Direct Introduction of Semicon Layers in XLPE Cable Model

Abstract

Detection and location of any partial discharge signal requires an accurate frequency dependent cable model to correctly simulate the P.D. signal attenuation during its propagation in the cable. This model should be capable of simulating the semiconducting layers which have significant effects on P.D. signal attenuation and its propagation velocity. There is a substantial need for improvements in the flexibility of transient cable model through direct introduction of the two semiconducting layers in the cable model. This can be employed, in the next step to develop a 3 phase cable model for ATP. This paper has derived an impedance formula for the semiconducting layers. The propagation characteristics of the PD signal in a cable having two semiconducting layers are evaluated by applying the derived formula, and are compared with the related characteristics in a cable with no semiconducting layer. The propagation of a PD signal applied to the sending end of the core conductor is investigated. In application of the semiconducting pick-up sensor in the cable joint, there would be a considerable high frequency voltage across each semiconducting layers which can be used for study of PD phenomenon.

Effects of Multiple Semiconducting Screens on Line Parameters and Wave Properties of Underground Cable

“…Generally, more than one semiconducting screen is present in practical cable structure. However, the detail comparative analysis of the possible effects brought by introducing multiple semiconducting screens over a single semiconducting screen in cable structure was not done in [23]- [25]. Many subsequent works considered cable with more than one semiconducting screen as a test cable, but instead of exploring the effect of multiple semiconducting screens, they confined their attention to the determination of the effect of materialistic properties of the semiconductor on different high frequency phenomenon and wave propagation characteristics in UG cable [26]- [34].…”

Effect of the Parametric Variations of Semiconductor Screen on Line Parameters and Wave Properties of Underground Cable

“…Putting (9) on (15) and performing the row operations 1 → 1 + 2 on both sides of (17) and then multiplying and decomposing the quantities on LHS of (20) gives-…”

“…Therefore the need for modification in the existing impedance and admittance model [1] of UG cable to include the effect of the semiconducting screen was arisen. After several attempts [9][10][11][12], a complete and explicit mathematical model of cable impedance considering the effect of the semiconducting layer was first derived in [13] by solving Maxwell's equations for a two-layered conductor which was later verified using circuit and numerical approach [14,15]. These works and subsequent works [10,[16][17][18][19][20] investigated the effects of the variation of semiconductor resistivity and dielectric properties on line parameters as well as wave properties of the cable considering different factors like frequency, pressure and temperatures of semiconductor sample, etc.…”

PD detection in extruded power cables: an approximate propagation model

“…A few analytical models have been developed and investigated to achieve mathematical tool suitable to characterize power cables up to hundreds of MHz and, therefore, simulate PD pulse propagation [4,[8][9][10][11][12][13][14][15]. These models can be very useful to highlight the influence on propagation constant characteristics of cable materials properties.…”

“…These models can be very useful to highlight the influence on propagation constant characteristics of cable materials properties. By the use of the analytical expressions developed in [4] and [8][9][10][11][12][13][14][15] two features have been made clear:…”