility Conference (GEMCCON), 2020
With the development of UHV (Ultra High Voltage) transmission technology, GIS(Gas Insulated Substation) is usually used at all levels of substations, but it will produce VFTO (Very Fast Transient Overvoltage)when operating its isolating switch. It has the characteristics of large amplitude, high frequency and fast fluctuation.
openaire   +1 more source

Research of VFTO in 110kV minimized GIS

2015 5th International Conference on Electric Utility Deregulation and Restructuring and Power Technologies (DRPT), 2015
110kV minimized gas insulated substation (GIS) has been widely used in China, due to its great electrical properties. The closing or opening operation of disconnector switches (DS) and circuit breaker (CB), and single-phase ground fault are all probable to cause the very fast transient overvoltage (VFTO), which is a threat to the power system. Compared
He Qifei, Hao Zhiguo, Guo Jie
openaire   +1 more source

The influence of the distributed trapped charge on VFTO

2010 5th International Conference on Critical Infrastructure (CRIS), 2010
In this paper, the nodal admittance equation is derived for analyzing the response of the transmission line under the residual voltage due to uniformly distributed charge along the line in Laplace domain. We equivalent the trapped charge to the current sources which are located at near-end and far-end when the disconnector switching is operated.
Hongyang Yu, Binxian Lu
openaire   +1 more source

Characteristic Analysis on Suppressing VFTO in GIS by Ferrite

Advanced Materials Research, 2013
When disconnecting switches were operated,Very Fast Transient Overvoltage (VFTO) did great harm to power systems and their equipments in Gas Insulated Substations (GIS). Although VFTO can be suppressed by a few of known methods, there were some problems.
Xiang Gen Gan, Shui Ping Zhong, Sheng Wei, Dong Bao Yang   +3 more
openaire   +1 more source

Design of Triggering Device for VFTO Measurement System

Advanced Materials Research, 2012
Very fast transient overvoltage (VFTO) can be generated during the operation of disconnect switch (DS). Especially in ultra high voltage (UHV) gas insulated substation (GIS), VFTO is a threat to the safety of the power system equipment. It is very important to measure VFTO waveforms accurately.
Gong Chang Yue, Yu Rong Jia, Jia Xi He, Wei Dong Liu   +3 more
openaire   +1 more source

Design of a New Busbar for VFTO Suppression and Analysis of the Suppression Effect

Electronics
Very fast transient overvoltage (VFTO) is characterized by short wavefront time, high amplitude and wide frequency. VFTO poses a threat to the safe operation of power equipment.
Xixiu Wu, Xiwen Chen, Bolun Du, Yinglong Diao, Huan Wang   +4 more
exaly   +2 more sources

Damping of VFTO by RF resonator and nanocrystalline materials

2013 IEEE Electrical Insulation Conference (EIC), 2013
Very fast transient overvoltages (VFTO) are a well known phenomena in gas insulated switchgears (GIS). The main reasons for VFTO are switching operations of disconnectors. Thereby, several pre- or restrikes between the switching contacts occur and initiate steep voltage rises propagating inside the GIS.
S. Burow, W. Kohler, S. Tenbohlen, U. Straumann   +3 more
openaire   +1 more source

Measurement of VFTO Based on the Transformer Bushing Sensor

IEEE Transactions on Power Delivery, 2011
Disconnector switching operations in large gas-insulated switchgear (GIS) systems may produce very fast transient overvoltages (VFTOs), causing high electric stress to other apparatuses in the substation, such as power transformers. This paper presents a VFTO measuring technique based on a transformer bushing sensor, which consists of the transformer ...
Guo-Ming Ma, Cheng-Rong Li, Jiang-Tao Quan, Jian Jiang   +3 more
openaire   +1 more source

Lumped parameter modeling of transformer windings under VFTO

2011 4th IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, 2011
Very fast transient overvoltage (VFTO) is very dangerous for the transformer which is directly connected to gas insulated substations (GIS). In order to study the voltage distribution in transformer windings under VFTO, a new model named the Piecewise Lumped Parameter (PLP) model is proposed.
Juan Du, Guishu Liang, Haifeng Sun, Xin Liu, Xixiao Liu   +4 more
openaire   +1 more source