Effects of Thermal Cycles on Interfacial Pressure in MV Cable Joints.

Raffaella Di Sante,Lorenzo Peretto,Abbas Ghaderi,Alessandro Mingotti,Roberto Tinarelli

doi:10.3390/s20010169

Abstract

The use of medium voltage cable joints is mandatory when dealing with power cable faults and the installation of new lines. However, such an accessory is among the top causes of faults among the grid. To this purpose, one of the quantities monitored to understand the causes of such faults is the interfacial pressure between the insulating layers of the cable joint. In this work, the interfacial pressure between Cross-linked polyethylene (XLPE) and silicon rubber has been evaluated when the cable joint experiences thermal cycles. From the results, the pressure variation caused by the thermal cycles is demonstrated. Such a phenomenon may be connected to the generation of voids and weak spots that accelerate cable joint ageing. Therefore, proper comments and conclusions are drawn.

Highlights

Medium voltage (MV) cable joints have long been investigated due to the key role they play in underground power lines [1,2,3]
The causes of fault in MV electrical assets, and in particular in cable joints, is a current topic tackled in literature
The two cable joints under test have been subjected to thermal cycles, varying the ambient temperature

Summary

Introduction

Medium voltage (MV) cable joints have long been investigated due to the key role they play in underground power lines [1,2,3]. In order to reduce the occurrence of failures in MV cable joints, it is of major importance to understand the mechanisms leading to loss of insulation This can be obtained by specific measurement campaigns aimed at investigating the causes of fault, as is typically done for all electrical assets (e.g., instrument transformers [5,6,7,8], overhead lines [9,10], insulators [11,12,13], capacitors, [14] etc.). Different sensing systems have been proposed for continuous temperature monitoring in cable joints [18,19,20,21] and to be able to plan predictive maintenance

Results

Discussion

Conclusion