scholarly journals Flashover Characteristics of Vapor-Mist Dielectrics under Lightning Impulse and Factors to Increase the Flashover Voltage

1992 ◽  
Vol 112 (11) ◽  
pp. 905-912
Author(s):  
Masafumi Yashima ◽  
Hideo Fujinami ◽  
Tadasu Takuma
Keyword(s):  
Flashover Voltage ◽  
Lightning Impulse

Flashover characteristics of vapor-mist dielectrics under lightning impulse and means to increase the flashover voltage

1993 ◽  
Vol 113 (7) ◽  
pp. 11-22 ◽  
Author(s):  
Masafumi Yashima ◽  
Hideo Fujinami ◽  
Tadasu Takuma
Keyword(s):  
Flashover Voltage ◽  
Lightning Impulse

scholarly journals Influence of Standard Lightning Impulse Front Time Tolerances on the Flashover Voltage of Suspension Insulators

2019 ◽  
pp. 76-81
Author(s):  
J Kluss ◽  
M Chalaki-Rostaghi ◽  
K Yousefpour ◽  
Z Ahmed ◽  
F Haque
Keyword(s):  
Systematic Approach ◽  
Discharge Voltage ◽  
String Length ◽  
Time Value ◽  
Double Exponential ◽  
Flashover Voltage ◽  
Field Homogeneity ◽  
Lightning Impulse ◽  
Maximum Tolerance ◽  
Glass Insulator

For high voltage impulse testing, a standard lightning impulse is defined in IEEE Std. 4 and IEC 60060-1 as a double exponential waveform having a front time T1 = 1.2 μs ± 30% and time to half-value T2 = 50 μs ± 20%. It has been noticed that for a given specimen, it is possible to successfully pass a flashover test at one end of the T1 tolerance range while failing the same test at the opposite end of the tolerance spectrum. Consequently, a systematic approach was adopted to investigate this observation. Up-and-down tests were performed to define the disruptive discharge voltage (critical flashover voltage CFO, U50) for 1, 5, 10, and 15 unit glass insulator strings standard lightning impulses using the minimum acceptance front time value (T1 ≈ 0.84 μs). Tests were repeated using the maximum tolerance value (T1 ≈ 1.56 μs) to investigate the degree of divergence in the flashover value. Particular attention is given to the steepness (voltage-time characteristics) of the applied impulse to consider if tolerance criteria amendment is merited in a future standard revision. As the steepness impact is more renowned in non-uniform geometries, field homogeneity as a function of string length is also incorporated into the analysis.

Rigidité diélectrique d'un interface gaz–support avec contaminant métallique dans l'air sec et ses mélanges avec le SF6

2006 ◽  
Vol 84 (5) ◽  
pp. 381-398
Author(s):  
Adolphe Moukengué Imano
Keyword(s):  
Dielectric Strength ◽  
Partial Discharges ◽  
Dry Air ◽  
Voltage Stress ◽  
Flashover Voltage ◽  
Lightning Impulse ◽  
Conducting Particle ◽  
Series Of Experiments ◽  
Inception Voltage ◽  
Floating Electrode

In this paper, we conduct a series of experiments aimed at analysing the dielectric properties of compressed dry air, and some SF6–air mixtures up to 700 kPa, under application of AC 50 Hz and lightning impulse (LI) 1.2 μs/50 μs voltage. The investigations were carried out by using a cylindrical spacer model with an adhering particle on the surface under homogenous field conditions. We measure the partial discharges (PD) propagation characteristics under LI voltage stress, as well as the PD inception voltage and the flashover voltage for the contaminated particle. We also investigate the surface charge accumulation on the spacer surface under contaminated particle conditions. The results of the experiments reveal the influence a conducting particle has on the determined flashover field strength, for SF6–air mixtures compared with pure, compressed dry air. This influence is discussed for different particle lengths, but also for three different particle positions in the gap. Pure dry air achieves a higher dielectric strength when the particle gets into contact with the high voltage electrode, under negative LI voltage stress. The same result is obtained for the SF6–air mixtures, when the particle is located in the middle of the gap, as floating electrode on the spacer surface. The reported results contribute to the improvement of the models of breakdown through the interface gas–solid isolator. The application of these models should offer the possibility for considering the use of dry air, or its mixtures with SF6 which, normally have a lower relative global warming potential than pure SF6.[Traduit par la Rédaction]

Flashover voltage computation of porcelain insulators under positive polarity lightning impulse voltages

2019 ◽  
Vol 13 (5) ◽  
pp. 656-661
Author(s):  
Gowrishankar Shanmugam ◽  
Surendra Kalapati ◽  
Sunitha Karakad
Keyword(s):  
Positive Polarity ◽  
Flashover Voltage ◽  
Lightning Impulse ◽  
Porcelain Insulators

Characteristics of Negative Lightning Impulse Breakdown Voltage in Pure Water

2018 ◽  
Vol 138 (8) ◽  
pp. 441-448 ◽  
Author(s):  
Norimitsu Takamura ◽  
Nobutaka Araoka ◽  
Seiya Kamohara ◽  
Yuta Hino ◽  
Takuya Beppu ◽  
...  
Keyword(s):  
Breakdown Voltage ◽  
Pure Water ◽  
Lightning Impulse

Influence of the Test Voltage Function over Lightning Impulse Response Parameters Measured by Long Cable

2018 ◽  
Vol 138 (3) ◽  
pp. 242-248 ◽  
Author(s):  
Shuji Sato ◽  
Seisuke Nishimura ◽  
Hiroyuki Shimizu ◽  
Hisatoshi Ikeda
Keyword(s):  
Impulse Response ◽  
Lightning Impulse ◽  
Test Voltage

Ferroresonance Characteristics on Capacitive Voltage Transformer Under Lightning Impulse Voltage

2016 ◽  
Vol 9 (4) ◽  
pp. 306 ◽  
Author(s):  
I. Gusti Ngurah Satriyadi ◽  
I. Made Yulistya Negara ◽  
Daniar Fahmi ◽  
N. Wijayanto ◽  
Mochammad Wahyudi ◽  
...  
Keyword(s):  
Voltage Transformer ◽  
Capacitive Voltage ◽  
Impulse Voltage ◽  
Lightning Impulse
Sign in / Sign up

Export Citation Format

Share Document