Breakdown strength measurements on cylindrical polyvinyl chloride sheaths under AC and DC voltages

Abstract

In this work, we study the effect of the applied voltage form and its rise speed on breakdown voltage of polyvinyl chloride sheaths. We first present the statistical model of Weibull used for processing the results, then we describe the experimental devices. We finally study the evolution of the nominal breakdown voltage with 8 different rise ramps up to 4.75 kV.s -1 and under different forms (AC 50 Hz, positive and negative DC voltage). A population of 50 samples has been used for calculating the mean breakdown field at each profile voltage.

Space Charge Modulated Electrical Breakdown

“…Since the application of alternating current (ac) in power transmission began in the late 19 th century, it has been realized that the dc breakdown strength is about twice or higher than the ac breakdown strength in insulating materials 1 . Throughout the 20 th century, many investigations on this phenomenon were conducted 1 2 3 4 5 6 7 8 9 10 and it was discovered that this phenomenon commonly exists in many insulating materials, from thin films to thick boards 3 . From the early 20 th century on, now-classical theories such as electrical breakdown (introduced by Hipple in 1937 11 and Fröhlich in 1939 12 ) and thermal breakdown 13 (introduced by Wagner in 1922) have been proposed.…”

“…However, it is still the lack of a widely recognized understanding, which can fully explain the origin of this phenomenon. Given overall rapid developments in electrical and electronic engineering, the incomplete understanding of the mechanism of dc and ac breakdown has restricted the development of some electrical equipment and electronic devices 4 5 6 9 .…”

Effect of different surface treatment agents on the physical chemistry and electrical properties of polyethylene nano‐alumina nanocomposites

“…DC breakdown strength was characterised by a two‐parameter cumulative Weibull distribution function, which is a widely used method to analyse the breakdown voltage data of solid insulating materials (1): where E is the experimental electric breakdown field, E 0 is the characteristic breakdown strength and represents the breakdown strength at 63.2% cumulative breakdown probability, and β is a shape parameter of Weibull distribution which describes the dispersion of the experimental results [29]. The Weibull plots of DC breakdown strength of pure PE and their composites with and without surface treatment are presented in Fig.…”

Frequency-independent breakdown strength of dielectric elastomers under AC stress

“…From high-voltage technology 3 , it is long known that the electric breakdown strength of dielectric materials can vary from AC to DC voltages and the amount of change depends on the frequency considered. For polymers, lower breakdown field strength is generally observed in AC electric stress case compared with DC 4 . This trend can have negative impact also on the DEAs since they are intended to work with dynamical electrical stresses, i.e.…”