INTRODUCTION

Extra High Voltage (EHV) power cable is a major back bone of the electric system. The reliability and safety of the electric power transmission system essentially depend upon the quality of the cable.

Traditionally Paper/ Oil Insulation systems have been used in High voltage transmission cables. However, since the advent of synthetic polymer, polyethylene (PE) and cross-linked polyethylene (XLPE) have been used as an insulation material. In most countries the use of polyethylene have been limited to the cross-linked version (XLPE) due to major advantage XLPE has over PE in that it enables the cables to be operated at a higher temperature and results in higher current carrying capacity.

Cross-linked polyethylene is also considered to be the material of choice due to its ease of processing and handling as compared to paper/oil. In addition, the low dielectric losses of cross-linked polyethylene which become increasingly important with increase in voltage as well as high intrinsic electrical strength makes it the favored material for the range of extra-high-voltage applications.

These cables can be designed to meet requirements of international standards such as IEC, ICEA, UL, DIN, VDE, AS/NZS, TIS, IS as well as other standards specified by customers.