High Performance Thermoplastic Cable Insulation Systems

Crosslinked polyethylene (XLPE) has been widely used as power cable electrical insulation for many years. However, with a maximum continuous operating temperature of similar to 90 degrees C, this impacts both continuous and emergency cable ratings and, consequently, has implications for power network operational flexibility. In this paper, we describe the principles underpinning new and patented thermoplastic insulation systems that haw been actively designed to exhibit Unproved properties. Polyethylene and polypropylene blends are described that show significant improvements relative to the performance of XLPE in terms of enhancements to breakdown strength, with tests being unable to breakdown mini-cable specimens. Mechanically, the resultant materials exhibit an appropriate degree of flexibility. The results obtained suggest that thermoplastic blend materials can exhibit significantly enhanced thermal and electrical performance with respect to XLPE These improvements translate to a wry favorable position for enhanced cable performance, including maximum operating temperature. Consequently, MV and HV power cables with significantly enhanced flexible operation can be produced, with the potential to offer system operators the increased emergency ratings necessary to ease system constraints.