Monitoring and control device for electrical transmission line of the metal-clad.

摘要

The device for controlling and protecting an electric line shielded by pressurised dielectric gas, includes a number of sections, two adjacent sections being separated by a junction which permit separation of the sections. Each section includes at least one conductor maintained in position in a cylindrical sheath (1). The three phase conductors (3,4,5) are held in position by a bolted frame (20) and arms (9,10,11) within an inner aluminium sheath (2) and the outer steel sheath (1). Joints between sections of sheath are made by sliding cylinders (56,59,60) and between conductors by sliding sleeves (52). Bands of low coefficient plastic (22) maintain a space between inner and outer sheaths which allows an optical fibre (100) to run along a number of transmission line sections to a control station. In each section a microprocessor and signal convertor (102) gathers signals from thermal, partial discharge, luminous and gas flow sensors (103,104,105,106 and 107).