Cable rating for the T45 HV system

摘要

The T45 propulsion power system comprises two switchboards, linked by an interconnector. Each switchboard is fed by a WR21 GTA and a ～ 2MW DG, and supplies a transformer for ship services and a propulsion motor through a static converter. The critical requirement addressed in this paper is the installation of cables between the GTA and the switchboard, which is space limited. A minimum number of cables, with maximum flexibility is demanded. By examining the rating of the circuit, its duty cycle and the available materials for making electric cable, an argument is made for intelligent design of the cable installation. It is concluded that cabling for the T45 power system can be designed to be over-run in the full load condition without prejudicing its through-life performance, with potential savings over 30% in material and installation cost, weight, and space.